Today's Message Index:
----------------------
1. 05:53 AM - Re: The fatwire ground blues . . . (Johnson, Phillip (EXP))
2. 06:44 AM - Re: Z-11 question for the electrically (Robert L. Nuckolls, III)
3. 06:49 AM - Re: The fatwire ground blues . . . (Robert L. Nuckolls, III)
4. 06:51 AM - Re: Audio Iso Amp problem (corrected) (Robert L. Nuckolls, III)
5. 07:22 AM - Re: The fatwire ground blues . . . (Joseph Larson)
6. 07:44 AM - Re: Crowbar CB "problem" question (plaurence@the-beach.net)
7. 07:58 AM - Audio Iso Amp Problem (Fiveonepw@AOL.COM)
8. 08:36 AM - Re: Crowbar CB "problem" question (LarryRobertHelming)
9. 01:49 PM - B&C website problems (gert)
10. 02:42 PM - Re: B&C website problems (plaurence@the-beach.net)
11. 02:43 PM - Re: B&C website problems (Robert L. Nuckolls, III)
12. 03:01 PM - Re:Real data on OVP/etc (disinterested?) ()
13. 06:41 PM - Re: B&C website problems (gert)
14. 07:01 PM - Screw terminals and Vision Microsystems' 1000 (Malcolm Thomson)
15. 08:25 PM - Electric Tail wheel tug (Gary Graham)
16. 08:37 PM - Re: The fatwire ground blues . . . (Guy Buchanan)
17. 08:54 PM - Re: Screw terminals and Vision (Robert L. Nuckolls, III)
18. 09:01 PM - Re: The fatwire ground blues . . . (Robert L. Nuckolls, III)
19. 09:13 PM - Power/ground terminal blocks (Steve Ruse)
Message 1
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| Subject: | Re: The fatwire ground blues . . . |
--> AeroElectric-List message posted by: "Johnson, Phillip (EXP)" <phillip.johnson@lmco.com>
The problem of poor grounding whilst cranking the engine has always been a concern
of mine. To overcome this I have the battery ground connected directly to
the engine and then all grounds connect to the engine. This way no cranking current
flows through the sensor grounds under any conditions.
Phillip Johnson
Message 2
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| Subject: | Re: Z-11 question for the electrically |
challenged
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
challenged
At 07:24 PM 8/3/2005 -0400, you wrote:
>--> AeroElectric-List message posted by: joelrhaynes@aol.com
>
>Bob,
>I will shortly be wiring my RV-7a according to your Z-11 schematic and
>will be using Van's internally regulated 60 amp alternator. If I choose
>not to employ OV protection, I assume that I simply connect terminal #4 of
>the Battery/Alt switch depicted on Z-11 to the field terminal of the
>alternator with a fuse (5A?) in between. Please advise if I am in error.
I wish I had some good data to offer you.
As you may have gathered from much of the discussion
concerning internally regulated alternators here
on the List, the internally regulated alternator
as a class of product is a moving target.
First, there is no fixed protocol under which these
alternators respond to the command signal that comes
in the back on the small wire. Some alternators, I'm
told, will turn ON and OFF in response to bus voltage
supplied to the command input. Others will only turn
ON and are not controllable from the panel switch
after energized for the first time.
Second, in spite of exemplary demonstrations of reliability
in the automotive world (I've NEVER experienced an
OV event at any time in 40+ years of driving) we know
that numbers of our brethren HAVE experienced OV events
in internally regulated machines with various outcomes.
As a systems designer, I've taken the position that
my recommendations should be crafted for the most universal
application. I KNOW that 99% of all externally regulated
alternators will run well with 90% of all alternator
regulator products. I KNOW that removing field
excitation from and operating alternator will shut it
off. I KNOW there are useful techniques for sensing
over voltage and removing field excitation. Therefore,
combinations of externally regulated alternator, a regulator,
an OV protection system -AND- ACTIVE NOTIFICATION OF LOW
VOLTAGE offers a high degree of risk reduction
against catastrophic failures that propagate throughout the
system.
>Also, I gather from recent bandwidth that during normal operation, one
>should avoid switching the alternator off until the engine has shut down
>as this may be unhealthy for Van's alternator (or perhaps all alternators?).
Assuming that the alternator Van supplies will respond
to both ON and OFF commands, there is no risk for turning
the alternator ON or OFF while operating.
When we went conducted the exercise of trying to make
and automotive alternator look and behave like an
aircraft alternator, we discovered some unhappy
tradeoffs. Adding a b-lead contactor to assure positive
control of ANY internally regulated alternator, we
created a possibility of killing an perfectly good
working alternator by turning it OFF while loaded.
The risk of this happening goes away when we abandoned
the technique for exercising full control over the
alternator. At the same time, we lost the ability
to exercise protection against OV runaway.
>I know from flying Cessnas that occasionally the alternator will trip out
>and can be brought back on line via cycling of the alt switch. Will that
>scenario apply in your Z-11 schematic with an internally regulated alternator?
If you install Van's alternator per his recommendations,
there will be no OV protection to trip out. Therefore,
no reason to "reset" it by exercising the alternator control
switch.
I have no test data or narrative of an experiment
that defines how Van's alternator works. Perhaps someone
on the list is flying with Van's alternator who
can enlighten us.
Further, I have no knowledge of Van's configuration
management on alternators he sells. Its possible that
one batch of alternators may be fully controllable while
the next batch is Turn-On only.
Lack of data makes it impossible for one to
offer considered critical review of the system or to
suggest system integration or operational techniques.
Sorry I can't be more helpful at the moment.
Bob . . .
Message 3
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| Subject: | Re: The fatwire ground blues . . . |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 08:15 AM 8/4/2005 -0400, you wrote:
>--> AeroElectric-List message posted by: "Johnson, Phillip (EXP)"
><phillip.johnson@lmco.com>
>
>The problem of poor grounding whilst cranking the engine has always been a
>concern of mine. To overcome this I have the battery ground connected
>directly to the engine and then all grounds connect to the engine. This
>way no cranking current flows through the sensor grounds under any conditions.
The only way one gets cranking current to flow in undesired
pathways is when desired pathways coexist with undesired
pathways. The ideal ground system eliminates parallel
pathways so that ANY open connection produces a passive
failure.
Sensors that ground to their mounting on the engine
should not be fitted with a second ground path. Most
suppliers of such sensors suggest a means for isolating
the sensor from engine case ground -or- they call for
the instrument that reads the sensor to ground to the
engine instead of behind the panel.
This is good practice BOTH for signal integrity by
elimination of ground loops and system safety against
burning bitty wires when big wires get unhooked.
Bob . . .
Message 4
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| Subject: | Re: Audio Iso Amp problem (corrected) |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 05:12 PM 8/3/2005 -0500, you wrote:
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
<nuckollsr@cox.net>
At 03:36 PM 8/3/2005 -0400, you wrote:
>--> AeroElectric-List message posted by: Fiveonepw@aol.com
>
>Bob-
>
>My kit-built amp exhibits poor audio input from my Microair 760- the audio is
>"clipped?" where perhaps 1/3 of the signal gets through resulting in barely
>audible reception. By "clipped" I mean it is like I will hear perhaps 100
>msec
>of audio with about 200 msec silence between. (WAG at time intervals) The
>audio alarm from my EIS4000 engine monitor sounds perfect, however- a nice
>clean "beep" simultaneously with the alarm light. I changed the 150 ohm
>input resistors with 180s with no noticeable difference.
>
>It is the same unit I sent you for testing some time ago and you reported it
>was fine. Autocad dwg of audio system available if desired. Suggestions?
Any changes to the series input resistors should be made in 2x/0.5x (was
1x/0.5x) steps.
For example, if you want to reduce gain of any one channel, the MINIMUM
useful increase would be from 150 to 300 ohms. If still too hot, go to
600 ohms, etc.
By the same token, if you need more gain, reduce a 150 ohm resistor
to 75 ohms first, then 36 ohms.
I'm hearing that some radios like to be "loaded" heavier on their
phones output signals than what the amplifier provides. Before you
change the 180 to anything else, try putting anything from 50 to
100 ohms ACROSS the Microair 760's headphones output leads.
What your describing sounds more like some kind of bias shift
than overloading. The "dummy" load may help more than anything
else. Let us know what you find.
I've had some good feedback from about a dozen builders of the
audio isolation amplifier with some suggestions for improvements.
I'm considering a second generation version . . . but to fit in
the same package, we'll have to go surface mounted parts which
is probably more than most builders want to tackle. If we do
it, the amplifier will offered as a plug-n-play assembly.
There's one going into a certified ship under a 337 installed
by what appears to be a really savvy technician. I asked him
to feed back impressions and suggestions too. I think this
gizmo is ripe for an upgrade but there's no reason we can't
make it do what you need done.
Bob . . .
--
-- 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
Message 5
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| Subject: | Re: The fatwire ground blues . . . |
--> AeroElectric-List message posted by: Joseph Larson <jpl@showpage.org>
Bob, your response below sounds very important. Up until your last
sentence, I was thinking, "What's wrong with a few extra grounds?
They should all be at the same potential, so it seems like extra
insurance." Then you mentioned the part about bitty wires taking
loads they can't handle, and suddenly most of the rest makes sense.
In other words, every device should have exactly one path IN for
power and exactly one path OUT back to the battery. Is that what
you're saying? This is how you can properly size the wires used,
because the ground for one device won't inadvertently be used as
ground for another device, resulting in an overloaded wire.
Can you explain what a ground loop is and provide an example of how
one creates one, so I can get a better feel for what to avoid?
Is it okay to "chain" a the ground of a bunch of devices together
before bringing them all to the battery?
-Joe
On Aug 4, 2005, at 8:47 AM, Robert L. Nuckolls, III wrote:
>
> The only way one gets cranking current to flow in undesired
> pathways is when desired pathways coexist with undesired
> pathways. The ideal ground system eliminates parallel
> pathways so that ANY open connection produces a passive
> failure.
>
> Sensors that ground to their mounting on the engine
> should not be fitted with a second ground path. Most
> suppliers of such sensors suggest a means for isolating
> the sensor from engine case ground -or- they call for
> the instrument that reads the sensor to ground to the
> engine instead of behind the panel.
>
> This is good practice BOTH for signal integrity by
> elimination of ground loops and system safety against
> burning bitty wires when big wires get unhooked.
Message 6
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| Subject: | Re: Crowbar CB "problem" question |
--> AeroElectric-List message posted by: plaurence@the-beach.net
My three cents worth-
Wired a Velocity with dual alternators using B & C's L-60, SD-20, LR3-14 and
SB1A-14.
We have 150 hours on the hobbs with these components with no overvoltage trips.
We did have the SD-20
fail a few weeks ago and it was promptly replaced by the company. Goog folks!
Peter
On 3 Aug 2005 at 16:15, bakerocb@cox.net wrote:
> --> AeroElectric-List message posted by: <bakerocb@cox.net>
>
> AeroElectric-List message previously posted by: Richard Riley
> <richard@riley.net>
>
> <<For those that have experience with an external regulator -
> particularly one of the B&C regulators - how often do the nuisance
> trips occur?
>
> If we're worried about the nuisance trips degrading field CB's, would
> it be a reasonable fix to replace those CBs at annual?>>
>
> 8/3/2005
>
> Hello Richard, 100 hours plus on my plane with an externally regulated
> (B&C), gear driven, 60 AMP alternator with no nuisance trips.
>
> Replacing CB's can be a bitch because frequently they are fastened 2
> or 3 or more to a brass bar. It can take a significant amount of
> unfastening and then reassembling to replace one CB.
>
> OC
>
>
>
>
>
>
>
Message 7
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| Subject: | Audio Iso Amp Problem |
--> AeroElectric-List message posted by: Fiveonepw@aol.com
Bob-
You wrote:
=A0=A0 I'm hearing that some radios like to be "loaded" heavier on their
=A0=A0 phones output signals than what the amplifier provides. Before you
=A0=A0 change the 180 to anything else, try putting anything from 50 to
=A0=A0 100 ohms ACROSS the Microair 760's headphones output leads.
I notice in the latest Iso Amp dwgs a Failsafe Headset (and mic) Jack added-
my installation precedes this and I would like to incorporate the feature.
Would adding the load resistor you mention above between the ring and tip
terminals on the new headset jack be appropriate to the task?
In addition, installing the Failsafe Headset Jack and using a male phone plug
with a small value pot wired to its terminals would allow "fine tuning" the
appropriate resistance prior to installing the resistor?
These jacks would also require insulation from airframe as well, I surmise...
Thanks again-
Mark Phillips -6A
Message 8
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| Subject: | Re: Crowbar CB "problem" question |
--> AeroElectric-List message posted by: "LarryRobertHelming" <lhelming@sigecom.net>
I have the B&C LR3 regulator with Vans 30 amp externally controlled
alternator. Wired per Bob's manual. No trips with 52 hours on the meter.
Indiana Larry, RV7 Tip Up It Flies
Teamwork: " A lot of people doing exactly what I say."
(Marketing exec., Citrix Corp.)
----- Original Message -----
From: "Richard Riley" <richard@RILEY.NET>
Subject: Re: AeroElectric-List: Crowbar CB "problem" question
> --> AeroElectric-List message posted by: Richard Riley <richard@riley.net>
>
> For those that have experience with an external regulator -
> particularly one of the B&C regulators - how often do the nuisance trips
> occur?
>
> If we're worried about the nuisance trips degrading field CB's, would
> it be a reasonable fix to replace those CBs at annual?
>
>
>
Message 9
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| Subject: | B&C website problems |
--> AeroElectric-List message posted by: gert <gert.v@sbcglobal.net>
hmmm
no link anymore from 'lectric Bob's website to B&C ???
B&C website, giving me errors when linking to products???
something going on??
--
is subject to a download and archival fee in the amount of $500
Message 10
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| Subject: | Re: B&C website problems |
--> AeroElectric-List message posted by: plaurence@the-beach.net
Try http://www.bandcspecialty.com/
Peter
On 4 Aug 2005 at 15:48, gert wrote:
> --> AeroElectric-List message posted by: gert <gert.v@sbcglobal.net>
>
> hmmm
>
> no link anymore from 'lectric Bob's website to B&C ???
>
> B&C website, giving me errors when linking to products???
>
> something going on??
>
> --
>
>
> is subject to a download and archival fee in the amount of $500
>
>
>
>
>
>
>
Message 11
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| Subject: | Re: B&C website problems |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 03:48 PM 8/4/2005 -0500, you wrote:
>--> AeroElectric-List message posted by: gert <gert.v@sbcglobal.net>
>
>hmmm
>
>no link anymore from 'lectric Bob's website to B&C ???
>
>B&C website, giving me errors when linking to products???
>
>something going on??
We removed the link in preparation for some major changes
coming to our website which will include some whippy new
products.
I've had a few "page not found" type errors when roaming
the B&C site. It wouldn't hurt to drop them a note when
you discover one.
Bob . . .
Message 12
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| Subject: | Re:Real data on OVP/etc (disinterested?) |
--> AeroElectric-List message posted by: <gmcjetpilot@yahoo.com>
--> AeroElectric-List message posted by: "Jack Eckdahl"
><jeckdahl@sjrwmd.com>
>
>George: The alternator that failed was a Nippon Denso, 60 amp,
>internally regulated. I'm not sure that my experience should cause
>others to avoid this unit. I know that hundreds of airplanes are flying
>successfully with them. However, if you read Bob's most recent post,
>you might decide to avoid all internal regulated alternators.
>
Hi Jack:
> "Jack Eckdahl" wrote:
>However, if you read Bob's most recent post, you might decide to avoid all internal
>regulated alternators.
No Sir, I still think internally regulated alternators (ND in particular) are a
fine choice, without an adding on an OV protection device (crow bar). By fine
choice I mean safe & reliable. It is lighter, cheaper, simpler and less expensive
than an external regulated alternator. There is nothing wrong with a crow
bar, not with standing the little technical minutiae.
I have a great respect for Bob's opinions, which are based on his knowledge, experience,
standard aerospace practices and certification regulations, which is
all-good.
To make an analogy: Lets make a stew by cooking-up several pounds of knowledge
& experience. Than add an ounce of spice called opinion. The whole flavor of the
stew is influence and changed by that opinion. The taste is still good, but
it's a different flavored stew than if you used a different spice (opinion).
That does not mean a stew with another spice (opinion) is bad.
Bob has strong opinions, and is the guru of electrons who gives out design advice
thru this forum, seminars and his book. He has to believe and understand the
info he gives out. I don't blame him for not supporting IR alternators. He
does not have detailed info on the design or can he control it. However that does
not make IR alternators a poor choice or dangerous. In fact it is superior
in many ways to the method of DC power generation Bob campaigns. Bob does not
talk to the advantages of the IR alternator, but to be fair he does not say it
is bad. He just cant recommend it, and given the choices he must pick one idea
and back-up that one idea he feels is best overall for most applications. Thats
OK.
Pick your spice, make your stew, eat and enjoy. If you get indigestion it is your
own fault. I don't criticize other Cooks for using curry spice.
Bob says a crow bar and external VR is the best way to go; he has good reasons
to recommend it; he is comfortable with it. He knows how it works or should work.
Bob is not comfortable with IR regulators because he can't control the field
directly, in other words he does not trust the IC chip and the one field driver
transistor. Plus he has always used external voltage regulators at work.
Fair enough.
I do trust the IC chip and drive transistor. Why? They are proven in millions of
cars, trucks and industrial equipment, including a good lot of kit planes as
well. You can't get the FAA to certify an alternator on this basis, but again
who cares if you have a kit plane.
The electronic and auto industry has studied and tested these electronic components,
like the ones inside a ND alternator, i.e., transistors and IC circuits.
They have a known failure time in the millions of hours.
The big hang up with Bob and others is the one drive transistor (external to the
IC) could short out and by-pass the IC chips control of the alternator. How
likely is this? The chance is slim to none, and is proven every day when millions
of these alternators work with out fail, day after day, year after year, 100s
and 1,000s of hours every year.
I think a ND alternator with IR, without an added on crow bar, has the right spices
for my stew (electrical system) and is delicious.
Bob bases his design philosophy in part on a thought process of "how could you
certify this?" Well if you have an experimental you don't care or need a certified
accessory. I agree an IR alternator is hard if not impossible to certify
with the FAA as is, without spending mega dollars doing it. So the inertia of
the industry is to stay with what you know, externally regulated alternators.
You can't certify an accessory based on field service history in cars and kit
planes alone, but it sure speaks to its reliability. Good enough for me and many
other builders.
Bob works in the certified field; this is his line of work and influences his opinion.
Not that there is anything wrong with that. However if you think FAA certified
makes something better, you might consider a 1950's Delco or Ford Prestolite
automotive generator and mechanical points voltage regulator are FAA certified
on aircraft! Is that better than a small light Denso alternator with
IR? Bob's crow bar is not certified. B&C alternators & regulators are not certified.
Does that make them bad? NO. There is no magic to FAA certification. We
have the freedom to use Denso alternators in our kit planes, an in my opinion
we should exercise that option, not that Bob's baseline system is bad. I just
don't think it automatically should be the De facto design. No disrespect to
Bob, and sorry if that offends anyone.
Why has Bob's crow bar experienced premature trips? Stuff happens. I read about
the capacitor fix and understand why it helped. It seems to me, as an electronics
amateur, whenever you have transient conditions (dv/dt), throw a good old
capacitor in the mix. It always seems to mellow a circuit out. (mellow - a non-technical
term for filter to dampen transient voltage spikes.) When in doubt
put a capacitor in. (kidding)
There is never a 100% guarantee any device, including a simple crow bar or a ND
alternator will always work as designed. Simple things like a crow bar & circuit
breaker should work as Bob would point out. The same applies to Denso alternators.
However the idea propagated that a Denso failure means a colossal OV
condition is not valid. The usual Denso failure mode is passive, by just dying.
People want a 100% guarantees about everything in life and what they put on their
aircraft. Keep it simple; consider a stand alone Denso as an elegant simple
solution. Consider that crow bar could fail passively and not work when needed
without the pilot being aware of it. Bob said this is unlikely. BINGO. I agree
a simple crow bar should work, with emphasis on should. Same with a Denso alternator,
it is unlikely you will have an OV condition. At least the ND alternator
has a built in fault light (which will indicate many faults). Nothing is
perfect. Take a chance on life
> "Jack Eckdahl" wrote:
>George: The alternator that failed was a Nippon Denso, 60 amp, internally regulated.
Jack: I recall under peculiar conditions you observed your ND alternator going
to 16 volts. Also with the ALT switched off it produced power after starting the
engine. The technique of turning the alternator on after start was your normal
procedure. Obviously something was different than before, since it always
worked well and would not make power until switching it on. You also noted that
voltage varied 13 to 16 with load. By using a normal procedure of manually switching
the alternator ON after starting and OFF before shut down, you forced
an abrupt ON/OFF thru the regulator. This is known to cause grief. (Read below-The
IC chip inside the alternator is a microprocessor and its internal protections
only work if it is powered during engine start and stop.)
I recall pointing out sources for brand new 60 amp ND alternators to you. Not sure
what you ended up doing but assume you are flying around FHD with your new
ND alternator. My prediction is if you stop the practice of switching the alternator
ON/OFF manually and get a NEW 60 amp ND alternator, you will have a lifetime
of trouble free alternator service (with out crow bar). Odds are in your
favor. The only other recommendation I have is add a cooling blast tube to the
rear of the alternator, and avoid continuous operations above +30 amps. Heat
is the killer of semi-conductors.
ND alternators have an IC chip that provides many safety and fault protection functions
including OV protection. In fact this microprocessor chip may have thousands
of transistors VS. a Plain-Jane external VR with 2 or 4 transistors.
Therefore doing abrupt things repeatedly stresses the chip overtime. It just was
not designed to be used like that. You got away with it for a while, but eventually
is started to fail (with out dramatic affect I might add).
The IC chip also provides soft starts and load dump protection. SOFT START means
a large demand will not cause the alternator to instantaneously slam full open
but will ramp up to avoid a voltage overshoot. LOAD DUMP protection, keeps
voltage variation to a min with a large drop in load. When I say load dump I don't
mean dropping the B-lead abruptly with an OV relay, I mean turning the landing
lights OFF. I would like to see a two-transistor external voltage regulator
do this. The typical IR is more advanced than the typical ER.
Paul's http://www.periheliondesign.com/suppressors.htm may solve the problem of killing a healthy ND alternators when a nuisance trip of a B-lead OV relay opening while the alternator is under load. Who knows, it can't hurt. However my electrical system design philosophy (the stew I am cooking) is to keep it simple. I assume the chance of my alternator going into a real out-O-control OV condition from a drive transistor short is so small I accept. Just like I accept my single engine will continue to turn and my single wing spar will not fail in flight. (Sometimes these also fail, but we maintain them and fly within limits to assure they get us back on the ground safely.)
There has been much rhetoric about the dangers of IR alternators and the evil of
that one field drive transistor. The theory is the transistor failure inside
the IR bypasses the OV protection of the IC chip. This in turn causes the mother
of all OV conditions. Not to beat the horse to death (which is a bloody caucus
being picked at by vultures at this point), but this scenario is a theory
NOT born out by the proven reliability in service. No car or kit plane I know
of has ever had this condition from my research. I looked high and low and found
nothing, nada, zip, zero. I am not saying it has never happened or cant happen
(it can in theory), but there is no proof or documentation it has. If we
are going to get scientifically rigorous, than we need the data, otherwise it
is ignorant, to use Bobs words.
Show me any cases of a ND alternator having a real honest to goodness (documented)
shorted field drive transistor resulting in an over-voltage condition, urban
legend aside. Sporadic OV module problems are much more prolific than the non-existent
alleged alternator run-a-way.
The voltage problem (16 volts) you had was far from a wild run-a-way. Voltage Run-a-way
elicits thoughts of a train going down the mountain with no brakes, terror,
panic, destruction and emotion. That is why when you tie the BAT master
and ALT together, so the alternator is turned on automatically (i.e., DPST switch).
If you need to shut the ALT down, manually pull the CB.
> "Jack Eckdahl" wrote:
>I'm not sure that my experience should cause others to avoid this unit.
In my opinion using a ND alternator as is, provides an acceptable risk while gaining
a lighter, simpler and cost effective electrical power source. Everything
in aviation has risk, and the outcome depends on how you manage these risks.
Bob says that crow bar failure is not likely. BINGO!! I am saying run-a-way
voltage in a ND alternator is not likely. Again my opinion aside, facts like the
field service history of ND alternators indicate their IR alternator are pretty
darn good. I dont think the Japanese ND engineers that designed these devices
are ignorant. (The auto industry is very aware of OV and has lots of electronics
to protect.)
Jack: If you replaced your rebuilt alternator with a new one, assuming you have
stopped flipping the alternator ON an OFF manually, you will be fine. The BAT
master should turn the ALT on simultaneously (i.e., DPST switch). If you need
to disable the alternator pull the CB.
> "Jack Eckdahl" wrote:
>I know that hundreds of airplanes are flying successfully with them.
I have no idea about aftermarket rebuilds or second tier replacement parts VS.
OEM parts from ND. ND alternators can be bought new easily at discounted price
if you shop around. The medium frame 60 amp ND's are more readily available as
a rebuild, but they can be bought new if you look.
Compare the price of a B&C and an over the counter stock 60 amp ND alternator.
The whole B&C kit $820: alternator, regulator and brackets. If you buy a New ND
alternator ($180 retail, $120 discounted), brackets and parts (approx $40-$60),
your cost is about $250, the cost of Vans 60 amp ND alternator kit (with a
rebuilt alternator). The B&C cost 3 to 4 times more. Is it worth the cost? It
all depends on you opinion. Nothing wrong with spending the money but dont expect
100% reliability from the B&C, even on a dark and stormy night. Despite the
B&C advertisements, balanced rotor and all, there is no proof, data or facts
that the B&C system will achieve superior reliability over the stock ND alternator.
However if you are talking about reliability of a B&C or Stock ND alternator set-up
against certified 1950 and 60s technology factory aircraft electrical systems,
than yes, they are both way more reliable than the old certified stuff.
Now in theory may be B&C is better, but it cant be proven. The reason it cant be
proven is the data or statistics are not available. The reason for that is no
one is tracking it. Does B&C contact all customers with a service bulletin when
a problem is found? That would be nice. If you point to a ND alternator problem,
like the one above, than you can point to several B&C problems.
>Robert L. Nuckolls, III Wrote:
>Which only illustrates the ignorance of our customers promulgated by your rhetoric
and Van's equally ignorant advice.
Bob: I like to think they we have a different opinion not ignorant.
Quote: (snip) ignorance of our customers (snip) and Vans equally ignorant advice.
You just called everyone ignorant Bob. With all due respect that sounds condescending
and insulting. May be you meant something else, but I take umbrage to that.
No one likes to be called ignorant. Do you talk to Van.
I think your crow bar is great as a simple cheap solution to protecting alternators
with external regulators, which need protection, but not on IR alternators,
which is designed to work without any other OV protection.
Van recommends NOT installing an OV module on the 60amp ND alternator, because
it can and does cause damage to them. Bob's comment and use of the word *ignorance*
in describing Van's and Paul's opinion is dogmatic.
I don't know Van personally but I have met him and talked to him several times
over the last 15 years, building two of his kits. He is a very smart conservative
guy, and has a degree in engineering, as I do. From Van's stand point ND alternators
have been damaged with crow bar trips. Why did Bob call the man ignorant?
Whether intentional or accidental, a crow bar trip can damage an ND alternator.
This fact is bore out by the induced failure Jack had, described above.
We dont know what data Van is working on. The man after all has over 4200 planes
flying of his design and been in the kit plane market for 30 years, which gives
him a little creditability. To call his opinion or Paul's opinion ignorant
is not sensible. Everyone has the best intention here, and their suggestions
are safe and reasonable in my opinion, whether you or I agree or not.
I agree with Vans opinion that you should NOT use an OV module with an IR alternator,
but I also agree with Bob. If you feel that you cannot rely on an IR and
it's on-board OV protection than go with a crow-bar-ed external VR alternator.
An external VR adds complexity, wiring, cost and weight and scheduled maintenance
and testing, but it works.
I can accept the IR and the minimal risk alleged that there is a statistical possibility,
albeit unlikely, the field driver transistor can short. My decision
to use an IR alternator and no crow bar gives me a light, simple, compact, cheaper
system requiring no maintenance and testing. Plus parts are available nationwide
over the counter at thousands of auto part stores and auto electric shops.
Of course a NEW alternator is better than an overhauled one, but on a trip
if you did have a problem, you could buy one across the street from the airport
at Auto-parts-R-us, with a warranty. My old home airport had a large import
auto salvage yard with in walking distance from my hanger.
Therefore Van's advice is not ignorant or Pauls flavor of opinion less valid than
Bob's, technical minutia aside. Bob can't guarantee the crow bar will never
have a false trip or fail passively. He can't do it. Go ahead and say unlikely,
but never say never. Like wise, Nippon Denso can't guarantee a high voltage
failure, but ND engineers do know about OV. They understand OV and designed their
product to minimize the chance of it happening. From the field service history
in cars and experimental planes, ND did a great job. There are other alternator
brands, some better than others, but in my opinion the ND is probably
the best.
The ND alternator with an IR is designed as a stand-alone unit. The interaction
of and value of an OV module (crow bar) with an IR alternator is of dubious value.
If the OV module can never false trip, than you will never damage the alternator.
However that is not how it works in the real world. If Paul's B-lead
suppressor works than that might be an option, allowing a safer way to incorporate
a crow bar type device (Bob's or Paul's) safely on a ND alternator.
Adding a crow bar to an IR alternator is really an effort in belt and suspenders.
If you try to have your cake and eat-it to, you may end up with the worst of
both worlds. Dont mix and match systems. (Too much spice in one stew is bad.)
Accept the fact what ever you do, when you fly a plane, especially one you build
with systems you designed, you are risking life and limb NO MATTER WHAT YOU
DO. A single pilot in a single engine airplane is more risky than driving a car
crazy folks behind the wheel sharing the same road. I firmly believe you can
beat the General Aviation odds, but that might mean more pilot training, not
more electrical gadgets. The pilot is the most dangerous thing in the plane, not
the voltage regulator. Build your plane to fly with out it.
I think it is fair to disagree, right? I say go with an IR alternator with no extra
OV protection. My best advice is design your systems as simple as possible,
while still getting the job done. Have a back-up, but be reasonable.
Cheers George
---------------------------------
Stay connected, organized, and protected. Take the tour
Message 13
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| Subject: | Re: B&C website problems |
--> AeroElectric-List message posted by: gert <gert.v@sbcglobal.net>
did just that, sent them an emial with specifics, actually the whole
relay page seems to be fubar.
Robert L. Nuckolls, III wrote:
>--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
>
>At 03:48 PM 8/4/2005 -0500, you wrote:
>
>
>
>>--> AeroElectric-List message posted by: gert <gert.v@sbcglobal.net>
>>
>>hmmm
>>
>>no link anymore from 'lectric Bob's website to B&C ???
>>
>>B&C website, giving me errors when linking to products???
>>
>>something going on??
>>
>>
>
> We removed the link in preparation for some major changes
> coming to our website which will include some whippy new
> products.
>
> I've had a few "page not found" type errors when roaming
> the B&C site. It wouldn't hurt to drop them a note when
> you discover one.
>
> Bob . . .
>
>
>
>
--
is subject to a download and archival fee in the amount of $500
Message 14
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| Subject: | Screw terminals and Vision Microsystems' 1000 |
0.03 HTML_TEXT_AFTER_HTML BODY: HTML contains text after HTML close tag
0.06 HTML_TEXT_AFTER_BODY BODY: HTML contains text after BODY close tag
--> AeroElectric-List message posted by: "Malcolm Thomson" <mthomson@showmeproductions.com>
We are having reliability issues with a VMS 1000. Intermittent gauge
readings, reboots, etc. I believe the issue is the connections to the unit
which are made with screw terminals. These are the kind of terminals in
which you strip the wire, insert it into the hole and then tighten the screw
onto the wire. Does anyone have a suggestion of how this type of connection
can be turned into something more reliable. Have others had this issue with
the VMS 1000 or is it just me?
Thanks.
--
Message 15
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| Subject: | Electric Tail wheel tug |
--> AeroElectric-List message posted by: Gary Graham <beeb@pcez.com>
Salvage Co.: C&H Sales. California.
www.candhsales.com They have wheel chair motors and gear box etc. New and
used
Order a catalog A good read for the inventor
Pugsley the RV Dog
Message 16
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| Subject: | Re: The fatwire ground blues . . . |
--> AeroElectric-List message posted by: Guy Buchanan <bnn@nethere.com>
At 06:47 AM 8/4/2005, you wrote:
...
> The ideal ground system eliminates parallel
> pathways so that ANY open connection produces a passive
> failure.
Bob,
How would I test for parallel pathways? Could I simply disconnect
the big ground braid and look for continuity between the firewall forest of
tabs and the engine?
Thanks,
Guy Buchanan
K-IV 1200 / 582 / 99% done, thanks to Bob Ducar.
Do not archive
Message 17
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| Subject: | Re: Screw terminals and Vision |
Microsystems' 1000
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
Microsystems' 1000
At 07:59 PM 8/4/2005 -0600, you wrote:
>--> AeroElectric-List message posted by: "Malcolm Thomson"
><mthomson@showmeproductions.com>
>
>We are having reliability issues with a VMS 1000. Intermittent gauge
>readings, reboots, etc. I believe the issue is the connections to the unit
>which are made with screw terminals. These are the kind of terminals in
>which you strip the wire, insert it into the hole and then tighten the screw
>onto the wire. Does anyone have a suggestion of how this type of connection
>can be turned into something more reliable. Have others had this issue with
>the VMS 1000 or is it just me?
Funny thing about those terminal strips . . . Greg Richter
likes 'em too. See pages 41 and 50 of
http://www.aeroelectric.com/articles/richter/response_1.pdf
These terminal strips are one step above wrapping a wire
around a screw and mashing it under a washer. Not gas tight,
no insulation support.
I'm wondering if Greg uses these throughout is
EFIS system?
Anyhow, it does not surprise me that you or anyone else
might have some difficulties with them. They're not
very suited to a mobile environment, especially airplanes.
Bob . . .
Message 18
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| Subject: | Re: The fatwire ground blues . . . |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 08:33 PM 8/4/2005 -0700, you wrote:
>--> AeroElectric-List message posted by: Guy Buchanan <bnn@nethere.com>
>
>At 06:47 AM 8/4/2005, you wrote:
>
>...
> > The ideal ground system eliminates parallel
> > pathways so that ANY open connection produces a passive
> > failure.
>
>Bob,
> How would I test for parallel pathways? Could I simply disconnect
>the big ground braid and look for continuity between the firewall forest of
>tabs and the engine?
If you didn't install a parallel wired pathway, then it doesn't
need to be tested. In the case under discussion: In addition to
crankcase-to-ground-block fatwire, the system had a 22 or 20AWG ground wire
running from some case-grounded sensor on the engine to a ground
terminal on the instrument panel mounted display computer.
The fact that the sensor was ALREADY grounded to the engine made
the sensor groundwire a redundant parallel pathway that
burned when it tried to carry starter current through the
display when the fat-wire connection at the crankcase was
loose.
Just for grins, one COULD disconnect the fatwire from the
engine and measure resistance across the open gap. Under
ideal conditions, the measured value would be in kilo ohms.
Under worst case but acceptable conditions a reading of as
low as 100 ohms or so will be relatively risk free for
noise or burnt wire issues.
In the case cited above, the measurement would have been
under 2 ohms . . . an invitation for smoke.
Bob . . .
Message 19
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| Subject: | Power/ground terminal blocks |
--> AeroElectric-List message posted by: "Steve Ruse" <steve@wotelectronics.com>
I'm looking for power & ground terminal blocks, and haven't been able to
find them anywhere. I'm not sure if that is the correct term for what I am
looking for or not. Basically I need a terminal block that will connect
multiple wires to one wire, instead of acting as a pass-through/disconnect
point for each wire. I want to mount them behind my panel, bring in one hot
wire and one ground, and then feed each individual device from that strip.
Make sense?
I know something like this exists, I'm surprised they aren't easier to find.
Can anyone tell me where to get these?
Thanks!
Steve Ruse
Dallas, TX
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