AeroElectric-Archive.digest.vol-ev
September 20, 2005 - October 03, 2005
> contacted me off list) false tripping by the OVP and resulting
> alternator
> failure where the alternator was internally regulated and the "B" lead
> contactor was the common type that not only bounced on opening (due
> largely
> to the recommended diode) and also to the resulting load dump peak
> voltage
> that greatly exceeded the contactor maximum contact voltage rating.
> Heavy
> contact arcing was documented. This resulted in the recommended
> Kilovac
> contactor as its the only reasonable cost contactor with the proper
> ratings
> and there is no coil diode to cause problems on contact opening.
>
> 5. We then had a system design solution with a no false tripping
> OVP and a
> "B" lead contactor that did not damage the alternator. Eric is now
> selling
> the OVP design and has on occasion the Kilovac contactors that
> allow safe
> "B" lead opening.
>
> 6. I further investigated "rebuilt alternators" and found the term
> misleading. Only parts that were failed were replaced. The term
> should be
> repaired not rebuilt. The popular ND 55 amp alternator has been
> around for
> more than 20 years and many have been rebuilt several times. Who
> knows the
> quality of the current regulator? Thus only brand NEW alternators
> should be
> used.
>
> 7. Replacing the fast trip and occasional false tripping OVP with a
> modern
> design eliminates false trips. Eliminating the Crow bar eliminated
> the hi
> current and its side affects (see below). If used, the proper "B" lead
> contactor will prevent alternator damage often caused by the
> improperly used
> common contactor that is not designed or specified for this specific
> application and further hindered with the incorrect application of
> a diode
> across the coil against major manufacturers worked wide. In fact
> the common
> diode across the coil is not recommended anywhere any time by relay
> manufacturers. That its very common in use does not mean its a good
> approach, It simply means that most engineers are lazy and copy
> what has
> been done in the past rather that research what is recommended so
> the diode
> persists even with its being the last and worst choice in a list of
> options.
>
> IN conclusion the test results showed that much of the alternator
> failures
> were the direct result of the OVP design and associated contactor.
> Its not
> known if poor alternator regulators were a factor but even good
> ones are
> very likely to be damaged by the current design contactor used. Its
> clear
> that the contactor used has a very high potential of regulator
> damage and
> when coupled with a false trip prone (in some as yet defined
> aircraft wiring
> or operations) is the root cause.
>
> Use a modern non-crowbar OVP design and a contactor designed for the
> application resolved most of the problem. Its not possible to
> ignore the
> likely hood of lesser quality regulators in rebuilt alternators so
> only new
> alternators should be used.
>
> With the demonstrated extremely high reliability of the ND brand of
> internally regulated alternators is very questionable that there is
> a need
> for more that having the OVP simply remove the voltage to "I" lead
> (the
> field control lead) that shuts down the alternator. I have been
> unable to
> find any repair shop that has ever heard of an ND alternator having
> uncontrolled runaway failure. No output or hi output that is still
> controllable with the "I" lead. Prop bolts or crank shafts are more
> likely
> to fail and yes I have a report of a light twin having both engines
> prop
> bolts failing.
>
> Now for the hi current related problems.
>
> In an steel tube reinforced cockpit like the Glastar (or other
> production
> aircraft) its been proven that even the normal bus loads can
> magnetize the
> tube structure and cause compass errors of as high as 30 degrees. I
> previously referenced a manufacturers mandatory service bulletin that
> addressed this issue and also discussed with a owner of that type
> aircraft
> that had it happen to him. He is highly educated and a long time
> IA. The
> compass in question was a suspended well above the affected tubes
>
> This tells me that even 50 amp buss circuits need special wire
> routing and
> forget the 100+++ current transients from a crow bar.
>
> This alone says if you have a steel tubular cabin be careful and
> forget a
> crow bar approach.
>
> In any event this is my last word on either subject even if the
> misquoting
> etc continues.
>
> Paul
>
>
> ----- Original Message -----
> From: "Robert L. Nuckolls, III" <nuckollsr(at)cox.net>
> To:
> Subject: Re: AeroElectric-List: RE: Breaker Interrupt Rating
>
>
>>
>>
>>
>>
>>>
>>>
>>> Bob;
>>>
>>> I DID post (to this list) the exact specific technical parts etc.
>>> details
>>> of
>>> my test and you seemed never recognize that fact.
>>>
>>
>> Forgive me. I WAS watching for such information since I was the
>> one who requested it. Can you give me an approximate date or repeat
>> your post. I'll so search the archives if necessary. Give me one
>> part number you cited. It will make the search so much faster.
>>
>>
>>> That I used words and not
>>> a schematic is not important in this case as a schematic is not
>>> needed
>>> with
>>> such a simple circuit. I did use a different wiring diagram (of your
>>> schematic) to duplicate what is in my aircraft however.
>>>
>>
>> Then is it a fair presumption that as an skilled and articulate
>> engineer that you've documented that portion of your system's
>> wiring in a manner that can be scanned and shared?
>>
>>
>>
>>> But you cannot duplicate my results (as I under stand what you
>>> mean by
>>> duplicate) unless you use the exact same parts I used. The same
>>> identical
>>> part, not a part of the same brand and part number is required in
>>> this
>>> case
>>> because of the very wide variation in the parts tolerances.
>>>
>>
>> Absolutely! I've never done a test report without identifying
>> or at least making full disclosure of parts used, techniques,
>> measurements, etc. I'd be pleased for you to take the parts I
>> used in
>>
>> http://www.aeroelectric.com/articles/Crowbar_OV_Protection/
>> DC_Power_System_Dynamics_C.pdf
>>
>> and show me how I mis-read or mis-interpreted data at the risk
>> of making a bad deduction. You seem to accept the test results
>> I posted but counter with "that's not what I got with MY test."
>> Fine . . . tell us how you did it.
>>
>>
>>
>>> Only if a worst case analysis is properly done and the range of test
>>> results
>>> is determined can any test be duplicated by another using different
>>> physical
>>> parts of the same part number. The part to part variation in most
>>> cases
>>> and
>>> clearly in this case is simply too large.
>>>
>>
>> I'm mystified as to this part-to-part variation you cite.
>>
>>
>>> Crow bar short circuit currents can vary from well under 100 amps
>>> to over
>>> 400 amps depending on the parts used and the wiring diagram used to
>>> implement the same schematic.
>>>
>>
>> I don't doubt it . . . but I'm still trying to visualize the
>> 400A case.
>>
>>
>>> Thus any test that results in a current from around 100 amps to
>>> around 400
>>> amps is in fact a duplication of another's test results in this
>>> case.
>>>
>>> Where there are small parts variations the duplicated test
>>> results will be
>>> much closer but NEVER identical.
>>>
>>
>> You don't have to sell me on stacked up variability and test
>> tolerances . . . I've been doing this since high school
>> physics.
>>
>>
>>
>>> For example the following is true:
>>>
>>> #1 CB ratings vary widely in resistance and trip time, in fact,
>>> close to
>>> a
>>> 10 -1 variation. between parts of the same brand and parts from
>>> other
>>> brands. Nothing strange about My CB having an internal resistance
>>> 1/10 of
>>> the one you used. CB internal resistance can and does vary from
>>> approx
>>> 0.003
>>> to over 0.030 ohms; a 10-1 variation
>>>
>>
>> This I really need to see. What brand and part number exhibits
>> such variability? The problem I'm having is that trip
>> characteristics
>> are an I(squared)*T event that depends on heat generated within
>> the current sensing part of the breaker. ANY breaker that shows
>> a 10:1 variability in resistance should be expected to show
>> a similar variability in trip characteristics. There are no
>> manufacturers I work with that would offer me such a product.
>>
>> Gee, a 5A breaker that can open anywhere between 2.5 and 25 amps!
>>
>>
>>
>>> #2 Battery internal resistance also varies again as much as 10-1
>>> depending
>>> on the battery brand and ratings. My batteries have 1/5 to 1/10 the
>>> internal
>>> resistance of your battery. But then I do not use the Panasonic
>>> brand or
>>> similar types.I do use a very popular PS625 (dual at that)
>>> battery with
>>> much
>>> higher specifications in most important parameters. Not that the
>>> Panasonic
>>> is bad but its not nearly the same in several (important to me)
>>> electrical
>>> specifications.
>>>
>>
>> As I've repeated many times, I don't care if your battery
>> is ZERO ohms. There's a rational, recommended installation
>> technique for using my products where the MAJOR contributor
>> of loop resistance is wiring, a minor contributor is circuit
>> breaker heater resistance with so small an amount coming from
>> the battery and fatwires that they can be ignored. Nonetheless,
>> I'm intently interested in your .0035 to .0017 ohm battery.
>> Do I recall that you're building a Subaru powered two-place?
>> Batteries I can find with this level of performance start out
>> at 60 pounds and go up from there. I presume you ARE planning
>> on carrying passengers in this airplane . . .
>>
>>
>>
>>> #3 My wiring was an exact duplicate of what I have in my aircraft
>>> and is a
>>> fraction of what you had in your test. My wiring is less that 1/2
>>> the
>>> internal resistance of your test wiring.
>>>
>>
>> Very good. The systems I recommend and illustrate in the Z-figures
>> are rooted in practices found in the vast majority of Certified
>> and OBAM iron. Of course one should not toss away lots of
>> performance in wire drops and soggy batteries . . . but then,
>> wiring everything with 00 gage and installing batteries that
>> would crank a Detroit Diesel in a N. Dakota winter has some
>> seriously diminished returns on overall system design. If you
>> have 1/2 the loop resistance illustrated in my experiments, you
>> must have a rational for increased battery and wire sizes at the
>> sacrifice of useful load. We'd be interested in understanding
>> the design goals by which you arrived at this exceedingly low
>> loss system.
>>
>>
>>> I measures the battery internal resistance as well as the CB and
>>> wiring
>>> resistances before and after the testing series.
>>>
>>> The same CB was used in the simulated worst case test where the
>>> current
>>> was
>>> 700 amps and there were at least 50 tests of the real circuit
>>> where the
>>> current was 400 amps. No degrading of any part including the SCR
>>> in your
>>> crow bar circuit which was over stressed several times its max
>>> rating.
>>>
>>
>> Then no doubt you can tell me what the battery part number was,
>> what
>> circuit
>> breaker was used, what SCR was used, what diameters and lengths of
>> wires were used . . . I'll pay you my consulting fee for the time
>> it takes you to type that data into a posting here on the list.
>>
>>
>>
>>> This overstressing and lack of damage does not mean its a good
>>> design idea
>>> and more importantly does not mean that all CB's will survive
>>> with no
>>> damage.
>>>
>>> In this case the main short current drivers are the Battery, CB
>>> and wiring
>>> resistances.
>>>
>>> That alone suggests that 400 amps is easy to achieve as the circuit
>>> resistance to get 400 amp vs. 130 amps only needs to decrease to
>>> 1/3 or
>>> so.
>>>
>>> Bottom line: I had 6 EXPERT, experienced, real electrical engineers
>>> review
>>> what I have done and ALL agreed with my test setup and suggested
>>> 400 amps
>>> was not the max current possible as I had not used the worst case
>>> analysis
>>> parts.
>>>
>>
>> Then may we expect to see their names on the byline for a
>> detailed report? As long you've opened the door to name dropping,
>> I'll claim real signatures of dozens of folks representing systems
>> designers, DERs, program managers, test pilots and test
>> technicians who executed paperwork certifying this system on
>> Mooney, Piper, Beech, Cessna and Cirrus aircraft. This is over
>> and above thousands of OBAM aircraft customers who seem to be
>> getting
>> satisfactory performance from their purchases.
>>
>> For the moment, I have no greater assurances of the existence
>> of your six "experts" than I do of the half dozen or so of
>> my customers you claim were ALL having nuisance trip problems
>> NONE of whom would call me for assistance and ALL of which
>> declined
>> an opportunity to exercise my well published 100% satisfaction
>> or money back guarantee.
>>
>>
>>> I had hoped this issue had gone away months ago as we will never
>>> agree. I
>>> only post here when I feel my comments are being misquoted to the
>>> extreme.
>>> Seems that will never end and frankly I am saddened that it seems to
>>> continue.
>>>
>>
>> The List is a classroom. Folks will always be asking about these
>> issues and as one of several teachers on the list, I have a duty
>> to sort myth, old mechanic's tales, and bad science from
>> fact as I understand it. If you want this discussion to end, then
>> carry out your past threats never to post again. If you have
>> facts to dispute, then be a teacher and publish counter balancing
>> facts. Either is fine with me . . . but don't expect me not
>> to continue to counter rumors, yours or anyone else's. I'm sure
>> Greg Richter is fond of telling tales over a beer about how
>> he crossed swords with that wild-eyed guy in Wichita and the
>> telling probably gets better with each pitcher full. He too
>> was amazingly reluctant to answering a single direct question.
>> If you're ready to mark me off as hopeless, you're welcome to
>> bow out . . .
>>
>> I've even offered $cash$ rewards for simple answers to
>> specific questions. It would be worth it to me. My exorbitant
>> consulting rate at the moment is $75/hour. If you could save
>> me a hour of time digging around trying to figure out exactly
>> how you arrive at some of your mystifying numbers, then
>> I'd be money ahead to pay you cash for the data. I'd rather
>> use the hour to add value to someone's airplane as opposed to
>> sorting your jigsaw puzzle with many missing pieces. How about
>> filling in your version of the pieces in the first figure on
>> page 2 of the paper cited above and show us all how you
>> generated a 400A crowbar event?
>>
>>
>>
>>> The basic issue of OVP crow bar short to open a CB is the real
>>> discussion
>>> where you believe its a good approach and I disagree is the
>>> fundamental
>>> issue and the short current is a distraction.
>>>
>>
>> Hmmm . . . at least it's devolved to a 'distraction' . . .
>> there have
>> been times past when the crowbar event could be expected to cause
>> all manner of bad day including in-flight reset of EFIS systems
>> and engine stoppage. If you have a better approach, you're
>> most welcome to join the rest of us in the free marketplace.
>>
>>
>>> Please do not snip this email as it tends to put my comments out of
>>> context
>>> and change the meaning/intent of my comment.
>>>
>>> Better yet simply do not reply and we can both put this stupid
>>> debate to
>>> rest and get on with productive discussions.
>>>
>>
>> If it's stupid, it's only because you're not debating. Any high
>> school
>> debate teacher would have tossed you out of this classroom
>> years ago.
>> My physics teacher would have tossed you out of his class too.
>> I saw
>> him do it to a kid that "dry labbed" an important assignment.
>> This is
>> not a classroom on debate, it's a classroom of simple ideas and
>> physics
>> as they relate to building the best airplanes to have ever flown.
>> Show us your setup, show us your work and show us your data.
>>
>> Okay, how's this for a productive topic:
>>
>> How do you propose we offer a means by which an OBAM aircraft
>> community a means for installing an internally regulated
>> alternator
>> such that its operation transparent to the paradigm under which
>> generators and alternators have been operated on aircraft since
>> day-one to wit:
>>
>> (1) Absolute pilot control over engine drive power source.
>>
>> (2) Failure and hazard free switching of the engine driven power
>> source at any time and under any conditions.
>>
>> . . . of course, answers to the above will offer the OBAM
>> aircraft
>> builder a means by which any attractive OV protection philosophy
>> can be added assuming he/she so desires. These are the questions I
>> thought
>> you were going to answer when you went off to do the tests over a
>> year ago. Presumably you have the data necessary to make
>> considered
>> recommendations. We're all ears.
>>
>> Bob . . .
>>
>>
>>
>>
>
>
________________________________________________________________________________
From: | Ken <klehman(at)albedo.net> |
Subject: | Re: Wire selection |
I don't think you want to run multiple wires to feed a single device.
What protects you from fire if one of the wires shorts?
This technique would be acceptable to lower the voltage drop in the
wiring as long as the fuse was no larger than one of the wires can
handle. It would not be acceptable to use a larger fuse and multiple
wires to increase the current available to a device as then you don't
have appropriate wire protection.
That said - I mostly used awg 18 fused at 10 amps. I also used a good
deal of awg 22 for signal wires and such as it is much easier to
fabricate assemblies that use small connectors and much more flexible in
bundles. But it is almost inescapable that you will need some larger
wire for the alternator, batteries, and perhaps other things. I think
you will find that the total cost of the wire is less than you may be
imagining.
Ken
Ernest Christley wrote:
>
>I'd like to keep my wire rack nice and simple. Instead of having
>multiple spools of various wire sizes, I think it would be beneficial to
>have just one spool of a multistranded cable. I don't see it weighing
>significantly more. There's just not enough wire in the plane to make a
>difference. The cable is more expensive, but the installation would be
>simpler and safer. Simpler since, for instance, there would only be one
>run of wire out to the wingtip lights. Safer since the wire by default
>would have an extra jacket. Before anyone gets a chance to say it, I am
>indeed accepting a less than optimum design in exchange for a lack of
>the need to plan carefully. My response is that the offset from optimum
>will not have measurable results in the final product, and the best laid
>plans of mice and men... (so, it's 4:00 on Saturday. You've got a roll
>of 22AWG left, but what you really need is 2ft of 20AWG. Aaargh!)
>
>So, with this goal in mind, what would be a good wire size that would
>basically cover all the wiring needs, with the obvious exception of the
>starter? 18AWG? 20AWG? Certain high current devices, like pitot heat,
>could use multiple strands in a cable, or lower current technologies,
>like Eric's thermal switch design. Stenair has 3 and 4 strand cables of
>22AWG, which I think is a little small. Is there a good source for
>larger aviation grade cables?
>
>
>
________________________________________________________________________________
From: | "John Erickson" <Droopy(at)ericksonjc.com> |
I've searched the archives and can't seem to find the answer anywhere. I
need to replace the connector on the back of the rack for my KT-76
transponder. Anyone know what part number and manufacturer I could get
one from to build a new harness?
Thanks,
John
RV-10 #40208 Wings
________________________________________________________________________________
From: | Jim Oke <wjoke(at)shaw.ca> |
Subject: | Re: Wire selection |
Actually this wiring technique is used on some large aircraft such as
the DHC-8-102 that I fly for work.
Multiple runs are used in some of the main bus feeds possibly for
redundancy and possibly to reduce weight. Theory is that for equal
weight of wire, a number of small conductors will have more surface area
and carry more current than than a single large conductor. Perhaps a
design consideration in transport aircraft but hardly likely to be
worthwhile in a light aircraft.
Circuit protection is via a circuit breaker at each end of each wire in
the group. The idea is that if a short occurs in the middle of a wire,
the CB at one end will open normally but current will be fed into the
other end of the wire via the others in the run and then open the CB at
the other end isolating the wire. The remaining conductors will still be
available to power the device or buss but at a reduced capacity.
So more breakers are needed = higher parts count + more installation
time & effort + ongoing maintenance. Perhaps worthwhile if you need 200
amps at a bus but not for a 5-10 amp landing light.
Jim Oke
Wpg., MB
RV-6A
Ken wrote:
>
>I don't think you want to run multiple wires to feed a single device.
>What protects you from fire if one of the wires shorts?
>
>This technique would be acceptable to lower the voltage drop in the
>wiring as long as the fuse was no larger than one of the wires can
>handle. It would not be acceptable to use a larger fuse and multiple
>wires to increase the current available to a device as then you don't
>have appropriate wire protection.
>
>That said - I mostly used awg 18 fused at 10 amps. I also used a good
>deal of awg 22 for signal wires and such as it is much easier to
>fabricate assemblies that use small connectors and much more flexible in
>bundles. But it is almost inescapable that you will need some larger
>wire for the alternator, batteries, and perhaps other things. I think
>you will find that the total cost of the wire is less than you may be
>imagining.
>
>Ken
>
>Ernest Christley wrote:
>
>
>
>>
>>I'd like to keep my wire rack nice and simple. Instead of having
>>multiple spools of various wire sizes, I think it would be beneficial to
>>have just one spool of a multistranded cable. I don't see it weighing
>>significantly more. There's just not enough wire in the plane to make a
>>difference. The cable is more expensive, but the installation would be
>>simpler and safer. Simpler since, for instance, there would only be one
>>run of wire out to the wingtip lights. Safer since the wire by default
>>would have an extra jacket. Before anyone gets a chance to say it, I am
>>indeed accepting a less than optimum design in exchange for a lack of
>>the need to plan carefully. My response is that the offset from optimum
>>will not have measurable results in the final product, and the best laid
>>plans of mice and men... (so, it's 4:00 on Saturday. You've got a roll
>>of 22AWG left, but what you really need is 2ft of 20AWG. Aaargh!)
>>
>>So, with this goal in mind, what would be a good wire size that would
>>basically cover all the wiring needs, with the obvious exception of the
>>starter? 18AWG? 20AWG? Certain high current devices, like pitot heat,
>>could use multiple strands in a cable, or lower current technologies,
>>like Eric's thermal switch design. Stenair has 3 and 4 strand cables of
>>22AWG, which I think is a little small. Is there a good source for
>>larger aviation grade cables?
>>
>>
>>
>>
>>
>
>
>
>
________________________________________________________________________________
From: | "Dave Morris \"BigD\"" <BigD(at)DaveMorris.com> |
Subject: | Re: Wire selection |
I think I detect at least three problems with this logic.
At 10:48 PM 9/20/2005, you wrote:
>Theory is that for equal
>weight of wire, a number of small conductors will have more surface area
>and carry more current than than a single large conductor.
At DC, surface area isn't as important as cross section area.
>The idea is that if a short occurs in the middle of a wire,
>the CB at one end will open normally but current will be fed into the
>other end of the wire via the others in the run and then open the CB at
>the other end isolating the wire. The remaining conductors will still be
>available to power the device or buss but at a reduced capacity.
Once the breaker opens on one end, nothing will flow into the other
end. And what will reduce the capacity?
>So more breakers are needed = higher parts count + more installation
>time & effort + ongoing maintenance. Perhaps worthwhile if you need 200
>amps at a bus but not for a 5-10 amp landing light.
I agree. I think it's way overkill for OBAM. It's the kind of thing you
do in a spacecraft or an aircraft that is going to be shot at and has to
survive no matter the cost.
Dave Morris
________________________________________________________________________________
Subject: | Re: Wire selection |
From: | "Matt Prather" <mprather(at)spro.net> |
Hi Dave,
Comments below.
>
>
snip
>>The idea is that if a short occurs in the middle of a wire,
>>the CB at one end will open normally but current will be fed into the
>> other end of the wire via the others in the run and then open the CB at
>> the other end isolating the wire. The remaining conductors will still
>> be available to power the device or buss but at a reduced capacity.
>
> Once the breaker opens on one end, nothing will flow into the other
> end. And what will reduce the capacity?
>
snip
I think the idea is that there's a breaker on each end of each conductor.
The idea is that if a fault develops on only one of the wires in a bundle,
it will be powered from both ends of the bundle... The remaining
conductors aren't faulted. Thus, there will voltage on both ends. That
means that in order for the remaining wires in the bundle to stay hot, the
breaker on each end of the faulted wire will have to open. Does that
clear it up? I agree that this is ridiculous increase in parts count...
>
> Dave Morris
>
Regards,
Matt-
________________________________________________________________________________
From: | <jlundberg(at)cox.net> |
Does anyone know where to buy a 80amp/50mv shunt for an Electronics International
volt/amp meter. I bought a used digital meter at Oshkosh and it did not have
the shunt. I have found 50 and 75 amp from a marine supply but not the 80
amp version.
Thanks.
John Lundberg
Los Angeles, cA
________________________________________________________________________________
From: | <jlundberg(at)cox.net> |
The connector for the KT-76 is available from Mouser Electronics. It is the same
connector used on the Narco MK12D, and the PS Engineering audio panels as well
as others.
Best to check before ordering as the Narco AT50/50A/155/165 transponders use different
pins. Compare the diagram to your connector.
Connector is 538-09-50-6125 $0.79
Terminal pins 538-08-05-0302 $0.28
John Lundberg
Los Angeles, CA
________________________________________________________________________________
From: | <gmcjetpilot(at)yahoo.com> |
Subject: | Re: 80 Amp Shunt |
shunts of all amp ratings http://www.deltecco.com/indexpage.html
OR http://www.cshunt.com/pdf/la.pdf
From:
Subject: AeroElectric-List: 80 Amp Shunt
Does anyone know where to buy a 80amp/50mv shunt for an Electronics International
volt/amp meter. I bought a used digital meter at Oshkosh and it did not have
the shunt. I have found 50 and 75 amp from a marine supply but not the 80
amp version.
Thanks.
John Lundberg
Los Angeles, cA
---------------------------------
Click here to donate to the Hurricane Katrina relief effort.
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: 80 Amp Shunt |
>
>shunts of all amp ratings http://www.deltecco.com/indexpage.html
>
>OR http://www.cshunt.com/pdf/la.pdf
>
>
>From:
>Subject: AeroElectric-List: 80 Amp Shunt
>
>
>Does anyone know where to buy a 80amp/50mv shunt for an Electronics
>International
>volt/amp meter. I bought a used digital meter at Oshkosh and it did not have
>the shunt. I have found 50 and 75 amp from a marine supply but not the 80
>amp version.
Do I presume correctly that the instrument is intended to
read 0-100% as a loadmeter? I.e., 50mv = 100 on instrument?
If so, then sizing the shunt to the alternator is the
appropriate thing to do. 80A is a bit of an odd size
but shunt fab shops can built to suit. If you can find
a shunt just over 80A, like 100A, it's easy to re-calibrate
it by cutting down the shunt element with a file. I can
do it for you if you can't find an exact 80. Also, you could
consider using the 75A shunt . . . it would simply "derate"
your alternator by 5A. It's doubtful that you'll ever need
to know what the loads are up so close to the top end of
the alternator's capability.
Bob . . .
________________________________________________________________________________
From: | Christopher Stone <rv8iator(at)earthlink.net> |
Subject: | Re: 80 Amp Shunt |
Shunts...
B&C has them.
http://www.bandcspecialty.com/parts.html
cs
-----Original Message-----
From: jlundberg(at)cox.net
Subject: AeroElectric-List: 80 Amp Shunt
Does anyone know where to buy a 80amp/50mv shunt for an Electronics International
volt/amp meter. I bought a used digital meter at Oshkosh and it did not have
the shunt. I have found 50 and 75 amp from a marine supply but not the 80
amp version.
Thanks.
John Lundberg
Los Angeles, cA
________________________________________________________________________________
From: | Ernest Christley <echristley(at)nc.rr.com> |
Subject: | Re: Wire selection |
Ok, multiple strands to increase capacity is not applicable to light
aircraft. I can easily see the safety issues.
I also agree that 18AWG for the "bird's nest behind the panel" would
make for a difficult work environment. I'll need to drop down to 22AWG
for most of that.
Furthermore, I agree that using a multistranded cable will increase
weight somewhat. I believe the weight is offset by the safety of an
additional jacket for the wire, the clean look of the installation, and
the simplicity of running the wire. It is just easier to make a cable
go where you want it to, vs several individual wires that you just spent
hours tying together.
Someone mentioned cost. The cable I'd like to have would be more
expensive, but not significantly so. If you count the time tying
together individual wires, the cable could be considered cheaper. But,
all told, I don't see enough of a difference to really make an argument
either way.
So, Stenair has a fine selection of aircraft wire and cable in all sorts
of multi-colored goodness. But their cable is only available in 22AWG.
Does anyone have a source of aircraft wire with a greater selection?
--
,|"|"|, |
----===<{{(oQo)}}>===---- Dyke Delta |
o| d |o www.ernest.isa-geek.org |
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: Wire selection |
>
>
>Ok, multiple strands to increase capacity is not applicable to light
>aircraft. I can easily see the safety issues.
>
>I also agree that 18AWG for the "bird's nest behind the panel" would
>make for a difficult work environment. I'll need to drop down to 22AWG
>for most of that.
>
>Furthermore, I agree that using a multistranded cable will increase
>weight somewhat. I believe the weight is offset by the safety of an
>additional jacket for the wire, the clean look of the installation, and
>the simplicity of running the wire. It is just easier to make a cable
>go where you want it to, vs several individual wires that you just spent
>hours tying together.
>
>Someone mentioned cost. The cable I'd like to have would be more
>expensive, but not significantly so. If you count the time tying
>together individual wires, the cable could be considered cheaper. But,
>all told, I don't see enough of a difference to really make an argument
>either way.
>
>So, Stenair has a fine selection of aircraft wire and cable in all sorts
>of multi-colored goodness. But their cable is only available in 22AWG.
>Does anyone have a source of aircraft wire with a greater selection?
I've been following this thread and the majority of the
simple-ideas and deductions made therefrom have been
sound and correct.
I'll offer the following enlargements to the discussion.
While arrays of smaller wires might seem to reject heat
better than a single large wire of the same cross-section,
there are bundling effects that tend to wash away all the
advantages with respect to heat rejection.
Some of you may recall an experiment I illustrated some months
ago wherein the question was, "How much current does it take
to chase the smoke out of a 22AWG wire?"
In the photo at
http://www.aeroelectric.com/Pictures/20A_22AWG.jpg
There's a 22AWG Tefzel wire with tiny thermocouple attached
and strung out in free air. At the time I took the picture,
the wire had been loaded to 20A for several minutes. No smoke.
In fact, I don't think the wire had reached operating limits
for Tefzel even yet. I tried to go higher in current but the
120 line to my shop was inadequate to the task of supporting
my largest bench supply . . . I need to run in a 240 line
to finish the experiment.
Given what I've demonstrated above, it seems really strange
that in some cases, 22AWG wire is de-rated to 3A max continuous
in bundles where the majority of wires are also loaded to
the hi side of their max rating. Just keep in mind that wires
are rated based on temperature limits of the insulation and
the ability of the wire, as installed, to reject heat. You're
almost never in danger of burning a wire due to low duty cycle
overloads several times the wire chart rating for any given
application. The breaker opens long before the wire is really
at-risk for damage. Fuses open even faster.
In the aircraft business, pre-bundled wires are used only
where essential. Twisted pairs, trios, and/or to add shielding,
etc. The economics of using pre-bundled wires has been
researched dozens of times over the years and found to be
very limited in applicability and never cost effective
over the building of specific bundles of single strands
of wire when twisting or shielding was not necessary.
If one is desirous of improving the looks of an installation
by the use of pre-bundled wires, just keep in mind that the
$time$ you spend achieving this appearance is $time$ that's
no longer available to push other details of your project
forward. I've had people write and tell me they were dropping
of the List because if they'd spend the same $time$ working on
sheet metal and rivets as they have expended on sifting
all that interesting "sand" on the List, they'd be much
further along.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | HHK MAX fuse holder and 6AWG wire splicing |
A few days ago I promised a comic book on wire splicing
in general and specifically, using the HHK in-line fuse
holder for the MAX series fuses.
http://www.aeroelectric.com/Mfgr_Data/Fuses_and_Current_Limiters/Bussman/MAX_InLine.pdf
http://www.aeroelectric.com/Mfgr_Data/Fuses_and_Current_Limiters/Bussman/maxifuse.pdf
I used to get these holders for about $10 at the local
parts stores. I visited 5 stores and nobody has them
any more. They're a low volume item and nobody wants
to keep them on the pegs.
The best price I've found for the HHK was from Mouser
at about $12 each. I've ordered a couple to use in my
comic book. So, it will be a few days longer but I'm still
planning on getting it published.
Bob . . .
________________________________________________________________________________
From: | "Eric M. Jones" <emjones(at)charter.net> |
Subject: | Re: 80 Amp Shunt |
>Does anyone know where to buy a 80amp/50mv shunt for an Electronics
>International
>volt/amp meter. I bought a used digital meter at Oshkosh and it did not
>have
>the shunt. I have found 50 and 75 amp from a marine supply but not the 80
>amp version. Thanks. John Lundberg Los Angeles, CA
Bob is right, you could get away with something close. But if you wanted to
use the 75A/50mV shunt, converting it to an 80A/50mV shunt is easy.
Calculations:
50mV / 80A = 0.625 milliOhms=Rt. (the shunt you need).
50mV / 75A = 0.625 milliOhms=Rq (the shunt you can get).
Rp=resistor to be put in parallel with the 75A Rq shunt to equal Rt, the
shunt you need.
Rt= 1/Rp+1/Rq (watch those p's and q's....math humor)
Rp=10.1524390 milliOhms.....more math humor, this stuff cracks me up! Okay
just use a 10 milliOhm resistor in parallel with the 75A shunt and you'll be
right on the money.
Regards,
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge MA 01550-2705
(508) 764-2072
"Mankind faces a cross-roads.
One path leads to despair and utter hopelessness.
The other, to total extinction.
Let us pray we have the wisdom to choose correctly."
--Woody Allen
________________________________________________________________________________
Subject: | Cage horizon when powering up ? |
Hi Bob and all,
We're using an "always hot" AIM electrical horizon. As soon as the
master switch is on the gyros start spinning.
A buddy (who is also a test pilo)t advised us to always cage the horizon
prior to flipping on the master switch. This is supposed to provide a
longer service life.
What is your opinion ? Is this advice worth a line in the start up check
list, or is it just another hangar tale ?
Thanks,
Regards,
Gilles Thesee
Grenoble, France
________________________________________________________________________________
From: | "Stein Bruch" <stein(at)steinair.com> |
Subject: | Re: Wire selection |
Ernest,
Couple things. I checked with a few distributors/mfgrs very quickly this
morning and like I said before, the cost does increase significantly in
multi-stranded cables of AWG18. It appears that for something like 4
conductor AWG18 cable, you can expect to pay between $1.70-$4.00 per foot
(depending on where you get it and the specs of the wire). That's over TEN
to TWENTY TIMES more expensive than buying the wire individually at around
$.15/ft for single conductor.
Now about the weight. I couldn't easily find the weight of the
multi-condutor cable, but single cables are a pretty good comparision.
AWG18 by itself weighs somewhere around 7 lbs per 1K'. AWG18 single
conductor shielded weighs somewhere around 16lbs per 1K'. Once again, that's
over double. You can expect the 4 conductor to increase, but not linearly.
It will weigh a good bit more than just running 4 wires.
The protection of the extra coating and shield is pretty much a mute point.
If you run your wires through bushings/grommets/etc.., they'll outlast the
airframe.
As far as "hours spent tying together" bundles....well....not many people
actually still tie bundles together. Heck, even the brand new airbuses come
from the factory with zip ties now, which are really quick. Next, if you do
have multi-strands of wire that need managing, put them in a "snakeskin" or
expandable sleeve. It's cheap and you can route them anywhere you want.
Your desires are good, and you reasoning is ok, but I'm afraid it's just not
what you'll end up doing. I'm afraid you'll find out that in reality,
you'll rarely actually run the entire 4 AWG18 cables from point A to point
B. You'll certainly want to pick off some of the conductors somewere, and
with shielded cable that's basically an impossibility or extremely
difficult. The wings might be one of the few spots where this would work,
but the fuselage has things placed all over, no matter what kind of plane
you're building.
I'm not trying to flame you here or be judgemental, just that I've built and
worked on a lot of airplanes from Cubs to 747's, and if there is a "better
way to build this moustrap", most people would be doing it. Homebuilders
are an ingenious group, and if something was easier and cheaper, they'd do
it. Not to mention I'm about the laziest guy out there, and like others I'm
always looking for a way to save time. I'm afraid this just isn't one of
those areas.
Anyway, if you do decide to move forward with this I won't chastise you,
I'll be glad to support you and help you out in any way I can. That being
said, I don't know of many retail outlets that have that AWG18 4 conductor
wire available, and most of the distributors want you to buy at least 1,000
feet of it to stay in the cheaper price ranges. If you want a decent sized
quantity (over 500'), I can help you find it and will be glad to do so even
given my personal thoughts on the situation.
Have a great week,
Stein.
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Ernest
Christley
Subject: AeroElectric-List: Re: Wire selection
Ok, multiple strands to increase capacity is not applicable to light
aircraft. I can easily see the safety issues.
I also agree that 18AWG for the "bird's nest behind the panel" would
make for a difficult work environment. I'll need to drop down to 22AWG
for most of that.
Furthermore, I agree that using a multistranded cable will increase
weight somewhat. I believe the weight is offset by the safety of an
additional jacket for the wire, the clean look of the installation, and
the simplicity of running the wire. It is just easier to make a cable
go where you want it to, vs several individual wires that you just spent
hours tying together.
Someone mentioned cost. The cable I'd like to have would be more
expensive, but not significantly so. If you count the time tying
together individual wires, the cable could be considered cheaper. But,
all told, I don't see enough of a difference to really make an argument
either way.
So, Stenair has a fine selection of aircraft wire and cable in all sorts
of multi-colored goodness. But their cable is only available in 22AWG.
Does anyone have a source of aircraft wire with a greater selection?
--
,|"|"|, |
----===<{{(oQo)}}>===---- Dyke Delta |
o| d |o www.ernest.isa-geek.org |
________________________________________________________________________________
From: | "B Tomm" <fvalarm(at)rapidnet.net> |
Subject: | Re: Wire selection |
Steinair HAS pretty much any gauge of wire you will need. They are great to
deal with too.
Bevan
RV7A fuse/finish/wiring/plumbing....
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Ernest
Christley
Subject: AeroElectric-List: Re: Wire selection
-->
Ok, multiple strands to increase capacity is not applicable to light
aircraft. I can easily see the safety issues.
I also agree that 18AWG for the "bird's nest behind the panel" would make
for a difficult work environment. I'll need to drop down to 22AWG for most
of that.
Furthermore, I agree that using a multistranded cable will increase weight
somewhat. I believe the weight is offset by the safety of an additional
jacket for the wire, the clean look of the installation, and the simplicity
of running the wire. It is just easier to make a cable go where you want it
to, vs several individual wires that you just spent hours tying together.
Someone mentioned cost. The cable I'd like to have would be more expensive,
but not significantly so. If you count the time tying together individual
wires, the cable could be considered cheaper. But, all told, I don't see
enough of a difference to really make an argument either way.
So, Stenair has a fine selection of aircraft wire and cable in all sorts of
multi-colored goodness. But their cable is only available in 22AWG.
Does anyone have a source of aircraft wire with a greater selection?
--
,|"|"|, |
----===<{{(oQo)}}>===---- Dyke Delta |
o| d |o www.ernest.isa-geek.org |
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: Cage horizon when powering up ? |
><Gilles.Thesee@ac-grenoble.fr>
>
>Hi Bob and all,
>
>We're using an "always hot" AIM electrical horizon. As soon as the
>master switch is on the gyros start spinning.
>A buddy (who is also a test pilo)t advised us to always cage the horizon
>prior to flipping on the master switch. This is supposed to provide a
>longer service life.
>What is your opinion ? Is this advice worth a line in the start up check
>list, or is it just another hangar tale ?
>
>Thanks,
>Regards,
I've not heard this before. I'll call some instrument shops
and ask. I had an airplane in my rental fleet where we
recommended caging the gyro for parking and uncaging at
startup to speed up erection times . . . this was a suggestion
of the aircraft's owner. Never did test the premise to
see if it made a difference. Was this a new gyro? What does
the manufacturer suggest in the installation data?
I don't think we've got a single airplane in the club that
even offers the manual caging capability. My initial reaction
is that it's probably more myth than fact.
Bob . . .
________________________________________________________________________________
Subject: | Re: Cage horizon when powering up ? |
>
> I've not heard this before. I'll call some instrument shops
> and ask. I had an airplane in my rental fleet where we
> recommended caging the gyro for parking and uncaging at
> startup to speed up erection times . . . this was a suggestion
> of the aircraft's owner. Never did test the premise to
> see if it made a difference. Was this a new gyro? What does
> the manufacturer suggest in the installation data?
>
> I don't think we've got a single airplane in the club that
> even offers the manual caging capability. My initial reaction
> is that it's probably more myth than fact.
>
>
Bob,
Thank you for responding.
I've got the impression that the manual knob is rather for erecting than
caging. I believe the rationale behind my buddy's advice is that by
erecting the gyro before startup we might relieve the delicate gimbals
and gizmos inside.
We bought the unit used from a helicopter broker, and it came with only
a wiring sheet.
I'd be much interested in further advice.
Thanks again,
Regards,
Gilles Thesee
Grenoble, France
________________________________________________________________________________
From: | owner-aeroelectric-list-server(at)matronics.com |
Subject: | Re: degaussing (demagnetizing) my roll bar |
Mickey,
I checked my weldments (rollbar and weldment behind pilot - forgot its name)
with an old fashioned very cheap needle compass, it does indeed move
substantially when close to the welds, and on some other locations. To do
this, I needed to be within 1 to 3 inches of the area. A foot from the
weldment did not deflect the compass. If you were to hang the compass from
the top of the roll bar, I think that you might have an issue, however if
you were to use a panel mounted compass, rollbar magnetization would most
probably not be an issue. My 2cents.
Take care,
Michele Delsol
RV8 very slow build fuselage
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-
> aeroelectric-list-server(at)matronics.com] On Behalf Of Mickey Coggins
> Sent: Friday, September 16, 2005 8:16 PM
> To: aeroelectric-list(at)matronics.com
> Subject: Re: AeroElectric-List: Re: degaussing (demagnetizing) my roll bar
>
> matronics(at)rv8.ch>
>
> > Eliminating magnetization is a process of scrambling the domains by
> > alternating the magnetic field while slowly reducing the field to zero.
> A
> > spool of wire, and a variable output transformer (variac) are the tools
> you
> > need; but how much and where is your individual experiment.
>
> Hi Eric,
>
> Thanks for the info. Do you think it's a waste of time to do this?
>
> Thanks,
> Mickey
>
> --
> Mickey Coggins
> http://www.rv8.ch/
> #82007 finishing
>
>
>
>
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Choices, choices, choices . . . |
>Bob:
>
>I am a long time student of yours and have read the book. I am about half
>way through an RV10 project.
>
>The folks who will build the panel and I have been discussing bus
>architecture. This will be an all electric panel and probably a
>non-electrically dependent engine.
>
>They are suggesting and I agree that two alts (60 and SD 20) and B& C
>controllers along with a single battery will be a good choice.
>
>They are also suggesting that both alternators can power the main bus and
>avionics busses simultaneously. (I know they still like an avionics bus).
>They propose setting the main alternator contoller at 14.2 or so and the
>back up SD20 a volt or so lower. Along with this they wire waring lights
>that alert steady when bus voltage drops to the backup level or below and
>flashes if the load should exceed 20 amps thereby alerting the pilot to
>reduce the loads.
>
>This architecture seems similar to Z13 without the alternate feed path and
>diode.
Actually Z-12
>Can this be done safely in your opinion? If so, what downside do you see
>in eliminating the endurance bus and alternate feed path for it.
>
>Thanks for your advice.
There is nothing UNsafe about any of the architectures that
have flown on aircraft since day-one as long as the pilot
understands system limitations and is prepared to deal with
failures in an educated and pre-planned manner.
A system with all the bells and whistles in the world is
only marginally "safer" than a J-3 with a wind generator
and flooded battery if the pilot is unable or unwilling
to make good choices about how he uses this equipment,
the environments into which he flies and when to "call
it a day".
The architecture being described by your panel shop is
equal to that being installed in hundreds of certified
ships (Z-12 with an avionics bus instead of an endurance
bus). But that's the opinion of someone who will never
be called upon to plan and skillfully execute a mission
with your aircraft. He/she will never have to deal with
whatever levels of risk presented by the choice of
hardware and how it's all wired up.
My opinion is equally without value. You're the customer.
If you want to wire your airplane like a 1970 C-172
(I fly airplanes like that all the time) and can operate
it with confidence in the face of whatever risks of failure
are present, then it's a SAFE flight system of which the
airplane is only a small part and YOU are the critical
part.
The architectures offered in the 'Connection
are not about SAFETY but about OPTIONS. It's about
failure mode effects analysis and understanding what
is or is not a good thing to do when something breaks.
Modern alternators and well maintained batteries in
a C-172 architecture have a small fraction the risks
of leaving you in the dark compared to 50 years ago.
Anything you do above and beyond that only improves
on your ability to deal effectively with what are
already very tiny risks without having to "call it
a day" because something broke.
So, the best advice I can offer is don't let your
panel shop drive your decisions as a customer. They,
(like the List and the 'Connection) should be offering
OPTIONS along with lucid explanations as to features
each option offers. Ultimately, you need to decide
which options are most useful whereupon you as
the CUSTOMER tells your SUPPLIER what it is you
want to purchase.
Bob . . .
________________________________________________________________________________
Subject: | Maxi In-line Source |
I found the maxifuse inline holder here:
http://racepartsolutions.com/products.asp?pg=9
Nice guy to deal with. I asked to keep the shipping cost down and he
just tossed it in an envelope and charged me $2. It got here (MN) in
2 days.
Pete
________________________________________________________________________________
From: | "Rodney Dunham" <rdunhamtn(at)hotmail.com> |
Subject: | VR for PM Alternator |
I've just purchased a Jabiru 3300 powered OBAM sky skorcher project. 90%
down, 90% to go.
The Jab comes with a "solid state" voltage regulator. I understand that the
PM Alternator (I think they call it a generator) was initially 3 phase but
Jabiru changed to single phase because it was eating VRs. What's the
difference?
Since I have become a devotee of the Connection I have wired a Rotax 912UL
powered sky skorcher with its Ducati ignition and VR with the predictable
good results. I used architecture almost identical to Z-20, except for the
LV warn system. It wasn't on the "small Rotax system" at the time.
My question is this: Should I just go ahead and use the stock VR and add
OVR/crowbar protection and LV warn as per Z-20 OR is there a VR out there
for PM alternators with built-in OVP, LVW and temp compensation?
My battery, battery contactor, starter contactor and VR are all mounted
close to each other on the firewall inside the engine compartment in a
tightly cowled airplane. It was that way when I bought the project.
RDunham,MD.
________________________________________________________________________________
From: | "Jim Jewell" <jjewell(at)telus.net> |
Subject: | Re: degaussing (demagnetizing) my roll bar |
I do not recall seeing this solution being suggested;
I found my roll bar to be mildly magnetic and sought to eliminate the
magnetism. On the suggestion of a friend. I took the roll bar to the non
destructive testing division of our local aero engine rebuild shop. They put
that nasty magnetism to death in about five minutes, four of which involved
set up time to carry out the industrial strength version of the death by
electrocution described below.
The good folks did the deed for a smile and a thankyou.
Jim in Kelowna - the wings are painted
(snip)
> Eliminating magnetization is a process of scrambling the domains by
> alternating the magnetic field while slowly reducing the field to zero.
> A
> spool of wire, and a variable output transformer (variac) are the tools
> you
> need; but how much and where is your individual experiment.
________________________________________________________________________________
From: | Speedy11(at)aol.com |
Subject: | Re: 80 Amp Shunt |
In a message dated 09/23/05 3:08:11 AM Eastern Standard Time,
aeroelectric-list-digest(at)matronics.com writes:
>Does anyone know where to buy a 80amp/50mv shunt for an Electronics
>International
>volt/amp meter. I bought a used digital meter at Oshkosh and it did not have
>the shunt. I have found 50 and 75 amp from a marine supply but not the 80
>amp version.
Do I presume correctly that the instrument is intended to
read 0-100% as a loadmeter? I.e., 50mv = 100 on instrument?
If so, then sizing the shunt to the alternator is the
appropriate thing to do. 80A is a bit of an odd size
but shunt fab shops can built to suit. If you can find
a shunt just over 80A, like 100A, it's easy to re-calibrate
it by cutting down the shunt element with a file. I can
do it for you if you can't find an exact 80. Also, you could
consider using the 75A shunt . . . it would simply "derate"
your alternator by 5A.
You can buy 80 Amp, 50mv shunts for $25 from B&C at
http://www.bandcspecialty.com/cgi-bin/ez-catalog/cat_display.cgi?15X358218. Just select the size you
need.
Stan Sutterfield
________________________________________________________________________________
From: | Richard Tasker <retasker(at)optonline.net> |
Subject: | Re: degaussing (demagnetizing) my roll bar |
This is probably not permanent magnetism of the rollbar but just the
fact that a potentially magnetic material (steel in this case) distorts
the earth's magnetic field in the vicinity of the rollbar and thereby
causes the compass needle to point in a direction not entirely aligned
with the earth's normal magnetic field alignment. This is why any piece
of avionics that uses a magnetometer (electronic compass) cautions you
to place it far away from any steel.
Lines of magnetic of force tend to (will) take the easiest path to
connect from the north pole to the south pole. Any potentially magnetic
material (whether it is magnetized or not) will provide a much easier
path than air. When this happens, the compass still aligns with the
resultant lines of force - but the lines of force no longer align with
what is expected.
If the roll bar is actually magnetized then the effect is typically much
more pronounced. A magnetized rollbar likely has a much greater
magnetic field than the earth.
The only way I know of to determine which of the two above cases is
causing the compass to move, aside from using gigantic Helmholtz coils,
is to rotate the rollbar (or entire plane) around the compass rose,
while holding the compass in the same position relative to the rollbar
and observe the compass needle. If the rollbar is magnetized the needle
will likely continue to point to roughly the same direction relative to
the rollbar. If it is just the distortion of the earth's magnetic
field, then the compass will rotate as the rollbar is rotated.
None of this is particularly pertinent except one should understand
that, just because a compass needle moves in the vicinity of a piece of
steel, the steel is not necessarily magnetized - so demagnetizing it in
that case would have no effect.
My $0.02...
Dick Tasker
owner-aeroelectric-list-server(at)matronics.com wrote:
>
>Mickey,
>
>I checked my weldments (rollbar and weldment behind pilot - forgot its name)
>with an old fashioned very cheap needle compass, it does indeed move
>substantially when close to the welds, and on some other locations. To do
>this, I needed to be within 1 to 3 inches of the area. A foot from the
>weldment did not deflect the compass. If you were to hang the compass from
>the top of the roll bar, I think that you might have an issue, however if
>you were to use a panel mounted compass, rollbar magnetization would most
>probably not be an issue. My 2cents.
>
>Take care,
>Michele Delsol
>RV8 very slow build fuselage
>
>
>
>>-----Original Message-----
>>From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-
>>aeroelectric-list-server(at)matronics.com] On Behalf Of Mickey Coggins
>>Sent: Friday, September 16, 2005 8:16 PM
>>To: aeroelectric-list(at)matronics.com
>>Subject: Re: AeroElectric-List: Re: degaussing (demagnetizing) my roll bar
>>
>>matronics(at)rv8.ch>
>>
>>
>>
>>>Eliminating magnetization is a process of scrambling the domains by
>>>alternating the magnetic field while slowly reducing the field to zero.
>>>
>>>
>>A
>>
>>
>>>spool of wire, and a variable output transformer (variac) are the tools
>>>
>>>
>>you
>>
>>
>>>need; but how much and where is your individual experiment.
>>>
>>>
>>Hi Eric,
>>
>>Thanks for the info. Do you think it's a waste of time to do this?
>>
>>Thanks,
>>Mickey
>>
>>--
>>Mickey Coggins
>>http://www.rv8.ch/
>>#82007 finishing
>>
>>
>>
>>
>>
>>
>>
>
>
>
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Wiring details for Van's IR Alternator? |
Had two folks call me in the last two days asking about
what to do with the three wires that come out of the connector
on Van's current 60A alternator offering.
Does anyone have that data they can share? Thanks!
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: Maxi In-line Source |
><pete.howell@gecko-group.com>
>
>
>I found the maxifuse inline holder here:
>
>http://racepartsolutions.com/products.asp?pg=9
>
>Nice guy to deal with. I asked to keep the shipping cost down and he
>just tossed it in an envelope and charged me $2. It got here (MN) in
>2 days.
>
>Pete
Cool! Good data point Pete. Thanks!
Bob . . .
________________________________________________________________________________
From: | "F. ILMAIN" <f_ilmain(at)hotmail.com> |
Subject: | FMS 5000 and shadin Microflo-L |
Anyone has experience wiring a Microflo-L to a an FMS 5000 Loran ?
Would need the manual / diagram for the FMS 5000
What happened to ARNAV website ?
Thanks
Franck
________________________________________________________________________________
From: | "Steve Hunt" <stephen.hunt19(at)btinternet.com> |
Subject: | Re: Wiring details for Van's IR Alternator? |
Hi Bob,
I asked the same question last week. This was Van's reply. By this I take it
to mean that the red and green leads are the power to the fields and that
the "earth" lead (blue) is not used.
Steve
> The red and green should be connected and the blue is not used...
> the case of the alt. is EARTH (:>)
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckollsr(at)cox.net>
Subject: AeroElectric-List: Wiring details for Van's IR Alternator?
>
>
> Had two folks call me in the last two days asking about
> what to do with the three wires that come out of the connector
> on Van's current 60A alternator offering.
>
> Does anyone have that data they can share? Thanks!
>
> Bob . . .
>
>
>
________________________________________________________________________________
Subject: | Wiring details for Van's IR Alternator? |
From: | "Hinde, Frank George (Corvallis)" <frank.hinde(at)hp.com> |
The center terminal is not used (this is the voltage sensing terminal)
the left terminal (as you look at the back of the alt) Is the ignition
terminal. Right termainal is the L or lamp terminal commonly used to
detect if the thing is charging...I vaguely remember that Vans has you
join these two terminals together (I.e does not use a lamp)
Frank
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
Robert L. Nuckolls, III
Subject: AeroElectric-List: Wiring details for Van's IR Alternator?
-->
Had two folks call me in the last two days asking about what to do with
the three wires that come out of the connector on Van's current 60A
alternator offering.
Does anyone have that data they can share? Thanks!
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Wiring details for Van's IR Alternator? |
>
>
>The center terminal is not used (this is the voltage sensing terminal)
>the left terminal (as you look at the back of the alt) Is the ignition
>terminal. Right termainal is the L or lamp terminal commonly used to
>detect if the thing is charging...I vaguely remember that Vans has you
>join these two terminals together (I.e does not use a lamp)
>
>Frank
Hmmm . . . the folks are telling me that there are red, blue
and green pigtails on the supplied connector. I'd really be
interested in seeing a copy of Van's wiring diagram which
I presume is part of his wire kit and/or supplied with the
alternator.
Bob . . .
________________________________________________________________________________
From: | "Lorenz Malmstrm" <lm(at)viscomvisual.com> |
Subject: | Abwesenheitsnotiz - Out of Office Notice |
Ich bin ab dem 10. Oktober 2005 wieder im Bro erreichbar. In dringenden Fllen wenden
Sie sich bitte an unser Sekretariat (031 307 50 50).
I will be in my office again from October 10, 2005. Please contact our front desk
for urgent matters (031 307 50 50).
________________________________________________________________________________
From: | "Steve Hunt" <stephen.hunt19(at)btinternet.com> |
Subject: | Re: Wiring details for Van's IR Alternator? |
Bob,
from the reply received from Vans which I copied you I believe that the red
and green tails are connected to field supply and the blue is not used. As
shown on Van's drawing OP 10,
Rgds Steve
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckollsr(at)cox.net>
Subject: RE: AeroElectric-List: Wiring details for Van's IR Alternator?
>
>
>
>>
>>
>>The center terminal is not used (this is the voltage sensing terminal)
>>the left terminal (as you look at the back of the alt) Is the ignition
>>terminal. Right termainal is the L or lamp terminal commonly used to
>>detect if the thing is charging...I vaguely remember that Vans has you
>>join these two terminals together (I.e does not use a lamp)
>>
>>Frank
>
> Hmmm . . . the folks are telling me that there are red, blue
> and green pigtails on the supplied connector. I'd really be
> interested in seeing a copy of Van's wiring diagram which
> I presume is part of his wire kit and/or supplied with the
> alternator.
>
> Bob . . .
>
>
>
________________________________________________________________________________
From: | <gmcjetpilot(at)yahoo.com> |
Subject: | Re: Wiring details for Van's IR Alternator? |
The lamp should be installed as it is a fault light as well as a low volt light.
http://www.autoshop101.com/forms/alt_bwoh.pdf
The above ref will give you the wiring.
Logic of the internal IC voltage regulator uses the difference between the output
and remote sense to control and protect. With out the remote sense it will
ignore it and use the b-lead/ign voltage with some loss in control and protection.
If it was designed with remote sense than use the remote sense. I think some
Toyota's run the remote to the battery. G
Wiring details for Van's IR Alternator?
-->
Had two folks call me in the last two days asking about what to do with
the three wires that come out of the connector on Van's current 60A
alternator offering.
Does anyone have that data they can share? Thanks!
Bob . . .
________________________________ Message 12 ____________________________________
From: "Robert L. Nuckolls, III"
Subject: RE: AeroElectric-List: Wiring details for Van's IR Alternator?
>
>
>The center terminal is not used (this is the voltage sensing terminal)
>the left terminal (as you look at the back of the alt) Is the ignition
>terminal. Right termainal is the L or lamp terminal commonly used to
>detect if the thing is charging...I vaguely remember that Vans has you
>join these two terminals together (I.e does not use a lamp)
>
>Frank
Hmmm . . . the folks are telling me that there are red, blue
and green pigtails on the supplied connector. I'd really be
interested in seeing a copy of Van's wiring diagram which
I presume is part of his wire kit and/or supplied with the
alternator.
Bob . . .
---------------------------------
Click here to donate to the Hurricane Katrina relief effort.
________________________________________________________________________________
From: | "Tinne maha" <tinnemaha(at)hotmail.com> |
Subject: | Wire Size for E-Buss Alt Feed |
Hello Bob/List,
A load analysis of my E-buss gives a total of 3.0 amps in cruise flight. 17
ft from battery bus to switch as a wire lays (batt in tail.) An AWG 20 wire
over that distance gives a drop of 0.52 volts. AWG 18 gives 0.33 volt drop.
Figure Z-11 shows an AWG 16 wire (which I presume to be for a battery in
the front & shorter wire length) which gives a 0.2 volt drop.
In sizing other wires I've chosen those which give a drop of ~0.5 volts or
less. (Hence, I'm inclined to use the AWG 20 or 18) However, the only time
this particular wire will be in use is when the system has dropped from ~14
Volts to ~12 Volts. I also realize, when in use, this will be the one wire
holding my entire electrical system together when I need it most. Is this a
reason to choose a bigger wire? How should I go about sizing it?
Any suggestions will be appreciated. Thanks,
Grant
________________________________________________________________________________
Subject: | headset jack problem |
I'm having a problem with the headset jacks in my RV-6A. The jacks are
connected to a Garmin 340 audio panel.
This situation I have now is this: when I play music (ipod) through the
340 it sounds great, in stereo, from both sets of jacks, but when I
speak into the mic I only get right channel sound from the pilot jacks.
I get perfect sound from both channels when using the passenger jacks.
I have performed these tests with the jacks out of the panel to make
sure there isn't a grounding problem.
I have made sure that everything is exactly the same with both sets of
jacks. I replaced the mono headset jacks with stereo jacks on both
sides.
I have also checked continuity on all the wiring of both sets of jacks.
I have done this according to the headset/mic wiring instructions that
came with my stack and Garmin's pin diagram. I repeated this check
several times to make sure everything was right.
The stereo/mono switch on the headset (lightspeed) has no effect. I
have tried another headset and get the same result.
I have adjusted the squelch carefully to make sure that's not an issue.
It's almost as if the pilot squelch itself is the problem since the
music input comes through perfectly.
Can anyone suggest the next step in diagnosing this problem? I feel
like it's just another case of my doing something stupid but I'm at a
loss at this point to know what that might be. If I had access to
another 340 audio panel I'd try that but I don't have that option.
thanks,
Robert Dickson
________________________________________________________________________________
From: | "bob noffs" <icubob(at)newnorth.net> |
hi all,
my elec. turn coor. has a port with 3 female pins. the attachment that was supplied
that you attach the wires to is as long as my house[ well, almost]. the
turn coor. id too deep for my panel with this attachment. is there something
out there that is a right angle or is there another means to attach the wires?
i have an inch from the forward edge of the ort to my fuel tank.
thanks in advance, bob noffs
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: Wire Size for E-Buss Alt Feed |
>
>Hello Bob/List,
>
>A load analysis of my E-buss gives a total of 3.0 amps in cruise flight. 17
>ft from battery bus to switch as a wire lays (batt in tail.) An AWG 20 wire
>over that distance gives a drop of 0.52 volts. AWG 18 gives 0.33 volt drop.
> Figure Z-11 shows an AWG 16 wire (which I presume to be for a battery in
>the front & shorter wire length) which gives a 0.2 volt drop.
>
>In sizing other wires I've chosen those which give a drop of ~0.5 volts or
>less. (Hence, I'm inclined to use the AWG 20 or 18) However, the only time
>this particular wire will be in use is when the system has dropped from ~14
>Volts to ~12 Volts. I also realize, when in use, this will be the one wire
>holding my entire electrical system together when I need it most. Is this a
>reason to choose a bigger wire? How should I go about sizing it?
When the alternator is running, the bus rides at 13.8 to 14.6 volts, the
alternator is capable of unlimited supply of energy and you have some
"power to burn". When you're operating battery only, the range of voltage
drops to 12.5 down to 11.O volts. Further, the energy stored is finite
and limited. A design goal for lower voltage drop in the endurance
mode seems prudent.
Bob . . .
________________________________________________________________________________
From: | "Bill and Marsha" <docyukon(at)ptcnet.net> |
Can anyone tell me if a kt 78 xpdr will fit in a kt 76a tray
(not including the elect connector) which I know is different. Bill S.
________________________________________________________________________________
From: | "Eric M. Jones" <emjones(at)charter.net> |
Subject: | Re: degaussing (demagnetizing) my roll bar |
>This is probably not permanent magnetism of the rollbar but just the
>fact that a potentially magnetic material (steel in this case) distorts
>the earth's magnetic field in the vicinity of the rollbar and thereby
>causes the compass needle to point in a direction not entirely aligned
>with the earth's normal magnetic field alignment. This is why any piece
>of avionics that uses a magnetometer (electronic compass) cautions you
>to place it far away from any steel.
Richard proposes an interesting problem. Let's see if I can confuse the
issue (or not).
>Lines of magnetic of force tend to (will) take the easiest path to
>connect from the north pole to the south pole. Any potentially magnetic
>material (whether it is magnetized or not) will provide a much easier
>path than air. When this happens, the compass still aligns with the
>resultant lines of force - but the lines of force no longer align with
>what is expected...>>snipped
First of all--THERE ARE NO MAGNETIC LINES OF FORCE (Please forgive the
capitalization but this is an important point). This classroom-demonstration
illusion is caused by each iron filing becoming temporarily magnetized. This
is an "emergent property" like an ant colony or a card game. Physicists draw
field gradients which are orthogonal to "lines of force", and they make more
sense. And yes, the presence of iron distorts the field gradient.
Soft iron has "loose" domains (kind of like a herd of cows in a pasture),
that can be influenced into alignment easily, but don't stay there when
another influence comes along. Alloying the iron is like putting up fences
and barriers that tend to keep the cows aligned.
>None of this is particularly pertinent except one should understand
>that, just because a compass needle moves in the vicinity of a piece of
>steel, the steel is not necessarily magnetized - so demagnetizing it in
>that case would have no effect. My $0.02...Dick Tasker
Dick is right, ferromagnetic materials and magnetized materials can be
confused. But determining if the roll bar is magnetized is not so hard.
Experiment on the cans of food in your larder. Note that a
ferromagnetic-material can, can attract either end of the compass needle
equally, but is biased if the can is magnetized. The hard part is finding
something that is NOT already magnetized--since just sitting around in the
Earth's magnetic field magnetizes ferromagnetic materials. The roll bar is
100% certain to be somewhat magnetized. Whether or not this is a problem
depends on your philosophical biases.
And don't forget you have compensating magnets inside the compass. The
compensators are reversed in compasses used in the southern hemisphere.
That's why compass binnacles allow holders to be rotated 180 degrees when
you pass over the equator.
Like all things, there is much more to say about magnetism, but it may
interest some readers that submarines in WWII were demagnetized to avoid
magnetic mines (which responded to magnetized hulls, not ferromagnetic
materials). The subs were wrapped with cables approximately six feet apart
that were pulsed with DC currents of 3000 amps, then polarity reversed and
pulsed with a smaller current until the last current pulse was only 5 amps.
Regards,
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge MA 01550-2705
(508) 764-2072
Here is Eric's Easy Science Lesson for the Day.
1) There are no electrons, at least in any real sense that you can observe
or demonstrate. Nobody has ever seen an electron.
2) There are no magnetic lines of force.
3) There is no inertia. (I have unsuccessfully argued this with physics book
writer Paul Hewitt). There is only mass and momentum and energy--sort
of--but it's not so simple as one thinks.
4) There are no solids in the universe. There's not even a suggestion of a
solid. ( R. Buckminster Fuller)
5) There are no absolute continuums. ( R. Buckminster Fuller)
6) There are no surfaces. ( R. Buckminster Fuller)
7) There are no straight lines. ( R. Buckminster Fuller)
8) Concepts of time and space are doomed (okay, this is a little complicated
but Einstein and Witten both agree on this).
9) And what the heck--Everything you know is wrong, too!
________________________________________________________________________________
From: | <gmcjetpilot(at)yahoo.com> |
Subject: | Re: Wiring details for Van's IR Alternator? (how to) |
I know Van's does not show connecting the alternator's (L) light up and connecting
the sense wire to the IGN wire. Here are some reasons you may want to connect
all three wires up as planned. There are one wire alternators but they have
some draw backs. By wiring Van's 60 amp as some suggest or discribed, essentially
makes it an one wire alternator.
http://www.madelectrical.com/electricaltech/onewire-threewire.shtml
---------------------------------
Click here to donate to the Hurricane Katrina relief effort.
________________________________________________________________________________
From: | "Glen Matejcek" <aerobubba(at)earthlink.net> |
Subject: | FW: Wiring details for Vans 60A alternator |
Glen Matejcek
aerobubba(at)earthlink.net
----- Original Message -----
From: Glen Matejcek
Subject: Wiring details for Vans 60A alternator
Hi Bob et al-
I've been off the list for a while and missed your original request for alternator
info. As it happens, I've been doing some research into this very topic of
late, and have made some interesting discoveries. First, Van's input was that
the exact color of the wires in the 3 wire plug changes now and then, and shouldn't
be used as a basis for wiring the alternator up. They did say that the
3 spade connectors in the plug assembly are in a 'pi' configuration, 2 blades
being parallel and one at right angles. The odd blade is not used, and the
2 parallel ones are tied together and run to the ALT switch.
Second, I found a high volume overhauler who seemed very knowledgeable and willing
to share his expertise. According to him, that top spade in the pi, the
one at right angles, in the case of vans specific unit (Vans #14684, ND unit #
14824) is the 'D' terminal, 'D' as in 'dummy'. It's not connected to anything.
The left leg of the pi is the 'I' terminal. 'I' stands for 'Ignition', which
is what that terminal connects to. The right leg of the pi is 'L' for 'Light',
and connects to the ALT idiot light.
The most interesting thing is that the labelling of the terminals has only to do
with the wire routing, and not much to do with their function. The 'I' terminal
is actually the voltage sense input, and in a car would be fed anytime the
ignition was on. The 'L' terminal is the 'ON' signal input. It would be connected
to the 'run' position of the ignition switch via the idiot light lamp.
With the ignition switch in 'run', a +V signal with little or no current turns
the ALT on, but won't light the lamp. With the ALT inop for any reason, the
'L' terminal goes to ground and the lamp illuminates. Curiously, this implies
that a failure of the ALT lamp will cause the alternator to shut down, and
without the idiot light coming on. Last, removing the +V from the 'L' terminal
does shut the alternator down per it's spec.
Hope this info is useful-
Glen Matejcek
aerobubba(at)earthlink.net
________________________________________________________________________________
Subject: | Re: MAGNETO TIMING BUSS BOX PLANS |
While I think the kit information that was posted is most likely the best
option, I located a "how-to" article from the May 1992 issue of SPORT AVIATION,
page 64, that has a schematic on how to build one.
Personally, I am very fortunate to have a former field service engineer for
Slick Electro who has a hangar about 200 feet from mine!
HAPPY FLYING SAFELY,
Wally Hunt
Rockford, IL
RV-4 Finishing Kit
________________________________________________________________________________
From: | "william rumburg" <lancair403(at)earthlink.net> |
Subject: | Alternator Speed |
Alternator rpm = engine rpm X (engine pulley diameter/alternator pulley
diameter).
My Lycoming has the 7.5" (small) pulley and my alternator has a 2.75"
pulley, which I believe to be typical. This results in alternator speeds in
the 7,000 rpm range during cruise, which I believe to be excessive. A 4"
diameter pulley is available for my alternator, which would reduce it's
speed to the 4,000 rpm range and, I believe, produce full-rated output.
I spoke with Mark Landoll who told me that alternators typically require a
minimum of 1,000 rpm to produce a stable output, but he didn't know what
rpm is usually required to produce full-rated output. I believe it to be in
the 4,000 rpm range. He did agree that, while alternator bearings seem to
hold up well to high speeds, lower speeds would produce less stress and
vibration.
Is anyone on the LML knowledgeable of the alternator speed typically
required to produce full rated output?
Bill Rumburg
N403WR (Sonic bOOm)
________________________________________________________________________________
From: | "Dennis Johnson" <pinetownd(at)volcano.net> |
Subject: | Magnetized Roll Bar |
I must be missing something here regarding the magnetized roll bar. A compass
needle is a magnet and magnets are attracted to iron. So a compass needle will
always point towards the iron in the steel roll bar, whether it is magnetized
or not. Therefore using a compass is not a method to determine if the roll
bar is magnetized.
To determine if it is magnetized, why not put some non-magnetized iron filings
on it; if they stick, then it's magnetized, and if they don't it's not. (But
I suppose that opens up the issue of how do you determine that your iron filings
aren't magnetized. I suppose you could heat them to cherry red and then allow
them to cool immediately prior to the test?)
Note: I'm using the colloquial term "magnets are attracted to iron" because it
is accurately descriptive of the current situation, knowing that a more rigorous
physics explanation would be different. But the difference would not be relevant
to this discussion.
Dennis Johnson
Lancair Legacy #257
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: Alternator Speed |
>
>
>Alternator rpm = engine rpm X (engine pulley diameter/alternator pulley
>diameter).
>My Lycoming has the 7.5" (small) pulley and my alternator has a 2.75"
>pulley, which I believe to be typical. This results in alternator speeds in
>the 7,000 rpm range during cruise, which I believe to be excessive. A 4"
>diameter pulley is available for my alternator, which would reduce it's
>speed to the 4,000 rpm range and, I believe, produce full-rated output.
>I spoke with Mark Landoll who told me that alternators typically require a
>minimum of 1,000 rpm to produce a stable output, but he didn't know what
>rpm is usually required to produce full-rated output. I believe it to be in
>the 4,000 rpm range. He did agree that, while alternator bearings seem to
>hold up well to high speeds, lower speeds would produce less stress and
>vibration.
>Is anyone on the LML knowledgeable of the alternator speed typically
>required to produce full rated output?
Here's a typical output current curve for an
automotive alternator. The population of
mfgrs and part numbers will "wiggle" a bit
from this curve but it's probably plus or minus
10 percent for the whole lot.
http://www.aeroelectric.com/Pictures/80A_OutCurve.gif
It depends on what you want . . . and what the tradeoffs
are. If you'd like to have good output at ramp idle and
taxi speeds (most folk really like the low speed
capability in both cars and airplanes), then leave the
pulley small. If you're worried about bearing and brush
life, know that B&C has been selling the L40/L60 series
machines for about 15 years with thousands of units in
service. The first wearout in B&C history arrived back
in Newton about a year ago . . . needed brushes . . .
after 2200 hours in service. These alternators run nicely
at over 10,000 rpm in cruise with no evidence of having
"over stressed" anything due to the high speeds.
If it were my airplane, I'd leave the small pulley
on . . . especially if your ring gear pulley is smaller
than most . . . you've already taken a hit on pre-flight
output capability.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: Magnetized Roll Bar |
>
>
>I must be missing something here regarding the magnetized roll bar. A
>compass needle is a magnet and magnets are attracted to iron. So a
>compass needle will always point towards the iron in the steel roll bar,
>whether it is magnetized or not. Therefore using a compass is not a
>method to determine if the roll bar is magnetized.
Kinda . . . sorta. If you know how to "probe" a magnetized
object with a small compass, you can look for and perhaps
identify two or more "poles". It's true that any ferrous
material will attract EITHER end of a compass needle.
>To determine if it is magnetized, why not put some non-magnetized iron
>filings on it; if they stick, then it's magnetized, and if they don't it's
>not. (But I suppose that opens up the issue of how do you determine that
>your iron filings aren't magnetized. I suppose you could heat them to
>cherry red and then allow them to cool immediately prior to the test?)
Most folks in the business use a linear hall effect device
or other detector of magnetic fields.
>Note: I'm using the colloquial term "magnets are attracted to iron"
>because it is accurately descriptive of the current situation, knowing
>that a more rigorous physics explanation would be different. But the
>difference would not be relevant to this discussion.
The magnetized structure threads have popped up and gone
dozens of times in the various interest groups for years. Having
conducted magnetic effects tests in the lab for decades using
plain ol' wet compasses, I can tell you that it takes one
hell of a magnet to have much effect on a compass at typical
separations between structure and compass. The last (and only)
case I worked on an airplane was an SD20 install on Bonanzas. Turning
the standby alternator on deflected the compass as much as 20
degrees on some headings . . . . this was with the compass mounted
on the glare shield deck. Just moving the compass up to
an already certified windshield mount reduced the effects to
2 degrees or less worst case. This was a movement of perhaps
8" vertically in the airplane.
I experimented with some magnetic shielding for the rear
of the SD20 and it didn't take much iron to corral the loose
field flux but it would have required a re-certification
of the SD20 installation. So, the lesser to two evils was
move the compass a little bit.
I cite this example to show (1) how the only time I've
seen a problem involved a very strong magnetic source and
(2) very little repositioning reduced the problem to
insignificant levels. Magnetic fields like to stay very
close to home and do not venture out far . . . likelihood
of an inadvertent magnetization of structure being a problem
is small . . . and reducing it to insignificance shouldn't
be difficult.
Bob . . .
________________________________________________________________________________
From: | Frank & Phyllis <frank.phyllis(at)mindspring.com> |
Is a ground plane necessary for an ELT antenna? I noticed some builders
have mounted the antenna inside the tube/fabric fuselage with only a
small bracket for the antenna? Why wouldn't a ground plane be needed?
Frank
________________________________________________________________________________
From: | "Eric M. Jones" <emjones(at)charter.net> |
Subject: | Re: Magnetized Roll Bar |
>I must be missing something here regarding the magnetized roll bar. A
>compass
>needle is a magnet and magnets are attracted to iron. So a compass needle
>will
>always point towards the iron in the steel roll bar, whether it is
>magnetized
>or not. Therefore using a compass is not a method to determine if the roll
>bar is magnetized.
>To determine if it is magnetized, why not put some non-magnetized iron
>filings
>on it; if they stick, then it's magnetized, and if they don't it's not.
>(But
>I suppose that opens up the issue of how do you determine that your iron
>filings
>aren't magnetized. I suppose you could heat them to cherry red and then
>allow
>them to cool immediately prior to the test?)
>Note: I'm using the colloquial term "magnets are attracted to iron"
>because it
>is accurately descriptive of the current situation, knowing that a more
>rigorous
>physics explanation would be different. But the difference would not be
>relevant
>to this discussion. Dennis Johnson Lancair Legacy #257
Hi Dennis,
I urge interested parties to experiment with soup cans, etc. (I'm not
kidding). It is quite simple to determine if the metal can (or roll bar) is
magnetized, since a non-magnetized ferromagnetic material will cause the
same reaction with either the north or south end of the compass needle. But
a compass needle will be wildly biased and behave differently depending on
which end of the compass needle points to a magnetized metal part.
Roll bars can be magnetized slowly just by sitting around, or quickly by a
lightning strike, or a sudden current surge in the airframe ground, or it
got that way in welding or forming. Like termites in lumber, sometimes you
just buy the material that way.
Regards,
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge MA 01550-2705
(508) 764-2072
"Nothing is too wonderful to be true."
James Clerk Maxwell, discoverer of electromagnetism
"Too much of a good thing can be wonderful."
Mae West, discoverer of personal magnetism
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
>
>
>Is a ground plane necessary for an ELT antenna? I noticed some builders
>have mounted the antenna inside the tube/fabric fuselage with only a
>small bracket for the antenna? Why wouldn't a ground plane be needed?
>Frank
Almost any conductor will radiate and, therefore, can be called
an "antenna" too. There's been more than one individual craft some
form antenna that (1) departed from the best we know how to do
and/or (2) was placed in service without exploring its characteristics
with instrumentation and reported "it works great for me."
Bottom line is that the best we know how to do has been understood
for nearly a century and yes, your skepticism is valid. Folks can
probably hear his triggered ELT across the field but it's not
going to work as well as it might with a more considered
and well crafted installation.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
>
>hi all,
> my elec. turn coor. has a port with 3 female pins. the attachment that
> was supplied that you attach the wires to is as long as my house[ well,
> almost]. the turn coor. id too deep for my panel with this attachment. is
> there something out there that is a right angle or is there another means
> to attach the wires? i have an inch from the forward edge of the ort to
> my fuel tank.
> thanks in advance, bob noffs
It depends on what YOU are satisfied with. You can craft some very
short mating pins and solder wires to them that depart the joint
at right angles to the pin. Cover with heatshrink and retain with
some form of easily removed material . . . like hot glue.
I think this would stay in place nicely and accomplish what
you want. You'll want to avoid showing this to anyone else
on your field lest the have considerable fun at your
expense over the beer and pretzels.
Bob . . .
________________________________________________________________________________
From: | "Jim Jewell" <jjewell(at)telus.net> |
Subject: | Re: Alternator Speed |
Hi William,
I do not remember any comments or questions on the list about the
relationship between alternator pulley diameter and belt service life.
During the racing days of a past life we commonly ran engines well into the
7000 RPM range.
My guess is that the alternator likely exceeded twice that. Alternators
where standing up to that kind of use without much complaint.
Looking back now I wonder if we might have redirected at least some
percentage of horse power by using a larger pulley. Turning the alternator
above 12000 RPM most likely wastes energy as they don't seem to produce
usable added output approaching and or beyond that.
Bending the belt around a small pulley above 10,000 RPM most likely would
create heat that must reduce belt life.
Fan belts can take a lot of abuse. I just remembered a modified Corvair that
ate the occasional belt during hard runs. Corvairs had the worst fan belt
layout that I ever saw.
Turning the alternator at 7000 RPM while set up in cruse should not have
serious negative effects on the belt or the alternator with small pulley and
the low speed (idle) performance would be of benefit.
The large pulley might interfere with the cowling if you are an RV type.
happy flights,
Jim in Kelowna - installing windshield
----- Original Message -----
From: "william rumburg" <lancair403(at)earthlink.net>
Subject: AeroElectric-List: Alternator Speed
>
>
> Alternator rpm = engine rpm X (engine pulley diameter/alternator pulley
> diameter).
> My Lycoming has the 7.5" (small) pulley and my alternator has a 2.75"
> pulley, which I believe to be typical. This results in alternator speeds
> in
> the 7,000 rpm range during cruise, which I believe to be excessive. A 4"
> diameter pulley is available for my alternator, which would reduce it's
> speed to the 4,000 rpm range and, I believe, produce full-rated output.
> I spoke with Mark Landoll who told me that alternators typically require a
> minimum of 1,000 rpm to produce a stable output, but he didn't know what
> rpm is usually required to produce full-rated output. I believe it to be
> in
> the 4,000 rpm range. He did agree that, while alternator bearings seem to
> hold up well to high speeds, lower speeds would produce less stress and
> vibration.
> Is anyone on the LML knowledgeable of the alternator speed typically
> required to produce full rated output?
>
> Bill Rumburg
> N403WR (Sonic bOOm)
>
>
>
________________________________________________________________________________
From: | Ken <klehman(at)albedo.net> |
Subject: | Re: ectric-List: |
I picked up a used metal 90 degree connector from Wentworth but I'm
pretty sure it still stuck out at least an inch. It required joining the
wires as I didn't have spare pins that fit.
Ken
Robert L. Nuckolls, III wrote:
>
>
>
>
>>
>>hi all,
>> my elec. turn coor. has a port with 3 female pins. the attachment that
>>was supplied that you attach the wires to is as long as my house[ well,
>>almost]. the turn coor. id too deep for my panel with this attachment. is
>>there something out there that is a right angle or is there another means
>>to attach the wires? i have an inch from the forward edge of the ort to
>>my fuel tank.
>> thanks in advance, bob noffs
>>
>>
>
> It depends on what YOU are satisfied with. You can craft some very
> short mating pins and solder wires to them that depart the joint
> at right angles to the pin. Cover with heatshrink and retain with
> some form of easily removed material . . . like hot glue.
>
> I think this would stay in place nicely and accomplish what
> you want. You'll want to avoid showing this to anyone else
> on your field lest the have considerable fun at your
> expense over the beer and pretzels.
>
> Bob . . .
>
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: Alternator Speed |
>
>
>
> > Here's a typical output current curve for an
> > automotive alternator. The population of
> > mfgrs and part numbers will "wiggle" a bit
> > from this curve but it's probably plus or minus
> > 10 percent for the whole lot.
> >
> > http://www.aeroelectric.com/Pictures/80A_OutCurve.gif
> >
>
>Just a quick question - was this alternator putting out
>14.something volts the whole time, or does the voltage
>change with the alternator speed?
This is an output curve for current with a regulator
connected. Therefore, the voltage is constant at whatever
the regulator is set for. This shows that the minimum
speed for regulation is about 1000 rpm . . . 14v but
no current.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: Alternator Speed |
>
>Hi William,
>
>I do not remember any comments or questions on the list about the
>relationship between alternator pulley diameter and belt service life.
>During the racing days of a past life we commonly ran engines well into the
>7000 RPM range.
That's another trade-off. Suppose the smallest pulley on the
alternator produces some signs of wear on the belt at say,
250 hours . . . this is about 5 years in average life of
a light airplane. By this time, you've spent a lot of $ on plugs,
oil changes, probably a battery or two, maybe some tires. Yup,
EVERYTHING has a service life that may be extended and/or
reduced depending on the performance one expects.
Would you trade off better alternator performance at low engine
speeds for longer service life on a belt? It's certainly a
design goal to be considered.
>My guess is that the alternator likely exceeded twice that. Alternators
>where standing up to that kind of use without much complaint.
How many service hours per year would one expect from an
alternator in this application? Would it even be as many hours
as the average airplane (50 or so).
>Looking back now I wonder if we might have redirected at least some
>percentage of horse power by using a larger pulley. Turning the alternator
>above 12000 RPM most likely wastes energy as they don't seem to produce
>usable added output approaching and or beyond that.
>Bending the belt around a small pulley above 10,000 RPM most likely would
>create heat that must reduce belt life.
>Fan belts can take a lot of abuse. I just remembered a modified Corvair that
>ate the occasional belt during hard runs. Corvairs had the worst fan belt
>layout that I ever saw.
The differences in overall system losses between optimal belt
ratios for full alternator output at cruise and belt ratios
for not exceeding alternator max rpm in trade for better
taxi speed performances is calculable but difficult to actually
measure. A pilot would not perceived the difference in terms of
flight system performance.
>Turning the alternator at 7000 RPM while set up in cruse should not have
>serious negative effects on the belt or the alternator with small pulley and
>the low speed (idle) performance would be of benefit.
>
>The large pulley might interfere with the cowling if you are an RV type.
All these factors should be considered when crafting one's personal
list of design goals. Thanks for bringing them up!
Bob . . .
________________________________________________________________________________
From: | "Eric M. Jones" <emjones(at)charter.net> |
It should be said that residual magnetism is much less of a problem if the pilot
does not depend on the compass as the primary navigation instrument. In fact,
the compass is usually just used as a steering bearing. Since the upper winds
are usually just estimates, and nobody I know navigates with an E6B like they
teach in ground school--compasses are much less important nowadays.
For those who want to know more--the definitive available (and readable) work on
the subject is:
http://pollux.nss.nima.mil/NAV_PUBS/APN/Chapt-06.pdf
This addresses the needs of ships at sea, but it's all the same stuff.
Regards,
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge MA 01550-2705
(508) 764-2072
"Beaten paths are for beaten men."
-E. A. Johnston
________________________________________________________________________________
From: | Fiveonepw(at)aol.com |
Subject: | Belt replacement (was Alternator Speed) |
Would you trade off better alternator performance at low engine
speeds for longer service life on a belt?
>>>>
Which brings up something I don't recall seeing discussed here or on RV-list:
What is typical failure mode for belt and what is potential for/scope of
"collateral damage" in event of failure? How is belt condition best determined
and what is best practice for determining replacement interval?
Thanks- Mark Phillips
________________________________________________________________________________
From: | <bakerocb(at)cox.net> |
Subject: | Beechcraft Ground Power |
9/26/2005
Hello Old Bob and Other Beechcraft Experts, I fly in a 1988 Beechcraft
Sierra from time to time as an instructor and safety pilot.
This aircraft has a 24 volt electrical system with an external ground power
receptacle on the middle left side of the fuselage. This receptacle is round
with a post in the middle.
Recently when the owner sought to have external power applied by a local FBO
that services a wide variety of transient aircraft (including Pipers) the
FBO told the owner that they had no plug on their ground power cart that was
compatible with the Sierra's ground power receptacle.
We found that hard to believe and went searching for a compatible plug, or
an adapter that would allow a commonly available plug to be used in the
Sierra's receptacle. We initially assumed that the receptacle must be a
Piper type (round with a post in the middle), but after examining some Piper
type plugs on local ground power carts it appears that the Piper plug will
not fit that receptacle.
Further research has left us empty handed. A phone call to a Beechcraft
parts source said that that receptacle "was no longer supported".
So the questions are:
1) What is the story on the ground power receptacle on the Sierra? Is it a
maverick that Beechcraft came up with that is no longer supported by them or
compatible with commonly found FBO ground power cart plugs?
2) What is the best way to come up with a device that will allow use of the
commonly found plugs on FBO ground power carts?
Many thanks.
OC
________________________________________________________________________________
From: | "Fox5flyer" <morid(at)northland.lib.mi.us> |
Subject: | Solid State Gyros |
I'm in the market for an electric Artificial Horizon gyro. I'm not planning on
any hard IMC. I just want something to help with pitch and roll when I get into
a short term situation, like haze over the water.
The options I've found are the RC Allen (very expensive) and Falcon (about half).
Both are mechanical and provide no other information.
The other option is to go solid state with lots of information. There are the
Trutrack and Dynon units to name a couple. I don't have any experience with the
new solid state units at all. I'd like to keep my expenses under or around
$2500. Here are my questions.
1. Does anybody have any experience with the Falcon electric AH? Reliability?
2. Does anybody have any experience with any of the solid state units? Positive
or negative.
3. Do the solid state units provide the same accuracy as the mechanical units?
4. Are the solid state units reliable?
5. How do the solid state units work, pitch-roll-heading?
6. Other than those that I mentioned above, are there any others out there that
are worth persuing.
Thanks for any info offered.
Deke
Mikado MI
________________________________________________________________________________
From: | "Jeff" <jdalton77(at)comcast.net> |
Subject: | Re: Solid State Gyros |
Sporty's has a new OEM'd unit that looks good and isn't too expensive.
----- Original Message -----
From: "Fox5flyer" <morid(at)northland.lib.mi.us>
Subject: AeroElectric-List: Solid State Gyros
>
>
> I'm in the market for an electric Artificial Horizon gyro. I'm not
> planning on any hard IMC. I just want something to help with pitch and
> roll when I get into a short term situation, like haze over the water.
> The options I've found are the RC Allen (very expensive) and Falcon (about
> half). Both are mechanical and provide no other information.
> The other option is to go solid state with lots of information. There are
> the Trutrack and Dynon units to name a couple. I don't have any
> experience with the new solid state units at all. I'd like to keep my
> expenses under or around $2500. Here are my questions.
>
> 1. Does anybody have any experience with the Falcon electric AH?
> Reliability?
>
> 2. Does anybody have any experience with any of the solid state units?
> Positive or negative.
>
> 3. Do the solid state units provide the same accuracy as the mechanical
> units?
>
> 4. Are the solid state units reliable?
>
> 5. How do the solid state units work, pitch-roll-heading?
>
> 6. Other than those that I mentioned above, are there any others out
> there that are worth persuing.
>
> Thanks for any info offered.
>
> Deke
> Mikado MI
>
>
>
________________________________________________________________________________
From: | "Dave Morris \"BigD\"" <BigD(at)DaveMorris.com> |
Subject: | Re: Solid State Gyros |
The TruTrak impressed the heck out of me at Sun-N-Fun. One of their AH
units was sitting on the table with a single power cord running to it. I
picked it up and flipped it around and the horizon stayed stable no matter
how I tortured it. Very impressive, tiny little unit. No idea if it's
reliable or breaks or whatever. I predict that this stuff is going to keep
coming down in cost as the solid state sensors begin to invade GA cockpits.
Dave Morris
At 03:09 PM 9/26/2005, you wrote:
>
>
>I'm in the market for an electric Artificial Horizon gyro. I'm not
>planning on any hard IMC. I just want something to help with pitch and
>roll when I get into a short term situation, like haze over the water.
>The options I've found are the RC Allen (very expensive) and Falcon (about
>half). Both are mechanical and provide no other information.
>The other option is to go solid state with lots of information. There are
>the Trutrack and Dynon units to name a couple. I don't have any
>experience with the new solid state units at all. I'd like to keep my
>expenses under or around $2500. Here are my questions.
>
>1. Does anybody have any experience with the Falcon electric
>AH? Reliability?
>
>2. Does anybody have any experience with any of the solid state
>units? Positive or negative.
>
>3. Do the solid state units provide the same accuracy as the mechanical
>units?
>
>4. Are the solid state units reliable?
>
>5. How do the solid state units work, pitch-roll-heading?
>
>6. Other than those that I mentioned above, are there any others out
>there that are worth persuing.
>
>Thanks for any info offered.
>
>Deke
>Mikado MI
>
>
________________________________________________________________________________
From: | "Jim Baker" <jlbaker(at)telepath.com> |
Subject: | Solid state..... |
http://www.aircraftspruce.com/catalog/avpages/icarusefis.php
Jim Baker
580.788.2779
'71 SV, 492TC
Elmore City, OK
________________________________________________________________________________
From: | Phil Birkelbach <phil(at)petrasoft.net> |
Subject: | Re: Solid State Gyros |
Fox5flyer wrote:
>
>I'm in the market for an electric Artificial Horizon gyro. I'm not planning on
any hard IMC. I just want something to help with pitch and roll when I get
into a short term situation, like haze over the water.
>The options I've found are the RC Allen (very expensive) and Falcon (about half).
Both are mechanical and provide no other information.
>The other option is to go solid state with lots of information. There are the
Trutrack and Dynon units to name a couple. I don't have any experience with
the new solid state units at all. I'd like to keep my expenses under or around
$2500. Here are my questions.
>
>1. Does anybody have any experience with the Falcon electric AH? Reliability?
>
>2. Does anybody have any experience with any of the solid state units? Positive
or negative.
>
>
>
I love my Dynon. So far only 1.5 hours on it but others have had good luck.
>3. Do the solid state units provide the same accuracy as the mechanical units?
>
>
I would guess them to be better than the mechanicals. No precession to
worry about and frankly, they aren't mechanical. I have met very few
mechanical instruments that offered the same accuracy as their digital
counterparts although this comparison may be flawed.
>4. Are the solid state units reliable?
>
>
Ask me in a couple thousand hours. It's hard to argue with "no moving
parts" however. Dan C. has several hundred hours on his Dynon and I
think he still likes it.
>5. How do the solid state units work, pitch-roll-heading?
>
>
>
Don't understand the question. It works with accelerometers and rate
gyros. The Dynon displays pitch and roll on a digitally rendered horizon
and heading on a tape that scrolls across the top of the screen.
>6. Other than those that I mentioned above, are there any others out there that
are worth persuing.
>
>
Grand Rapids has a nice little unit. www.grtavioncs.com IIRC Also
check out Blue Mountain's offerings. There are also some PDA based
options but I can't remember the names of any of those.
>Thanks for any info offered.
>
>Deke
>Mikado MI
>
>
>
>
Godspeed,
Phil Birkelbach - Houston Texas
RV-7 N727WB - Phase I
http://www.myrv7.com
>
>
________________________________________________________________________________
From: | "Kingsley Hurst" <khurst(at)taroom.qld.gov.au> |
Subject: | Solid State Gyros |
> 6. Other than those that I mentioned above, are there any others out
there that are worth pursuing.
Deke
Another alternative is at
www.stratomaster(at)lightflying.com.au
I have no experience with them myself but will be looking hard at them
later on.
They are manufactured in South Africa.
The above link is to the Australian agent but I'm sure you have agents
in the US too.
Regs
Kingsley Hurst in Oz
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: Belt replacement (was Alternator Speed) |
>
>
> Would you trade off better alternator performance at low engine
> speeds for longer service life on a belt?
>
> >>>>
>
>Which brings up something I don't recall seeing discussed here or on RV-list:
> What is typical failure mode for belt and what is potential for/scope of
>"collateral damage" in event of failure? How is belt condition best
>determined
>and what is best practice for determining replacement interval?
>
>Thanks- Mark Phillips
Belts will show distinct signs of distress long before catastrophic
failure. Cracks, polished sides of the "V", and cords exposed
or hanging out are all reasons to consider replacement. Of course,
you have to pull the prop to replace a belt. I've seen airplanes
at airshows where a "spare" belt was installed over the prop
shaft and secured behind the ring gear pulley. The idea was
that a broken belt could be replaced by simply loosening the
alternator belt tightening brackets and slipping the new one
into place without removing the prop. I asked a few owners
of such aircraft if they'd ever taken advantage of this feature
or knew anyone else who had . . . none answered in the affirmative.
V-belts on aircraft are generally very lightly loaded. Alternators
draw less than 1 h.p. in cruise. Exposure to the elements while
parked probably represents a bulk of the stresses on a belt that
would reduce time in service. Poor tensioning practice can also
reduce life . . .
If a looksee and feel before flight passes muster on a quality
belt, it's going to still be there doing its job when you land.
Bob . . .
Buy good quality belts (Gates) and replace at first signs of
distress (which will be years of time and hundreds of hours
of flight) or at any time you happen to pull the prop, put a new
belt on. Like batteries, well monitored and maintained belts
are VERY low on your list of concerns for finding yourself
"up there" and wishing you were "down here".
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: Beechcraft Ground Power |
>
>9/26/2005
>
>Hello Old Bob and Other Beechcraft Experts, I fly in a 1988 Beechcraft
>Sierra from time to time as an instructor and safety pilot.
>
>This aircraft has a 24 volt electrical system with an external ground power
>receptacle on the middle left side of the fuselage. This receptacle is round
>with a post in the middle.
>
>Recently when the owner sought to have external power applied by a local FBO
>that services a wide variety of transient aircraft (including Pipers) the
>FBO told the owner that they had no plug on their ground power cart that was
>compatible with the Sierra's ground power receptacle.
>
>We found that hard to believe and went searching for a compatible plug, or
>an adapter that would allow a commonly available plug to be used in the
>Sierra's receptacle. We initially assumed that the receptacle must be a
>Piper type (round with a post in the middle), but after examining some Piper
>type plugs on local ground power carts it appears that the Piper plug will
>not fit that receptacle.
>
>Further research has left us empty handed. A phone call to a Beechcraft
>parts source said that that receptacle "was no longer supported".
>
>So the questions are:
>
>1) What is the story on the ground power receptacle on the Sierra? Is it a
>maverick that Beechcraft came up with that is no longer supported by them or
>compatible with commonly found FBO ground power cart plugs?
>
>2) What is the best way to come up with a device that will allow use of the
>commonly found plugs on FBO ground power carts?
Hmmmm . . . I used to fly a Sierra but never had occasion to use
or even look at the ground power receptacle. The Beech flying
club has some Sundowners which are almost certain to have the
same receptacle. I'll see what they've got and then bug my friends
over in customer support about details.
Bob . . .
________________________________________________________________________________
From: | "Rodney Dunham" <rdunhamtn(at)hotmail.com> |
Subject: | Hobbs meter wiring |
I've noticed on the Rotax 912UL wiring diagrams that the "L" pin on the VR
is for a lamp which indicates charge and is usually only "on" at run-up
speed or greater.
Has anyone tried using this as a DCV source for the Hobbs meter? Seems it
would give good "flying time" readings and, or course, no falsely high "I
left the master switch on overnight" readings! Only engine on and RPM's
above warm-up times.
I was thinking run a wire to the meter with an in-line fuse, say 3 amps,
would do the trick.
Any thoughts?
Rodney in Tennessee
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: FW: Wiring details for Vans 60A |
alternator
>Hi Bob et al-
>
>I've been off the list for a while and missed your original request for
>alternator info. As it happens, I've been doing some research into this
>very topic of late, and have made some interesting discoveries. First,
>Van's input was that the exact color of the wires in the 3 wire plug
>changes now and then, and shouldn't be used as a basis for wiring the
>alternator up. They did say that the 3 spade connectors in the plug
>assembly are in a 'pi' configuration, 2 blades being parallel and one at
>right angles. The odd blade is not used, and the 2 parallel ones are tied
>together and run to the ALT switch.
>
>Second, I found a high volume overhauler who seemed very knowledgeable
>and willing to share his expertise. According to him, that top spade in
>the pi, the one at right angles, in the case of vans specific unit (Vans
>#14684, ND unit # 14824) is the 'D' terminal, 'D' as in 'dummy'. It's not
>connected to anything. The left leg of the pi is the 'I' terminal. 'I'
>stands for 'Ignition', which is what that terminal connects to. The right
>leg of the pi is 'L' for 'Light', and connects to the ALT idiot light.
>
>The most interesting thing is that the labelling of the terminals has only
>to do with the wire routing, and not much to do with their function. The
>'I' terminal is actually the voltage sense input, and in a car would be
>fed anytime the ignition was on. The 'L' terminal is the 'ON' signal
>input. It would be connected to the 'run' position of the ignition switch
>via the idiot light lamp. With the ignition switch in 'run', a +V signal
>with little or no current turns the ALT on, but won't light the
>lamp. With the ALT inop for any reason, the 'L' terminal goes to ground
>and the lamp illuminates. Curiously, this implies that a failure of the
>ALT lamp will cause the alternator to shut down, and without the idiot
>light coming on. Last, removing the +V from the 'L' terminal does shut
>the alternator down per it's spec.
>
>Hope this info is useful-
>
>
>Glen Matejcek
Yessir. Thanks!
I've located numerous references where the physical
pinouts for the ND products is shown. I've not seen
any of Van's documents yet but it occurs to me that
he is not building his connector-pigtail assemblies
from scratch but buying them. The alternator test
industry seems to have a convention for assigning
colors that is consistent with all the test adapters
I've seen advertised.
I've seen on the net where if you position a view
of the connector such that you're looking at two
vertical tabs above a horizontal tab, the tab on the
upper right will have a green wire on it and this
will be the IG or alternator control lead. The upper
left will have a red wire on it and will be the connection
for the alternator's built in fault light. The lower,
horizontal tab will be the bus sense lead and is
connected with a blue wire. See
http://www.aeroelectric.com/Reference_Docs/Alternator_Data/ND_3-wire.jpg
My sketch is upside down from the description Glen
gave us above . . . so the l-r labels are reversed.
Glen's post further suggests that Van may not get his
pigtailed connectors from a consistent source and, of
course, no source is obligated to adopt the alternator
testing community's conventions for color code.
Since the lamp drive inside the alternator pulls toward
ground on free end of a lamp tied to the bus, I was
concerned about tying the lamp (right-hand/red) terminal to
to the IG (left-hand/green) terminal. This might cause
the IC to pull down hard on a short circuit to bus
and destroy that portion of the chip that drives a
warning light unless protective measures are included
on voltage regulator chip. Turns out that the required
measures do exist and while it would be BETTER to put
a lamp (or 100 ohm resistor) in series with the
lamp terminal, it's not unduly hard on the chip to
make a hard connection.
The warning light is redundant to active notification
of low voltage generally recommended for all aircraft
power systems so the lamp wire from the alternator can
be tied to the IGN lead with or without the series
resistor.
If ALL ND alternators have a bus sense lead (and
from what I've been able to deduce so far, they
do) this opens some VERY interesting opportunities for
crafting a positive ON/OFF control scheme that meets
the design goals I've suggested for integration of
the internally regulated alternator into aircraft.
I'll continue to pursue this line of thinking and
share my findings and deductions with the group at
some time in the not too distant future.
Bob . . .
________________________________________________________________________________
From: | "Ed Anderson" <eanderson(at)carolina.rr.com> |
Subject: | Re: Belt replacement (was Alternator Speed) |
Strongly support Bob's suggestion of using Gates Belts for alternator.
Prevention is always better than the cure..
I used a less expensive brand of belt once and after only 20 hours, a keen
eyed Nephew fortunately notice that "cogs" were missing from the belt.
Replaced the belts immediately with Gates and after 160 hours they still
appear brand new.
Ed Anderson
Rv-6A N494BW Rotary Powered
Matthews, NC
eanderson(at)carolina.rr.com
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckollsr(at)cox.net>
Subject: Re: AeroElectric-List: Belt replacement (was Alternator Speed)
>
>
>
>>
>>
>> Would you trade off better alternator performance at low engine
>> speeds for longer service life on a belt?
>>
>> >>>>
>>
>>Which brings up something I don't recall seeing discussed here or on
>>RV-list:
>> What is typical failure mode for belt and what is potential for/scope of
>>"collateral damage" in event of failure? How is belt condition best
>>determined
>>and what is best practice for determining replacement interval?
>>
>>Thanks- Mark Phillips
>
> Belts will show distinct signs of distress long before catastrophic
> failure. Cracks, polished sides of the "V", and cords exposed
> or hanging out are all reasons to consider replacement. Of course,
> you have to pull the prop to replace a belt. I've seen airplanes
> at airshows where a "spare" belt was installed over the prop
> shaft and secured behind the ring gear pulley. The idea was
> that a broken belt could be replaced by simply loosening the
> alternator belt tightening brackets and slipping the new one
> into place without removing the prop. I asked a few owners
> of such aircraft if they'd ever taken advantage of this feature
> or knew anyone else who had . . . none answered in the affirmative.
>
> V-belts on aircraft are generally very lightly loaded. Alternators
> draw less than 1 h.p. in cruise. Exposure to the elements while
> parked probably represents a bulk of the stresses on a belt that
> would reduce time in service. Poor tensioning practice can also
> reduce life . . .
>
> If a looksee and feel before flight passes muster on a quality
> belt, it's going to still be there doing its job when you land.
>
> Bob . . .
>
> Buy good quality belts (Gates) and replace at first signs of
> distress (which will be years of time and hundreds of hours
> of flight) or at any time you happen to pull the prop, put a new
> belt on. Like batteries, well monitored and maintained belts
> are VERY low on your list of concerns for finding yourself
> "up there" and wishing you were "down here".
>
> Bob . . .
>
>
>
________________________________________________________________________________
From: | "bob noffs" <icubob(at)newnorth.net> |
hi bob,
thanks for the advice on wiring my turn coor. now that i know i can do it with
enough clearance forward of my panel i can move on to solve other mysteries.
bob noffs
dakota hawk builder
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: degaussing (demagnetizing) my roll |
bar
>
>
>This is probably not permanent magnetism of the rollbar but just the
>fact that a potentially magnetic material (steel in this case) distorts
>the earth's magnetic field in the vicinity of the rollbar and thereby
>causes the compass needle to point in a direction not entirely aligned
>with the earth's normal magnetic field alignment. This is why any piece
>of avionics that uses a magnetometer (electronic compass) cautions you
>to place it far away from any steel.
>
>Lines of magnetic of force tend to (will) take the easiest path to
>connect from the north pole to the south pole. Any potentially magnetic
>material (whether it is magnetized or not) will provide a much easier
>path than air. When this happens, the compass still aligns with the
>resultant lines of force - but the lines of force no longer align with
>what is expected.
>
>If the roll bar is actually magnetized then the effect is typically much
>more pronounced. A magnetized rollbar likely has a much greater
>magnetic field than the earth.
>
>The only way I know of to determine which of the two above cases is
>causing the compass to move, aside from using gigantic Helmholtz coils,
>is to rotate the rollbar (or entire plane) around the compass rose,
>while holding the compass in the same position relative to the rollbar
>and observe the compass needle. If the rollbar is magnetized the needle
>will likely continue to point to roughly the same direction relative to
>the rollbar. If it is just the distortion of the earth's magnetic
>field, then the compass will rotate as the rollbar is rotated.
>
>None of this is particularly pertinent except one should understand
>that, just because a compass needle moves in the vicinity of a piece of
>steel, the steel is not necessarily magnetized - so demagnetizing it in
>that case would have no effect.
>
>My $0.02...
>
>Dick Tasker
Well stated sir. Thanks!
Bob . . .
________________________________________________________________________________
From: | "Terry Watson" <terry(at)tcwatson.com> |
Subject: | Belt replacement (was Alternator Speed) |
I recall seeing v-belts that were made up of removable links. The advantage
was claimed to be that you could adjust the length to fit. It would seem to
be an excellent spare that you could install to get home without pulling the
prop, IF they work. Does anyone have any experience of knowledge of them?
Terry
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Ed
Anderson
Subject: Re: AeroElectric-List: Belt replacement (was Alternator Speed)
Strongly support Bob's suggestion of using Gates Belts for alternator.
Prevention is always better than the cure..
I used a less expensive brand of belt once and after only 20 hours, a keen
eyed Nephew fortunately notice that "cogs" were missing from the belt.
Replaced the belts immediately with Gates and after 160 hours they still
appear brand new.
Ed Anderson
Rv-6A N494BW Rotary Powered
Matthews, NC
eanderson(at)carolina.rr.com
________________________________________________________________________________
From: | Werner Schneider <glastar(at)gmx.net> |
Subject: | Re: Solid State Gyros |
Hello Deke,
I had an RC-Allen Gyro in my Glastar until the Tacho showed around 45
hrs, I have now a Dynon D-10A with external magnetic pickup (the Glastar
has a steel cage).
The RC-Allen was slower and heavier, I have now over 100 hrs on my
Dynon, love the way it handles and display as well as having the
checklists always ready the horizon shows very accurate (even in mild
acro) and appart from some overheating at the begining (directly under
the glare shield) which it did prompt immediately I had so far no problems.
Werner
BTW just sold the RC-Allen which paid nearly for the Dynon, I would not
like to go back.
Fox5flyer wrote:
>
>I'm in the market for an electric Artificial Horizon gyro. I'm not planning on
any hard IMC. I just want something to help with pitch and roll when I get
into a short term situation, like haze over the water.
>The options I've found are the RC Allen (very expensive) and Falcon (about half).
Both are mechanical and provide no other information.
>The other option is to go solid state with lots of information. There are the
Trutrack and Dynon units to name a couple. I don't have any experience with
the new solid state units at all. I'd like to keep my expenses under or around
$2500. Here are my questions.
>
>1. Does anybody have any experience with the Falcon electric AH? Reliability?
>
>2. Does anybody have any experience with any of the solid state units? Positive
or negative.
>
>3. Do the solid state units provide the same accuracy as the mechanical units?
>
>4. Are the solid state units reliable?
>
>5. How do the solid state units work, pitch-roll-heading?
>
>6. Other than those that I mentioned above, are there any others out there that
are worth persuing.
>
>Thanks for any info offered.
>
>Deke
>Mikado MI
>
>
>
>
________________________________________________________________________________
From: | Werner Schneider <glastar(at)gmx.net> |
Subject: | Re: Hobbs meter wiring |
I'm using a pressure switch adjusted a tad over the Vs0 hooked into the
pitot line to get flying time.
br
Werner
Rodney Dunham wrote:
>
>I've noticed on the Rotax 912UL wiring diagrams that the "L" pin on the VR
>is for a lamp which indicates charge and is usually only "on" at run-up
>speed or greater.
>
>Has anyone tried using this as a DCV source for the Hobbs meter? Seems it
>would give good "flying time" readings and, or course, no falsely high "I
>left the master switch on overnight" readings! Only engine on and RPM's
>above warm-up times.
>
>I was thinking run a wire to the meter with an in-line fuse, say 3 amps,
>would do the trick.
>
>Any thoughts?
>
>Rodney in Tennessee
>
>
>
>
________________________________________________________________________________
From: | Mickey Coggins <mick-matronics(at)rv8.ch> |
Subject: | Re: FW: Wiring details for Vans 60A alternator |
> If ALL ND alternators have a bus sense lead (and
> from what I've been able to deduce so far, they
> do) this opens some VERY interesting opportunities for
> crafting a positive ON/OFF control scheme that meets
> the design goals I've suggested for integration of
> the internally regulated alternator into aircraft.
> I'll continue to pursue this line of thinking and
> share my findings and deductions with the group at
> some time in the not too distant future.
My ND alternator does not have an independent bus sense
lead, but perhaps it is sensing this via the IGN terminal?
http://www.rv8.ch/article.php?story=2004112513263691
--
Mickey Coggins
http://www.rv8.ch/
#82007 finishing
________________________________________________________________________________
From: | "Jim Jewell" <jjewell(at)telus.net> |
Subject: | Re: Belt replacement (was Alternator Speed) |
Hi Terry,
I don't remember the brand name of the belt you might be thinking of:
The camshaft grinding company that provided a space for us to maintain
various race cars used a leather multi-link type belt on their cam grinding
lathes.
They use this type of belt because the multiple leather links absorbed
vibrations transmitted to and from the drive motor during the finishing
stage of grinding cams. This allowed the operator to reduce if not eliminate
the almost microscopic ripples on the finished cam lobe surfaces that would
be present if a standard vee belt was used.
I would be wary of using this type of belt as the RPM limit and loading
might be beyond the design capability of these belts. Checking for
application suitability with the manufacturer before use would be a must!
There might be a non leather variety out there.
Though unlikely, each link has a metal clip that might cause trouble should
a failure occur while airborne. Standard vee belts failure mode is most
often benign. The belt breaks and falls away.
However. if the broken belt somehow comes to rest on the exhaust it could
make for some precision upholstery button removal! {[8-o
Keep the battery up.
Jim in Kelowna
----- Original Message -----
From: "Terry Watson" <terry(at)tcwatson.com>
Subject: RE: AeroElectric-List: Belt replacement (was Alternator Speed)
>
>
> I recall seeing v-belts that were made up of removable links. The
> advantage
> was claimed to be that you could adjust the length to fit. It would seem
> to
> be an excellent spare that you could install to get home without pulling
> the
> prop, IF they work. Does anyone have any experience of knowledge of them?
>
> Terry
>
>
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Ed
> Anderson
> To: aeroelectric-list(at)matronics.com
> Subject: Re: AeroElectric-List: Belt replacement (was Alternator Speed)
>
>
>
> Strongly support Bob's suggestion of using Gates Belts for alternator.
> Prevention is always better than the cure..
>
> I used a less expensive brand of belt once and after only 20 hours, a
> keen
> eyed Nephew fortunately notice that "cogs" were missing from the belt.
> Replaced the belts immediately with Gates and after 160 hours they still
> appear brand new.
>
> Ed Anderson
> Rv-6A N494BW Rotary Powered
> Matthews, NC
> eanderson(at)carolina.rr.com
>
>
>
________________________________________________________________________________
From: | "Jim Jewell" <jjewell(at)telus.net> |
Subject: | Re: Belt replacement (was Alternator Speed) |
Hi again Terry,
I found this link to a site that seems to have some good information re
multilink type vee belts.
http://www.fennerindustrial.com/products/powertwist_ind.html
I hope this helps,
Jim in Kelowna
________________________________________________________________________________
Subject: | Re: Belt replacement (was Alternator Speed) |
From: | James H Nelson <rv9jim(at)juno.com> |
Terry,
I sell that type of belting. Its a urethane based product so it
fairly tough and chemically resistant. Its drawback is the flexability
in the length mode. Its a great backup item. You just need to know that
you will need to install it in the shortest configuration because it
streaches due to the links taking up the slack as you tension the belt.
Not a biggie, just a heads up. I had not thought about it myself but now
you have raised the issue, I will put several feet (determined after I
get my engine installed) in my maintenance cubby under the floor in the
back. By the way, it only takes a pair of pliers to adjust the length.
The belt does not have any metal in it. It will carry the same loads as
a standard belt. Its rather expensive in comparison to a regular v-belt.
But, it beats removing the prop some where (not at home).
Jim Nelson
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: FW: Wiring details for Vans 60A |
alternator
>
>
> > If ALL ND alternators have a bus sense lead (and
> > from what I've been able to deduce so far, they
> > do) this opens some VERY interesting opportunities for
> > crafting a positive ON/OFF control scheme that meets
> > the design goals I've suggested for integration of
> > the internally regulated alternator into aircraft.
> > I'll continue to pursue this line of thinking and
> > share my findings and deductions with the group at
> > some time in the not too distant future.
>
>
>My ND alternator does not have an independent bus sense
>lead, but perhaps it is sensing this via the IGN terminal?
>
> http://www.rv8.ch/article.php?story=2004112513263691
Aha! A two-lead version. Can't speak directly to the
control philosophy in ND's regulator chip but similar
devices offered to the same market will watch the bus
sense lead and if there is no connection, the chip reverts
to b-lead sense mode. See:
http://www.aeroelectric.com/Reference_Docs/Alternator_Data/MC33099_Schematic.pdf
This schematic is an exemplar regulator chip offered
by Freestyle (Motorola). This is a pretty "busy" chip!
In 1975, the functional equivalents to this device had about
8 transistors, a couple of precision zeners and a relay.
In the upper left corner of the schematic we see the automatic
changeover from local to remote sensing of regulation voltage
depending on whether or not the remote sense pin is hooked to
anything interesting. In the lower right corner, we see the
current and temperature limited lamp driver circuit which
allows one to make a hard connection between LAMP and IGN
terminals without serious risk to the chip.
A further feature of note is what's called an OVER VOLTAGE
DETECTOR in the middle. No doubt this section of the chip
has some functionality for the implied purpose. However,
nobody I know of in the aviation world would consider an
embedded OV protection circuit to have adequate separation
between CONTROL and PROTECTION. While a citation for
"Built in ov protection" looks good on the marketing hype
for any alternator that uses this chip, it's a huge
stretch to assume that all failure modes capable of
precipitating an OV condition will be sufficiently isolated
from the OV protection system to pass muster for a certified
power generation system for aircraft.
It's interesting to note that OV protection of ANY kind
is included on the chip. If the chip manufacturer held
their product to the same levels of infallibility as
those who preach the gospel of running internally
regulated alternators barefooted, why would they find
it useful to include ANY form of OV protection in their
product (in spite of its minimal levels of protection)?
This little study of schematics and/or block diagrams
is crucial to a learned critical design review and
failure mode effects analysis. Not having such
data for the ND regulators is the primary reason I've
been reluctant to endorse these products for indiscriminate
use on aircraft. The product may be just fine but without
such data for analysis, I can't encourage their use
from a position of understanding.
In response to the question about remote bus sensing,
it's really easy to identify the sensing method of
a particular alternator/regulator combination. Add
a temporary diode in series with the wire that
carries bus voltage toward the alternator system.
If that wire is truly a bus-sense connection, bus voltage
will jump up about 0.6v while the diode is in place and
go back down when it's removed.
Bob . . .
________________________________________________________________________________
Subject: | FW: Wiring details for Vans 60A alternator |
From: | "Hinde, Frank George (Corvallis)" <frank.hinde(at)hp.com> |
Hmmm...and similarly...If the volt sensing lead got disconnected the
Alternator would sense "zero volts" and presumably go to max output?
Maybe then, this is a good reason NOT to have an alt with a separate
sensing lead??
Frank
If that wire is truly a bus-sense connection, bus voltage
will jump up about 0.6v while the diode is in place and
go back down when it's removed.
Bob . . .
________________________________________________________________________________
Subject: | FW: Wiring details for Vans 60A alternator |
From: | "Matt Prather" <mprather(at)spro.net> |
Uh... Mmm.. Actually, it looks like there's circuitry in there to detect
that condition and fail over to running with the internal reference from
the B-lead. Check it out... The Vrem is fed to both an input buffer and
a comparator circuit with (presumably) a diode pulled up to 0.6V. If the
Vrs (tapped from the voltage divider driven by Vrem) drops below 0.6, the
comparator will flip states, causing the input source select to change
from remote sense to local.. At least that's the way it looks to me.
Regards,
Matt-
> (Corvallis)"
>
> Hmmm...and similarly...If the volt sensing lead got disconnected the
> Alternator would sense "zero volts" and presumably go to max output?
>
> Maybe then, this is a good reason NOT to have an alt with a separate
> sensing lead??
>
> Frank
>
> If that wire is truly a bus-sense connection, bus voltage
> will jump up about 0.6v while the diode is in place and
> go back down when it's removed.
>
> Bob . . .
>
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | FW: Wiring details for Vans 60A |
alternator
>
>Uh... Mmm.. Actually, it looks like there's circuitry in there to detect
>that condition and fail over to running with the internal reference from
>the B-lead. Check it out... The Vrem is fed to both an input buffer and
>a comparator circuit with (presumably) a diode pulled up to 0.6V. If the
>Vrs (tapped from the voltage divider driven by Vrem) drops below 0.6, the
>comparator will flip states, causing the input source select to change
>from remote sense to local.. At least that's the way it looks to me.
That's correct . . . and the feature I was attempting to point out.
If you hook up the remote sense, it performs as expected. If you don't
hook it up, the alternator defaults to v-sense internally at the b-lead.
The concept and value of remote sensing via a zero current conductor is
not well understood. I'm not surprised that few if any folks giving
advice suggest
using it. Then, there's the 2-wire alternators that omit this
feature entirely. The "universal" installation calls for allowing
a 3-lead machine to default to b-lead sensing. One installation schematic
fits all.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | FW: Wiring details for Vans 60A |
alternator
>
>
>Hmmm...and similarly...If the volt sensing lead got disconnected the
>Alternator would sense "zero volts" and presumably go to max output?
>
>Maybe then, this is a good reason NOT to have an alt with a separate
>sensing lead??
Every regulator I've designed defaults to a secondary if
less accurate sense path if the primary sense path is lost.
Alternatively, the system is designed for passive shutdown
if either (+) or (-) sense leads become disconnected. Such
is the case with the Motorola chip as well.
Bob . . .
________________________________________________________________________________
From: | D Wysong <hdwysong(at)gmail.com> |
Subject: | Re: Hobbs meter wiring |
Rodney -
How much current does your Hobbs draw? The 914F manual that I have says
that the Ducati "L" (lamp) line is good for a 3W/12V bulb. Seems like a
neat idea if that's enough juice to power the Hobbs.
BTW - thanks for the heads up on the lamp logic! I had assumed that the
operation of the "charge-indicating lamp" would be just the opposite...
"off" during normal operation and "on" if the system was not charging
(like the red ALT lamp in a ratty old C-150).
D
Rodney Dunham wrote:
>
> I've noticed on the Rotax 912UL wiring diagrams that the "L" pin on the VR
> is for a lamp which indicates charge and is usually only "on" at run-up
> speed or greater.
>
> Has anyone tried using this as a DCV source for the Hobbs meter? Seems it
> would give good "flying time" readings and, or course, no falsely high "I
> left the master switch on overnight" readings! Only engine on and RPM's
> above warm-up times.
>
> I was thinking run a wire to the meter with an in-line fuse, say 3 amps,
> would do the trick.
>
> Any thoughts?
>
> Rodney in Tennessee
>
>
>
>
>
>
>
________________________________________________________________________________
From: | "Jim Baker" <jlbaker(at)telepath.com> |
Subject: | Re: Hobbs meter wiring |
> BTW - thanks for the heads up on the lamp logic! I had assumed
that
> the operation of the "charge-indicating lamp" would be just the
> opposite... "off" during normal operation and "on" if the system was
> not charging (like the red ALT lamp in a ratty old C-150).
Of course you could always wire in a normally open relay that closes
on loss of power to create the first indicator scenario. My Bellanca
behaves in that manner.....
Jim Baker
580.788.2779
'71 SV, 492TC
Elmore City, OK
________________________________________________________________________________
Subject: | Re: Hobbs meter wiring |
From: | "Matt Prather" <mprather(at)spro.net> |
The LCD display Hobbs hour meter draws 0.8mA. Wow, though I guess it
really isn't any different than a digital watch which runs from a very
small battery.
http://content.honeywell.com/sensing/hss/hobbsparts/products/lcdHourMeters.asp
I couldn't find an "I" value for the mechanical meters, but 3 watts should
be plenty - roughly 250mA.
Regards,
Matt-
>
> Rodney -
>
> How much current does your Hobbs draw? The 914F manual that I have says
> that the Ducati "L" (lamp) line is good for a 3W/12V bulb. Seems like
> a neat idea if that's enough juice to power the Hobbs.
>
> BTW - thanks for the heads up on the lamp logic! I had assumed that the
> operation of the "charge-indicating lamp" would be just the opposite...
> "off" during normal operation and "on" if the system was not charging
> (like the red ALT lamp in a ratty old C-150).
>
> D
>
>
> Rodney Dunham wrote:
>>
>>
>> I've noticed on the Rotax 912UL wiring diagrams that the "L" pin on
>> the VR is for a lamp which indicates charge and is usually only "on"
>> at run-up speed or greater.
>>
>> Has anyone tried using this as a DCV source for the Hobbs meter? Seems
>> it would give good "flying time" readings and, or course, no falsely
>> high "I left the master switch on overnight" readings! Only engine on
>> and RPM's above warm-up times.
>>
>> I was thinking run a wire to the meter with an in-line fuse, say 3
>> amps, would do the trick.
>>
>> Any thoughts?
>>
>> Rodney in Tennessee
>>
>>
>>
>>
>>
>>
>>
>
>
________________________________________________________________________________
Subject: | Not quite electrical |
From: | "Hinde, Frank George (Corvallis)" <frank.hinde(at)hp.com> |
Without thinking too hard I made provision for a vertical card compass
(2 1/4") about an inch away from my audio panel and radio stack in an
RV7. It is also about an inch above the Pictorial Pilot (auto pilot).
I was about to can the idea and install a VSI in that hole and mount a
whiskey compass on top of the panel...But being a tip up canopy I'm not
sure how resilient the compass would be to this kind of abuse.
So I thought I would ask....Is the Vert card compass completely
unworkable in this location?
Thanks
Frank
________________________________________________________________________________
From: | "LarryRobertHelming" <lhelming(at)sigecom.net> |
Subject: | Re: Not quite electrical |
That is where I mounted mine with the flexible base mount on top of the
glare shield. It is still working after 63 hours. I figure in a plane
doing aerobatics, it would be going through the tilt up and down anyway. I
had originally planned to mount it in the panel but changed after reading
the warnings and concerns of others due to magnetic and radio frequency
interference. I would like it better in the panel from a sight and
appearance stand point. However, I have more room in my panel for something
else if I want it later. From my setup the compass is only a backup
instrument in case I lost all my electronics AND hand helds with GPS
capability. What are the odds of that??
Indiana Larry, RV7 Tip Up SunSeeker
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
" Happiness: like a butterfly, when pursued,
is always beyond our grasp, but which,
if one sits quietly, may light upon you."
Nathaniel Hawthorne
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
----- Original Message -----
From: "Hinde, Frank George (Corvallis)" <frank.hinde(at)hp.com>
Subject: AeroElectric-List: Not quite electrical
>
>
> Without thinking too hard I made provision for a vertical card compass
> (2 1/4") about an inch away from my audio panel and radio stack in an
> RV7. It is also about an inch above the Pictorial Pilot (auto pilot).
>
> I was about to can the idea and install a VSI in that hole and mount a
> whiskey compass on top of the panel...But being a tip up canopy I'm not
> sure how resilient the compass would be to this kind of abuse.
>
> So I thought I would ask....Is the Vert card compass completely
> unworkable in this location?
>
> Thanks
>
> Frank
>
>
>
________________________________________________________________________________
From: | "bob noffs" <icubob(at)newnorth.net> |
hi all,
i have the washers for toggle switches that have the small tab which locks into
a 1/8'' hole drilled in the ins. panel. before i drill all these 1/8'' holes
in a so far perfect panel does anyone have any opinions or experience with this
system? can the holes be hidden with the control labels? etc. seems like a
good idea to keep all the switches from turning.
thanks for any input.
bob noffs
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
>
>hi all,
> i have the washers for toggle switches that have the small tab which
> locks into a 1/8'' hole drilled in the ins. panel. before i drill all
> these 1/8'' holes in a so far perfect panel does anyone have any opinions
> or experience with this system? can the holes be hidden with the control
> labels? etc. seems like a good idea to keep all the switches from
> turning.
> thanks for any input.
> bob noffs
I recommend them. You can put anti rotation washers on the back
side of the panel, trim the tabs to be flush with the front
surface and the cover them with an engraved overlay that
labels the switches.
Bob . . .
________________________________________________________________________________
From: | "Jim Jewell" <jjewell(at)telus.net> |
Hi Bob,
options:
Drill holes for positioning tabs install the tabbed washers out front (in
sight) and live with the look.
Drill very shallow holes from the rear side of the switch panel. If the
switch panel seems too thin for this add a doubler with the holes predrilled
in it. Put the tabs onto the switches tab out then install the switches
without the tabs or holes visible from the front. Flat washers without tabs
will keep the scratches to a minimum during install
keep building,
Jim in Kelowna
----- Original Message -----
From: "bob noffs" <icubob(at)newnorth.net>
Subject: AeroElectric-List:
>
> hi all,
> i have the washers for toggle switches that have the small tab which locks
> into a 1/8'' hole drilled in the ins. panel. before i drill all these
> 1/8'' holes in a so far perfect panel does anyone have any opinions or
> experience with this system? can the holes be hidden with the control
> labels? etc. seems like a good idea to keep all the switches from turning.
> thanks for any input.
> bob noffs
>
>
>
________________________________________________________________________________
From: | "Jim Jewell" <jjewell(at)telus.net> |
Hi Bob,
options:
Drill holes for positioning tabs install the tabbed washers out front (in
sight) and live with the look.
Drill very shallow holes from the rear side of the switch panel. If the
switch panel seems too thin for this add a doubler with the holes predrilled
in it. Put the tabs onto the switches tab out then install the switches
without the tabs or holes visible from the front. Flat washers without tabs
will keep the scratches to a minimum during install
keep building,
Jim in Kelowna
----- Original Message -----
From: "bob noffs" <icubob(at)newnorth.net>
Subject: AeroElectric-List:
>
> hi all,
> i have the washers for toggle switches that have the small tab which locks
> into a 1/8'' hole drilled in the ins. panel. before i drill all these
> 1/8'' holes in a so far perfect panel does anyone have any opinions or
> experience with this system? can the holes be hidden with the control
> labels? etc. seems like a good idea to keep all the switches from turning.
> thanks for any input.
> bob noffs
>
>
>
________________________________________________________________________________
From: | <robert.mccallum2(at)sympatico.ca> |
Subject: | Re: ectric-List: |
Bob
One method of utilizing these washers which does not impact the panel itself, is
to add a strip of aluminium behind the panel where the switches are mounted
into which you drill these tab holes and which you drill for the switch bushings.
If your switches are in groups you can make one of these plates for each
group of switches. They are retained by the switches themselves and give the washers
the required antirotation grip without defacing the panel. As long as your
panel plus the backup strip thickness total less than the grip length of your
switches this will work. The added strip just needs to be as thick as the
depth of the washer tab.
Bob McC
>
> From: "bob noffs" <icubob(at)newnorth.net>
> Date: 2005/09/27 Tue PM 11:06:16 EDT> To: "aeroelectric list"
> Subject: AeroElectric-List:
>
>
________________________________________________________________________________
From: | "Richard E. Tasker" <retasker(at)optonline.net> |
Subject: | Re: ectric-List: |
Unless your panel is really thin, you can drill a hole partially into
the rear of the panel and use these that way. No rotation, no visibility!
You do have to be careful, but you might be able to use a the same thing
you use to limit the depth of the countersinks or if you have a drill
press with stops.
Dick Tasker
bob noffs wrote:
>
>hi all,
> i have the washers for toggle switches that have the small tab which locks into
a 1/8'' hole drilled in the ins. panel. before i drill all these 1/8'' holes
in a so far perfect panel does anyone have any opinions or experience with this
system? can the holes be hidden with the control labels? etc. seems like a
good idea to keep all the switches from turning.
> thanks for any input.
> bob noffs
>
----
Please Note:
No trees were destroyed in the sending of this message. We do concede, however,
that a significant number of electrons may have been temporarily inconvenienced.
----
________________________________________________________________________________
From: | HCRV6(at)comcast.net |
I drilled a very small hole, #40 I think, and then used a needle file to elongate
the hole just enough to fit the tang on the washer. The holes are competely
filled by the tang and don't show at all.
--
Harry Crosby
RV-6 N16CX, 133 hours
I drilled a very small hole, #40 I think, and then used a needle file to elongate
the hole just enough to fit the tang on the washer. The holes are competely
filled by the tang and don't show at all.
--
Harry Crosby
RV-6 N16CX, 133 hours
________________________________________________________________________________
Put the holes and washers on the back side of the panel, don't drill
thru-holes.
Sam Chambers
Long-EZ N775AM
Glasgow, KY
----- Original Message -----
From: "bob noffs" <icubob(at)newnorth.net>
Subject: AeroElectric-List:
>
> hi all,
> i have the washers for toggle switches that have the small tab which locks
> into a 1/8'' hole drilled in the ins. panel. before i drill all these
> 1/8'' holes in a so far perfect panel does anyone have any opinions or
> experience with this system? can the holes be hidden with the control
> labels? etc. seems like a good idea to keep all the switches from turning.
> thanks for any input.
> bob noffs
>
>
>
________________________________________________________________________________
Oh, yeah, your panel may be too thin for my previous posting. In that case,
follow Bob's advice (always a good idea).
Sam Chambers
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckollsr(at)cox.net>
Subject: Re: AeroElectric-List:
>
>
>
>>
>>hi all,
>> i have the washers for toggle switches that have the small tab which
>> locks into a 1/8'' hole drilled in the ins. panel. before i drill all
>> these 1/8'' holes in a so far perfect panel does anyone have any opinions
>> or experience with this system? can the holes be hidden with the control
>> labels? etc. seems like a good idea to keep all the switches from
>> turning.
>> thanks for any input.
>> bob noffs
>
> I recommend them. You can put anti rotation washers on the back
> side of the panel, trim the tabs to be flush with the front
> surface and the cover them with an engraved overlay that
> labels the switches.
>
> Bob . . .
>
>
>
________________________________________________________________________________
From: | "Rodney Dunham" <rdunhamtn(at)hotmail.com> |
Bob
The only thing I would add to the others is this. Lay out the small 1/8"
holes at the same time you lay out the switch holes. In other words, draw
out the whole switch plan, including the tab holes, before drilling the
first hole. I drilled the big holes without thinking ahead and it is very
difficult to get the small holes lined up just right afterwords. You can get
the exact dimensions in the Connection. I think it's in the chapter on
switches. Imagine that :o)
One other tip: If you use the ON-ON, I think it's switch 3-3, you can drill
the tab hole below the switch hole and hide it without losing the up-is-on
architecture on the panel. You just have to remember that the pin numbers
are now upside down but that's easy, the tab reminds you.
Rodney in Tennessee
>From: "bob noffs" <icubob(at)newnorth.net>
>Reply-To: aeroelectric-list(at)matronics.com
>To: "aeroelectric list"
>Subject: AeroElectric-List: Date: Tue, 27 Sep 2005 22:06:16 -0500
>
>
>hi all,
> i have the washers for toggle switches that have the small tab which
>locks into a 1/8'' hole drilled in the ins. panel. before i drill all these
>1/8'' holes in a so far perfect panel does anyone have any opinions or
>experience with this system? can the holes be hidden with the control
>labels? etc. seems like a good idea to keep all the switches from turning.
> thanks for any input.
> bob noffs
>
>
________________________________________________________________________________
From: | Charlie Kuss <chaztuna(at)adelphia.net> |
Subject: | Re: Hobbs meter wiring |
Werner,
Could you give us the Manufacturer and model number of the switch you are
using?
Charlie Kuss
>
>I'm using a pressure switch adjusted a tad over the Vs0 hooked into the
>pitot line to get flying time.
>
>br
>
>Werner
>
>Rodney Dunham wrote:
>
>
> >
> >I've noticed on the Rotax 912UL wiring diagrams that the "L" pin on the VR
> >is for a lamp which indicates charge and is usually only "on" at run-up
> >speed or greater.
> >
> >Has anyone tried using this as a DCV source for the Hobbs meter? Seems it
> >would give good "flying time" readings and, or course, no falsely high "I
> >left the master switch on overnight" readings! Only engine on and RPM's
> >above warm-up times.
> >
> >I was thinking run a wire to the meter with an in-line fuse, say 3 amps,
> >would do the trick.
> >
> >Any thoughts?
> >
> >Rodney in Tennessee
> >
> >
> >
> >
>
>
________________________________________________________________________________
From: | "John Schroeder" <jschroeder(at)perigee.net> |
Bob -
Drill the holes for the tabs on the back of the panel and don't drill all
the way through - if you can help it.
John Schroeder
>
>
> hi all,
> i have the washers for toggle switches that have the small tab which
> locks into a 1/8'' hole drilled in the ins. panel. before i drill all
> these 1/8'' holes
________________________________________________________________________________
From: | "bob rundle" <bobrundle2(at)hotmail.com> |
Subject: | GMA340 and marker beacon |
I have a GMA340 audio panel with marker beacon indicator lights.
I also have a marker beacon antenna which is just a simple copper tape.
How do I hook up the marker antenna to the GMA340? I see no antenna
connection on the back of the unit.
THKX
BOB
http://search.msn.click-url.com/go/onm00200636ave/direct/01/
________________________________________________________________________________
Subject: | GMA340 and marker beacon |
From: | "Stewart, Michael (ISS Atlanta)" <mstewart(at)iss.net> |
Referring to the installation manual, it is wired to pins 1&2 on
connector J1.
Page 15 of the manual. You do have one right? Well if you don't then you
can d/l it here:
http://www.garmin.com/manuals/GMA340AudioPanel_InstallationManual.pdf
You can figure out how to d/l virtually any Garmin manual from rv list
message number 124785.
Or from here:
http://www2.mstewart.net:8080/Downloads/howtogetagarminmanual.htm
Enjoy,
Mike
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of bob
rundle
Subject: AeroElectric-List: GMA340 and marker beacon
I have a GMA340 audio panel with marker beacon indicator lights.
I also have a marker beacon antenna which is just a simple copper tape.
How do I hook up the marker antenna to the GMA340? I see no antenna
connection on the back of the unit.
THKX
BOB
http://search.msn.click-url.com/go/onm00200636ave/direct/01/
________________________________________________________________________________
From: | "Glen Matejcek" <aerobubba(at)earthlink.net> |
Subject: | Wiring details for Vans 60A alternator |
Hi Mickey-
>My ND alternator does not have an independent bus sense
>lead, but perhaps it is sensing this via the IGN terminal?
>
>
>Mickey Coggins
Try the Tech Dept of Worldwide Auto, 300 W. Brooker, Winchester, VA 22603,
540-667-9100. I gave them my part number, and they gave me all the specs I
wanted. Very helpful folks.
Glen Matejcek
aerobubba(at)earthlink.net
________________________________________________________________________________
From: | "Hinde, Frank George (Corvallis)" <frank.hinde(at)hp.com> |
I forgot the washers and use a dab of shoe glue or silicone sealant on
the back of the panel to glue the switch in place...it won't rotate
anywhere with that and it saves messing with holes and stuff and not
hard to get off if you have to replace the switch.
Frank
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
HCRV6(at)comcast.net
Subject: Re: AeroElectric-List:
I drilled a very small hole, #40 I think, and then used a needle file to
elongate the hole just enough to fit the tang on the washer. The holes
are competely filled by the tang and don't show at all.
--
Harry Crosby
RV-6 N16CX, 133 hours
I drilled a very small hole, #40 I think, and then used a needle file to
elongate the hole just enough to fit the tang on the washer. The holes
are competely filled by the tang and don't show at all.
--
Harry Crosby
RV-6 N16CX, 133 hours
________________________________________________________________________________
From: | Mickey Coggins <mick-matronics(at)rv8.ch> |
Subject: | ND two-lead alternator question |
Thanks for all the help getting me up to speed on
this alternator. Another quick question...
I'd like to install the "idiot light" on my two-lead
ND alternator, but I read earlier that I should either
use a lamp or a a (100 ohm?) resistance. I've got some LEDs
but I can't quite figure out if they have enough
resistance. Here are some pictures of the LEDs.
http://www.rv8.ch/article.php?story=2004112513263691
If I can't use a LED, I guess I'll just tie in the
L terminal to the IGN terminal with the 100 ohm resistance.
Thanks,
Mickey
--
Mickey Coggins
http://www.rv8.ch/
#82007 finishing
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: ND two-lead alternator question |
>
>
>Thanks for all the help getting me up to speed on
>this alternator. Another quick question...
>
>I'd like to install the "idiot light" on my two-lead
>ND alternator, but I read earlier that I should either
>use a lamp or a a (100 ohm?) resistance. I've got some LEDs
>but I can't quite figure out if they have enough
>resistance. Here are some pictures of the LEDs.
>
> http://www.rv8.ch/article.php?story=2004112513263691
>
>If I can't use a LED, I guess I'll just tie in the
>L terminal to the IGN terminal with the 100 ohm resistance.
>
>Thanks,
>Mickey
Do you have a low voltage warning light? Again, like
the so called "OV Protection" built into the regulator
chip, there are reliability issues with using the same
chip to annunciate non-operation as well as control an alternator.
A battery voltage less than 13.0 volts says it all and
this is best accomplished with a system that gets pre-flight
tested and is independent of the alternator or its regulator.
Bob . . .
________________________________________________________________________________
Subject: | Re: ND two-lead alternator question |
Hi Mickey,
Your LED says 12 V, 30 mA, so that's a 400 ohm load. I don't
know if that's close enough to 100 ohms to make the alternator happy.
To be sure, put a 120 to 150 ohm resistor in parallel with it and it
will be about right. The resistor will be dissipating about a watt, so
use at least 2 W resistor.
Bob White
Mickey Coggins wrote:
>
> Thanks for all the help getting me up to speed on
> this alternator. Another quick question...
>
> I'd like to install the "idiot light" on my two-lead
> ND alternator, but I read earlier that I should either
> use a lamp or a a (100 ohm?) resistance. I've got some LEDs
> but I can't quite figure out if they have enough
> resistance. Here are some pictures of the LEDs.
>
> http://www.rv8.ch/article.php?story=2004112513263691
>
> If I can't use a LED, I guess I'll just tie in the
> L terminal to the IGN terminal with the 100 ohm resistance.
>
> Thanks,
> Mickey
>
--
http://www.bob-white.com
N93BD - Rotary Powered BD-4 (real soon)
Prewired EC2 Cables - http://www.roblinphoto.com/shop/
________________________________________________________________________________
From: | "Fox5flyer" <morid(at)northland.lib.mi.us> |
Subject: | Solid State Gyros |
Thanks for the feedback. My airplane has been flying for 5 years and I already
have the Grand Rapids EIS system which I've been very happy with. Because of
this I don't really need an instrument like the Dynon which has a lot of information,
most of which I already have. If I were building a new panel I'd seriously
consider the Dynon or Blue Mountain unit. All I really need is the AH
gyro itself with perhaps heading/track. The most important thing is that it
fit in a 3.125 instrument hole because I don't want to have to build a new panel.
It'll fit in a hole that is already cut and plugged, waiting for me to decide
what to do.
Currently I'm considering the Trutrack ADI. http://www.trutrakflightsystems.com/ttfsinstruments.html
Does anyone out there have real time behind this instrument that is pro or con?
The thing I like most about it is that it's simple without a lot of other information
that I don't need. What I need to ensure is that it will do the job
I'm looking for, which is to get me out of trouble should that time ever arise.
Deke
Kitfox Series 5
State Gyros
> Take a serious look at their Model 4000 pictured on the
> link below, for
> the new Horizon EFIS.
> http://hometown.aol.com/enginfosys/
> Seriously good people to deal with.
Also--
I dont think I've seen mentioned the Blue Mountain
EFIS-Lite/G3. Looks similar, but includes internal GPS w.
moving map for the same $2800. Is it time for some
competitive price-reductions?? See:
http://www.bluemountainavionics.com/elitemain.php
--Richard, 601-XL, Jab3300
________________________________________________________________________________
From: | Mickey Coggins <mick-matronics(at)rv8.ch> |
Subject: | Re: Wiring details for Vans 60A alternator |
>>My ND alternator does not have an independent bus sense
>>lead, but perhaps it is sensing this via the IGN terminal?
>>
>>
>
> Try the Tech Dept of Worldwide Auto, 300 W. Brooker, Winchester, VA 22603,
> 540-667-9100. I gave them my part number, and they gave me all the specs I
> wanted. Very helpful folks.
Hi Glen,
Thanks for the pointer. I spoke to Jim in the tech department, and
he told me that I should use the L terminal to turn on and off the
alternator. Good info! I've also sent a e-mail to Denso to see if
they have any data sheets or spec sheets or any technical information
about this alternator. (Denso 100211-1680)
Jim also said that the alternator wants to see a slightly
lower voltage on the L terminal than that of the IG terminal. He
also said that a LED is fine to use as an "idiot light".
--
Mickey Coggins
http://www.rv8.ch/
#82007 finishing
________________________________________________________________________________
From: | Fiveonepw(at)aol.com |
Subject: | Re: Not quite electrical |
In a message dated 9/27/05 6:42:52 PM Central Daylight Time,
frank.hinde(at)hp.com writes:
> So I thought I would ask....Is the Vert card compass completely
> unworkable in this location?
>>>>
My PAI-700 works well in the position shown here:
http://websites.expercraft.com/n51pw/index.php?q=log_entry&log_id=5256
Click on foto for larger view...
Mark
________________________________________________________________________________
Subject: | Not quite electrical |
From: | "Hinde, Frank George (Corvallis)" <frank.hinde(at)hp.com> |
Thanks Mark....
I have much more avionics gear than you do near the hole for my compass
I have delusions of flying lots of IFR when I get my ticket...:)
What I really want to know is how much you paid for your paint job and
how many coast of paint did they apply for such a beautiful job???
Thanks
Frank
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
Fiveonepw(at)aol.com
Subject: Re: AeroElectric-List: Not quite electrical
In a message dated 9/27/05 6:42:52 PM Central Daylight Time,
frank.hinde(at)hp.com writes:
> So I thought I would ask....Is the Vert card compass completely
> unworkable in this location?
>>>>
My PAI-700 works well in the position shown here:
http://websites.expercraft.com/n51pw/index.php?q=log_entry&log_id=5256
Click on foto for larger view...
Mark
________________________________________________________________________________
From: | Phil Birkelbach <phil(at)petrasoft.net> |
Subject: | Re: Solid State Gyros |
My transition trainer had one in his RV-6. I flew in it for about 7
hours. I didn't look at it much but it did work well. All in all
TruTrak has a stellar reputation. Their autopilots have been flying for
years and I can't remember a single complaint about them. An attitude
indicator would be childs play compared to an autopilot. I think that
you'd be very happy with that instrument given the mission you describe.
I know the Dynon is overkill but it does make a good backup and does fit
in the 3.125 instrument hole. It's all a factor of $$$, but I'd never
consider an instrument in my panel that had a spinning gyro with the
options that we have. Pick one that fits and I'm sure that you'll be happy.
Godspeed,
Phil Birkelbach - Houston Texas
RV-7 N727WB - Phase I
http://www.myrv7.com
Fox5flyer wrote:
>
> Thanks for the feedback. My airplane has been flying for 5 years and I already
have the Grand Rapids EIS system which I've been very happy with. Because
of this I don't really need an instrument like the Dynon which has a lot of information,
most of which I already have. If I were building a new panel I'd seriously
consider the Dynon or Blue Mountain unit. All I really need is the AH
gyro itself with perhaps heading/track. The most important thing is that it
fit in a 3.125 instrument hole because I don't want to have to build a new panel.
It'll fit in a hole that is already cut and plugged, waiting for me to decide
what to do.
>Currently I'm considering the Trutrack ADI. http://www.trutrakflightsystems.com/ttfsinstruments.html
>Does anyone out there have real time behind this instrument that is pro or con?
The thing I like most about it is that it's simple without a lot of other information
that I don't need. What I need to ensure is that it will do the job
I'm looking for, which is to get me out of trouble should that time ever arise.
>Deke
>Kitfox Series 5
>
>
State Gyros
> > Take a serious look at their Model 4000 pictured on the
> > link below, for
> > the new Horizon EFIS.
> > http://hometown.aol.com/enginfosys/
> > Seriously good people to deal with.
>
> Also--
> I dont think I've seen mentioned the Blue Mountain
> EFIS-Lite/G3. Looks similar, but includes internal GPS w.
> moving map for the same $2800. Is it time for some
> competitive price-reductions?? See:
>
> http://www.bluemountainavionics.com/elitemain.php
>
> --Richard, 601-XL, Jab3300
>
>
>
>
>
________________________________________________________________________________
Subject: | Re: Solid State Gyros |
From: | "John Schroeder" <jschroeder(at)perigee.net> |
Deke -
Anything from TruTrak is very good. A friend here installed the Digitrak
with both roll & pitch and loves it. I have flown it and it is rock solid
is some reasonably bad turbulence. We are installing the DFC 250 in our
ES, but have not flown. The quality of everything is great. Their tech
support is excellent and they fix anything that isn't right. Excellent
company.
Hope this helps.
John Schroeder
wrote:
> Currently I'm considering the Trutrack ADI.
> http://www.trutrakflightsystems.com/ttfsinstruments.html
> Does anyone out there have real time behind this instrument that is pro
> or con?
--
________________________________________________________________________________
From: | Earl_Schroeder <Earl_Schroeder(at)juno.com> |
Subject: | Re: Solid State Gyros |
My Lancair has one that has an external GPS [mouse type] to provide
heading. That and the Alt hold [AlTrak] are the two most liked items in
the aircraft. If you have any specific questions, let me know. Earl
Fox5flyer wrote:
>Currently I'm considering the Trutrack ADI. http://www.trutrakflightsystems.com/ttfsinstruments.html
>Does anyone out there have real time behind this instrument that is pro or con?
The thing I like most about it is that it's simple without a lot of other information
that I don't need. What I need to ensure is that it will do the job
I'm looking for, which is to get me out of trouble should that time ever arise.
>
>
>
>
________________________________________________________________________________
From: | AI Nut <ainut(at)hiwaay.net> |
Subject: | Re: Solid State Gyros |
I'd like to incorporate on in my bird, too, but I don't want a
'complete' unit like the Dynon's etc. Guess I'm looking for a chip, or
MEMS unit, or what? Preferably, it will have a 0-5vdc output, or a USB
output.
Thanks.
Earl_Schroeder wrote:
>
>My Lancair has one that has an external GPS [mouse type] to provide
>heading. That and the Alt hold [AlTrak] are the two most liked items in
>the aircraft. If you have any specific questions, let me know. Earl
>
>Fox5flyer wrote:
>
>
>
>>Currently I'm considering the Trutrack ADI. http://www.trutrakflightsystems.com/ttfsinstruments.html
>>Does anyone out there have real time behind this instrument that is pro or con?
The thing I like most about it is that it's simple without a lot of other
information that I don't need. What I need to ensure is that it will do the
job I'm looking for, which is to get me out of trouble should that time ever arise.
>>
>>
>>
>>
>>
________________________________________________________________________________
From: | "Mark Cochran" <mac(at)atac.com> |
Subject: | Solid State Gyros |
Here's one very simple alternative:
http://www.pcflightsystems.com/
Mark Cochran
GAI Sportsman at 55%
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of AI Nut
Subject: Re: AeroElectric-List: Solid State Gyros
I'd like to incorporate on in my bird, too, but I don't want a
'complete' unit like the Dynon's etc. Guess I'm looking for a chip, or
MEMS unit, or what? Preferably, it will have a 0-5vdc output, or a USB
output.
Thanks.
Earl_Schroeder wrote:
>
>My Lancair has one that has an external GPS [mouse type] to provide
>heading. That and the Alt hold [AlTrak] are the two most liked items in
>the aircraft. If you have any specific questions, let me know. Earl
>
>Fox5flyer wrote:
>
>
>
>>Currently I'm considering the Trutrack ADI.
http://www.trutrakflightsystems.com/ttfsinstruments.html
>>Does anyone out there have real time behind this instrument that is pro or
con? The thing I like most about it is that it's simple without a lot of
other information that I don't need. What I need to ensure is that it will
do the job I'm looking for, which is to get me out of trouble should that
time ever arise.
>>
>>
>>
>>
>>
________________________________________________________________________________
From: | "Roger Evenson" <revenson(at)comcast.net> |
Subject: | Noise Clarification |
Bob: Reviewing cha. 16 on noise, I'm trying to understand the following apparent
contradiction:
One recommendation is to avoid the 'bad hair' look, and instead run wires bundled
close together as long as possible, with short breakouts. Yet, two of the
four listed noise propagation modes (magnetic and electrostatic) result from wires
in close parallel proximity.
Care to comment?
Roger.
________________________________________________________________________________
From: | Fiveonepw(at)aol.com |
Subject: | Re: Solid State Gyros |
Did you look at stuff by PCFlightSystems? Maybe they have something you can
use. I use their PDA based EFIS/GPS Nav stuff as my main PFD/NAV (VFR) and it
works quite nicely...
http://pcflightsystems.com/
Mark Phillips, RV-6A N51PW Columbia TN
________________________________________________________________________________
From: | "bob noffs" <icubob(at)newnorth.net> |
hi all,
the solution i liked best was strip of alum on the panel backside but my design
wont allow it. my plan is to try to drill part way thru. maybe shape the washertabs
like the end of a drill bit or after starting a holedeepen the hole with
a 1/8'' router bit.thanks for the ideas
bob noffs
________________________________________________________________________________
From: | <gmcjetpilot(at)yahoo.com> |
Subject: | Re: ND two-lead alternator question |
>Bob N wrote: Again, like the so called "OV Protection" built into the regulator
> chip, there are reliability issues with using the same
> chip to annunciate non-operation as well as control an alternator.
I agree you should have a separate Lo/Hi voltage indicator but not for the reasons
you state. You also address ND alternator reliability for which you have no
knowledge of and should focus on facts and not your opinion.
-The chance of an indication failure and alternator failure (of the kind that only
exist in your dreams Bob) at the same time is unlikely. The lamp driver and
detection is separate from the voltage regulator, even if the function is contained
in the same chip. It is possible that a rare fault will happen in the
first place and even more rare the indicator fails at the same time. The bulb
is more likely to fail, but you can check it every time you turn your electrical
system on before cranking the engine over. The idiot light will glow just like
your car.
-Second, the so called OV protection is more sophisticated than a so called crow
bar.Also being on-board the alternator is reacts quicker and more precisely
(despite what Bob says).
-Last the indicator not only indicates charge (or lack of charge) but also indicates
faults, like loss of remote sense, on those models so equipped. Unlike most
simple external "so called" voltage regulators, there are logic, control and
fault detections incorporated in the ND alternators internal VR.
The reason I use the ND indicator light is because that is the way real smart engineers
at ND designed the alternator to be wired. The reason I also have a Hi/Lo
volt indicator is my system management engine indicator instrument already
came with it. I am a belt and suspenders kind of guy. If you have a non electrical
dependent engine and panel or are VFR, you could get away with extra Hi/Lo
voltage indication. Even if your existing instrumentation does not have a
Hi/Lo indicator, a discrete module is a small, light weight device.
(PS: for the two wire ND's the IGN does provide voltage sense. In aircraft wiring
that is very compact where the alternator and battery are close, the remote
sense is not needed, but if you have it use it; it goes to the battery.)
Bob, you are talking about reliability issues, and you have no idea what you are
talking about. You said you have an engineering degree and understand failure
mode analysis and in particular those of the IC chips in ND alternators? Where
did you go to school and what degree did you get? I went to LSU for under grad
and UW for grad school.
What reliability data do you have? I will admit my info is anadotical, but it is
backed up by conversations with Nippon Denso engineers, auto industry electrical
service experts and the National Transportation Safety data base that tracks
reliability of all aspects of automobiles, including electrical charging systems
(alternators). Since there a millions ND alternators in service with no
record of recalls, consumer complaint or safety related issues, such as fires,
I would say that is pretty good statistics, not to mention the millions of ND
alternators in industrial equipment, going 24/7 for year after year with no
problem. What reliability info do you have? I know everyone gives Paul crap about
not showing data, lets see your ND alternator reliability data, please. (facts:
model, place, failure mode, indications and affect of failure)
George ATP, CFI(I)(ME), MSME, RV-4/7/B757/767
>From: "Robert L. Nickolas, III" <Nickolas(at)cox.net>
>Subject: Re: ND two-lead alternator question
>
>Do you have a low voltage warning light? Again, like
>the so called "OV Protection" built into the regulator
>chip, there are reliability issues with using the same
>chip to annunciate non-operation as well as control an alternator.
>A battery voltage less than 13.0 volts says it all and
>this is best accomplished with a system that gets pre-flight
>tested and is independent of the alternator or its regulator.
>Bob . . .
---------------------------------
Click here to donate to the Hurricane Katrina relief effort.
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: Noise Clarification |
>
>
>Bob: Reviewing cha. 16 on noise, I'm trying to understand the following
>apparent contradiction:
>One recommendation is to avoid the 'bad hair' look, and instead run wires
>bundled close together as long as possible, with short breakouts. Yet,
>two of the four listed noise propagation modes (magnetic and
>electrostatic) result from wires in close parallel proximity.
>
>Care to comment?
Not all wires are carriers of potential antagonistic stimulus,
not all wires are potential potential victims to such stimulus.
One needs to identify both potential antagonists and victims
and apply such measures only to those wires that will promote
happy coexistence in common wire bundles.
The majority of wires require no special attention. The few
systems where there is potential for detrimental cross-talk,
we use shields, twisted pairs, and take care to avoid ground
loops with carefully considered ground systems. These actions
make it possible for virtually all wiring to be neatly bundled
with minimal risk of degraded performance.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: ND two-lead alternator question |
>
>
> > (PS: for the two wire ND's the IGN does provide voltage sense. In
> > aircraft wiring that is very compact where the alternator and battery
> > are close, the remote sense is not needed, but if you have it use
> > it; it goes to the battery.)....
>
> > I will admit my info is anadotical,
> > but it is backed up by conversations with Nippon Denso engineers,
> > auto industry electrical service experts and the National
> > Transportation Safety data base that tracks reliability of all
> > aspects of automobiles, including electrical charging systems
> > (alternators).
The world is besot with experts, no-value-added bureaucrats
and purveyors of myth all of whom could be easily and accurately
replaced in this case by a schematic of the regulator chip
or the repeatable experiment as described below . . .
>George,
>
>Thanks for the information about the IG terminal providing
>voltage sense. Do you know where I can get some technical
>details on the two wire ND alternator that I have?
>
> http://www.rv8.ch/article.php?story=2004112513263691
>
>Basically I'd like to know the exact functions of the IG and L
>terminals. I've been getting conflicting information from
>various sources, and I'd love to know what the designers say
>it does. I've written to them, but so far no response.
Wire it up, run the alternator with solid wire in the
feeders to IG and L, then put a diode in series with
each wire one at a time. If insertion of the diode causes
bus voltage to rise by about 0.6 volts, then that wire
has been demonstrated to be a sense lead for the purpose
of providing more accurate control of bus voltage.
Bob . . .
________________________________________________________________________________
From: | PWilson <pwmac(at)sisna.com> |
Subject: | Re: ND two-lead alternator question |
HI George.
Do you have any knowledge about the Nissan recall to replace over
100000 alternators? I just wonder who provided the alternator that
had internal shorts and cause fires.
Regards, Paul W
=============
At 05:25 AM 9/29/2005, gmcjetpilot wrote:
>-------snip--------
>Since there a millions ND alternators in service with no record of
>recalls, consumer complaint or safety related issues, such as fires,
>I would say that is pretty good statistics, not to mention the
>millions of ND alternators in industrial equipment, going 24/7 for
>year after year with no problem. -----snip-----------
>George ATP, CFI(I)(ME), MSME, RV-4/7/B757/767
________________________________________________________________________________
From: | Jon Goguen <jon.goguen(at)umassmed.edu> |
Subject: | Re: Solid State Gyros |
I looked at the TruTrak ADI at Oshkosh, and came away very concerned
that it's a potentially dangerous device. If you look at their ads,
you'l see that they describe the pitch information provided as "gyro
enhanced vertical speed". As I understood the description of this
function from the TruTrak reps at Oshkosh, it differs from the pitch
info provided by a classical ADI in an important way: when the ship
changes attitude, you get an immediate indication of a change in pitch.
However, once a new stable attitude is established the pitch indicator
moves back to the horizon. Essentially, the device indicates something
more akin to the derivative of pitch than pitch per se. Maybe there
are some circumstances under which this is a good thing, but its not
clear to me what they might be. If you don't have a horizon outside
the ship, you cannot depend the TruTrak ADI to give an absolute pitch
indication.
Jon
Jon Goguen
jon.goguen(at)umassmed.edu
Central Massachusetts
Kitfox Series V Rotax 912S / N456JG (reserved)
Complete except for electrics and avionics
On Sep 28, 2005, at 8:59 PM, Fiveonepw(at)aol.com wrote:
>
> Did you look at stuff by PCFlightSystems? Maybe they have something
> you can
> use. I use their PDA based EFIS/GPS Nav stuff as my main PFD/NAV
> (VFR) and it
> works quite nicely...
>
> http://pcflightsystems.com/
>
> Mark Phillips, RV-6A N51PW Columbia TN
>
>
________________________________________________________________________________
From: | Earl_Schroeder <Earl_Schroeder(at)juno.com> |
Subject: | Re: Solid State Gyros |
Jon Goguen wrote:
>
> As I understood the description of this
>function from the TruTrak reps at Oshkosh, it differs from the pitch
>info provided by a classical ADI in an important way: when the ship
>changes attitude, you get an immediate indication of a change in pitch.
> However, once a new stable attitude is established the pitch indicator
>moves back to the horizon.
>
Jon,
Did the rep confirm this or is that your assumption? Since I am
considering a purchase, I'd really like to know. Thanks, Earl
________________________________________________________________________________
From: | Ken <klehman(at)albedo.net> |
Subject: | Re: ND two-lead alternator question |
Mickey
I love to see a real test - thank you.
May I ask if you tried the diode with the white band end towards the
alternator?
That would give the IG wire the opportunity to be at 0.6 volts less than
the battery assuming a little current flow into the IG connection. With
the diode the other way around it might just be defaulting to regulating
based on the voltage at the output terminal.
Ken
Mickey Coggins wrote:
>
>
>
>> Wire it up, run the alternator with solid wire in the
>> feeders to IG and L, then put a diode in series with
>> each wire one at a time. If insertion of the diode causes
>> bus voltage to rise by about 0.6 volts, then that wire
>> has been demonstrated to be a sense lead for the purpose
>> of providing more accurate control of bus voltage.
>>
>>
>
>Thanks for the info. I just did this, and I didn't see
>any difference with or without the diode. I used a
>1N 4004 diode. My battery only voltage was about 12.9v,
>and when cranking on the alternator with a 3000rpm
>electric hand drill, the voltage went up to about 14.3v
>within about 10-15 seconds. I could feel the load on
>the drill start out high, then gradually taper off.
>I'm measuring the voltage across the battery terminals.
>
>I agree that a schematic of this alternator's voltage
>regulator would be great!
>
>Thanks again for your help.
>
>Mickey
>
>
>
________________________________________________________________________________
From: | "SteinAir, Inc." <stein(at)steinair.com> |
Subject: | Solid State Gyros |
Not to sound harsh here, but I'm afraid your conclusion that an instrument
is "potentially dangerous" is rather dubious not having flown behind one.
Talk to the guys who've been flying behind these things (Yes, in IFR), and
they'll tell you it's superior to the old gyro AI in almost every way. It's
hard to get a very good indication of what it does from their ads and on a
bench, but fly behind one and you'll come away understanding how well it
does work. This subject get's re-hashed regularly, and a search of the
archives on the RV list will give you a load of info on it.
There are several reasons it's actually better. Pitch combined with
direction is far better.....with a traditional gyro, you can easily get it
to indicate a "nose high" attitude whilst the ship is descending, not so
with an ADI. Get slow, and the thing will tell you. Get upside down or in
a very unusual attitude and the thing tells you which way to move the stick
to correct it. Do a loop with it (the ADI) and it'll still be nuts on. Do a
loop with your RC Allen or Sigma-Tek and they will go nuts. "Absolute Pitch
Indication" isn't always worth as much as you might think (like the example
above of descending with your nose high).
Anyway, no flames intended here. It just seems to regularly come up lately,
and there are two distinct camps of people's opinions when it comes to the
ADI. Love it or hate it.....and.....from what I've seen those opinions are
almost 100% tied to whether or not the person really knows how they work and
has experienced them, or those who've flown behind one and those who
haven't. Don't get me wrong, I'm as old school as they come with this
stuff, but I try to keep an open mind before I make a final judgement on
something, especially something designed by Younkin (who's forgotten more
about this stuff than most of us will ever know).
Old practices and procedures are hard to change, but some of these
newfangled gizmos are in reality quite good compared to the old spinning
metal mass gyros. Before you think that I'm being biased, I'll say that I
have both in my airplane. I have the old vac gyros as well as the new
digital stuff (Dynon and TruTrak). Guess which I like better?! I also was
skeptical, but now I'm entirely convinced the new stuff is the way to go.
Just my 2 cents as usual!
Cheers,
Stein.
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Jon
> Goguen
> Sent: Thursday, September 29, 2005 10:44 AM
> To: aeroelectric-list(at)matronics.com
> Subject: Re: AeroElectric-List: Solid State Gyros
>
>
>
>
> I looked at the TruTrak ADI at Oshkosh, and came away very concerned
> that it's a potentially dangerous device. If you look at their ads,
> you'l see that they describe the pitch information provided as "gyro
> enhanced vertical speed". As I understood the description of this
> function from the TruTrak reps at Oshkosh, it differs from the pitch
> info provided by a classical ADI in an important way: when the ship
> changes attitude, you get an immediate indication of a change in pitch.
> However, once a new stable attitude is established the pitch indicator
> moves back to the horizon. Essentially, the device indicates something
> more akin to the derivative of pitch than pitch per se. Maybe there
> are some circumstances under which this is a good thing, but its not
> clear to me what they might be. If you don't have a horizon outside
> the ship, you cannot depend the TruTrak ADI to give an absolute pitch
> indication.
>
> Jon
>
> Jon Goguen
> jon.goguen(at)umassmed.edu
> Central Massachusetts
> Kitfox Series V Rotax 912S / N456JG (reserved)
> Complete except for electrics and avionics
> On Sep 28, 2005, at 8:59 PM, Fiveonepw(at)aol.com wrote:
________________________________________________________________________________
From: | Phil Birkelbach <phil(at)petrasoft.net> |
Subject: | Re: Solid State Gyros |
I sent Jon's note to TruTrak. I'll report when I get an answer from them.
I suspect that it is a missunderstanding on how the unit determines what
the pitch is. My guess is that it is integrating an acceleromter at the
same time that it is integrating a rate gyro to determine the pitch to
show. My Dynon has some similar features but it doesn't give wrong
information it just determines the information with a little different
methods than the mechanical ADI's. We'll see what TruTrak has to say.
Godspeed,
Phil Birkelbach - Houston Texas
RV-7 N727WB - Phase I
http://www.myrv7.com
Earl_Schroeder wrote:
>
>
>Jon Goguen wrote:
>
>
>
>>
>> As I understood the description of this
>>function from the TruTrak reps at Oshkosh, it differs from the pitch
>>info provided by a classical ADI in an important way: when the ship
>>changes attitude, you get an immediate indication of a change in pitch.
>> However, once a new stable attitude is established the pitch indicator
>>moves back to the horizon.
>>
>>
>>
>Jon,
>Did the rep confirm this or is that your assumption? Since I am
>considering a purchase, I'd really like to know. Thanks, Earl
>
>
>
>
________________________________________________________________________________
Subject: | Re: Solid State Gyros |
From: | "Matt Prather" <mprather(at)spro.net> |
It seems very surprising that the ADI works exactly as you described..
Instead, I suspect that as long as the airplane is stabilized in a descent
(negative vertical speed), the display will indicate a nose-down attitude,
and when stabilized in a climb, it will display a nose-up attitude. It
looks like the device uses VSI information to cancel slow-term gyro drift.
The only weird thing about this behavior is that there probably isn't a
pitch indication difference between stabilized level flight (vertical
speed=0) whether at Vmo or Vs.
Say you're are running flat out because ATC told you to keep your speed
up. The attitude indicator shows level flight. Then they tell you to
enter a hold, you decide to slow down (to save gas), so you pull power
back, and start to roll in nose-up trim to maintain altitude. Initially,
the ADI correctly indicates this higher pitch attitude. Finally, you get
down to loiter speed and the nose is actually at a much steeper pitch
attitude than when at Vmo. Once stabilized at the new pitch/speed
combination, the ADI will slowly indicate that the nose is returning to a
level atttitude.. That's the VSI 'enhanced' feature. I don't think this
is likely to cause control problems, though it is especially important to
keep the Airspeed Indicator in your scan.
I guess there is one other weird behavior.. If you take on a load of ice,
airspeed will suffer and eventually you won't be able to maintain
altitude, even with the nose pitched up to best L/D (Vy) attitude. So you
start to descend. I suspect the ADI will indicate a nose down attitude
even though you are actually pitched up.
Regards,
Matt-
>
>
> I looked at the TruTrak ADI at Oshkosh, and came away very concerned
> that it's a potentially dangerous device. If you look at their ads,
> you'l see that they describe the pitch information provided as "gyro
> enhanced vertical speed". As I understood the description of this
> function from the TruTrak reps at Oshkosh, it differs from the pitch
> info provided by a classical ADI in an important way: when the ship
> changes attitude, you get an immediate indication of a change in pitch.
> However, once a new stable attitude is established the pitch indicator
>
> moves back to the horizon. Essentially, the device indicates something
> more akin to the derivative of pitch than pitch per se. Maybe there
> are some circumstances under which this is a good thing, but its not
> clear to me what they might be. If you don't have a horizon outside
> the ship, you cannot depend the TruTrak ADI to give an absolute pitch
> indication.
>
> Jon
>
> Jon Goguen
> jon.goguen(at)umassmed.edu
> Central Massachusetts
> Kitfox Series V Rotax 912S / N456JG (reserved)
> Complete except for electrics and avionics
> On Sep 28, 2005, at 8:59 PM, Fiveonepw(at)aol.com wrote:
>
>>
>> Did you look at stuff by PCFlightSystems? Maybe they have something
>> you can
>> use. I use their PDA based EFIS/GPS Nav stuff as my main PFD/NAV
>> (VFR) and it
>> works quite nicely...
>>
>> http://pcflightsystems.com/
>>
>> Mark Phillips, RV-6A N51PW Columbia TN
>>
>>
>
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: ND two-lead alternator question |
>
>
> > Wire it up, run the alternator with solid wire in the
> > feeders to IG and L, then put a diode in series with
> > each wire one at a time. If insertion of the diode causes
> > bus voltage to rise by about 0.6 volts, then that wire
> > has been demonstrated to be a sense lead for the purpose
> > of providing more accurate control of bus voltage.
>
>Thanks for the info. I just did this, and I didn't see
>any difference with or without the diode. I used a
>1N 4004 diode. My battery only voltage was about 12.9v,
>and when cranking on the alternator with a 3000rpm
>electric hand drill, the voltage went up to about 14.3v
>within about 10-15 seconds. I could feel the load on
>the drill start out high, then gradually taper off.
>I'm measuring the voltage across the battery terminals.
>
>I agree that a schematic of this alternator's voltage
>regulator would be great!
>
>Thanks again for your help.
3000rpm is at the raggedy edge of minimum speed for
regulation at full output so perhaps your experiment
was incapable of yielding definitive data. You can
rig a 12 or 24 volt transformer to "boost" the line
voltage to the drill motor. Was this 3000 a measured
value or nameplate value?
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: ND two-lead alternator question |
>
> >Bob N wrote: Again, like the so called "OV Protection" built into the
> regulator
> > chip, there are reliability issues with using the same
> > chip to annunciate non-operation as well as control an alternator.
>
>
>I agree you should have a separate Lo/Hi voltage indicator but not for the
>reasons you state. You also address ND alternator reliability for which
>you have no knowledge of and should focus on facts and not your opinion.
I focus on nothing but facts George . . . my career
success absolutely depends on an artful exploitation
of facts.
>-The chance of an indication failure and alternator failure (of the kind
>that only exist in your dreams Bob) at the same time is unlikely. The lamp
>driver and detection is separate from the voltage regulator, even if the
>function is contained in the same chip. It is possible that a rare fault
>will happen in the first place and even more rare the indicator fails at
>the same time. The bulb is more likely to fail, but you can check it every
>time you turn your electrical system on before cranking the engine over.
>The idiot light will glow just like your car.
>
>-Second, the so called OV protection is more sophisticated than a so
>called crow bar.Also being on-board the alternator is reacts quicker and
>more precisely (despite what Bob says).
>Bob, you are talking about reliability issues, and you have no idea what
>you are talking about. You said you have an engineering degree and
>understand failure mode analysis and in particular those of the IC chips
>in ND alternators? Where did you go to school and what degree did you get?
>I went to LSU for under grad and UW for grad school.
You want to do dueling diplomas? Sorry, I can't help
you there. I do not have a degree. I bailed from second
semester calculus when the TA instructor (who could work
problems but couldn't teach) told us that 95% of everything
we needed to know about calculus as an engineer was contained
in 3 or 4 chapters of a 30 chapter book that took 15 semester
hours to slog through. When I checked it out with the head of
the math department the next morning, he said, "Son, the engineering
department says you need an education in math. I teach math. Yeah,
it's for math majors but I DO teach math. Take it or leave it."
I was a few hours short of being a junior, working full time,
raising two kids, had yet to take a real engineering course
and was learning more on my job than I was in school. That
was my last class at Wichita State University. They could
not provide me with what I needed.
My first consulting job was 1968 for Mobilizer
where I designed the electrics for a hospital patient
transporter that was being designed here in Wichita.
See:
http://www.aeroelectric.com/Pictures/Mobilizer_3s.jpg
The old guy on the prototype is my Dad who I was able to
remove and replace on the adjacent table without
laying a hand on him. The electrics for the machine
were no big deal but I did my first analog computer
and data acquisition system for measuring and
comparing the relative efficiencies of different
belts and drive trains. This was a few months after
I bailed from WSU. My lead on this program was
Ken Razak, a former dean who built WSU's engineering
department and left to do more interesting things.
He seemed reasonably happy with my performance. He
paid my invoices. I think I was hitting him for
about $10/hour back then). I'm still doing work for
him from time to time . . . for a whole lot more
than $10/hour! He's 87 years old and still looking
for interesting things to do.
You can beat on me all you wish with your diplomas.
I've got thousands of happy customers and dozens of
happy supervisors who would stand behind me. Your
diplomas are going to be a bit ragged by the time
your through whacking on all of us.
>What reliability data do you have? I will admit my info is anadotical, but
>it is backed up by conversations with Nippon Denso engineers, auto
>industry electrical service experts and the National Transportation Safety
>data base that tracks reliability of all aspects of automobiles, including
>electrical charging systems (alternators). Since there a millions ND
>alternators in service with no record of recalls, consumer complaint or
>safety related issues, such as fires, I would say that is pretty good
>statistics, not to mention the millions of ND alternators in industrial
>equipment, going 24/7 for year after year with no problem. What
>reliability info do you have? I know everyone gives Paul crap about not
>showing data, lets see your ND alternator reliability data, please.
>(facts: model, place, failure mode, indications and affect of failure)
George, this is the FAA no Bob talking about reliability
issues. If the FAA were looking over my shoulder for certifying an
IR alternator onto a type certificated airplane, they
would ask me how I propose to provide OV protection. OV
"protection" on the same chip with voltage control
would never fly with the FAA and there are good reasons
for that design goal even if you don't personally endorse
them. Please forward list of all the folks who worship at
the altar of anecdotal data, perhaps I can submit this as
part of my certification basis?
Please stop whacking at me or anyone else for pursuing
design goals that are different from yours. Please wire
your airplane as you see fit and based on any information
you consider relevant to your decision. Understand that
what I offer is advice based not on my opinions but on
facts and philosophies I have brought with me working
under the wings of Learjet (Electrical group lead
engineer on GP-180), Beech/Raytheon (Sr. Electronics
engineer 15+ years and now lead subject matter expert),
Electromech Technologies (only electron herder on staff
for 5 years and lead for 4 more) and 38+ years of
delivering design services to a clientele of what
I presume are happy customers . . . they keep coming
back for more of what I have to offer.
Bob . . . Summa cum gunk. HNTGYHDE
(Hammer'n tongs, get yer hands dirty engineer)
. . . who would rather make things work than sit in
a classroom hypothesizing about them.
________________________________________________________________________________
From: | "Carl Morgan" <zk-vii(at)blueyonder.co.uk> |
Subject: | VANs ND Alternator wiring |
Hi all,
I've been following the list for a few years and watched IR/OR/OV debates
with "interest".
Given the following assumption:
We have a VANs ND IR 60 Amp alternator (w/ internal OV protection) (3 wire +
ground). It is acceptable to us and we want an idiot light directly from
the alternator and no external OV sensing.
We want the light to come on with the main bus power, off during engine
running / battery charging. An emergency alternator 'off' control and
remote voltage sensing from the battery would be good if possible.
Can someone suggest a possible wiring solution that utilises the
functionality of the ND alternator (based on the LAMP/RED, IG/GREEN,
S/BLUE -
http://www.aeroelectric.com/Reference_Docs/Alternator_Data/ND_3-wire.jpg ).
Currently I seem to have VANs not using the full functionality and Bob on
principle not happy with recommending a non OV / IR solution. Anybody care
to offer a solution?
Thanks,
Carl
PS: This is part of a dual ALT, dual Battery (Z-14) configuration - the
second alt will be external OR, OV based. Both busses will have active
Voltage / Amp monitoring.
--
ZK-VII - RV 7A QB - wiring
Cromwell, New Zealand
--
________________________________________________________________________________
From: | "Frank Stringham" <fstringham(at)hotmail.com> |
Subject: | Re: ND two-lead alternator question |
Degrees degrees.............I have a few ( AS, BS, MBA) and I will give sway
to the man with facts, OJT, and tons of experience anytime. Now lets
see.................Bill Gates ......zero degrees, great idea, mucho grande
$$$$$$$$$$$$$$. We all know what BS stands for (Bull S***), and an MS is
just More of the Same, and PhD are just Piled Higher and Deeper.
So back to Bob's aeroelectric and still learning the wonderful world of
electronics, aircraft wiring, and panel installation.
Experiment all you want, even debate with your FACTS so we may decide for
ourselves what might work for us, but leave the degree home please..........
Frank @ SGU and SLC
>From: "Robert L. Nuckolls, III" <nuckollsr(at)cox.net>
>Reply-To: aeroelectric-list(at)matronics.com
>To: aeroelectric-list(at)matronics.com
>Subject: Re: AeroElectric-List: ND two-lead alternator question
>Date: Thu, 29 Sep 2005 17:09:05 -0500
>
>
>
>
> >
> > >Bob N wrote: Again, like the so called "OV Protection" built into the
> > regulator
> > > chip, there are reliability issues with using the same
> > > chip to annunciate non-operation as well as control an alternator.
> >
> >
> >I agree you should have a separate Lo/Hi voltage indicator but not for
>the
> >reasons you state. You also address ND alternator reliability for which
> >you have no knowledge of and should focus on facts and not your opinion.
>
> I focus on nothing but facts George . . . my career
> success absolutely depends on an artful exploitation
> of facts.
>
>
> >-The chance of an indication failure and alternator failure (of the kind
> >that only exist in your dreams Bob) at the same time is unlikely. The
>lamp
> >driver and detection is separate from the voltage regulator, even if the
> >function is contained in the same chip. It is possible that a rare fault
> >will happen in the first place and even more rare the indicator fails at
> >the same time. The bulb is more likely to fail, but you can check it
>every
> >time you turn your electrical system on before cranking the engine over.
> >The idiot light will glow just like your car.
> >
> >-Second, the so called OV protection is more sophisticated than a so
> >called crow bar.Also being on-board the alternator is reacts quicker and
> >more precisely (despite what Bob says).
>
>
>
>
>
> >Bob, you are talking about reliability issues, and you have no idea what
> >you are talking about. You said you have an engineering degree and
> >understand failure mode analysis and in particular those of the IC chips
> >in ND alternators? Where did you go to school and what degree did you
>get?
> >I went to LSU for under grad and UW for grad school.
>
> You want to do dueling diplomas? Sorry, I can't help
> you there. I do not have a degree. I bailed from second
> semester calculus when the TA instructor (who could work
> problems but couldn't teach) told us that 95% of everything
> we needed to know about calculus as an engineer was contained
> in 3 or 4 chapters of a 30 chapter book that took 15 semester
> hours to slog through. When I checked it out with the head of
> the math department the next morning, he said, "Son, the engineering
> department says you need an education in math. I teach math. Yeah,
> it's for math majors but I DO teach math. Take it or leave it."
>
> I was a few hours short of being a junior, working full time,
> raising two kids, had yet to take a real engineering course
> and was learning more on my job than I was in school. That
> was my last class at Wichita State University. They could
> not provide me with what I needed.
>
> My first consulting job was 1968 for Mobilizer
> where I designed the electrics for a hospital patient
> transporter that was being designed here in Wichita.
> See:
>
>http://www.aeroelectric.com/Pictures/Mobilizer_3s.jpg
>
> The old guy on the prototype is my Dad who I was able to
> remove and replace on the adjacent table without
> laying a hand on him. The electrics for the machine
> were no big deal but I did my first analog computer
> and data acquisition system for measuring and
> comparing the relative efficiencies of different
> belts and drive trains. This was a few months after
> I bailed from WSU. My lead on this program was
> Ken Razak, a former dean who built WSU's engineering
> department and left to do more interesting things.
> He seemed reasonably happy with my performance. He
> paid my invoices. I think I was hitting him for
> about $10/hour back then). I'm still doing work for
> him from time to time . . . for a whole lot more
> than $10/hour! He's 87 years old and still looking
> for interesting things to do.
>
> You can beat on me all you wish with your diplomas.
> I've got thousands of happy customers and dozens of
> happy supervisors who would stand behind me. Your
> diplomas are going to be a bit ragged by the time
> your through whacking on all of us.
>
> >What reliability data do you have? I will admit my info is anadotical,
>but
> >it is backed up by conversations with Nippon Denso engineers, auto
> >industry electrical service experts and the National Transportation
>Safety
> >data base that tracks reliability of all aspects of automobiles,
>including
> >electrical charging systems (alternators). Since there a millions ND
> >alternators in service with no record of recalls, consumer complaint or
> >safety related issues, such as fires, I would say that is pretty good
> >statistics, not to mention the millions of ND alternators in industrial
> >equipment, going 24/7 for year after year with no problem. What
> >reliability info do you have? I know everyone gives Paul crap about not
> >showing data, lets see your ND alternator reliability data, please.
> >(facts: model, place, failure mode, indications and affect of failure)
>
> George, this is the FAA no Bob talking about reliability
> issues. If the FAA were looking over my shoulder for certifying an
> IR alternator onto a type certificated airplane, they
> would ask me how I propose to provide OV protection. OV
> "protection" on the same chip with voltage control
> would never fly with the FAA and there are good reasons
> for that design goal even if you don't personally endorse
> them. Please forward list of all the folks who worship at
> the altar of anecdotal data, perhaps I can submit this as
> part of my certification basis?
>
> Please stop whacking at me or anyone else for pursuing
> design goals that are different from yours. Please wire
> your airplane as you see fit and based on any information
> you consider relevant to your decision. Understand that
> what I offer is advice based not on my opinions but on
> facts and philosophies I have brought with me working
> under the wings of Learjet (Electrical group lead
> engineer on GP-180), Beech/Raytheon (Sr. Electronics
> engineer 15+ years and now lead subject matter expert),
> Electromech Technologies (only electron herder on staff
> for 5 years and lead for 4 more) and 38+ years of
> delivering design services to a clientele of what
> I presume are happy customers . . . they keep coming
> back for more of what I have to offer.
>
> Bob . . . Summa cum gunk. HNTGYHDE
>
> (Hammer'n tongs, get yer hands dirty engineer)
>
> . . . who would rather make things work than sit in
> a classroom hypothesizing about them.
>
>
________________________________________________________________________________
From: | "Rodney Dunham" <rdunhamtn(at)hotmail.com> |
Subject: | OVP failure consequent to VR failure |
7.50 BARRACUDA_HEADER_FP56 RBL: Blacklist bl.spamcop
[Blocked - see <http://www.spamcop.net/bl.shtml?65.54.162.200>]
George,
I was reviewing a back issue of Aviation Safety magazine while doing my
business the other morning (yes, I keep them in a rack next to the john,
thank you very much) and noticed an article on the service bulletin
(SEB03-3A) warning of OV protection failure consequent to VR failure in the
VR600A manufactured by Electrosystems, Inc. This SB affects the 100 and 200
series Cessna aircraft.
It seems the VR600A's installation instructions called for removal of the
OEM (Cessna) installed over-voltage protection device. The VR600A has an
internal OVP module which was believed by the relevent engineers to be good
enough. Not so, it would appear. The AD calls for replacement of the PMA'd
VRs and reinstallation of the OEM overvoltage protection modules due to just
such failures as you consider only a lofty imagination of our fearless
leader!
Hey, let's keep the dialog civil. There's room here for diagreement without
diatribe.
Rodney in Tennessee
BS, MD, PPL / SKR, C172, C182, Sonex
________________________________________________________________________________
From: | "Rodney Dunham" <rdunhamtn(at)hotmail.com> |
Subject: | OVP failure consequent to VR failure |
7.50 BARRACUDA_HEADER_FP56 RBL: Blacklist bl.spamcop
[Blocked - see <http://www.spamcop.net/bl.shtml?65.54.162.200>]
George,
I was reviewing a back issue of Aviation Safety magazine while doing my
business the other morning (yes, I keep them in a rack next to the crapper,
thank you very much) and noticed an AD on alternators affecting multiple
single engine rides including almost all the Cessna line and some Beach
products as well. The AD was warning of OV protection failure consequent to
VR failure in the VR600 series VRs.
It seems the PMA'd VRs installation instructions called for removal of the
OEM (Cessna) installed over-voltage protection device. The PMA'd VRs had
internal OVP modules which were believed by the relevent engineers to be
good enough. Not so. The AD calls for removal of the PMA'd VRs and
reinstallation of the OEM overvoltage protection modules due to just such
failures as you consider only a lofty imagination our fearless leader!
Hey, let's keep the dialog civil. There's room here for diagreement without
diatribe.
Rodney in Tennessee
BS, MD, PPL / SKR, C172, C182, Sonex
________________________________________________________________________________
From: | N1deltawhiskey(at)aol.com |
Subject: | Re: ND two-lead alternator question |
Bob,
Good posting.
I too have gotten a little tired of those who would flaunt their college
degrees and awards of achievement as an indication that I should somehow listen
to
them because they know more than I do, or that someone else who does not have
such a degree.
My degree in electrical engineering taught me that there were many
knowledgeable people who were thought they knew a lot, but could not teach it.
Of
course, they acquired their jobs based on resumes, association with certain
institutions and the like, not on their ability to teach something. I sometimes
thought of Paul being one of those types, and one could probably put George there
too. It is also my perception that someone's ability to explain something
logically and intelligently is an indication of their actual understanding of the
subject.
Degrees and awards, for some people, do little more than feed their egos.
What a waste. I think what was the most beneficial for me is that I learned a
little better how to think, not what to think. I have never put myself forward
as an expert in much of anything, but I am not dumb either. I did not even
bother to go after my P.E. stamp, and if I had, I doubt I would use it.
Of course, I would surrender my degree and whatever I gained by spending the
time and effort to get it to be as economically productive as one of my
neighbors (well, within single digit miles, anyway). He happens to currently be
the
wealthiest man in the WORLD! And guess what - he never finished college
either. I wonder if there is an economics professor out there somewhere with an
ego big enough to suggest he could tell Mr. Gates how to accumulate wealth.
Guess as to whom I would listen to garner information on how to create wealth.
Anyway, keep on truckin'. An thanks for all the great insights shared over
the years I have been on this list.
Regards,
Doug Windhorn
In a message dated 29-Sep-05 15:13:48 Pacific Standard Time,
nuckollsr(at)cox.net writes:
>
> >Bob N wrote: Again, like the so called "OV Protection" built into the
> regulator
> > chip, there are reliability issues with using the same
> > chip to annunciate non-operation as well as control an alternator.
>
>
>I agree you should have a separate Lo/Hi voltage indicator but not for the
>reasons you state. You also address ND alternator reliability for which
>you have no knowledge of and should focus on facts and not your opinion.
I focus on nothing but facts George . . . my career
success absolutely depends on an artful exploitation
of facts.
>-The chance of an indication failure and alternator failure (of the kind
>that only exist in your dreams Bob) at the same time is unlikely. The lamp
>driver and detection is separate from the voltage regulator, even if the
>function is contained in the same chip. It is possible that a rare fault
>will happen in the first place and even more rare the indicator fails at
>the same time. The bulb is more likely to fail, but you can check it every
>time you turn your electrical system on before cranking the engine over.
>The idiot light will glow just like your car.
>
>-Second, the so called OV protection is more sophisticated than a so
>called crow bar.Also being on-board the alternator is reacts quicker and
>more precisely (despite what Bob says).
>Bob, you are talking about reliability issues, and you have no idea what
>you are talking about. You said you have an engineering degree and
>understand failure mode analysis and in particular those of the IC chips
>in ND alternators? Where did you go to school and what degree did you get?
>I went to LSU for under grad and UW for grad school.
You want to do dueling diplomas? Sorry, I can't help
you there. I do not have a degree. I bailed from second
semester calculus when the TA instructor (who could work
problems but couldn't teach) told us that 95% of everything
we needed to know about calculus as an engineer was contained
in 3 or 4 chapters of a 30 chapter book that took 15 semester
hours to slog through. When I checked it out with the head of
the math department the next morning, he said, "Son, the engineering
department says you need an education in math. I teach math. Yeah,
it's for math majors but I DO teach math. Take it or leave it."
I was a few hours short of being a junior, working full time,
raising two kids, had yet to take a real engineering course
and was learning more on my job than I was in school. That
was my last class at Wichita State University. They could
not provide me with what I needed.
My first consulting job was 1968 for Mobilizer
where I designed the electrics for a hospital patient
transporter that was being designed here in Wichita.
See:
http://www.aeroelectric.com/Pictures/Mobilizer_3s.jpg
The old guy on the prototype is my Dad who I was able to
remove and replace on the adjacent table without
laying a hand on him. The electrics for the machine
were no big deal but I did my first analog computer
and data acquisition system for measuring and
comparing the relative efficiencies of different
belts and drive trains. This was a few months after
I bailed from WSU. My lead on this program was
Ken Razak, a former dean who built WSU's engineering
department and left to do more interesting things.
He seemed reasonably happy with my performance. He
paid my invoices. I think I was hitting him for
about $10/hour back then). I'm still doing work for
him from time to time . . . for a whole lot more
than $10/hour! He's 87 years old and still looking
for interesting things to do.
You can beat on me all you wish with your diplomas.
I've got thousands of happy customers and dozens of
happy supervisors who would stand behind me. Your
diplomas are going to be a bit ragged by the time
your through whacking on all of us.
>What reliability data do you have? I will admit my info is anadotical, but
>it is backed up by conversations with Nippon Denso engineers, auto
>industry electrical service experts and the National Transportation Safety
>data base that tracks reliability of all aspects of automobiles, including
>electrical charging systems (alternators). Since there a millions ND
>alternators in service with no record of recalls, consumer complaint or
>safety related issues, such as fires, I would say that is pretty good
>statistics, not to mention the millions of ND alternators in industrial
>equipment, going 24/7 for year after year with no problem. What
>reliability info do you have? I know everyone gives Paul crap about not
>showing data, lets see your ND alternator reliability data, please.
>(facts: model, place, failure mode, indications and affect of failure)
George, this is the FAA no Bob talking about reliability
issues. If the FAA were looking over my shoulder for certifying an
IR alternator onto a type certificated airplane, they
would ask me how I propose to provide OV protection. OV
"protection" on the same chip with voltage control
would never fly with the FAA and there are good reasons
for that design goal even if you don't personally endorse
them. Please forward list of all the folks who worship at
the altar of anecdotal data, perhaps I can submit this as
part of my certification basis?
Please stop whacking at me or anyone else for pursuing
design goals that are different from yours. Please wire
your airplane as you see fit and based on any information
you consider relevant to your decision. Understand that
what I offer is advice based not on my opinions but on
facts and philosophies I have brought with me working
under the wings of Learjet (Electrical group lead
engineer on GP-180), Beech/Raytheon (Sr. Electronics
engineer 15+ years and now lead subject matter expert),
Electromech Technologies (only electron herder on staff
for 5 years and lead for 4 more) and 38+ years of
delivering design services to a clientele of what
I presume are happy customers . . . they keep coming
back for more of what I have to offer.
Bob . . . Summa cum gunk. HNTGYHDE
(Hammer'n tongs, get yer hands dirty engineer)
. . . who would rather make things work than sit in
a classroom hypothesizing about them.
________________________________________________________________________________
From: | GMC <gmcnutt(at)shaw.ca> |
Subject: | Re: Solid State Gyros |
Hi Jon,
I don't have my Trutrak yet because I am waiting for the autopilot
version. Initially I had some of the same reservations you are
expressing. If you want factual data call the company and they will
answer your concerns and questions. One thing that you may not be aware
of is the Trutrak ADI has a low airspeed warning for that nose high
descent you (and I) are worried about.
My understanding is that the little solid state gyros have a high drift
rate so they must be stabilized in roll by internal magnetometer or GPS
and in pitch by vertical speed. (-disclaimer I have not seen or flown
the Trutrak ADI.)
Analyze what you actually need to know when instrument flying, attitude
or flight path, in most cases we use the attitude indicator to establish
flight path that must be verified on other instruments. The Trutrak
shows flight path plus V/S and low airspeed indications. Zero pitch on
the ADI will be level flight at any speed, zero pitch on the attitude
indicator will be level flight at only one airspeed.
Jon Goguen wrote:
>
>Nonetheless, it doesn't give true attitude information, and could indicate negative
pitch during a decent
>with the nose high, or zero pitch when hanging from the prop, etc.
>
Your A/H would also be giving information that would require
interpretation and verification by reference to other instruments, my
understanding is yes the ADI would show descent plus an airspeed
warning, and.highly unlikely that you would be hanging from the prop but
if you did what would your horizon show, maybe wild gyrations?
> reason I think this instrument could be dangerous is because it may
>require one to do some extra thinking in unusual situations on the edge
>of real trouble.
>
The ADI has been reported to be easier to fly than a standard horizon
and presents more information on one instrument than the horizon so
there should be less chance of getting into trouble.
>
>How does it behave if the static port ices
>over? Seems that I would have no interpretable pitch information,
>
Good question, not sure what the gyros would show without a stabilizing
static input or if the old "break the glass face" will work, I would
presume that an iced up pitot would cause erroneous or no low speed
warning. In any case IFR aircraft normally have alternate static,
(another plus for Van's static ports versus a Piper pitot/static setup,
I cannot imagine them icing up in a RV aircraft mounted on the aft
narrowing fuselage).
Take care,
George in Langley B.C.
________________________________________________________________________________
Subject: | Re: ND two-lead alternator question |
From: | James H Nelson <rv9jim(at)juno.com> |
Bob,
That was well put. I use to hire engineers who were good in
school. However, give them a wrench and have them go solve a problem on
line-- most were lost. They had to be trained to do real world problem
solving, preferable with a good experienced mechanic at their side.
Jim Nelson
(have a degree but real world problem solving got my jobs)
________________________________________________________________________________
From: | "Ed Anderson" <eanderson(at)carolina.rr.com> |
Subject: | Re: Solid State Gyros |
Makes sense, most of the less expensive (less than thousands of $$) solid
state gyros have drift rates too high to be used for long term stability.
They are fine for short term stability (camera stabilization, wireless
mouse, etc) but need something like accelerometers, GPS and/or other
Directional Source to provide long term stability. I researched these gyros
when I was considering using one in a cheap wing leveler system - I decided
by the time you add the long term stabilization system it was no longer a
cheap solution {:>). However, as their quality improves and prices comes
down it will open up a entire new dimension in the price of autopilots.
Ed A
----- Original Message -----
From: "GMC" <gmcnutt(at)shaw.ca>
Subject: Re: AeroElectric-List: Solid State Gyros
>
>
> Hi Jon,
>
> I don't have my Trutrak yet because I am waiting for the autopilot
> version. Initially I had some of the same reservations you are
> expressing. If you want factual data call the company and they will
> answer your concerns and questions. One thing that you may not be aware
> of is the Trutrak ADI has a low airspeed warning for that nose high
> descent you (and I) are worried about.
> My understanding is that the little solid state gyros have a high drift
> rate so they must be stabilized in roll by internal magnetometer or GPS
> and in pitch by vertical speed. (-disclaimer I have not seen or flown
> the Trutrak ADI.)
>
> Analyze what you actually need to know when instrument flying, attitude
> or flight path, in most cases we use the attitude indicator to establish
> flight path that must be verified on other instruments. The Trutrak
> shows flight path plus V/S and low airspeed indications. Zero pitch on
> the ADI will be level flight at any speed, zero pitch on the attitude
> indicator will be level flight at only one airspeed.
>
> Jon Goguen wrote:
>
>>
>>
>>Nonetheless, it doesn't give true attitude information, and could indicate
>>negative pitch during a decent
>>with the nose high, or zero pitch when hanging from the prop, etc.
>>
> Your A/H would also be giving information that would require
> interpretation and verification by reference to other instruments, my
> understanding is yes the ADI would show descent plus an airspeed
> warning, and.highly unlikely that you would be hanging from the prop but
> if you did what would your horizon show, maybe wild gyrations?
>
>> reason I think this instrument could be dangerous is because it may
>>require one to do some extra thinking in unusual situations on the edge
>>of real trouble.
>>
> The ADI has been reported to be easier to fly than a standard horizon
> and presents more information on one instrument than the horizon so
> there should be less chance of getting into trouble.
>
>>
>>How does it behave if the static port ices
>>over? Seems that I would have no interpretable pitch information,
>>
> Good question, not sure what the gyros would show without a stabilizing
> static input or if the old "break the glass face" will work, I would
> presume that an iced up pitot would cause erroneous or no low speed
> warning. In any case IFR aircraft normally have alternate static,
> (another plus for Van's static ports versus a Piper pitot/static setup,
> I cannot imagine them icing up in a RV aircraft mounted on the aft
> narrowing fuselage).
>
>
> Take care,
>
> George in Langley B.C.
>
>
>
________________________________________________________________________________
From: | "Dave Morris \"BigD\"" <BigD(at)DaveMorris.com> |
Subject: | Re: Solid State Gyros |
That's what I'm doing with my own home-grown system. Assuming that DEGREES
of pitch and bank are not nearly as important as RATE of CLIMB and RATE of
TURN, I am not using any gyros at all, but using the GPS input to determine
rate of turn and the Rocky Mountain MicroEncoder input to determine rate of
climb, and then displaying those on an AH, along with a moving map and HSI.
Equipped with an 8" touchscreen, you can touch any airport and it will not
only give you heading, distance, and time to arrival, but if the autopilot
is engaged, will fly there at whatever altitude you tell it. The airspeed
indicator reads from a config file to display all your V speeds. System
also includes a magnetic compass (RMI) interface, so it can instantaneously
calculate actual winds information from ground speed (GPS), airspeed (RMI),
ground track (RMI) and magnetic heading (RMI).
Another bold assumption I'm making is that the heading-hold autopilot will
also act as a wing-leveler, whereas an input from a Smart Level OEM module
will detect non-coordinated roll deviations that can also be fed into the
wing-leveler.
All for under $2000
All still theoretical because my Dragonfly isn't flying yet, but I hope to
be in 2006.
Dave Morris
www.MyGlassCockpit.com
At 10:58 PM 9/29/2005, you wrote:
>
>
>Hi Jon,
>
>I don't have my Trutrak yet because I am waiting for the autopilot
>version. Initially I had some of the same reservations you are
>expressing. If you want factual data call the company and they will
>answer your concerns and questions. One thing that you may not be aware
>of is the Trutrak ADI has a low airspeed warning for that nose high
>descent you (and I) are worried about.
>My understanding is that the little solid state gyros have a high drift
>rate so they must be stabilized in roll by internal magnetometer or GPS
>and in pitch by vertical speed. (-disclaimer I have not seen or flown
>the Trutrak ADI.)
>
>Analyze what you actually need to know when instrument flying, attitude
>or flight path, in most cases we use the attitude indicator to establish
>flight path that must be verified on other instruments. The Trutrak
>shows flight path plus V/S and low airspeed indications. Zero pitch on
>the ADI will be level flight at any speed, zero pitch on the attitude
>indicator will be level flight at only one airspeed.
>
>Jon Goguen wrote:
>
>
> >
> >Nonetheless, it doesn't give true attitude information, and could
> indicate negative pitch during a decent
> >with the nose high, or zero pitch when hanging from the prop, etc.
> >
________________________________________________________________________________
From: | "bob noffs" <icubob(at)newnorth.net> |
hi all,
i have bobs book but i was looking for a detailed ''how to'' set of directions
for building a comm antenna. bobs drawings leave too much to my imagination
and i end up with more questions than when i started . i am not at all familiar
with electronics. that i can even send this e mail is a miracle. anything on
a web site anyone knows of? from bobs book it seems that the antenna is very
basic stuff but i need more help shopping for parts for one thing.
i was just looking and thinking about the best place for my fuse panel. i have
no need to access the panel in flight but it still seems anywhere i put it i
will be at least be under the panel , half in the airplanes door, and holding
a flashlight in my mouth. now i am thinking those individual fuse holders next
to the switch or instrument would be in every way more convenient. never have
had a pleasant memory of changing a fuse in a car!
anyone's thoughts on either of these subjects would be appreciated.
bob noffs
________________________________________________________________________________
Subject: | Re: Cage horizon when powering up ? |
>>A buddy (who is also a test pilo)t advised us to always cage the horizon
>>prior to flipping on the master switch. This is supposed to provide a
>>longer service life.
>>What is your opinion ? Is this advice worth a line in the start up check
>>list, or is it just another hangar tale ?
>>
>>
>>
>
> I've not heard this before. I'll call some instrument shops
> and ask. I had an airplane in my rental fleet where we
> recommended caging the gyro for parking and uncaging at
> startup to speed up erection times . . . this was a suggestion
> of the aircraft's owner. Never did test the premise to
> see if it made a difference. Was this a new gyro? What does
> the manufacturer suggest in the installation data?
>
> I don't think we've got a single airplane in the club that
> even offers the manual caging capability. My initial reaction
> is that it's probably more myth than fact.
>
>
Hi Bob and all,
To cage or not to cage before powering up our electric gyro ?
Do you happen to have any more information ?
Thanks,
Regards,
Gilles Thesee
Grenoble, France
http://contrails.free.fr
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: Cage horizon when powering up ? |
><Gilles.Thesee@ac-grenoble.fr>
>
>
> >>A buddy (who is also a test pilo)t advised us to always cage the horizon
> >>prior to flipping on the master switch. This is supposed to provide a
> >>longer service life.
> >>What is your opinion ? Is this advice worth a line in the start up check
> >>list, or is it just another hangar tale ?
> >>
> >>
> >>
> >
> > I've not heard this before. I'll call some instrument shops
> > and ask. I had an airplane in my rental fleet where we
> > recommended caging the gyro for parking and uncaging at
> > startup to speed up erection times . . . this was a suggestion
> > of the aircraft's owner. Never did test the premise to
> > see if it made a difference. Was this a new gyro? What does
> > the manufacturer suggest in the installation data?
> >
> > I don't think we've got a single airplane in the club that
> > even offers the manual caging capability. My initial reaction
> > is that it's probably more myth than fact.
> >
> >
>
>Hi Bob and all,
>
>To cage or not to cage before powering up our electric gyro ?
>Do you happen to have any more information ?
I've talk to two ol' instrument mechanics with square
glasses who said about the same thing. Manufacturers
of gyros have published various admonitions for use of their
products to avoid unnecessary stresses and/or avoid obvious
hazards to damage. There's no consistent thread among them
except that the same items keep popping up from time to time.
They were aware of no gyro products that would exhibit
a demonstrably longer service life in a non-aerobatic
aircraft based on caging habits of the pilot. Some gyros
would erect faster if uncaged after power up but even that
"benefit" was marginally useful . . . there were no properly
operating gyros that wouldn't be fully stood up by the time
the airplane was ready for takeoff no matter how it was
oriented before power up. I'll keep nosing around.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: ND two-lead alternator question |
>
>
> > 3000rpm is at the raggedy edge of minimum speed for
> > regulation at full output so perhaps your experiment
> > was incapable of yielding definitive data. You can
> > rig a 12 or 24 volt transformer to "boost" the line
> > voltage to the drill motor. Was this 3000 a measured
> > value or nameplate value?
>
>Nameplate value. I'll see if I can find a way to spin
>it faster. I need a new drill anyway. Thanks!
Anything faster in a drill motor will be rare. Most
drills of greater capacity get "more powerful" by
gearing down for torque as a trade off for speed.
I'll suggest you get a small AC motor with a pulley
on it. Look for a 2-pole (3650 rpm) as opposed to
4-pole (1750 rpm). Of course, my choosing pulley sizes,
you can use the 4-pole motor too. You can mount the motor
to the bench with c-clamps and hand-hold the alternator for
the purposes of conducting the experiment. We're not
interested in performance under big loads, only
behavior at speeds above minimum speed for regulation
with a few amps load.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: ND two-lead alternator question |
>
>
> It is also my perception that someone's ability to explain something
>logically and intelligently is an indication of their actual understanding
>of the
>subject.
Exactly. The few times I've been tasked with hiring an
engineer, I was more interested in seeing his workbench
than I was in reading a resume. When I hired techs, I was
fortunate enough to be serving on the curriculum advisory board
for the Hutchinson Jr. College engineering technology
school. I'd call Earl up near the end of the semester
and ask for the names of his top 5 graduates. I think I
hired 4 kids out of his program and was never disappointed.
If you can't see their workbench, then talk to their teacher(s).
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: VANs ND Alternator wiring |
>
>
>Hi all,
>
>I've been following the list for a few years and watched IR/OR/OV debates
>with "interest".
>
>Given the following assumption:
>
>We have a VANs ND IR 60 Amp alternator (w/ internal OV protection) (3 wire +
>ground). It is acceptable to us and we want an idiot light directly from
>the alternator and no external OV sensing.
>
>We want the light to come on with the main bus power, off during engine
>running / battery charging. An emergency alternator 'off' control and
>remote voltage sensing from the battery would be good if possible.
>
>Can someone suggest a possible wiring solution that utilises the
>functionality of the ND alternator (based on the LAMP/RED, IG/GREEN,
>S/BLUE -
>http://www.aeroelectric.com/Reference_Docs/Alternator_Data/ND_3-wire.jpg ).
>
>Currently I seem to have VANs not using the full functionality and Bob on
>principle not happy with recommending a non OV / IR solution. Anybody care
>to offer a solution?
If you wire Van's offering per Van's instructions, you'll get
an installation that will operate exactly as Van says it will.
What we're debating is how does one integrate the modern
internally regulated alternator into a aircraft under the
traditional design goals for (a) absolute control by the pilot
using a panel switch that can be operated any time without
risk to the system or its components and (b) over-voltage protection
to stave off effects of an admittedly rare but nonetheless
catastrophic regulator failure.
There are builders and advisors to builders who have opined
that these design goals are archaic, unnecessary or even
silly, Van's included. I've got no problem with that as long
as the advisee UNDERSTANDS and accepts the tradeoffs for
adopting the new paradigm in aircraft electrical power
generation. I have made it my personal goal to deduce a
way to incorporate the modern technology under the old
design goals.
Unfortunately, this task requires data taken from manufacturer's
data sheets or testing done in the lab. Manufacturer's data
is difficult if not impossible to access and the lab I need
is outfitted with a 10 hp variable speed drive stand and
load-banks. I took on a consulting task yesterday with one of my
old employers who has such equipment standing idle 95% of
the time. I'm going to see if I can trade some gray matter
dump for lab time. We'll get there. It just takes time.
In the mean time. Wire any product of you choice per the
manufacturer's instructions and truck on with your project.
Anything we deduce from the planned experiments will be
easily added enhancements to existing installations. There's
no reason to slow progress on your project or loose any
sleep over it either.
Bob . . .
>Thanks,
>
>Carl
>
>PS: This is part of a dual ALT, dual Battery (Z-14) configuration - the
>second alt will be external OR, OV based. Both busses will have active
>Voltage / Amp monitoring.
>
>--
>ZK-VII - RV 7A QB - wiring
>Cromwell, New Zealand
>--
>
>
>--
>
>
>-- incoming mail is certified Virus Free.
Bob . . .
--------------------------------------------------------
< Throughout history, poverty is the normal condition >
< of man. Advances which permit this norm to be >
< exceeded -- here and there, now and then -- are the >
< work of an extremely small minority, frequently >
< despised, often condemned, and almost always opposed >
< by all right-thinking people. Whenever this tiny >
< minority is kept from creating, or (as sometimes >
< happens) is driven out of a society, the people >
< then slip back into abject poverty. >
< >
< This is known as "bad luck". >
< -Lazarus Long- >
<------------------------------------------------------>
http://www.aeroelectric.com
________________________________________________________________________________
From: | "bob noffs" <icubob(at)newnorth.net> |
hi all,
just came from my study[the bathroom] and it occurred to me that if i use individual
fuse holders in the panels then every wire that runs from the bus bar to
that fuse is unprotected from a short. if this is true that is enough to rule
that out?
bob noffs
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
>
> hi all,
> i have bobs book but i was looking for a detailed ''how to'' set of
> directions for building a comm antenna. bobs drawings leave too much to
> my imagination and i end up with more questions than when i started . i
> am not at all familiar with electronics. that i can even send this e
> mail is a miracle. anything on a web site anyone knows of? from bobs book
> it seems that the antenna is very basic stuff but i need more help
> shopping for parts for one thing.
What is your goal for this effort? If you're attempting to save over the
cost of a purchased antenna, then you should first assign some $time$
value to your present abilities. Let's say you've pegged your contribution
to the project at $7/hour. A commercial, ready to bolt on antenna can
be had for as little as $50. See:
http://www.aircraftspruce.com/catalog/avpages/av534.php
and a really nice one for under $100. See:
http://www.aircraftspruce.com/catalog/avpages/com_comant.php
There's no way I could duplicate the techniques used to
craft a $100 antenna in my shop so let's talk about the
$50 antenna. At $7/hour to build this antenna, you need to
purchase materials (say $15) and then finish the task in
about 5 hours. You're already 20-30 minutes into the program
just by opening this dialog.
Bottom line is that nobody saves money by building from
scratch.
An alternative goal is to achieve some understanding of
antenna operation and construction along with the personal
pride for having mastered some new technology and skills.
Now, considerations for $time$ are pushed way back on the
stove . . . education is always EXPENSIVE.
There are two aspects to antenna fabrication. Electrical
ones and mechanical ones. Electrically, you need a 22"
piece of metal to stick out of your fuselage relatively
clear of other obstructions. Mechanically, it needs to
be robust enough to withstand the rigors of aircraft
service. The installation shouldn't cause damage to your
airplane (you may need doublers). And it needs to utilize
techniques that are available to you in your shop.
I could walk out to my shop right now and cut a base
out of Delrin, machine an adapter drilled for 3/16"
stainless rod, silver solder the rod into the adapter,
bend the rod at some rakish angle with an eye toward
adding a fox tail . . . and I'm done. Except for a trip
to the Yard to pick up a piece of stainless, I could
probably have all that done in 2-3 hours. I would end
up with a perfectly performing antenna that looked like
it was built in my shop and had an investment of about
5 to 10 times what the commercial equivalent part would
cost.
I'm not trying to dissuade you from either course of
action. I'm only suggesting that you consider the
return on investment for both routes. Make your
decision based on goals you've set for your
activities what skills and tools you can bring to
the effort. My shop has a lathe in it. Your approach
to building the parts might take the hacksaw, band
saw and belt sander approach. You can produce
equally good performing parts but with more hours
and risks for spoilage.
This is why the DIY antenna descriptions in the
'Connection are so vague. I had no way to anticipate
the tools, skill set, and project goals for all
the builders. The best one can hope to do as a
writer is plant seeds of an idea that a few builders
can water and run with while adapting it to their own
tools and skill sets.
So, if you've decided you want to build an antenna,
your questions need to be more specific about how
to tackle details of its construction. You need to
formulate questions that mirror your access
tools and materials such that folks here on the
list have a good mental image of your working
environment and the level of assistance you're
needing to understand the fabrication steps.
> i was just looking and thinking about the best place for my fuse panel.
> i have no need to access the panel in flight but it still seems anywhere
> i put it i will be at least be under the panel , half in the airplanes
> door, and holding a flashlight in my mouth. now i am thinking those
> individual fuse holders next to the switch or instrument would be in
> every way more convenient. never have had a pleasant memory of changing a
> fuse in a car!
The advantage of the fuse blocks is that they provide
multiple power distribution taps off of a pre-fabricated
bus bar. Individual fuse holders scattered around the
airplane don't fill the bill. The likelihood of EVER
needing to replace a fuse in your airplane is smaller
than for your car. Use the fuse block, mount wherever
you have space and know that there are always some
things on airplanes that are extremely difficult to
work on. Those items need to be limited to stuff that
is seldom touched which includes fuse blocks.
I met a builder at a fly-in who had to dismount his
engine an hoist it up and forward to change his oil
filter . . . bad deal but the least of several
evils.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: ND two-lead alternator question |
>
>
> >>> 3000rpm is at the raggedy edge of minimum speed for
> >>> regulation at full output so perhaps your experiment
> >>> was incapable of yielding definitive data. You can
> >>> rig a 12 or 24 volt transformer to "boost" the line
> >>> voltage to the drill motor. Was this 3000 a measured
> >>> value or nameplate value?
> >>
> >>Nameplate value. I'll see if I can find a way to spin
> >>it faster. I need a new drill anyway. Thanks!
> >
> >
> > Anything faster in a drill motor will be rare. Most
> > drills of greater capacity get "more powerful" by
> > gearing down for torque as a trade off for speed.
>
>Yep - found this out this morning at the hardware store!
>
> > I'll suggest you get a small AC motor with a pulley
> > on it. Look for a 2-pole (3650 rpm) as opposed to
> > 4-pole (1750 rpm). Of course, my choosing pulley sizes,
> > you can use the 4-pole motor too. You can mount the motor
> > to the bench with c-clamps and hand-hold the alternator for
> > the purposes of conducting the experiment. We're not
> > interested in performance under big loads, only
> > behavior at speeds above minimum speed for regulation
> > with a few amps load.
>
>I went to the junkyard and found a 5" pulley that I
>thought I would use attached to the drill. The problem
>is that the drill (600 watts) does not have enough
>power to turn the alternator fast enough. I can go
>back on Monday to see if I can find an old AC motor.
>
>Of course, another option is to just hook up both
>my L and IG terminals to the bus, and hope that one
>of them does have a sense function. If I weren't
>waiting for parts for my engine, this would probably
>be the tack that I would take. I now have a choice,
>play with my alternator, or work on my fiberglass.
>Not a difficult decision!
Whoops! Perhaps I lost sight of your goal. you
seem belabored of the notion that one must KNOW
if L or IG is a sense lead. If all you're wanting
to do is hook it up so that it will work, then
hook IG directly to the bus. Hook L to the bus
through a lamp paralleled with a 150 ohm resistor
and be done with it. This is the industry standard
installation cars for decades and it WILL function.
Further, it matters not WHERE the sensing is done,
IG, L or B-lead.
I thought the purpose of your experiment was to
determine IF the regulator in your alternator was
taking advantage of some remote sense capability.
This is good data to have and we're all interested
in your experiment but I'll suggest that knowing
the answer won't have any useful effect on your
installation choices or performance of the finished
system.
Please continue with the experiment if you're
enjoying the opportunity for discovery but if you're
strapped for time then know that the outcome of
your experiments will have no practical effects
on your installation decisions. I am especially
appreciative of your efforts because its a solid
demonstration of the value of data taken from
the repeatable experiment no matter how crude
the setup. What you're doing and the spirit
under which it's conducted is a core component
of good science. I'll bet Carl Sagan would be
proud of you . . . you're doing just what he
would have suggested.
Bob . . .
________________________________________________________________________________
From: | "John Solecki" <jsolecki(at)sympatico.ca> |
Subject: | Re: ND two-lead alternator question |
These last series of comments remind me of the exchange between the Wizard &
the Scarecrow near the end of the movie
I can't remember it verbatim but as I recall the Scarecrow had gone to see
Wizard to get a brain. The wizard replied that wasn't possible and he
couldn't give him a brain but he what he could give him was a diploma and
virtually no one would know the difference.
My aircraft project has been put on hold until I have more free time but I
continue to subscribe to the AeroElectric List because of Robert Nuckolls.
I enjoy reading his replies to people's questions and his approach to
problems. It helps me deal with the engineering problems I deal with every
day.
Bob gives an extraordinary amount of his time and knowledge away for free
because of his love of aviation ( I guess) and a genuine desire to assist
his fellow enthusiasts; certainly not because he's getting rich billing out
his consulting time for the answers.
I cannot get over the number of people who vehemently attack his efforts.
There's a big difference between accountability and abuse and I wish
responders would bear this in mind.
John Solecki
Toronto
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckollsr(at)cox.net>
Subject: Re: AeroElectric-List: ND two-lead alternator question
>
>>Bob, you are talking about reliability issues, and you have no idea what
>>you are talking about. You said you have an engineering degree and
>>understand failure mode analysis and in particular those of the IC chips
>>in ND alternators? Where did you go to school and what degree did you get?
>>I went to LSU for under grad and UW for grad school.
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
>
>hi all,
>just came from my study[the bathroom] and it occurred to me that if i use
>individual fuse holders in the panels then every wire that runs from the
>bus bar to that fuse is unprotected from a short. if this is true that is
>enough to rule that out?
Very good! You're exactly right. My all time best
teacher NEVER directly answered a question I might
have asked. He always asked me questions that went
to underlying simple-ideas that supported the answer
I was seeking. More often than not, I would ultimately
discover the answer I was seeking by assembling what
I already knew. It's a simple but sometimes tedious
task but it's the way to true understanding as opposed
to blind acceptance of process.
Bob . . .
________________________________________________________________________________
From: | "Steve Hunt" <stephen.hunt19(at)btinternet.com> |
Subject: | Re: ND two-lead alternator question |
Hear Hear!
----- Original Message -----
From: "John Solecki" <jsolecki(at)sympatico.ca>
Subject: Re: AeroElectric-List: ND two-lead alternator question
>
>
> These last series of comments remind me of the exchange between the Wizard
> &
> the Scarecrow near the end of the movie
> I can't remember it verbatim but as I recall the Scarecrow had gone to see
> Wizard to get a brain. The wizard replied that wasn't possible and he
> couldn't give him a brain but he what he could give him was a diploma and
> virtually no one would know the difference.
>
> My aircraft project has been put on hold until I have more free time but I
> continue to subscribe to the AeroElectric List because of Robert Nuckolls.
> I enjoy reading his replies to people's questions and his approach to
> problems. It helps me deal with the engineering problems I deal with every
> day.
> Bob gives an extraordinary amount of his time and knowledge away for free
> because of his love of aviation ( I guess) and a genuine desire to assist
> his fellow enthusiasts; certainly not because he's getting rich billing
> out
> his consulting time for the answers.
> I cannot get over the number of people who vehemently attack his efforts.
> There's a big difference between accountability and abuse and I wish
> responders would bear this in mind.
>
> John Solecki
> Toronto
>
>
> ----- Original Message -----
> From: "Robert L. Nuckolls, III" <nuckollsr(at)cox.net>
> To:
> Subject: Re: AeroElectric-List: ND two-lead alternator question
>
>
>>
>>>Bob, you are talking about reliability issues, and you have no idea what
>>>you are talking about. You said you have an engineering degree and
>>>understand failure mode analysis and in particular those of the IC chips
>>>in ND alternators? Where did you go to school and what degree did you
>>>get?
>>>I went to LSU for under grad and UW for grad school.
>>
>
>
>
________________________________________________________________________________
From: | N5SL <nfivesl(at)yahoo.com> |
Subject: | Re: Was antennas Now Fuse Block Location |
Hi Bob:
I'm a real novice at this and have only had Bob's book for a week so take my advice
for what it's worth. I installed my fuse block with a hinge under the panel.
It swings down for access. I haven't installed any wires yet, but I plan
to run them neatly with enough coil the back to let it swing freely. I can't
take credit for it since another builder gave me the idea, but here are a
few photos of what I have done so far:
http://www.cooknwithgas.com/9_23_05_Main_Bus.JPG
and
http://www.cooknwithgas.com/9_23_05_Main_Bus_back.JPG
I have source information on the fuse block if you need it. I hope this helps,
Scott Laughlin
601XL/Corvair
www.cooknwithgas.com
bob noffs wrote:
hi all,
i was just looking and thinking about the best place for my fuse panel.
---------------------------------
Click here to donate to the Hurricane Katrina relief effort.
________________________________________________________________________________
From: | "David Henderson" <wf-k(at)mindspring.com> |
Subject: | Re: Was antennas Now Fuse Block Location |
Loved the pictures, great work! You let it swing down on demand but how is
it stowed? A magnet? A hook?
Dave Henderson RV-7 finishing kit
N925LW (Lord Willing)
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of N5SL
Subject: AeroElectric-List: Re: Was antennas Now Fuse Block Location
Hi Bob:
I'm a real novice at this and have only had Bob's book for a week so take my
advice for what it's worth. I installed my fuse block with a hinge under
the panel. It swings down for access. I haven't installed any wires yet,
but I plan to run them neatly with enough coil the back to let it swing
freely. I can't take credit for it since another builder gave me the
idea, but here are a few photos of what I have done so far:
http://www.cooknwithgas.com/9_23_05_Main_Bus.JPG
and
http://www.cooknwithgas.com/9_23_05_Main_Bus_back.JPG
I have source information on the fuse block if you need it. I hope this
helps,
Scott Laughlin
601XL/Corvair
www.cooknwithgas.com
bob noffs wrote:
hi all,
i was just looking and thinking about the best place for my fuse panel.
---------------------------------
Click here to donate to the Hurricane Katrina relief effort.
________________________________________________________________________________
From: | "Dave Morris \"BigD\"" <BigD(at)DaveMorris.com> |
Subject: | Re: Was antennas Now Fuse Block Location |
I was considering something like this to allow access to the fuse block
from outside the aircraft using a small door, but worried about the bending
of the wires introducing undetectable failures under the insulation. Since
my instrument panel is canopy-mounted, I have to implement some coiled
wires myself, but the canopy hinge operates over a much larger distance and
doesn't seem as failure-prone as a fuse block on a small door.
Dave Morris
At 12:36 PM 9/30/2005, you wrote:
>
>
>Loved the pictures, great work! You let it swing down on demand but how is
>it stowed? A magnet? A hook?
>
>Dave Henderson RV-7 finishing kit
>N925LW (Lord Willing)
>
>-----Original Message-----
>From: owner-aeroelectric-list-server(at)matronics.com
>[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of N5SL
>To: aeroelectric-list(at)matronics.com
>Subject: AeroElectric-List: Re: Was antennas Now Fuse Block Location
>
>
>Hi Bob:
>
>I'm a real novice at this and have only had Bob's book for a week so take my
>advice for what it's worth. I installed my fuse block with a hinge under
>the panel. It swings down for access. I haven't installed any wires yet,
>but I plan to run them neatly with enough coil the back to let it swing
>freely. I can't take credit for it since another builder gave me the
>idea, but here are a few photos of what I have done so far:
>
>http://www.cooknwithgas.com/9_23_05_Main_Bus.JPG
>
>and
>
>http://www.cooknwithgas.com/9_23_05_Main_Bus_back.JPG
>
>I have source information on the fuse block if you need it. I hope this
>helps,
>
>Scott Laughlin
>601XL/Corvair
>www.cooknwithgas.com
>
>
>bob noffs wrote:
>
>hi all,
>i was just looking and thinking about the best place for my fuse panel.
>
>
>---------------------------------
> Click here to donate to the Hurricane Katrina relief effort.
>
>
________________________________________________________________________________
From: | "Ed Anderson" <eanderson(at)carolina.rr.com> |
Subject: | Re: Solid State Gyros |
Great looking system, Dave. Impressive integration of components - took a
lot of time and research I am certain. I will be interested to hear how the
in-flight tests go.
Best of Luck with the project.
Ed Anderson
Rv-6A N494BW Rotary Powered
Matthews, NC
----- Original Message -----
From: "Dave Morris "BigD"" <BigD(at)DaveMorris.com>
Subject: Re: AeroElectric-List: Solid State Gyros
>
>
> That's what I'm doing with my own home-grown system. Assuming that
> DEGREES
> of pitch and bank are not nearly as important as RATE of CLIMB and RATE of
> TURN, I am not using any gyros at all, but using the GPS input to
> determine
> rate of turn and the Rocky Mountain MicroEncoder input to determine rate
> of
> climb, and then displaying those on an AH, along with a moving map and
> HSI.
>
> Equipped with an 8" touchscreen, you can touch any airport and it will not
> only give you heading, distance, and time to arrival, but if the autopilot
> is engaged, will fly there at whatever altitude you tell it. The airspeed
> indicator reads from a config file to display all your V speeds. System
> also includes a magnetic compass (RMI) interface, so it can
> instantaneously
> calculate actual winds information from ground speed (GPS), airspeed
> (RMI),
> ground track (RMI) and magnetic heading (RMI).
>
> Another bold assumption I'm making is that the heading-hold autopilot will
> also act as a wing-leveler, whereas an input from a Smart Level OEM module
> will detect non-coordinated roll deviations that can also be fed into the
> wing-leveler.
>
> All for under $2000
>
> All still theoretical because my Dragonfly isn't flying yet, but I hope to
> be in 2006.
>
> Dave Morris
> www.MyGlassCockpit.com
>
>
> At 10:58 PM 9/29/2005, you wrote:
>>
>>
>>Hi Jon,
>>
>>I don't have my Trutrak yet because I am waiting for the autopilot
>>version. Initially I had some of the same reservations you are
>>expressing. If you want factual data call the company and they will
>>answer your concerns and questions. One thing that you may not be aware
>>of is the Trutrak ADI has a low airspeed warning for that nose high
>>descent you (and I) are worried about.
>>My understanding is that the little solid state gyros have a high drift
>>rate so they must be stabilized in roll by internal magnetometer or GPS
>>and in pitch by vertical speed. (-disclaimer I have not seen or flown
>>the Trutrak ADI.)
>>
>>Analyze what you actually need to know when instrument flying, attitude
>>or flight path, in most cases we use the attitude indicator to establish
>>flight path that must be verified on other instruments. The Trutrak
>>shows flight path plus V/S and low airspeed indications. Zero pitch on
>>the ADI will be level flight at any speed, zero pitch on the attitude
>>indicator will be level flight at only one airspeed.
>>
>>Jon Goguen wrote:
>>
>>
>> >
>> >Nonetheless, it doesn't give true attitude information, and could
>> indicate negative pitch during a decent
>> >with the nose high, or zero pitch when hanging from the prop, etc.
>> >
>
>
>
________________________________________________________________________________
From: | N5SL <nfivesl(at)yahoo.com> |
Subject: | Re: Was antennas Now Fuse Block Location |
Lord Willing is good! How many of us feel that way?! Dave I plan to do a hook
with thin aluminum but I have to get all the wires installed first so I can fabricate
the hook out of the way.
I got the idea from Lance Gingell. His website has this photo:
http://wls1.lancegingell.com/largeplaneimages/DSC06143.jpg
It shows the hook. He used a different type of fuse block but you get the idea.
I used a marine fuse block with screw-type connectors since it would be swinging
down from time to time I wanted the wires to be really secure.
Take care,
Scott Laughlin
www.cooknwithgas.com
N5SL (slow learner)
David Henderson wrote:
Loved the pictures, great work! You let it swing down on demand but how is
it stowed? A magnet? A hook?
Dave Henderson RV-7 finishing kit
N925LW (Lord Willing)
---------------------------------
Click here to donate to the Hurricane Katrina relief effort.
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: VR for PM Alternator |
>
>
>I've just purchased a Jabiru 3300 powered OBAM sky skorcher project. 90%
>down, 90% to go.
>
>The Jab comes with a "solid state" voltage regulator. I understand that the
>PM Alternator (I think they call it a generator) was initially 3 phase but
>Jabiru changed to single phase because it was eating VRs. What's the
>difference?
A three-phase alternator has more volumetric efficiency than
two-phase . . . in plain-speak, a 3-phase machine will develop
more watts per cubic inch than a single-phase. Automotive, wound
field alternators have been 3-phase from day one.
It's to bad if Jabiru had to trade off the advantages of 3-phase
because nobody they knew was able to craft a suitable regulator.
Perhaps this would be a good design study . . . after I run the
load-dump, OV protection issues to ground on IR alternators.
>Since I have become a devotee of the Connection I have wired a Rotax 912UL
>powered sky skorcher with its Ducati ignition and VR with the predictable
>good results. I used architecture almost identical to Z-20, except for the
>LV warn system. It wasn't on the "small Rotax system" at the time.
>
>My question is this: Should I just go ahead and use the stock VR and add
>OVR/crowbar protection and LV warn as per Z-20 OR is there a VR out there
>for PM alternators with built-in OVP, LVW and temp compensation?
DC power generation with permanent magnet alternators is a special
case that requires a rectifier/regulator package capable of handling
full output current of the alternator. Wound field alternators like
those found on cars and most airplanes have the advantage of access
to control of field excitation to regulate voltage. It's a rare
regulator that has to grunt more than 3 amps in these cases. They're
completely separate breeds of cat.
>My battery, battery contactor, starter contactor and VR are all mounted
>close to each other on the firewall inside the engine compartment in a
>tightly cowled airplane. It was that way when I bought the project.
Z-20 with the lv warning would be my recommendation. The altenrator
you're presented with accommodates very few options.
Bob . . .
________________________________________________________________________________
From: | "Jim Baker" <jlbaker(at)telepath.com> |
Subject: | CK breaker life..... |
I'm not referring to cycles but age of the unit. I've had two breakers
on a '71 Bellanca Viking. One was a P&B 1 amp unit that supplied a
KLN90 GPS and the other, just last week, was a 5 amp ETA unit that
supplied the the autopilot (had an "event" that tripped the breaker
and found the cause to be a deformed contact on the bridge of the
24 pin Centronics connector Century Flight used for the control
head).
I suppose the ETA unit had a reason but the P&B unit just quit.
Wondering if I'm just lucky or are there age related lifetimes ( and
not related to the normal resistance buildups)....
Jim Baker
580.788.2779
'71 SV, 492TC
Elmore City, OK
________________________________________________________________________________
From: | Fiveonepw(at)aol.com |
Subject: | Re: Was antennas Now Fuse Block Location |
Here's my take on the same problem, perhaps some similar method could be
employed on yours- trays are secured with thumbscrews through the tray and into
platenuts on bottom of the sub-panel, which is about 6 inches behind the main
panel. Thumbscrews are retained in tray with small "keeper" washers (don't
recall exact name) that slip over the threads up against the back side of the
tray. First log entry shows initial tray fabrication and fitting:
http://websites.expercraft.com/n51pw/index.php?q=log_entry&log_id=5002
Click "Next Entry>>" at top of page to see right tray installed- left
thumbscrew is shown (small round brown plastic knob) and hole for other one is
on
right side of tray. Continue clicking next entry for subsequent views of panel
construction- there are a few more of the trays later on...
Mark Phillips - Columbia, TN
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: CK breaker life..... |
>
>I'm not referring to cycles but age of the unit. I've had two breakers
>on a '71 Bellanca Viking. One was a P&B 1 amp unit that supplied a
>KLN90 GPS and the other, just last week, was a 5 amp ETA unit that
>supplied the the autopilot (had an "event" that tripped the breaker
>and found the cause to be a deformed contact on the bridge of the
>24 pin Centronics connector Century Flight used for the control
>head).
>
>I suppose the ETA unit had a reason but the P&B unit just quit.
>Wondering if I'm just lucky or are there age related lifetimes ( and
>not related to the normal resistance buildups)....
Do you still have the failed breakers? I'd love to do
teardown inspections and see if we can deduce failure
modes. It's been my general observation that most
failures of electro-mechanical devices on light aircraft
die of old age. I think I've mentioned several times
here on the List that while study and understanding of
manufacturer's specifications is important, I cannot
recall a single instance where I've removed a failed
part wherein the part died due to lack of proper
respect for the part's ratings (i.e. overstressed
beyond manufacturer's published ratings).
Just last winter, I found a switch that went open
on the panel of a Beechjet. It was a $high$ Honneywell-
Microswitch product that was seldom moved. The airplane
was about 15 years old. In this particular case, the
contacts had corroded sufficiently to OPEN the circuit
on what was mechanically a brand new switch.
The tech I was working with wanted to go get a
replacement from the stockroom ($150 part/$150
labor to replace) but I asked him to hold off.
I connected a bench supply across the switch in
a constant current mode (3A I think) and set
it for 50v. After operating the switch a few
dozen times, contact resistance for the switch
was back down in the 4 milliohm range. The switch
will probably go another dozen years before it
needs attention. On the other hand, I don't KNOW
for sure if that was the original switch. Shucks,
there might have been a number of replacements
of that switch before I crossed paths with it.
This points out the risks of placing much stock
in second -> tenth-hand anecdotal data. "Anecdotal"
doesn't have to mean worthless or in error . . .
just suspect. When the data is first-hand,
one can have a fair confidence in the usefulness
of the data. As it passes through more individuals,
the need for healthy skepticism goes up.
Bob . . .
________________________________________________________________________________
From: | "Bruce Gray" <Bruce(at)glasair.org> |
Subject: | CK breaker life..... |
Sounds like a good reason to specify gold contacts.
Bruce
www.glasair.org
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L.
Nuckolls, III
Subject: Re: AeroElectric-List: CK breaker life.....
>
>I'm not referring to cycles but age of the unit. I've had two breakers
>on a '71 Bellanca Viking. One was a P&B 1 amp unit that supplied a
>KLN90 GPS and the other, just last week, was a 5 amp ETA unit that
>supplied the the autopilot (had an "event" that tripped the breaker
>and found the cause to be a deformed contact on the bridge of the
>24 pin Centronics connector Century Flight used for the control
>head).
>
>I suppose the ETA unit had a reason but the P&B unit just quit.
>Wondering if I'm just lucky or are there age related lifetimes ( and
>not related to the normal resistance buildups)....
Do you still have the failed breakers? I'd love to do
teardown inspections and see if we can deduce failure
modes. It's been my general observation that most
failures of electro-mechanical devices on light aircraft
die of old age. I think I've mentioned several times
here on the List that while study and understanding of
manufacturer's specifications is important, I cannot
recall a single instance where I've removed a failed
part wherein the part died due to lack of proper
respect for the part's ratings (i.e. overstressed
beyond manufacturer's published ratings).
Just last winter, I found a switch that went open
on the panel of a Beechjet. It was a $high$ Honneywell-
Microswitch product that was seldom moved. The airplane
was about 15 years old. In this particular case, the
contacts had corroded sufficiently to OPEN the circuit
on what was mechanically a brand new switch.
The tech I was working with wanted to go get a
replacement from the stockroom ($150 part/$150
labor to replace) but I asked him to hold off.
I connected a bench supply across the switch in
a constant current mode (3A I think) and set
it for 50v. After operating the switch a few
dozen times, contact resistance for the switch
was back down in the 4 milliohm range. The switch
will probably go another dozen years before it
needs attention. On the other hand, I don't KNOW
for sure if that was the original switch. Shucks,
there might have been a number of replacements
of that switch before I crossed paths with it.
This points out the risks of placing much stock
in second -> tenth-hand anecdotal data. "Anecdotal"
doesn't have to mean worthless or in error . . .
just suspect. When the data is first-hand,
one can have a fair confidence in the usefulness
of the data. As it passes through more individuals,
the need for healthy skepticism goes up.
Bob . . .
________________________________________________________________________________
Subject: | Re: Cage horizon when powering up ? |
>>To cage or not to cage before powering up our electric gyro ?
>>Do you happen to have any more information ?
>>
>>
>
> I've talk to two ol' instrument mechanics with square
> glasses who said about the same thing. Manufacturers
> of gyros have published various admonitions for use of their
> products to avoid unnecessary stresses and/or avoid obvious
> hazards to damage. There's no consistent thread among them
> except that the same items keep popping up from time to time.
>
> They were aware of no gyro products that would exhibit
> a demonstrably longer service life in a non-aerobatic
> aircraft based on caging habits of the pilot. Some gyros
> would erect faster if uncaged after power up but even that
> "benefit" was marginally useful . . . there were no properly
> operating gyros that wouldn't be fully stood up by the time
> the airplane was ready for takeoff no matter how it was
> oriented before power up. I'll keep nosing around.
>
>
Bob,
Thank you once again for your help.
Regards,
Gilles Thesee
Grenoble, France
http://contrails.free.fr
________________________________________________________________________________
Subject: | Why are wire strands tinned ? |
Hi Bob and all,
Another question about wires. I know it has been addressed in the past,
but couldn't remember.
Are the strands tinned for solderability ? Or corrosion resistance, or
both ?
Thanks in advance,
Regards,
Gilles Thesee
Grenoble, France
http://contrails.free.fr
________________________________________________________________________________
From: | "Ed Anderson" <eanderson(at)carolina.rr.com> |
Subject: | Re: Why are wire strands tinned ? |
I believe it was done primarily for Corrosion resistance. In older
automobiles it was not unusual to start to have electrical problems after
about 10 years or so due to the oxygen penetrating the plastic insulation
and causing oxidation of the copper changing the conducting properties of
the wire. Of course it does help the solderability of the wire as well.
Your name reminded me - I have an ancestor named Gilles Bertrand from
L'eveche De St Brieuc, Bretagne France. Hope to visit someday.
Ed Anderson
RV-6A N494BW Rotary Powered
Matthews, NC
eanderson(at)carolina.rr.com
----- Original Message -----
From: "Gilles Thesee" <Gilles.Thesee@ac-grenoble.fr>
Subject: AeroElectric-List: Why are wire strands tinned ?
> <Gilles.Thesee@ac-grenoble.fr>
>
> Hi Bob and all,
>
> Another question about wires. I know it has been addressed in the past,
> but couldn't remember.
> Are the strands tinned for solderability ? Or corrosion resistance, or
> both ?
>
> Thanks in advance,
> Regards,
>
> Gilles Thesee
> Grenoble, France
> http://contrails.free.fr
>
>
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | CK breaker life..... |
>
>Sounds like a good reason to specify gold contacts.
>
>Bruce
>www.glasair.org
Maybe. This particular switch was tasked with carrying
a couple of amps . . . on occasion.
For those interested in studying contact science and switch
design vs. application, I'll recommend these two documents from
one of the premier suppliers of switches. See:
http://content.honeywell.com/sensing/prodinfo/basicswitches/technical/010172.pdf
http://content.honeywell.com/sensing/prodinfo/basicswitches/technical/001008_3.pdf
I used a number of jewels of simple-ideas from these documents
while running down a sticking relay problem a few years ago and
for some open-contact problems some time later. These are unusually
enlightening papers.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: Why are wire strands tinned ? |
> Are the strands tinned for solderability ? Or corrosion resistance, or
> both ?
>
>
>I believe it was done primarily for Corrosion resistance. In older
>automobiles it was not unusual to start to have electrical problems after
>about 10 years or so due to the oxygen penetrating the plastic insulation
>and causing oxidation of the copper changing the conducting properties of
>the wire. Of course it does help the solderability of the wire as well.
Ed is right, it was mostly for corrosion resistance but solderability
gets a direct benefit from corrosion free or lightly corroded surfaces.
Bob . . .
________________________________________________________________________________
From: | "Eric M. Jones" <emjones(at)charter.net> |
Subject: | Re: Why are wire strands tinned ? |
There is not much reason to plate the copper wire. I have seen cables where
some wire was plated only for identification (apparently), while audio buffs
claim that copper oxide causes diode effects and thus all audio wire should
be plated. Of course, all real audiophiles are insane.
Marine types say it is to prevent corrosion. So they have tinned copper
cables yet put copper bottoms on their boats. Copper and brass are good in
saltwater.
One could surmise that some high-frequency effects are improved because of
skin effect.
There are local old houses hereabouts wired in IRON wire.
My guess is it's just floccinaucinihilipilification.
By the way I will gladly sample my Super-4-CCA to interested parties. Email
me off list.
Regards,
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge MA 01550-2705
(508) 764-2072
"The problem with the world is that only the intelligent people want to be
smarter, and only the good people want to improve."
- Eolake Stobblehouse
________________________________________________________________________________
Subject: | Re: Why are wire strands tinned ? |
Ed Anderson a crit :
>
>I believe it was done primarily for Corrosion resistance. In older
>automobiles it was not unusual to start to have electrical problems after
>about 10 years or so due to the oxygen penetrating the plastic insulation
>and causing oxidation of the copper changing the conducting properties of
>the wire. Of course it does help the solderability of the wire as well.
>
>Your name reminded me - I have an ancestor named Gilles Bertrand from
>L'eveche De St Brieuc, Bretagne France. Hope to visit someday.
>
>
Thanks to Bob, Ed, Eric (in alphabetic order ;-) for your answers.
Ed, the Bretagne is a fascinating land. It is the westernmost part of
France, forests, fields and moors beaten by the westerlies, ragged rocky
coasts and menhirs erected by people long forgotten.
Everywhere in Bretagne you'll feel the presence of the fairies and
magicians of past centuries, and the sea is ever present.
And yet in summer it is the warmest of all places.
Well, would you believe I love this land ?
Best regards,
Amicalement,
Gilles
http://contrails.free.fr
________________________________________________________________________________
From: | luckymacy(at)comcast.net (lucky) |
Subject: | capacitor and music jack help needed |
1.53 RCVD_NUMERIC_HELO Received: contains an IP address used for HELO
I have a XCOM 760 radio and I just checked into their website for the first time
in a long time and leared that they now insist all their radios must be fitted
with a 22,000uF/25VDC electrolytic capacitor, 85C. But I can't find that
exact match using google, e-bay or any of the couple of electronic web site catalogs
I bookmarked.
Can anyone help?
While I'm at it, I never did run across a mono music jack that I'm supposed to
find and purchase for their premade harness. The harness has two tinned bare
wires that are "Y"d on the jack end and all the 1/8th inch mono jacks in the local
electronic stores seem to have 3 or 4 solder lugs on them. So I didn't want
to experiment and ruin the radio or an ipod. Does anyone have an idea on
what to do about that as well? Any XCOM 760 users out there?
thanks,
Lucky
I have a XCOM 760 radio and I just checked into their website for the first time
in a long time and leared that they now insist all their radios must be fitted
with a 22,000uF/25VDC electrolytic capacitor, 85C. But I can't find that exact
match using google, e-bay or any of the couple of electronic web site catalogs
I bookmarked.
Can anyone help?
While I'm at it, I never did run across a mono music jack thatI'm supposed to find
and purchasefor their premade harness. The harness has two tinned bare wires
that are "Y"d on thejack endand all the 1/8th inch mono jacks in the local
electronic stores seem to have 3 or 4 solder lugs on them. So I didn't want to
experiment and ruinthe radio or an ipod. Does anyone have an idea on what to
do about that as well? Any XCOM 760 users out there?
thanks,
Lucky
________________________________________________________________________________
From: | "bob noffs" <icubob(at)newnorth.net> |
hi all, thanks to all for replys on the antenna and individual fuse holders. the
fuse holders are definitely out of the picture. they definitely leave a lot
of wire unprotected. i am leaning toward a fuse box with some sort of cover.
i am not sure what i will do about the antenna. guess i will sit on that one
for a while.
bob noffs
________________________________________________________________________________
Subject: | Re: capacitor and music jack help needed |
From: | "Matt Prather" <mprather(at)spro.net> |
Hello Lucky,
See below.
>
> I have a XCOM 760 radio and I just checked into their website for the
> first time in a long time and leared that they now insist all their
> radios must be fitted with a 22,000uF/25VDC electrolytic capacitor,
> 85C. But I can't find that exact match using google, e-bay or any of
> the couple of electronic web site catalogs I bookmarked.
>
It would be perfectly safe to substitute a cap with a higher voltage
rating. Googling around, I found several different caps in the 30-50VDC
rating range. To be honest with you though, this seems like ridulously
large cap for a 5W radio. These caps are cheap and plentiful however, so
there's no harm in doing as the manufacture specifies. At the same time,
I'd be tempted to install and test the radio without the cap (there's no
risk to the radio). If you have a performance problem (noise), then
consider adding the cap.
snip
> thanks,
> Lucky
>
Regards,
Matt-
________________________________________________________________________________
From: | "Rodney Dunham" <rdunhamtn(at)hotmail.com> |
Subject: | capacitor and music jack help needed |
Lucky,
Matt is right, you may not need a capacitor at all IF you don't have a noise
problem. BUT you may not recognize your noise problem! It might not be noise
in your ear. It might be a GPS that loses satellite lock or some other
equally esoteric and unrecognizable anomaly in your avionics! Also, PM
alternators like it there for their own health. 22,000 mF is arrived at
using a "rule-of-thumb" conversion which depends on the ALT output (Amps) to
be filtered, not the consumer's amp rating. Mine filters an 18 Amp PM
alternator. Rotax calls for the same 22K mF capacitor. I used a 47K mF
capacitor included in an overvolt protection kit purchased from B&C
Specialty Products online. While you're at it, do your avionics another big
favor and install Bob's OVP system available from the same site,
bandcspecialty.com.
That's the short answer. For the long answer keep reading.
The 22,000 microFarad capacitor is used to filter the ALT output.The ALT
produces AC current . The waveform of the AC current resembles a sine wave.
Imagine a single-line dollar sign tipped over on its side. One half of the
sine wave above 0 volts the other below it, ie. 0 to +14 back to 0 to -14
back to 0 and so on. This is dutifully converted to DC current by the
rectifier by chopping off the bottom half of the sine waves. The result is a
bunch of overlapping top halves and is very close to
14VDC current except for a "ripple" of voltage varying from, say, +13 to +14
volts.* This current is passed to your power distribution bus and is
available to the various electric "consumers" such as the BAT and your very
nice XCOM 760. If you didn't have any avionionics, you'd be done wiring.
The problem with this unfiltered energy is that the ripple, that little AC
current from +13 to +14*, causes a constantly expanding and collapsing
magnetic field which in turn causes a matching AC current to be established
in any unshielded wires within its sphere of influence, ie... your XCOM. A
small amplitude, say 1/2 volt AC current is now supermiposed onto the 14VDC
supply current from your fuse block to your radio. This causes "noise" in
your set, your headphones, your GPS, etc... and you're NOT done wiring.
Sooo.... The first step is to connect the VR output to the aforementioned
22K mF capacitor on its way to the battery and power distribution bus. The
capacitor attenuates and slightly delays the ripple. In other words it makes
it smaller. Smaller (less amplitude) ripple equals weaker magnetic field
equals smaller ripple voltage induced in your XCOM. Notice, however, that it
does NOT eliminate the ripple. There is no noise-free power (save your BAT
alone) but it does make things "quieter", so to speak. One caveat... The
capacitor can be bigger than the one recommended. See above. Mine is 47K mF
and the power leads from the VR go to it on the + terminal then from the +
terminal to the OV relay then to the starter contactor hot side and on to
the battery. This produces the "cleanest" DC power one can produce from such
a system. I think! :o)
Next.... Shield the power supply wires from the fuse block to the "load" ie,
your XCOM and any other wires subject to RFI such as phones, GPS, etc...
Also note, a linear ground bus system as designed by our fearless leader
(and available at B&C Specialty Products**) will add to your electrical
hygeine by preventing the legendary ground loop!
Rodney in Tennessee
* Numbers not to be considered actual, real life, scientifically produced,
ie valid numbers. Just pulled 'em out of my posterior for the purpose of
illustration.
**I do not work for or receive compensation from B&C in any way. I just love
their stuff because it works, it's relatively inexpensive and I can
understand it!
________________________________________________________________________________
From: | <bakerocb(at)cox.net> |
<< hi all, i have bobs book but i was looking for a detailed ''how to''
set of directions
for building a comm antenna. bobs drawings leave too much to my
imagination
and i end up with more questions than when i started . i am not at all
familiar
with electronics. that i can even send this e mail is a miracle. anything
on
a web site anyone knows of? from bobs book it seems that the antenna is
very
basic stuff but i need more help shopping for parts for one
thing.....skip..... bob noffs>>
10/02/2005
Hello Bob Noffs, Bob Nuckolls' advice to buy a ready made antenna is very
sound. But it is possible to roll your own inexpensively and quickly.
Go to this web site for specifices. http://www.rst-engr.com/
Many of us have good working copper tape nav and comm antennas inside our
composite airplanes.
OC
________________________________________________________________________________
From: | "Dan Morrow" <DanFM01(at)butter.toast.net> |
Subject: | Re: Why are wire strands tinned ? |
Having owned a sailboat used in salt water for many years, I can comment
on this. Copper sheathing was used on ships in the 18th and 19th centuries
to control barnacles and other growth. The sheathing was sacrificial in
nature and could be replaced. I am not aware of copper sheathing being used
on boats or ships in the last century. The modern technique is to use
antifouling paints that contain materials poisonous to marine life. Copper
and tin compounds were the most common before the environmentalists started
banning them.
Salt water is death to most unprotected metals. Stainless steel and bronze
are the only metals that can be used topside under salt water spray.
Aluminum and other metals can only be used if protected by paint or
anodyzing. Brass can be used in the cabin. It needs to be laquered or
otherwise protected if it is to look good.
My sailboat, which was built in 1974, was wired with plain copper wires.
I have had problems with corrosion of the wire. The salt air penetrates
anywhere there is a break in the insulation and eats up the wire.
An airplane is typically in a much more benign environment unless it is
based near salt water. Nonetheless, I think tinned wire is a real good
idea.
----- Original Message -----
From: "Eric M. Jones" <emjones(at)charter.net>
Subject: AeroElectric-List: Re: Why are wire strands tinned ?
>
>
> There is not much reason to plate the copper wire. I have seen cables
> where
> some wire was plated only for identification (apparently), while audio
> buffs
> claim that copper oxide causes diode effects and thus all audio wire
> should
> be plated. Of course, all real audiophiles are insane.
>
> Marine types say it is to prevent corrosion. So they have tinned copper
> cables yet put copper bottoms on their boats. Copper and brass are good in
> saltwater.
>
> One could surmise that some high-frequency effects are improved because of
> skin effect.
>
> There are local old houses hereabouts wired in IRON wire.
>
> My guess is it's just floccinaucinihilipilification.
>
> By the way I will gladly sample my Super-4-CCA to interested parties.
> Email
> me off list.
>
> Regards,
> Eric M. Jones
> www.PerihelionDesign.com
> 113 Brentwood Drive
> Southbridge MA 01550-2705
> (508) 764-2072
>
> "The problem with the world is that only the intelligent people want to be
> smarter, and only the good people want to improve."
> - Eolake Stobblehouse
>
>
> --
>
>
________________________________________________________________________________
From: | "Eric M. Jones" <emjones(at)charter.net> |
Subject: | Re: capacitor and music jack help needed |
>I have a XCOM 760 radio and I just checked into their website for the first
>time
>in a long time and leared that they now insist all their radios must be
>fitted
>with a 22,000uF/25VDC electrolytic capacitor, 85C. But I can't find that
>exact match using google, e-bay or any of the couple of electronic web site
>catalogs
>I bookmarked.
Hi Lucky,
The general rule in capacitors is that you can always use a higher voltage
one; a bigger one unless it's a timing circuit. But as they say the devil is
in the details.
My computer motherboard had a dozen failed electrolytics (of the TRILLIONS
[YIKES!] made by a dozen Oriental companies for Abit, Asus, Aopen, Dell, HP,
etc.,etc.,etc.; this may have been one of the greatest engineering disasters
of the decade, and there is an interesting tale as to how it happened
involving stolen R&D secrets that didn't really work out. There are some
truly monster lawsuits in the works. But I digress....). I replaced most of
my motherboard's electrolytic capacitors "E-caps"...but this is not for the
faint-hearted.
I mention this as general information to spur thinking on using E-caps when
you can avoid it. But my opinion of using a 22,000 uF/25V cap to eliminate
noise from the B+ supply to the XCOM radio or any other system is that this
is a very poor way to do things. The capacitor itself is an inch in diameter
and two inches long and weighs over three ounces. At 14V it contains a
couple joules of energy. Most E-caps are not rated for altitude cycling and
temperature cycling unless you buy the expensive military versions.
Hmmm......
A far better technique than using a single fat electrolytic cap is to use an
in-line inductor and a capacitor. Certainly this is within the ability of
XCOM or anyone else with some knowledge of the subject. It goes without
saying...so I will say it...that several parts should be added for the thing
to work well:
1-A 0.1 uF ceramic cap across the big capacitor to stop high-frequency brush
noise.
2-An 18 volt zener across the capacitor to protect it from fast HV
transients.
3-Maybe a solid state resettable fuse in case the cap shorts.
4-Note that XCOM has the cap before the fuse. This needs some thinking.
Bob N. has a good paper on this:
http://www.aeroelectric.com/articles/filter/RS_Noise_Filters.pdf , It could
be expanded to remedy this XCOM patch-job and provide a number of user
friendly filters.
A really robust and useful filter that is hardly ever used is an LM317
voltage regulator (or better yet some of its newer sisters). These voltage
regulators can do a much better filtering job than a pound of capacitor and
inductor, especially at audio frequencies.
Regards,
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge MA 01550-2705
(508) 764-2072
"Every act of conscious learning requires the willingness to suffer an
injury to one's self-esteem...."
-Thomas Szasz
________________________________________________________________________________
From: | "Eric M. Jones" <emjones(at)charter.net> |
Subject: | Re: capacitor and music jack help needed |
>I have a XCOM 760 radio and I just checked into their website for the first
>time
>in a long time and leared that they now insist all their radios must be
>fitted
>with a 22,000uF/25VDC electrolytic capacitor, 85C. But I can't find that
>exact match using google, e-bay or any of the couple of electronic web site
>catalogs
>I bookmarked.
Hi Lucky,
The general rule in capacitors is that you can always use a higher voltage
one; a bigger one unless it's a timing circuit. But as they say the devil is
in the details.
My computer motherboard had a dozen failed electrolytics (of the TRILLIONS
[YIKES!] made by a dozen Oriental companies for Abit, Asus, Aopen, Dell, HP,
etc.,etc.,etc.; this may have been one of the greatest engineering disasters
of the decade, and there is an interesting tale as to how it happened
involving stolen R&D secrets that didn't really work out. There are some
truly monster lawsuits in the works. But I digress....). I replaced most of
my motherboard's electrolytic capacitors "E-caps"...but this is not for the
faint-hearted.
I mention this as general information to spur thinking on using E-caps when
you can avoid it. But my opinion of using a 22,000 uF/25V cap to eliminate
noise from the B+ supply to the XCOM radio or any other system is that this
is a very poor way to do things. The capacitor itself is an inch in diameter
and two inches long and weighs over three ounces. At 14V it contains a
couple joules of energy. Most E-caps are not rated for altitude cycling and
temperature cycling unless you buy the expensive military versions.
Hmmm......
A far better technique than using a single fat electrolytic cap is to use an
in-line inductor and a capacitor. Certainly this is within the ability of
XCOM or anyone else with some knowledge of the subject. It goes without
saying...so I will say it...that several parts should be added for the thing
to work well:
1-A 0.1 uF ceramic cap across the big capacitor to stop high-frequency brush
noise.
2-An 18 volt zener across the capacitor to protect it from fast HV
transients.
3-Maybe a solid state resettable fuse in case the cap shorts.
4-Note that XCOM has the cap before the fuse. This needs some thinking.
Bob N. has a good paper on this:
http://www.aeroelectric.com/articles/filter/RS_Noise_Filters.pdf , It could
be expanded to remedy this XCOM patch-job and provide a number of user
friendly filters.
A really robust and useful filter that is hardly ever used is an LM317
voltage regulator (or better yet some of its newer sisters). These voltage
regulators can do a much better filtering job than a pound of capacitor and
inductor, especially at audio frequencies.
Regards,
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge MA 01550-2705
(508) 764-2072
"Every act of conscious learning requires the willingness to suffer an
injury to one's self-esteem...."
-Thomas Szasz
________________________________________________________________________________
From: | "Eric M. Jones" <emjones(at)charter.net> |
Subject: | Re: capacitor and music jack help needed |
>I have a XCOM 760 radio and I just checked into their website for the first
>time
>in a long time and leared that they now insist all their radios must be
>fitted
>with a 22,000uF/25VDC electrolytic capacitor, 85C. But I can't find that
>exact match using google, e-bay or any of the couple of electronic web site
>catalogs
>I bookmarked.
Hi Lucky,
The general rule in capacitors is that you can always use a higher voltage
one; a bigger one unless it's a timing circuit. But as they say the devil is
in the details.
My computer motherboard had a dozen failed electrolytics (of the TRILLIONS
[YIKES!] made by a dozen Oriental companies for Abit, Asus, Aopen, Dell, HP,
etc.,etc.,etc.; this may have been one of the greatest engineering disasters
of the decade, and there is an interesting tale as to how it happened
involving stolen R&D secrets that didn't really work out. There are some
truly monster lawsuits in the works. But I digress....). I replaced most of
my motherboard's electrolytic capacitors "E-caps"...but this is not for the
faint-hearted.
I mention this as general information to spur thinking on using E-caps when
you can avoid it. But my opinion of using a 22,000 uF/25V cap to eliminate
noise from the B+ supply to the XCOM radio or any other system is that this
is a very poor way to do things. The capacitor itself is an inch in diameter
and two inches long and weighs over three ounces. At 14V it contains a
couple joules of energy. Most E-caps are not rated for altitude cycling and
temperature cycling unless you buy the expensive military versions.
Hmmm......
A far better technique than using a single fat electrolytic cap is to use an
in-line inductor and a capacitor. Certainly this is within the ability of
XCOM or anyone else with some knowledge of the subject. It goes without
saying...so I will say it...that several parts should be added for the thing
to work well:
1-A 0.1 uF ceramic cap across the big capacitor to stop high-frequency brush
noise.
2-An 18 volt zener across the capacitor to protect it from fast HV
transients.
3-Maybe a solid state resettable fuse in case the cap shorts.
4-Note that XCOM has the cap before the fuse. This needs some thinking.
Bob N. has a good paper on this:
http://www.aeroelectric.com/articles/filter/RS_Noise_Filters.pdf , It could
be expanded to remedy this XCOM patch-job and provide a number of user
friendly filters.
A really robust and useful filter that is hardly ever used is an LM317
voltage regulator (or better yet some of its newer sisters). These voltage
regulators can do a much better filtering job than a pound of capacitor and
inductor, especially at audio frequencies.
Regards,
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge MA 01550-2705
(508) 764-2072
"Every act of conscious learning requires the willingness to suffer an
injury to one's self-esteem...."
-Thomas Szasz
________________________________________________________________________________
Subject: | capacitor and music jack help needed |
From: | "Matt Prather" <mprather(at)spro.net> |
Hi Rodney,
I generally agree with what you have said here. A couple of comments
though. Big caps on the input of a device are generally there to provide
better performance against transient demand. That is, when a consumer
needs a big burst of electrons (say it's a comm radio and you push the
transmit button), the extra capacitance helps support the bus voltage by
being a local reservoir. Additionally, this reservoir effect means that
the transient load causes less noise elsewhere in the system.
Conversely, to reduce the effects of ripple on the output of the
alternator, the big cap should be placed at the regulator (as you
suggest). A capacitor only is an effective filter when it's placed close
to the device causing the bus transient (be it load or source). The
further from the offending device the cap is wired, the more R and L
effects reduce it's ability.
So, I wonder which reason the XCOM needs the cap. Is it that it needs
less ripple on the input, or less sag when you push the transmit button,
or is it that the XCOM is a noisy resident on a power buss. If it's a
noisy consumer, place the cap as close to the radio as possible (so that
it doesn't disturb the GPS or other devices). If it's sensitive to
ripple, then place the big cap close the output of the alternator.
Regards,
Matt-
>
>
> Lucky,
>
> Matt is right, you may not need a capacitor at all IF you don't have a
> noise problem. BUT you may not recognize your noise problem! It might
> not be noise in your ear. It might be a GPS that loses satellite lock
> or some other equally esoteric and unrecognizable anomaly in your
> avionics! Also, PM alternators like it there for their own health.
> 22,000 mF is arrived at using a "rule-of-thumb" conversion which
> depends on the ALT output (Amps) to be filtered, not the consumer's amp
> rating. Mine filters an 18 Amp PM alternator. Rotax calls for the same
> 22K mF capacitor. I used a 47K mF capacitor included in an overvolt
> protection kit purchased from B&C Specialty Products online. While
> you're at it, do your avionics another big favor and install Bob's OVP
> system available from the same site,
> bandcspecialty.com.
>
> That's the short answer. For the long answer keep reading.
>
> The 22,000 microFarad capacitor is used to filter the ALT output.The ALT
> produces AC current . The waveform of the AC current resembles a sine
> wave. Imagine a single-line dollar sign tipped over on its side. One
> half of the sine wave above 0 volts the other below it, ie. 0 to +14
> back to 0 to -14 back to 0 and so on. This is dutifully converted to DC
> current by the rectifier by chopping off the bottom half of the sine
> waves. The result is a bunch of overlapping top halves and is very
> close to
> 14VDC current except for a "ripple" of voltage varying from, say, +13 to
> +14 volts.* This current is passed to your power distribution bus and
> is available to the various electric "consumers" such as the BAT and
> your very nice XCOM 760. If you didn't have any avionionics, you'd be
> done wiring.
>
> The problem with this unfiltered energy is that the ripple, that little
> AC current from +13 to +14*, causes a constantly expanding and
> collapsing magnetic field which in turn causes a matching AC current to
> be established in any unshielded wires within its sphere of influence,
> ie... your XCOM. A small amplitude, say 1/2 volt AC current is now
> supermiposed onto the 14VDC supply current from your fuse block to your
> radio. This causes "noise" in your set, your headphones, your GPS,
> etc... and you're NOT done wiring.
>
> Sooo.... The first step is to connect the VR output to the
> aforementioned 22K mF capacitor on its way to the battery and power
> distribution bus. The capacitor attenuates and slightly delays the
> ripple. In other words it makes it smaller. Smaller (less amplitude)
> ripple equals weaker magnetic field equals smaller ripple voltage
> induced in your XCOM. Notice, however, that it does NOT eliminate the
> ripple. There is no noise-free power (save your BAT alone) but it does
> make things "quieter", so to speak. One caveat... The capacitor can be
> bigger than the one recommended. See above. Mine is 47K mF and the
> power leads from the VR go to it on the + terminal then from the +
> terminal to the OV relay then to the starter contactor hot side and on
> to the battery. This produces the "cleanest" DC power one can produce
> from such a system. I think! :o)
>
> Next.... Shield the power supply wires from the fuse block to the "load"
> ie, your XCOM and any other wires subject to RFI such as phones, GPS,
> etc... Also note, a linear ground bus system as designed by our
> fearless leader (and available at B&C Specialty Products**) will add to
> your electrical hygeine by preventing the legendary ground loop!
>
> Rodney in Tennessee
>
> * Numbers not to be considered actual, real life, scientifically
> produced, ie valid numbers. Just pulled 'em out of my posterior for the
> purpose of illustration.
> **I do not work for or receive compensation from B&C in any way. I just
> love their stuff because it works, it's relatively inexpensive and I
> can understand it!
>
>
________________________________________________________________________________
Subject: | Re: capacitor and music jack help needed |
From: | "Matt Prather" <mprather(at)spro.net> |
The thing that is slightly frustrating about this whole discussion is that
when you buy the XCOM (or whatever else), presumably you are buying a comm
transceiver that is designed to be installed in an aircraft. And that it
will be wired into the aircraft power buss. Why the heck wasn't the radio
designed to perform correctly in that environment (without adding
additional "stuff")??
Eric, I agree that a LM317 or something more modern is a great way to
provide clean power to a device, but the XCOM's go for something like $1k.
I'm sure it has a regulated power supply built in...
Matt-
>
>
>
>>I have a XCOM 760 radio and I just checked into their website for the
>> first time
>>in a long time and leared that they now insist all their radios must be
>> fitted
>>with a 22,000uF/25VDC electrolytic capacitor, 85C. But I can't find
>> that exact match using google, e-bay or any of the couple of electronic
>> web site catalogs
>>I bookmarked.
>
> Hi Lucky,
>
> The general rule in capacitors is that you can always use a higher
> voltage one; a bigger one unless it's a timing circuit. But as they say
> the devil is in the details.
>
> My computer motherboard had a dozen failed electrolytics (of the
> TRILLIONS [YIKES!] made by a dozen Oriental companies for Abit, Asus,
> Aopen, Dell, HP, etc.,etc.,etc.; this may have been one of the greatest
> engineering disasters of the decade, and there is an interesting tale
> as to how it happened involving stolen R&D secrets that didn't really
> work out. There are some truly monster lawsuits in the works. But I
> digress....). I replaced most of my motherboard's electrolytic
> capacitors "E-caps"...but this is not for the faint-hearted.
>
> I mention this as general information to spur thinking on using E-caps
> when you can avoid it. But my opinion of using a 22,000 uF/25V cap to
> eliminate noise from the B+ supply to the XCOM radio or any other
> system is that this is a very poor way to do things. The capacitor
> itself is an inch in diameter and two inches long and weighs over three
> ounces. At 14V it contains a couple joules of energy. Most E-caps are
> not rated for altitude cycling and temperature cycling unless you buy
> the expensive military versions. Hmmm......
>
> A far better technique than using a single fat electrolytic cap is to
> use an in-line inductor and a capacitor. Certainly this is within the
> ability of XCOM or anyone else with some knowledge of the subject. It
> goes without saying...so I will say it...that several parts should be
> added for the thing to work well:
>
> 1-A 0.1 uF ceramic cap across the big capacitor to stop high-frequency
> brush noise.
> 2-An 18 volt zener across the capacitor to protect it from fast HV
> transients.
> 3-Maybe a solid state resettable fuse in case the cap shorts.
> 4-Note that XCOM has the cap before the fuse. This needs some thinking.
>
> Bob N. has a good paper on this:
> http://www.aeroelectric.com/articles/filter/RS_Noise_Filters.pdf , It
> could be expanded to remedy this XCOM patch-job and provide a number of
> user friendly filters.
>
> A really robust and useful filter that is hardly ever used is an LM317
> voltage regulator (or better yet some of its newer sisters). These
> voltage regulators can do a much better filtering job than a pound of
> capacitor and inductor, especially at audio frequencies.
>
> Regards,
> Eric M. Jones
> www.PerihelionDesign.com
> 113 Brentwood Drive
> Southbridge MA 01550-2705
> (508) 764-2072
>
> "Every act of conscious learning requires the willingness to suffer an
> injury to one's self-esteem...."
> -Thomas Szasz
>
>
________________________________________________________________________________
From: | "Europa (Alfred Buess)" <ykibuess(at)bluewin.ch> |
Subject: | Re: Was antennas Now Fuse Block Location |
Hi Bob,
Have a look at this solution (kit: Europa XS)
http://www.europaowners.org/Fuse-panel-in-picnic-tray
Regards,
Alfred
Alfred Buess
Laenggasse 81, CH-3052 Zollikofen, Switzerland
Tel.: +41 (0)31 911 63 32, Fax: +41 (0)31 911 56 32
E-Mail: ykibuess(at)bluewin.ch
Europa XS #097, Monowheel, Foam shortwing, Rotax 912S, Airmaster 332 CS
bob noffs wrote:
hi all,
i was just looking and thinking about the best place for my fuse panel.
---------------------------------
Click here to donate to the Hurricane Katrina relief effort.
________________________________________________________________________________
From: | luckymacy(at)comcast.net (lucky) |
Subject: | Re: capacitor and music jack help needed |
What if I just got something like the one at
http://www.sphere.bc.ca/test/inductors.html
Fair Rite Snap-It RFI Ferrite Suppressors....Fits wires/bundles up to 10mm/0.390
inch in diameter, easily opens and snaps shut, fantastic for quenching EMI/RFI
emissions from already existing equipment, power cords, cables, and connections.
Type 0443167251, approx. 225 ohms impedance at 100Mhz, very efficient and
inexpensive emission solution.
Seems like it would be easy to install and remove if it didn't work.
-------------- Original message --------------
>
> The thing that is slightly frustrating about this whole discussion is that
> when you buy the XCOM (or whatever else), presumably you are buying a comm
> transceiver that is designed to be installed in an aircraft. And that it
> will be wired into the aircraft power buss. Why the heck wasn't the radio
> designed to perform correctly in that environment (without adding
> additional "stuff")??
>
> Eric, I agree that a LM317 or something more modern is a great way to
> provide clean power to a device, but the XCOM's go for something like $1k.
> I'm sure it has a regulated power supply built in...
>
>
> Matt-
>
> >
> >
> >
> >>I have a XCOM 760 radio and I just checked into their website for the
> >> first time
> >>in a long time and leared that they now insist all their radios must be
> >> fitted
> >>with a 22,000uF/25VDC electrolytic capacitor, 85C. But I can't find
> >> that exact match using google, e-bay or any of the couple of electronic
> >> web site catalogs
> >>I bookmarked.
> >
> > Hi Lucky,
> >
> > The general rule in capacitors is that you can always use a higher
> > voltage one; a bigger one unless it's a timing circuit. But as they say
> > the devil is in the details.
> >
> > My computer motherboard had a dozen failed electrolytics (of the
> > TRILLIONS [YIKES!] made by a dozen Oriental companies for Abit, Asus,
> > Aopen, Dell, HP, etc.,etc.,etc.; this may have been one of the greatest
> > engineering disasters of the decade, and there is an interesting tale
> > as to how it happened involving stolen R&D secrets that didn't really
> > work out. There are some truly monster lawsuits in the works. But I
> > digress....). I replaced most of my motherboard's electrolytic
> > capacitors "E-caps"...but this is not for the faint-hearted.
> >
> > I mention this as general information to spur thinking on using E-caps
> > when you can avoid it. But my opinion of using a 22,000 uF/25V cap to
> > eliminate noise from the B+ supply to the XCOM radio or any other
> > system is that this is a very poor way to do things. The capacitor
> > itself is an inch in diameter and two inches long and weighs over three
> > ounces. At 14V it contains a couple joules of energy. Most E-caps are
> > not rated for altitude cycling and temperature cycling unless you buy
> > the expensive military versions. Hmmm......
> >
> > A far better technique than using a single fat electrolytic cap is to
> > use an in-line inductor and a capacitor. Certainly this is within the
> > ability of XCOM or anyone else with some knowledge of the subject. It
> > goes without saying...so I will say it...that several parts should be
> > added for the thing to work well:
> >
> > 1-A 0.1 uF ceramic cap across the big capacitor to stop high-frequency
> > brush noise.
> > 2-An 18 volt zener across the capacitor to protect it from fast HV
> > transients.
> > 3-Maybe a solid state resettable fuse in case the cap shorts.
> > 4-Note that XCOM has the cap before the fuse. This needs some thinking.
> >
> > Bob N. has a good paper on this:
> > http://www.aeroelectric.com/articles/filter/RS_Noise_Filters.pdf , It
> > could be expanded to remedy this XCOM patch-job and provide a number of
> > user friendly filters.
> >
> > A really robust and useful filter that is hardly ever used is an LM317
> > voltage regulator (or better yet some of its newer sisters). These
> > voltage regulators can do a much better filtering job than a pound of
> > capacitor and inductor, especially at audio frequencies.
> >
> > Regards,
> > Eric M. Jones
> > www.PerihelionDesign.com
> > 113 Brentwood Drive
> > Southbridge MA 01550-2705
> > (508) 764-2072
> >
> > "Every act of conscious learning requires the willingness to suffer an
> > injury to one's self-esteem...."
> > -Thomas Szasz
> >
> >
>
>
>
>
>
>
What if I just got something like the one at
http://www.sphere.bc.ca/test/inductors.html
Fair Rite Snap-It RFI Ferrite Suppressors....Fits wires/bundles up to 10mm/0.390
inch in diameter, easily opens and snaps shut, fantastic for quenching EMI/RFI
emissions from already existing equipment, power cords, cables, and connections.
Type 0443167251, approx. 225 ohms impedance at 100Mhz, very efficient and
inexpensive emission solution.
Seems like it would be easy to install and remove if it didn't work.
-------------- Original message --------------
-- AeroElectric-List message posted by: "Matt Prather"
The thing that is slightly frustrating about this whole discussion is that
when you buy the XCOM (or whatever else), presumably you are buying a comm
transceiver that is designed to be installed in an aircraft. And that it
will be wired into the aircraft power buss. Why the heck wasn't the radio
designed to perform correctly in that environment (without adding
additional "stuff")??
Eric, I agree that a LM317 or something more modern is a great way to
provide clean power to a device, but the XCOM's go for something like $1k.
I'm sure it has a regulated power supply built in...
Matt-
-- AeroElectric-List message posted by: "Eric M. Jones"
-- AeroElectric-List message posted by: luckymacy(at)comcast.net (lucky)
I have a XCOM 760 radio and I just checked into their website for the
first time
in a long time and leared that they now insist all their radios must be
fitted
with a 22,000uF/25VDC electrolytic capacitor, 85C. But I can't find
that exact match using google, e-bay or any of the couple of electronic
web site catalogs
I bookmarked.
Hi Lucky,
The general rule in capacitors is that you can always use a higher
voltage one; a bigger one unless it's a timing circuit. But as they say
the devil is in the details.
My computer motherboard had a dozen failed electrolytics (of the
TRILLIONS [YIKES!] made by a dozen Oriental comp
anies for Abit, Asus,
Aopen, Dell, HP, etc.,etc.,etc.; this may have been one of the greatest
engineering disasters of the decade, and there is an interesting tale
as to how it happened involving stolen RD secrets that didn't really
work out. There are some truly monster lawsuits in the works. But I
digress....). I replaced most of my motherboard's electrolytic
capacitors "E-caps"...but this is not for the faint-hearted.
I mention this as general information to spur thinking on using E-caps
when you can avoid it. But my opinion of using a 22,000 uF/25V cap to
eliminate noise from the B+ supply to the XCOM radio or any other
system is that this is a very poor way to do things. The capacitor
itself is an inch in diameter and two inches long and weighs over three
ounces. At 14V it contains a co
uple joules of energy. Most E-caps are
not rated for altitude cycling and temperature cycling unless you buy
the expensive military versions. Hmmm......
A far better technique than using a single fat electrolytic cap is to
use an in-line inductor and a capacitor. Certainly this is within the
ability of XCOM or anyone else with some knowledge of the subject. It
goes without saying...so I will say it...that several parts should be
added for the thing to work well:
1-A 0.1 uF ceramic cap across the big capacitor to stop high-frequency
brush noise.
2-An 18 volt zener across the capacitor to protect it from fast HV
transients.
3-Maybe a solid state resettable fuse in case the cap shorts.
4-Note that XCOM has the cap before the fuse. This needs some thinking.
<
BR> Bob N. has a good paper on this:
http://www.aeroelectric.com/articles/filter/RS_Noise_Filters.pdf , It
could be expanded to remedy this XCOM patch-job and provide a number of
user friendly filters.
A really robust and useful filter that is hardly ever used is an LM317
voltage regulator (or better yet some of its newer sisters). These
voltage regulators can do a much better filtering job than a pound of
capacitor and inductor, especially at audio frequencies.
Regards,
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge MA 01550-2705
(508) 764-2072
"Every act of conscious learning requires the willingness to suffer an
injury to one's self-esteem...."
-Thomas Szasz
&g
t;
________________________________________________________________________________
Subject: | Re: Was antennas Now Fuse Block Location |
Europa (Alfred Buess) a crit :
>
>Hi Bob,
>
>Have a look at this solution (kit: Europa XS)
>
>http://www.europaowners.org/Fuse-panel-in-picnic-tray
>
>
>
Alfred,
According to the photos there is an "always hot" bus along with the main
and essential bus. Is there a fuse protecting the feeder from the
battery to this bus under the panel ?
In our airplane (MCR 4S), the "always hot" busses are next to their
respective batteries and so do not need such a protection.
Just out of curiosity,
Regards,
Gilles Thesee
Grenoble, France
http://contrails.free.fr
________________________________________________________________________________
From: | "Dave Morris \"BigD\"" <BigD(at)DaveMorris.com> |
If you have a composite ship and would like to try a different idea in
antennas that does not require a ground plane, and your tail cone is around
31 inches in diameter, check out the Morris Com Loop antenna
http://www.DaveMorris.com/MorrisComLoop.cfm
Dave Morris
At 10:48 AM 10/2/2005, you wrote:
>
> << hi all, i have bobs book but i was looking for a detailed ''how to''
>set of directions
> for building a comm antenna. bobs drawings leave too much to my
>imagination
> and i end up with more questions than when i started . i am not at all
>familiar
> with electronics. that i can even send this e mail is a miracle. anything
>on
> a web site anyone knows of? from bobs book it seems that the antenna is
>very
> basic stuff but i need more help shopping for parts for one
>thing.....skip..... bob noffs>>
> 10/02/2005
>
> Hello Bob Noffs, Bob Nuckolls' advice to buy a ready made antenna is very
>sound. But it is possible to roll your own inexpensively and quickly.
>
> Go to this web site for specifices. http://www.rst-engr.com/
>
> Many of us have good working copper tape nav and comm antennas inside our
>composite airplanes.
>
> OC
>
>
________________________________________________________________________________
From: | "Europa (Alfred Buess)" <ykibuess(at)bluewin.ch> |
Subject: | Re: Was antennas Now Fuse Block Location |
Gilles,
You are right: The always hot bus is protected by a fuse just after the
battery. My battery is back in the fuselage and I wanted all the fuses
in the same place, that's why I have chosen this solution. In addition I
have a switch in the always hot bus feed wire just after the battery,
which is remotly operated from the cockpit. It allows me in case of an
emergency to cut all electric power just at the place of the battery.
Meilleures salutations,
Alfred
-----Ursprngliche Nachricht-----
Von: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] Im Auftrag von
Gilles Thesee
Gesendet: Sonntag, 2. Oktober 2005 19:46
An: aeroelectric-list(at)matronics.com
Betreff: Re: AW: AeroElectric-List: Re: Was antennas Now Fuse Block
Location
--> <Gilles.Thesee@ac-grenoble.fr>
Europa (Alfred Buess) a crit :
>-->
>
>Hi Bob,
>
>Have a look at this solution (kit: Europa XS)
>
>http://www.europaowners.org/Fuse-panel-in-picnic-tray
>
>
>
Alfred,
According to the photos there is an "always hot" bus along with the main
and essential bus. Is there a fuse protecting the feeder from the
battery to this bus under the panel ?
In our airplane (MCR 4S), the "always hot" busses are next to their
respective batteries and so do not need such a protection.
Just out of curiosity,
Regards,
Gilles Thesee
Grenoble, France
http://contrails.free.fr
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | Re: Second OVP as backup |
Thank you for sharing these thoughts with me. I'm going to publish
your original along with my reply on the AeroElectric List (of course
with your name removed) because it raises some important issues
which should be addressed an shared with all
>Hi Bob, I have installed in my GlaStar the B & C L-60 alternator and
>the LR3C-14 regulator wired as your recommend. I have added a second
>solenoid in series with the output of the alternator. This solenoid is
>activated by connecting the coil lead to ground. I have installed a
>power P MOS transistor with its gate lead connected to the (+)
>lead of one of your OVP modules. Added a 1000 ohm resistor from this
>gate lead to ground. Connected the source lead of the transistor to ground.
>Connected the drain to the solenoid coil. Your OVP unit is connected to
>the main power bus with a 5 amp breaker so that when the airplane is
>normally powered up the alternator solenoid is turned on. If there is
>an over voltage (I set this OVP at 16.0 volts) the OVP will blow the 5 amp
>breaker and disconnect the alternator via the transistor.
"Backup" systems are good when there is an unacceptable probability
that some "primary" system might cease to function and at the least,
increase pilot workload and at worst, cause catastrophic failures to
propagate across multiple systems.
A hand-held, totally independent GPS receiver is an EXCELLENT
example of what is nearly a bullet-proof backup for a device
that's mounted the panel, has 1000's of parts, depends on ship's
DC for power and is subject to severe damage if ship's power
is having a really bad day.
We've had some recent discussions about voltage regulators internal
to alternators wherein the block diagram or schematic of exemplar
regulators have a section labeled "OV Protection". I've cited
a rational for discounting this feature as adequate to the task
when the established (or uncertain) reliability of the regulator
section suggests that "backup" OV protection is warranted. It has
to do with the fact that OV protection is included on the same die
with the rest of the regulator chip's operating features.
The problem with this architecture is two-fold. I've never seen
a chip where there was any attempt to isolate the OVP function
to the extent that some failures of the voltage REGULATION loop
did not ALSO affect the ability of the OVP section to function.
This has always mystified me as to the thought processes of the
chip designers. The fact that they INCLUDE OV protection is a tacit
suggestion that it's a GOOD thing to do. I.e., the designer
recognizes that (1) there are failure modes within his/her product
capable of producing the OV condition and (2) there is no rational
methodology for stating that probability of regulator failure is
less than 10 to the minus -6 failure rates. THEREFORE: We'll
ADD the OVP feature. The reasoning then fails because it depends
on some of the same sense paths that the regulator uses for
operation (?????). If the designers know what they're doing, I
must assume that it's good marketing hype to put the little box
in there an mark it "OV Protection." However, when subjected to
well developed techniques for doing failure mode effects analysis
(FMEA) AND deducing mean time between failures (MTBF), this
little suite of components within the chip's topology do not
satisfy the design goals which have been adopted by the aviation
industry.
This is like analyzing the topology of a microprocessor's
arithmetic logic unit and deciding that an add, multiply,
divide and subtract section may be DEPENDED upon for proper
operation even if one of the other three sections on the
same chip has failed.
As systems designers and integrators we are faced with
a conundrum:
(1) Is the MTBF of EVERY chip offered to the automotive
industry so high that probability of an OV condition is sufficiently
remote as to be ignored?
(2) If the chip designer includes OV protection in his/her
design, then was it done to "back up" a questionable result
to the answer for (1) or was it included just so that the
marketing hype at the top of the chip's data sheet can include
"Over Voltage Protection is included on the die"?
Without good answers to these issues, I am driven by my
experiences and education in the certified side of aviation
to suggest that some form of TOTALLY INDEPENDENT OV protection
be included in OBAM aircraft designs that I recommend and
professionally stand behind as "the best I know how to do."
It appears that you've perceived some level of risk in the
LR-3/L60 combination that suggests some level of additional
backup is called for. Let us consider the facts that we
have to work with:
The L60 is a wound field, externally regulated alternator
that depends on a current supply to the "F" pin in order
to generate ANY output whatsoever. Hmmm . . . there IS
a condition to consider where a fault might occur between
the "F" and "B" leads INTERNALLY to the alternator. I have
seen this happen one time on a Mooney about 30 years ago.
The Electrical Systems Lead was all over his alternator
supplier for the way he bundled certain conductors within
the alternator which opened the doors for this possibility.
I don't believe this is an issue with the L60.
So, assuming that there IS value in adding a second OVP
system, I'll suggest there is no need to add a contactor
in series with the b-lead to effect a reliable shutdown.
Adding a smaller, much less stressed, relay or other solid
state device in series with the field supply to the LR-3
would suffice. Since the LR-3 now uses REMOTE but voltage
sensing separate from the field supply pin, there are no
risks to regulation stability for having inserted extra
components in series with the field power lead.
Now that we've down-sized the size of the task with
respect to stresses and need for robust components, let
us consider the value added by a decision to stack
OVP systems:
Consider this extreme. Suppose we had 10 OVP systems
any one of which would shut down a runaway alternator.
One might very comfortably state that this airplane will
NEVER suffer from catastrophic propagation of an OV
event. Now one has the task of keeping apprised of
LATENT failures. How many of the 10 systems are inoperative
after say 2,000 hours of inattention. Well, if only
one or two of the 10 have crapped, who cares? Okay,
lots of protection may offer one more restful sleep
but what are the trade-offs? What is the probability
of system failure NOT due to a real OV event but for
a failure within one of the OVP systems that produces
an unnecessary system shutdown?
All other things being equal, you're X times as likely
to suffer this condition where X is the number of OVP
systems installed.
Now, the real engineer works to optimize return on
investment for the decision as to how many OVP systems
are called for. This is something like sending your
elected officials to Washington but only after asking
and getting a rational answer to the following question:
"Sir . . . government needs cash to operate. Fine.
If taxation rates are zero percent, revenue to
government is obviously zero. If taxation rates
are 100%, revenues to government are still zero.
It stands to reason that somewhere between zero
and 100% taxation, revenues to government will
peak. It's like having just the right mixture in
your carburetor, having just the right amount of
salt or sugar in a recipe. Tell us sir. What is
the proper rate of taxation for the economy to
grow? How much can government confiscate in order
to maximize the support of government programs
without overburdening the economy such that any
INCREASE in taxation REDUCES revenues to government?"
I doubt that a single soul in government with any
power has an answer to that question supported on a
foundation of simple-ideas.
We have a similar problem. Too many protective
components and systems drives up cost of acquisition,
cost of ownership, weight, volume, complexity. All
of these things are good to minimize. Adding protection
to excess actually drives system reliability down.
Too few protective devices (that cost a few dollars
to install) expose us to risks of failure that have
very expensive and perhaps dangerous consequences
(one of the reasons I carry enough stuff in my flight
bag to continue flight to intended destination with
the panel completely dark). So, like adjusting levels
of taxation to achieve optimum cash flow, we need to
adjust levels of complexity with an eye toward the
"elegant solution": Highest acceptable reliability
with lowest cost of ownership.
Let us consider the LR-3's design. OV protection
shares no components or wiring with any other
functionality of the regulator assembly. In fact,
OVP, LV Warn, Voltage regulation are three independent
systems that share only a common enclosure. If
you were to split them into separate enclosures,
the rational is that system reliability would not
go up but down due to increase in numbers of wires
and installer fabricated connections. Therefore,
it was deduced about 20 years ago that the LR-3
should take its present form and aside from any
value added by modernizing the LR-3 to take advantage
of new technologies, I can see no compelling reasons
be concerned about reliability of the current
offering.
The OVP and Regulation sections would have MTBF
numbers on the order of 20,000 and 5,000 hours
each. The probability of having simultaneous
regulation AND over voltage protection failures
is extremely small. If you follow the recommended
manual testing of the OVP system every annual or
every oil change, that number gets better yet.
So, armed with this understanding, your decision
about adding more "protection" becomes one of deciding
whether (1) to err on the side of "safety" but to
tolerate reduced functional reliability and increased
cost or (2) is there sufficient confidence in the
design of the LR-3 as offered to use it "barefoot".
The LR-3 is a mature product with lineage going
back 20 years and somewhere around 5000 units
in service. Less than 5% of the fleet hardware has
been returned for service with most returns to repair
owner induced damage. Some have experienced circuit
failures but I've not heard of any COMPOUND failures
that resulted in an uncontrolled runaway. I've not
had feedback on the status of LR-3 returns for
a couple of years. I need to call up and get an
update.
It would seem that your first task is to see if your
concerns are rational. Is your departure from the
recommended optimal configuration driven by real,
rumored or imagined concerns?
> I also pre load the alternator
>with a 20 ohm resistor to stabilize the alternator when it is
>disconnected due to an OVP occurrence.
Not sure what this does for you. If you're wanting to
pre-load a load-dump event, know that the for the milliseconds
between onset of event and opening of the b-lead contactor,
field excitation and output current are building with alternator
output current bounded only by the machine's magnetics.
You could see a 70A+ dump into your 20 ohm resistor which
would only being to subdue the alternator at b-lead voltages
on the order of 70 * 20 or 1400 volts!
>Do you think this setup will give added protection in case
>the internal LR3C-14 OVP fails?
To have this be a concern, you'll FIRST have to experience
a runaway condition in the REGULATOR combined with a new
or latent failure in the OVP that's unable to react to the
regulator failure. This is statistically a very remote
event.
>The rational for this is to totally disconnect the alternator to provide
>a second level of protection for my $25,000.00 electronics in the
>airplane. Also could you provide the schematic for your latest OVP
>circuit. I believe the ones in your AeroElectric Connection manual
>are not the latest versions.
If you perceive some unacceptable levels of risk associated with
a single layer of OV protection, perhaps your concerns would be better
served with good preventative maintenance in an RG battery
that will stand off a runaway alternator for some period of time.
Unlike the 20 ohm resistor you proposed, a new 17 a.h. RG battery
will load a runaway 60A alternator to levels under 20 volts long enough
for a pilot to react to a big red, OV warning light and allow
manual shut-down of the system before damage occurs to any DO-160
qualified devices in the airplane.
There are no schematics in the 'Connection intended to guide the
builder in fabricating a functional OVP system. These are conceptual
only and offered to illustrate philosophies and not practice.
The article at
http://aeroelectric.com/articles/Crowbar_OV_Protection/Crowbar_C.pdf
was recently updated based on feedback from an astute builder who
correctly identified a deficiency in the original design.
I'll suggest you join us on the AeroElectric List for further
discussion of this or any other concerns you may have. See:
http://aeroelectric.com/consulting.html
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Subject: | 'lectric lockwashers |
>Comments/Questions: I just went through Chapters 8 and 9 and found no
>specific call out. Is there a preference between split lock washers and
>internal star lock washers for electrical connections? I'm talking about
>master and starter relays, battery posts and the starter, those big
>"honkers." I have noticed that the circuit breakers came with split lock
>washers, but those are #6 and #8. RV6A w/O-360.
Internal tooth star washers are preferred. Beryllium-Copper
or Phosphor_Bronze if you can get them . . . otherwise,
plated steel. Split-ring lockwashers are one step above spit
for locking and a half step above a flat washer for improved
condutivity.
Bob . . .
________________________________________________________________________________
From: | "bob noffs" <icubob(at)newnorth.net> |
hi bob, can i benefit from using your audio isolation amp board with just a transceiver
and headsets[ no music system]
bob noffs, woodruff, wi
________________________________________________________________________________
From: | Ken <klehman(at)albedo.net> |
Subject: | Re: Why are wire strands tinned ? |
As someone who has occasionally worked on 10+ year old cars in the
rust/salt belt, I would agree that there should be a "special place" for
manufacturers who install untinned wire in automobiles as well. I've
seen every strand badly corroded for the entire length of the wire.
Presumably moisture wicks its way many feet up the wires.
Ken
>An airplane is typically in a much more benign environment unless it is
>based near salt water. Nonetheless, I think tinned wire is a real good
>idea.
>
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
>
>hi bob, can i benefit from using your audio isolation amp board with just
>a transceiver and headsets[ no music system]
> bob noffs, woodruff, wi
Very simple audio systems are illustrated in Chapter 18:
http://aeroelectric.com/articles/Rev11/18Audio_R11.pdf
. . . specifically in Figure 18-7 and associated text.
An airplane with one or two sources of audio does not
benefit from an isolation amplifier.
Bob . . .
________________________________________________________________________________
From: | "Eric M. Jones" <emjones(at)charter.net> |
Subject: | Re: capacitor and music jack help needed |
>What if I just got something like the one at
>http://www.sphere.bc.ca/test/inductors.html
>Fair Rite Snap-It RFI Ferrite Suppressors....Fits wires/bundles up to
>10mm/0.390
>inch in diameter, easily opens and snaps shut, fantastic for quenching
>EMI/RFI
>emissions from already existing equipment, power cords, cables, and
>connections.
>Type 0443167251, approx. 225 ohms impedance at 100Mhz, very efficient and
>inexpensive emission solution.
>Seems like it would be easy to install and remove if it didn't work.
>Lucky
Lucky,
It won't do anything for you. The snap-on ferrites are good for very high
frequencies only--like MegaHertz and GigaHertz. We need a "Very Low Pass
Filter"
The thing we need for kiloHertz noise is an inductor that is a substantial
physical size and in the milliHenry range. The capacitors we need are also
much smaller than 22kuF. There are a zillion prescriptions for noise
filters. Radio Shack used to carry suitable chokes. But the choices are
slimmer now. If you know a little about the subject you can design filters
with many available online calculators like the excellent free one from
www.nuhertz.com . The newest noise filters are "active" filters, which means
they have electronics that vary the filter response as needed.
I recommend getting noise filters from J.C. Whitney or Crutchfield or any
big car-audio place. They have good ones for short money. Just Google "noise
filters".
Remember-- you are way ahead if you stop the noise at the source. My
airplane will have a high current B+ noise filter near the alternator, and
one or more low current devices on the "avionics bus" or associated with
radios and intercoms wirings.
Regards,
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge MA 01550-2705
(508) 764-2072
Ring the bells that still can ring
Forget your perfect offering
There is a crack in everything
That's how the light gets in.
--Leonard Cohen
________________________________________________________________________________
From: | "Roger Evenson" <revenson(at)comcast.net> |
How about three sources of audio? Will three sources work with resistors
only and no isolation amp?
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckollsr(at)cox.net>
Subject: Re: AeroElectric-List:
>
>
>
>>
>>hi bob, can i benefit from using your audio isolation amp board with just
>>a transceiver and headsets[ no music system]
>> bob noffs, woodruff, wi
>
>
> Very simple audio systems are illustrated in Chapter 18:
>
> http://aeroelectric.com/articles/Rev11/18Audio_R11.pdf
>
> . . . specifically in Figure 18-7 and associated text.
> An airplane with one or two sources of audio does not
> benefit from an isolation amplifier.
>
> Bob . . .
>
>
>
________________________________________________________________________________
From: | Jon Goguen <jon.goguen(at)umassmed.edu> |
Subject: | Vacuum pad alternator options for Rotax |
Does anyone have experience with the modified Densei alternators that
mount on the vacuum pad of Rotax engines (esp. 912S) and are sold by
Flight Crafters, Lockwood aviation, and perhaps some others? As I
understand it, these are essentially standard automotive devices with
internal regulation mechanically modified to fit the vacuum pad. I'm
particularly interested in their current capability. I'm told by the
vendors that they'll provide 40 amps at 2800 rpm, a speed compatible
with the 912S vacuum pad rpm in cruise. I had originally intended to
use the B&C Systems SD20, but--as pointed out to me by Paul Wilson on
the list and confirmed by B&C--the output of the SD20 is only 12 amps
due to the low rpm at the pad. Lockwood says the Densei alternative is
especially popular in Europas. Anyone know how well these things work
in real life?
Thanks!
Jon
Jon Goguen
jon.goguen(at)umassmed.edu
Central Massachusetts
Kitfox Series V Rotax 912S / N456JG (reserved)
Complete except for electrics and avionics
________________________________________________________________________________
From: | "Bill Denton" <bdenton(at)bdenton.com> |
Subject: | Vacuum pad alternator options for Rotax |
Rotax also offers an external alternator for the 912; part number: 887254.
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Jon
Goguen
Subject: AeroElectric-List: Vacuum pad alternator options for Rotax
Does anyone have experience with the modified Densei alternators that
mount on the vacuum pad of Rotax engines (esp. 912S) and are sold by
Flight Crafters, Lockwood aviation, and perhaps some others? As I
understand it, these are essentially standard automotive devices with
internal regulation mechanically modified to fit the vacuum pad. I'm
particularly interested in their current capability. I'm told by the
vendors that they'll provide 40 amps at 2800 rpm, a speed compatible
with the 912S vacuum pad rpm in cruise. I had originally intended to
use the B&C Systems SD20, but--as pointed out to me by Paul Wilson on
the list and confirmed by B&C--the output of the SD20 is only 12 amps
due to the low rpm at the pad. Lockwood says the Densei alternative is
especially popular in Europas. Anyone know how well these things work
in real life?
Thanks!
Jon
Jon Goguen
jon.goguen(at)umassmed.edu
Central Massachusetts
Kitfox Series V Rotax 912S / N456JG (reserved)
Complete except for electrics and avionics
________________________________________________________________________________
From: | Jon Goguen <jon.goguen(at)umassmed.edu> |
Subject: | Re: Vacuum pad alternator options for Rotax |
Bill,
Thanks. Unfortunately, that option doesn't fit under the cowl without
a lot of modification.
Regards,
Jon
Jon D. Goguen, Ph. D.
Department of Molecular Genetics and Microbiology
University of Massachusetts Medical School
55 Lake Avenue North
Worcester, MA 01655
Phone 508.856.2490
Fax 508.856.5920
On Oct 3, 2005, at 12:16 PM, Bill Denton wrote:
>
>
> Rotax also offers an external alternator for the 912; part number:
> 887254.
>
>
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Jon
> Goguen
> To: aeroelectric-list(at)matronics.com
> Subject: AeroElectric-List: Vacuum pad alternator options for Rotax
>
>
>
>
> Does anyone have experience with the modified Densei alternators that
> mount on the vacuum pad of Rotax engines (esp. 912S) and are sold by
> Flight Crafters, Lockwood aviation, and perhaps some others? As I
> understand it, these are essentially standard automotive devices with
> internal regulation mechanically modified to fit the vacuum pad. I'm
> particularly interested in their current capability. I'm told by the
> vendors that they'll provide 40 amps at 2800 rpm, a speed compatible
> with the 912S vacuum pad rpm in cruise. I had originally intended to
> use the B&C Systems SD20, but--as pointed out to me by Paul Wilson on
> the list and confirmed by B&C--the output of the SD20 is only 12 amps
> due to the low rpm at the pad. Lockwood says the Densei alternative is
> especially popular in Europas. Anyone know how well these things work
> in real life?
>
> Thanks!
>
> Jon
>
> Jon Goguen
> jon.goguen(at)umassmed.edu
> Central Massachusetts
> Kitfox Series V Rotax 912S / N456JG (reserved)
> Complete except for electrics and avionics
>
>
________________________________________________________________________________
From: | "Greg Campbell" <GregCampbellUSA(at)comcast.net> |
Subject: | 5vDC Power Supply... |
Hi,
I'm going to wire in a Garmin GPS 18 5Hz backup GPS receiver to my EFIS.
http://www.garmin.com/products/gps185hz/
and it requires 4.0 to 5.5 vdc input, drawing 65 mA @ 5vdc.
http://www.garmin.com/products/gps185hz/spec.html
For initial testing, I'm using 4 AA NiCd's (in series, 4.8vDC) rated at 2300mAh
each.
This is fine as long as I remember to charge them up, and turn the GPS off
between uses. (It's just a backup GPS Input for the EFIS & Autopilot).
For the final installation, I'd like to power it off 12vdc Ships Power.
I bought a 5vDC "Fixed Voltage Regulator" that supplies up to 1 Amp.
http://www.radioshack.com/product.asp?catalog%5FnameCTLG&product%5Fid276-1770
The one I got didn't have any instructions, and there is no spec sheet at www.RadioShack.com
Do these typically require external resistors? Heat sinks? etc ?
Any advice on wiring up the voltage regulator?
Then, to make things a bit fancier - I was hoping to run it from Ships Power
AND have a small AA or AAA battery backup pack for the GPS receiver.
The "ideal" battery backup system would:
1) Automatically charge up the NiCd's whenever the ship's power is ON
2) Not "overcharge" the NiCds or charge them at more than about 0.8 Amps.
3) Automatically power the GPS from the NiCds whenever the 5vDC power is "lost"
4) Automatically shut off the GPS after 6 to 8 hours so the NiCds don't drain completely.
Any advice on wiring up a simple and elegant backup battery?
Thanks in advance,
Greg
________________________________________________________________________________
From: | "Will N. Stevenson" <will(at)wavecable.com> |
Eric,
I'm new on this list and am overjoyed to find both you and Bob as sources of
September 20, 2005 - October 03, 2005
AeroElectric-Archive.digest.vol-ev