Today's Message Index:
----------------------
1. 03:50 AM - Wiring of S704-1 with SD-8 OV protection (CarlRai@aol.com)
2. 04:26 AM - Re: Selective Radio Reception (Earl_Schroeder)
3. 07:13 AM - Built-in starter contactor (John Swartout)
4. 09:16 AM - Re: Built-in starter contactor (Robert L. Nuckolls, III)
5. 09:17 AM - Re: Wiring of S704-1 with SD-8 OV protection (Robert L. Nuckolls, III)
6. 09:37 AM - diode protect for single e-ignition Z-14? ()
7. 09:52 AM - Re: 40amp Denso Aerosport Alternator (Robert L. Nuckolls, III)
8. 10:04 AM - Voltage Regulator Failure? (D Wysong)
9. 10:11 AM - Re: Wiring of S704-1 with SD-8 OV protection (Ken)
10. 11:45 AM - Re: Wiring of S704-1 with SD-8 OV protection (CarlRai@aol.com)
11. 11:51 AM - Re: small high cca batteries (Ronald J. Parigoris)
12. 01:26 PM - Re: Re: battery maintainer More (Robert L. Nuckolls, III)
13. 01:46 PM - Re: small high cca batteries (Robert L. Nuckolls, III)
14. 02:48 PM - Re: small high cca batteries (Ronald J. Parigoris)
15. 02:51 PM - zinc-air batteries (Robert L. Nuckolls, III)
16. 04:59 PM - Re: Voltage Regulator Failure? (Robert L. Nuckolls, III)
17. 05:37 PM - Re: small high cca batteries (Robert L. Nuckolls, III)
18. 05:42 PM - Re: diode protect for single e-ignition (Robert L. Nuckolls, III)
19. 05:54 PM - Re: Selective Radio Reception (Fiveonepw@aol.com)
20. 07:41 PM - Re: small high cca batteries (Ken)
21. 07:41 PM - Re: small high cca batteries (Ronald J. Parigoris)
22. 08:07 PM - Fw: Europa-List: Voltage Regulator Problem? (D Wysong)
23. 08:14 PM - Antenna Locations (Tinne maha)
24. 08:31 PM - Re: Selective Radio Reception (Earl_Schroeder)
25. 08:47 PM - Re: Antenna Locations (Bob C.)
26. 08:50 PM - Re: 40amp Denso Aerosport Alternator ()
Message 1
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| Subject: | Wiring of S704-1 with SD-8 OV protection |
--> AeroElectric-List message posted by: CarlRai@aol.com
Bob and Listers,
Had planned to install wiring per Bob's Z-13 for a backup SD-8 alternator
with OV module across the coil of the power relay with the Aux Alternator switch
and 5A breaker on the ground lead of the coil.
B&C's drawing accompanying the components calls for a different installation
with the coil being switched to +14 on a 2A breaker.
Hmmmm, a bit of confusion is creeping into my less than 'lectrically literate
mind.....
Soliciting comments regarding the differences/advantages of each. Obviously
both will work fine but since I had already started wiring for Z-13, I hate to
change but can still make the revisions if necessary.
Carl Raichle
RV-9A - Closing in on it.....
Message 2
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| Subject: | Re: Selective Radio Reception |
--> AeroElectric-List message posted by: Earl_Schroeder <Earl_Schroeder@juno.com>
Hi Mark,
One possibility might be that your receiver is more 'selective' [narrow
band receiver] and the offending radios transmitters are slightly skewed
to one end of the transmitted frequency and is thus ignored. If you
could find another Microair to see if it also has this characteristic,
it would be helpful. Earl
Fiveonepw@aol.com wrote:
>--> AeroElectric-List message posted by: Fiveonepw@aol.com
>
>Howdy listers-
>
>Odd problem here- In communicating with dozens of other aircraft in the last
>year and a half, all report hearing me loud and clear, and I receive most of
>their transmissions just fine whether they are in the pattern with me or 50
>miles away.
>
>But there are TWO aircraft out of all of them that I can just barely hear-
>one (another RV) is broken and staticky, and another (a rental Cherokee where
>I'm based) I can't hear at all, just a slight change in background noise when
>they are transmitting. These two aircraft report they can hear me fine.
>Distance between and relative postion or orientation do not change this behavior.
>Other a/c and unicom report hearing both of us fine as well. My radio is
>Microair 760, bent whip bottom of fuse, and it doesn't matter whether I'm plugged
>direct to the radio or through a Softcomm portable intercom when I've got a
>co-pilot.
>
>Any ideas?
>
>Signed- Selective Reception in Columbia
>(Mark Phillips)
>
>
>
>
Message 3
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| Subject: | Built-in starter contactor |
--> AeroElectric-List message posted by: "John Swartout" <jgswartout@earthlink.net>
Bob, on May 9th you replied, in part, to jerry@mc.net:
What you describe will function electrically. If that system
is attractive to you, consider using the built-in starter contactor
that comes with most modern starters. Use the boost relay
circuit shown in Figure Z-22. Then jumper alternator b-lead
to the starter contactor hot terminal using a Maxi-Fuse HHX inline
holder. See page 13 of
of
http://www.bussmann.com/shared/library/catalogs/Buss_Auto-Fuse_Cat.pdf
Maxi fuses can be found on page 3. Use MAX60 fuse on 40A alternator,
MAX80 on a 60A alternator. Eliminate alternator loadmeter feature.
The boost relay can mount on firewall. No new hardware bolted
to engine.
Bob . . .
My Sky-Tec starter is said to "feature an integrated starter solenoid
for homebuilt applications not wishing to install a separate firewall
solenoid."
I assume a starter solenoid is the same thing as a starter contactor.
Can you discuss why one might choose to have another starter contactor
if the starter has one built in?
Thanks.
John
Message 4
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| Subject: | Re: Built-in starter contactor |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 10:11 AM 6/12/2005 -0400, you wrote:
>--> AeroElectric-List message posted by: "John Swartout"
><jgswartout@earthlink.net>
>
>Bob, on May 9th you replied, in part, to jerry@mc.net:
>
>
>What you describe will function electrically. If that system
> is attractive to you, consider using the built-in starter contactor
> that comes with most modern starters. Use the boost relay
> circuit shown in Figure Z-22. Then jumper alternator b-lead
> to the starter contactor hot terminal using a Maxi-Fuse HHX inline
> holder. See page 13 of
> of
>http://www.bussmann.com/shared/library/catalogs/Buss_Auto-Fuse_Cat.pdf
>
>
> Maxi fuses can be found on page 3. Use MAX60 fuse on 40A alternator,
> MAX80 on a 60A alternator. Eliminate alternator loadmeter feature.
> The boost relay can mount on firewall. No new hardware bolted
> to engine.
>
>
> Bob . . .
>
>
>My Sky-Tec starter is said to "feature an integrated starter solenoid
>for homebuilt applications not wishing to install a separate firewall
>solenoid."
>
>
>I assume a starter solenoid is the same thing as a starter contactor.
>Can you discuss why one might choose to have another starter contactor
>if the starter has one built in?
See http://aeroelectric.com/articles/strtctr.pdf
The extraordinary inrush currents common to modern starter
designs that caused extraordinary wear on the start switch
contacts of the ACS510 off-l-r-both-start keyswitch and
prompted an AD to add a diode across the contactor coil.
I prefer NOT to subject the ACS510 or any other panel mounted
switch to this stress and have recommended an auxiliary
starter contactor as illustrated in all of the Z-figures
-OR- use of a boost relay as depicted in figure Z-22 of
http://aeroelectric.com/articles/strtctr.pdf which not
only cures (1) a run-on problem with SOME PM starters when
using the on-board contactor (2) but isolates the panel
mounted starter control from the high current requirements
of the starter contactor.
By the way, if you ARE using a PM starter then figure
Z-22 may be the recommended control philosophy. Some of
these starters exhibit a delayed pinion engagement quirk
when back-emf during spin-down of the deenergized motor
keeps the pinion extended. These starters should be either
wired with ROBUST starter push buttons and heavier
than usual control wires (recommend 16AWG and 10A fuse)
-OR- per figure Z-22.
Bob . . .
Message 5
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| Subject: | Re: Wiring of S704-1 with SD-8 OV protection |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 06:47 AM 6/12/2005 -0400, you wrote:
>--> AeroElectric-List message posted by: CarlRai@aol.com
>
>Bob and Listers,
>
>Had planned to install wiring per Bob's Z-13 for a backup SD-8 alternator
>with OV module across the coil of the power relay with the Aux Alternator
>switch
>and 5A breaker on the ground lead of the coil.
>
>B&C's drawing accompanying the components calls for a different installation
>with the coil being switched to +14 on a 2A breaker.
>
>Hmmmm, a bit of confusion is creeping into my less than 'lectrically literate
>mind.....
>
>Soliciting comments regarding the differences/advantages of each. Obviously
>both will work fine but since I had already started wiring for Z-13, I
>hate to
>change but can still make the revisions if necessary.
The 5A breaker was called out as a lower cost, adequate protection
for this circuit. If you want to us a 2A or even a 1A breaker on
the SD-8 control, it's fine too. Actual operating current through
this breaker is about 0.1A
I chose to say with the 5A breaker as it was easier to find and
less expensive.
Bob . . .
Message 6
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| Subject: | diode protect for single e-ignition Z-14? |
--> AeroElectric-List message posted by: <psiegel@fuse.net>
Let's assume a single engine kitbuilt sportplane with a dual battery, dual alternator
(figure Z-14) system with one magneto and one electronic ignition system.
Each of the two batteries would have its own always hot battery bus.
It would seem to be a good idea to have a redundant supply of power to the single
electronic igniton system, one from each always hot battery bus.
Should the two batteries be isolated from the common supply to the single electronic
ignition system so that the only way to connect the two batteries together
is by the cross-feed contactor? If yes, how could this be accomplished?
Would a diode or a bridge rectifier between each always hot battery bus and the
single elctronic ignition accomplish this? Would a heat sink be needed on each
of these diodes? Should a specific diode be used? Or is there a better way?
Message 7
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| Subject: | 40amp Denso Aerosport Alternator |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 04:44 PM 6/11/2005 -0500, you wrote:
>--> AeroElectric-List message posted by: "Alex Peterson"
><alexpeterson@earthlink.net>
>
> > The 40 amps Denso is great and highly recommend it. No doubt similar to
> > the one niagarairparts.com sells. E-mail the part number to me and I can
> > get you detailed info. All the modern Denso have an IC chip voltage
> > regulator (VR) that controls voltage and protects against over voltage
> > (OV). You have choices:
> >
> >
> > 1) Use the alternator with internal VR as per the installation instruction
> > (if you dont have them see niagaraairparts.com).
>
>George, excellent post. There must be at least 500 messages on this list
>talking about overvoltage and alternators. One question that remains
>unanswered is this: If an alternator runs away voltage wise, but is still
>connected to the battery, how many amps would the battery draw at the point
>when the voltage is harmfully high? Isn't there some inherent protection in
>having a circuit breaker in the main alternator output line? For example, I
>have a 50 amp breaker on my 40 amp alternator.
>
>Alex Peterson
>RV6-A N66AP 624 hours
>Maple Grove, MN
Good question. Last spring I tried to get some dialong going
based on repeatable experiments concerning the dynamics and
functionality of crowbar ov protection. I began a series
of bench demonstrations of the simple ideas that support the
philosophy and published a running discussion document which
was last posted as revision C at:
http://www.aeroelectric.com/articles/Crowbar_OV_Protection/DC_Power_System_Dynamics_C.pdf
The last experiment was to scale the magnitude of the
exactly the problem you asked about. I'll refer you to
the last few pages of the document.
Bottom line is that with a well maintained battery of
ANY type, an ov condition is not an event that requires
hair-trigger, millisecond response for correction.
Classically, we've designed fast responding systems
because (1) it wasn't hard to do, (2) it made the
customer feel better about it and (3) it offset the
unknowns concerning battery condition. We KNOW that
majority of all batteries flying in SE airplanes don't
get replaced until they don't crank the engine any
more . . . maybe even for the 3rd or 4th time!
Since you choose to understand how important the
battery is in minimizing risk and maximizing performance,
then YOUR battery is going to be replaced long before
it ceases to be an effective guard at the gates to
electrical disaster. Super fast response to an OV
condition is not at all critical to the health and
well-being of your electro-whizzies qualified to DO-160.
A new paradigm offering electrical system performance
bounded between 0 and 18 volts has been proposed and
I presume work to perfect systems based on this
philosophy is moving forward. If you're interested in
incorporating this philosophy, then the battery is
no longer qualified to guard the gate . . . I presume
folks developing this system will take this into
account and include mitigating systems into the
design.
Bob . . .
Message 8
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| Subject: | Voltage Regulator Failure? |
--> AeroElectric-List message posted by: D Wysong <hdwysong@gmail.com>
This was posted on the Europa list (Rotax specific) but I figured it
might get some comments from you folks. Any ideas?
D
---------- Forwarded message ----------
From: David Joyce <davidjoyce@doctors.org.uk>
Subject: Europa-List: Voltage Regulator Failure
Just back from a great Europa Baltics trip, splendidly organised by Bob
Harrison & Ivor Phillips, and accompanied by challenging weather, and a
problem of intermittent charge, developing on the last leg home. The ammeter
would show a discharge related to however many items I had switched on, for
anything up to 40 mins and then have a spell of rapid recharging, gradually
coming back to zero, suggesting a fully recharged battery. Incidentally the
40 min bit coincided with the Channel crossing , which with a 914 made us
sit up and take notice!
I remember reading accounts of failing regulators previously but
paid less attention than I should have done! Is this intermittent failure
to charge the sort of symptom to be expected?
Happy landings, David Joyce, G-XSDJ
Message 9
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| Subject: | Re: Wiring of S704-1 with SD-8 OV protection |
--> AeroElectric-List message posted by: Ken <klehman@albedo.net>
Carl
Regarding the position of the circuit breaker which I think you were
also enquiring about:
It should function fine on the positive or ground side of the coil.
There is no particular risk of running a small wire from the negative
terminal of the coil to the circuit breaker because a short in that wire
would still only flow well under an amp as limited by the coil.
Since there is always a slight risk of the coil shorting to ground
internally I can see why someone might prefer the breaker on the
positive side of the coil. Perhaps even more so for other situations
using a hot running metal encased contactor. With Z-13 you could always
use a small wire (22awg ?) to jumper to the positive coil terminal and
act as an additional fusible link if that is a concern.
In practice you might find it more difficult and risky to run a wire
from the battery to a circuit breaker and then on to the relay in
question. Z-13 seems like an elegant alternative to that.
Ken
CarlRai@aol.com wrote:
>--> AeroElectric-List message posted by: CarlRai@aol.com
>
>Bob and Listers,
>
>Had planned to install wiring per Bob's Z-13 for a backup SD-8 alternator
>with OV module across the coil of the power relay with the Aux Alternator switch
>and 5A breaker on the ground lead of the coil.
>
>B&C's drawing accompanying the components calls for a different installation
>with the coil being switched to +14 on a 2A breaker.
>
>Hmmmm, a bit of confusion is creeping into my less than 'lectrically literate
>mind.....
>
>Soliciting comments regarding the differences/advantages of each. Obviously
>both will work fine but since I had already started wiring for Z-13, I hate to
>change but can still make the revisions if necessary.
>
>Carl Raichle
>RV-9A - Closing in on it.....
>
>
Message 10
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| Subject: | Re: Wiring of S704-1 with SD-8 OV protection |
--> AeroElectric-List message posted by: CarlRai@aol.com
Thanks to both Bob and Ken for your comments.
I'm sticking with Z-13......
Off to the shop with wirestripper and crimper in hand.
Carl
Message 11
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| Subject: | Re: small high cca batteries |
--> AeroElectric-List message posted by: "Ronald J. Parigoris" <rparigor@suffolk.lib.ny.us>
Is anyone flying with a ATP Ultrabat-13?
I am thinking to use with Rotax 914.
http://www.aircraftspruce.com/catalog/elpages/atphighpwr.php
http://www.recreationalmobility.com/cgi-bin/recreation/27923.html
Is the expected service life similar to a Odyssey 680?
thx.
Ron Parigoris
N4211W
Europa Monowheel
Message 12
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| Subject: | Re: battery maintainer More |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 09:18 AM 6/11/2005 -0500, you wrote:
>--> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
><nuckollsr@cox.net>
>
>At 06:28 PM 6/10/2005 -0500, you wrote:
>
> >--> AeroElectric-List message posted by: "David Carter"
> ><dcarter@datarecall.net>
> >
> >As previously stated, I have a Schumcher and have reported that it applies a
> >gradually increasing charging voltage until it hits 14.4 or so, then shuts
> >OFF and lets battery self-discharge to 12.99 (13) v at which time it starts
> >another charging cycle.
> > - With a fully charged battery, it takes about 1 second to go from
> 13 to
> >14.4 v and maybe 15 minutes to much longer to self-discharge down to 13 v
> >again.
> > - With a discharged battery, it will hang in the 13.5 v area for a
> long
> >time (at either 2 amps or 10 amps, selectable, with 10 amps being for faster
> >recharge of a discharged battery), gradually increasing top 14.4 v again -
> >may take 15 minutes, may take 30 minutes, may take an hour, but as the
> >battery takes more charge, the cycle time decreases until it is "on 1
> >second" and "off for a long time".
> > - I put the digital VOM on the two alligator clips on the battery
> >terminals and sit and sip lemonade while watching the charger do its thing -
> >I've gone thru 2 (still on my 2nd) - when it quits performing as I've
> >described, the charger is broken or the battery is bad.
>
> I think this was the protocol option for smart-chargers before
> microprocessors came along. And . . . it's an effective protocol
> that does a good job of charging/maintaining a battery.
>
> >It looks to me like the reported numbers that started this current "thread"
> >were taken at random times, without any regard to where the charger and
> >battery were in "the cycle of charge & discharge". So, I don't think the
> >comment about "Hmmmm . . . doesn't like like this critter goes into much of
> >a maintenance mode . . . endpoint voltage is less than the float voltage of
> >a fully charged battery. Further, we don't know if it went into a top-off
> >mode by pulling
> >the battery up to better than 14 volts." reflects knowledge of the
> >Schumacher performance
> > - there is no "maintenance mode" - it shuts OFF - NO voltage, until it
> >starts pumping current thru again at 13v up to 14.4.
> >
> >Just trying again to shed some light on how this charger works. Everytime
> >I've commented in the past it seems to have gone unnoticed and
> >un-acknowledged.
>
> The numbers I've cited for my experiments were continuously monitored
> (and plotted) and taken from manufacturer's statements for protocols.
> The current crop of battery charger/maintainers are a lot more agile.
>
> I'm finding that Schumacher has DIFFERENT protocols. For example,
> the recharge cycle depicted at:
>
>http://www.aeroelectric.com/Pictures/schumacher_2.jpg
>
> is strikingly different than this one:
>
>http://www.aeroelectric.com/Pictures/schumacher_3.jpg
>
> The earlier trace was taken from the charge/maintenance
> protocol for a WM-1562A that I'd mentioned in an earlier
> thread. I bought this at Walmart for $18. Folks reported
> not being able to find them at their local stores (although
> mine still has a half dozen). Last night I picked up its
> bigger brother for $25. Much more "smarts" (push-buttons
> and lights) and higher recharge capability (6A max).
>
> This was the WM-600A. I'm doing some further experiments
> with it now and will report the results as they become
> available.
>
> You raise an interesting question that is not obviously
> deducible from the plots taken so far . . . does the
> "maintenance" mode ACTIVELY support the battery just above
> its open circuit voltage -OR- does the charger simply shut
> off and wait for the battery to self-discharge to the
> point where protocol demands action from the charger
> to replace lost energy. I'll find out for the two
> Schumacher devices I have on hand.
I discharged one of my biggest portable power source batteries
(a 33 a.h. Panasonic) and put the WM600 Charger on it and
monitored voltage vs. time with the CBA-II analyzer. A couple
of hours after the charger reported "fully charged" I measured
current exchange from charter to battery and it was zero. I added
some artificial self-discharge leakage in the form of a 10
ohm power resistor and let it run for a few hours whereupon
I collected the following data:
http://www.aeroelectric.com/articles/Battery_Maintenance/WMA-600_Chg_Maint_Test_1.gif
One can see that this charger is strikingly different from
the WMA-1562 discussed earlier. This charger has a 1 hour
top-off mode at 15 volts before it shuts down completely.
When I added the sever case of self discharge leakage, the
charger comes alive at 12.7 volts and recharges the battery
with the same 1-hour top-off protocol. This cycle repeats
as the battery voltage again drops below 12.7 volts.
What we've learned so far: There is no fixed protocol shared
by the two Schumacher chargers tested and we've confirmed
David's observation that the charger doesn't support the
charged battery at some maintenance voltage level but simply
shuts off to wait for discharge serious enough to warrant
recharging.
I'll go see what the WMA-1562 charger does . . .
Oh, by the way . . . maintenance current out of the Battery
Tenders I have is not zero . . . it's on the order of 1.5
milliamperes for an array of SVLA batteries being stored
in parallel. I'll get a voltmeter reading for the array
while on charge and then disconnect the charger to see if
the votlage falls.
Bob . . .
Message 13
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| Subject: | Re: small high cca batteries |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 02:47 PM 6/12/2005 -0400, you wrote:
>--> AeroElectric-List message posted by: "Ronald J. Parigoris"
><rparigor@suffolk.lib.ny.us>
>
>Is anyone flying with a ATP Ultrabat-13?
>
>I am thinking to use with Rotax 914.
>
>http://www.aircraftspruce.com/catalog/elpages/atphighpwr.php
>
>http://www.recreationalmobility.com/cgi-bin/recreation/27923.html
These are "premium" batteries. By that I mean that
they are relatively expensive compared to other
very popular and lower cost products. If you're
truly weight restricted, then perhaps the weight
savings of about 11 pounds between the garden variety
17 a.h. product ($40-$60) and the Ultra-Start Red
($92) offers a positive perception of return on
investment. If you're going with the Ultra-Bat 13,
then you save only 6 pounds for an expenditure of
$129 (and delta-dollars of 60-80).
Do you plan to replace based on (1) cap checks or
(2) preflight cranking tests? If (1), you'll
have to acquire test equipment and spend $time$
to check the battery that will only add to the
cost of ownership. If (2), I would encourage
you to run the Ultra-Bat until it craps, then replace
it with a Panasonic LC-1218. When that battery craps,
do another cycle with a second Ultra-Bat and then
a second Panasonic. Report back to us in a few years
the results of your tests because you'll then know
more about this product than anyone else does
at the present time.
>Is the expected service life similar to a Odyssey 680?
What do you mean by "service life"? If you have no
endurance requirements other than to be able to
crank the engine, this battery should perform as well
as any other SVLA product for it's size.
Nobody is going to be able to offer comparative data
for the two products until they've taken data that
makes the comparison under similar if not identical
conditions. I would not expect this kind of data to
come from the GA user community unless YOU conduct
the tests cited above and record results. You may
get testimonials both pro and con citing things like
"been use'n the thing for 5 years and still cranks
my engine great!" or, "a friend of my cousin has
a brother-in-law who tried one in his GoFast7 and
it crapped in a couple of months. Wouldn't put that
piece of junk in my lawnmower."
Neither data point has value in deducing a meaningful
answer to your question. I'll suggest the most important
question for you to ask is whether these products will
offer a lower cost of ownership and hence better return
on investment than the alternatives.
Bob . . .
Message 14
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| Subject: | Re: small high cca batteries |
--> AeroElectric-List message posted by: "Ronald J. Parigoris" <rparigor@suffolk.lib.ny.us>
Hello Bob
I could not find any info when I searched Panasonic LC-1218? Any helpful info where
I may
find?
The full picture is we are building a Europa Monowheel with Rotax 914 and Airmaster
Prop.
We have the internal minimal Rotax alternator, and a Flight Crafters (Denso?)
that will
be mounted on the vacuum pad. Supposedly a realistic 2 plus times output of Rotax.
We
were thinking we could use the 13 amp battery with the Denso, and perhaps the ultra
start
red 5 amp battery for the rotax alternator.
We have both glider wings, and short wings. When you install the glider wings,
things go a
bit more nose heavy. We figured we could have 2 locations for the 5 amp battery
to adjust
CG.
Reasoning was the 2 batteries would be bout same weight as normal used 1 battery.
Reasoning was to have ability to connect 2 batteries for a start if needed. Would
probably
replace no matter after 4 years or so, or if had a problem.
Have a few questions:
1) Is there any problem connecting 2 batteries, each having its own alternator
for a short
time, like to start? We were thinking of using a Marine style switch as a isolator,
connection for each battery to its side of things and also ability to connect to
each
other.
2) In the event lets say the Denso alternator failed, is there a problem connecting
the 2
systems so you can use minimal stuff on that side? Can you just connect the 2 sides
or do
you need some sort of?? When throwing the switch should motor be at low RPMs to
prevent
some sort of frightful event?
3) If the 2 sides are just connected, is the only downside that the alternator
with the
higher voltage will take the full load?
4) Do you hate the idea of using a big switch instead of a relay or solenoid?
Thx.
Sincerely
Ron Parigoris
Message 15
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| Subject: | zinc-air batteries |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
A few weeks ago, Eric Jones sent me a 9v "zinc-air" battery
which I tested on the CBA-II analyzer and plotted its performance
against the garden variety alkaline cells. See plot at:
http://www.aeroelectric.com/articles/Batteries/9V_ZincAir_Comparison.gif
There are plots of alkaline cells discharged at 100 mA and
20 mA along with a plot of the zinc-air cell discharged at
20 mA. The zinc air delivers at a somewhat lower average voltage
but for more than 2 twice the time for the alkaline cells discharged
at the same rate. Just for grins, I'll pick up some good-ol "heavy
duty" carbon-zinc cells and add them to the plot.
In any case, know that the Z-A 9V packs about twice the energy
of its nearest cousins but only IF you discharge them at a modest
rate (.02A or less).
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 16
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| Subject: | Re: Voltage Regulator Failure? |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 12:02 PM 6/12/2005 -0500, you wrote:
>--> AeroElectric-List message posted by: D Wysong <hdwysong@gmail.com>
>
>This was posted on the Europa list (Rotax specific) but I figured it
>might get some comments from you folks. Any ideas?
>
>D
>
>---------- Forwarded message ----------
>From: David Joyce <davidjoyce@doctors.org.uk>
>Date: Jun 12, 2005 6:56 AM
>Subject: Europa-List: Voltage Regulator Failure
>To: Europa list <europa-list@matronics.com>
>
>Just back from a great Europa Baltics trip, splendidly organised by Bob
>Harrison & Ivor Phillips, and accompanied by challenging weather, and a
>problem of intermittent charge, developing on the last leg home. The ammeter
>would show a discharge related to however many items I had switched on, for
>anything up to 40 mins and then have a spell of rapid recharging, gradually
>coming back to zero, suggesting a fully recharged battery. Incidentally the
>40 min bit coincided with the Channel crossing , which with a 914 made us
>sit up and take notice!
> I remember reading accounts of failing regulators previously but
>paid less attention than I should have done! Is this intermittent failure
>to charge the sort of symptom to be expected?
The charging system could become intermittent either because
of some condition inside the regulator/rectifier -OR- wiring
external to the regulator that carries output power or control
signals to the regulator.
Sounds like it's consistent enough to instrument and go catch
the problem during a test flight. I'd look at AC voltage into
the regulator, DC voltage out of the regulator, control voltage(s)
to the regulator and bus voltage in addition to what appears
to be the battery ammeter.
Observations taken on these readings during a 'brown out' will
be important clues as to how one would proceed.
Bob . . .
Message 17
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| Subject: | Re: small high cca batteries |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 05:43 PM 6/12/2005 -0400, you wrote:
>--> AeroElectric-List message posted by: "Ronald J. Parigoris"
><rparigor@suffolk.lib.ny.us>
>
>Hello Bob
>
>I could not find any info when I searched Panasonic LC-1218? Any helpful
>info where I may
>find?
I've got Panasonic and EnerSys (Hawker) data posted at:
http://www.aeroelectric.com/Mfgr_Data/Batteries
I note that the ATP 13 a.h. battery bears a sriking
resemblance to the EnerSys Genesis G13 found on page
13 of
http://www.aeroelectric.com/Mfgr_Data/Batteries/Enersys_Hawker/Genesis.pdf
>The full picture is we are building a Europa Monowheel with Rotax 914 and
>Airmaster Prop.
>We have the internal minimal Rotax alternator, and a Flight Crafters
>(Denso?) that will
>be mounted on the vacuum pad. Supposedly a realistic 2 plus times output
>of Rotax. We
>were thinking we could use the 13 amp battery with the Denso, and perhaps
>the ultra start
>red 5 amp battery for the rotax alternator.
>
>We have both glider wings, and short wings. When you install the glider
>wings, things go a
>bit more nose heavy. We figured we could have 2 locations for the 5 amp
>battery to adjust
>CG.
>
>Reasoning was the 2 batteries would be bout same weight as normal used 1
>battery.
>
>Reasoning was to have ability to connect 2 batteries for a start if
>needed. Would probably
>replace no matter after 4 years or so, or if had a problem.
The single 13 (or 17) will start the engine nicely.
"4 years or so" is not very definitive . . . with two
alternators let's assume you'll run 'em until they
don't crank the engine any more.
>Have a few questions:
>
>1) Is there any problem connecting 2 batteries, each having its own
>alternator for a short
>time, like to start? We were thinking of using a Marine style switch as a
>isolator,
>connection for each battery to its side of things and also ability to
>connect to each
>other.
>
>2) In the event lets say the Denso alternator failed, is there a problem
>connecting the 2
>systems so you can use minimal stuff on that side? Can you just connect
>the 2 sides or do
>you need some sort of?? When throwing the switch should motor be at low
>RPMs to prevent
>some sort of frightful event?
I'd run one big battery with the larger alternator and
use it to crank the engine. Use a smaller battery with
the smaller alternator and close the crossfeed relay
(S704 instead of S701) to share power between sides only
if one alternator has died.
>3) If the 2 sides are just connected, is the only downside that the
>alternator with the
>higher voltage will take the full load?
generally . . . but the only reason to connect both sides is
if one alternator has quit.
>4) Do you hate the idea of using a big switch instead of a relay or solenoid?
Sure. Thats fine too. You're needing a min-version of
Z-14.
But these are considerations above and beyond the points
I offered in my last post. The batteries you cited were
pretty expensive . . . and if you plan to run them 'til
they die, then you don't need a $time$ consuming maintenance
program to assure system integrity.
You're needing a battery that will crank for the big one.
Anything over 12 a.h. in a variety of products will do that
job. You need a small battery to stabilize the smaller
system, anything from 6 a.h. and up would do and it doesn't
have to supply cranking power so make it small, light and
wire up with relatively small wires.
The $high$ batteries you originally proposed would be
fine but I think you can do MUCH better than buying
from Aircraft Spruce. See Digikey catalog page at:
http://www.aeroelectric.com/Mfgr_Data/Batteries/Panasonic/Digikey_P1414.pdf
check out catalog numbers P174 and P218
Bob . . .
Message 18
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| Subject: | Re: diode protect for single e-ignition |
Z-14?
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
Z-14?
At 12:31 PM 6/12/2005 -0400, you wrote:
>--> AeroElectric-List message posted by: <psiegel@fuse.net>
>
>
> Let's assume a single engine kitbuilt sportplane with a dual battery,
> dual alternator (figure Z-14) system with one magneto and one electronic
> ignition system. Each of the two batteries would have its own always hot
> battery bus.
>
> It would seem to be a good idea to have a redundant supply of power to
> the single electronic igniton system, one from each always hot battery bus.
You've already got two independent ignition systems . . .
> Should the two batteries be isolated from the common supply to the
> single electronic ignition system so that the only way to connect the two
> batteries together is by the cross-feed contactor? If yes, how could
> this be accomplished?
>
> Would a diode or a bridge rectifier between each always hot battery bus
> and the single elctronic ignition accomplish this? Would a heat sink be
> needed on each of these diodes? Should a specific diode be used? Or is
> there a better way?
Figure Z-19 shows a diode isolated two-battery feed
for an engine absolutely dependent on DC power to run.
See:
http://www.aeroelectric.com/PPS/Architecture_PDF/Z19K_1.pdf
http://www.aeroelectric.com/PPS/Architecture_PDF/Z19K_2.pdf
You can do as you suggest but I cannot see that it adds
any value and only increases complexity.
Bob. . .
Message 19
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| Subject: | Re: Selective Radio Reception |
--> AeroElectric-List message posted by: Fiveonepw@aol.com
One possibility might be that your receiver is more 'selective' [narrow
band receiver] and the offending radios transmitters are slightly skewed
to one end of the transmitted frequency and is thus ignored.
>>>>>>>>>
Hi Earl- thanks for the response-
Interesting suggestion- any idea if these radios (or others, for that matter)
are "tunable" if it is off-freq a bit one way or the other? Any theories if
SWR could effect this, or is that just xmit relevant?
Thanks again-
Mark
Message 20
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| Subject: | Re: small high cca batteries |
--> AeroElectric-List message posted by: Ken <klehman@albedo.net>
Hi Ron
FWIW I went through a similar battery search about a year ago and
settled on two Deka Powersport ETX9 batteries at about 9 AH each and
about 8 lb each. They are priced in between the red tops and the
panasonics and I suspect are in between them in quality but they were
available locally from the Deka outlet, the local farm supply, and
motorcycle shops.
http://www.eastpenn-deka.com/products/small_engine_power.html
Ken
Ronald J. Parigoris wrote:
>--> AeroElectric-List message posted by: "Ronald J. Parigoris" <rparigor@suffolk.lib.ny.us>
>
>Hello Bob
>
>I could not find any info when I searched Panasonic LC-1218? Any helpful info
where I may
>find?
>
>
snip
Message 21
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| Subject: | Re: small high cca batteries |
--> AeroElectric-List message posted by: "Ronald J. Parigoris" <rparigor@suffolk.lib.ny.us>
Hello Bob
"I'd run one big battery with the larger alternator and
use it to crank the engine. Use a smaller battery with
the smaller alternator and close the crossfeed relay
(S704 instead of S701) to share power between sides only
if one alternator has died."
Which diagram are you referring S704 and S701?
>3) If the 2 sides are just connected, is the only downside that the
>alternator with the
>higher voltage will take the full load?
"generally . . . but the only reason to connect both sides is
if one alternator has quit."
If the larger battery is a bit run down, or in bad condition and I put the smaller
one in
parallel to help a start up, would this be a bad thing?
If I run the radios and instruments on the smaller battery, if they were turned
on when
starting the motor off the larger battery only, is there any downside to doing
this?
Thx.
Sincerely
Ron Parigoris
N4211W
Europa XS Monowheel
Message 22
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| Subject: | Fwd: Europa-List: Voltage Regulator Problem? |
--> AeroElectric-List message posted by: D Wysong <hdwysong@gmail.com>
Here's another, Bob!
--> Europa-List message posted by: MJKTuck@cs.com
Hi Folks,
The last two or three times I have gone flying I have experienced a problem
with the 5A ALT FIELD circuit breaker popping. The solution at first seemed
easy just push it back in and all is well. It occurs usually at start up soon
after I turn on the radio panel circuit.
A couple of flights ago it popped a couple more times in the cruise and I
reset it with no further problems.
Yesterday however it popped quite a number of times (5 or 6) and only settled
down after I had turned the radio master off and back on again. I don't see
how turning the radios off would affect the ALT circuit breaker except I
suppose they use the most load.
Looking at the circuit the breaker is located between output C on the voltage
regulator and the main power bus (and thus the battery positive). Very
simple.
The only thing I can think of is that the voltage regulator is spiking at
more than 5 amps until it 'warms up' or reaches some kind of battery charged
point after the battery has been used after start (although the engine typically
fires after just a few turns).
Any ideas and/or solutions as to what the problem might be would be
appreciated. I would like to trouble shoot before replacing the
regulator but do not
want to remove the panel unless I really have to.
P.S I usually turn on (both) the split master/alt switch - perhaps I should
only turn on the alternator after engine start? I have close to 200 hours
flying time on the aircraft so again this is a doubtful cause.
Regards,
Martin Tuck
Europa N152MT
Wichita, Kansas
Message 23
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| Subject: | Antenna Locations |
--> AeroElectric-List message posted by: "Tinne maha" <tinnemaha@hotmail.com>
Bob/List,
I have mounted my trasponder & comm antennas on the bottom of my fueselage
21 inches apart. A source of unknown authority (i.e. the kit manufacturer)
has advised that I need to separate the two by a greater distance for fear
of comm interference from the trasponder. My source neglected to specify a
minimum distance. Will you please advise?
King KT-76A Transponder with a Garmin GNC 250-XL GPS Comm.
Thanks,
Grant
PS: The GPS antenna is on top of the fuselage about 1/2 mile from any other
antenna per Garmin's instructions.
Message 24
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| Subject: | Re: Selective Radio Reception |
--> AeroElectric-List message posted by: Earl_Schroeder <Earl_Schroeder@juno.com>
Hi Mark,
I believe the newer com radios are more difficult to 'adjust' [by a
Class I FCC type] than the older but then the older tend to wander more
than the new and need it. Of course, the requirement for more tunable
channels has caused tighter tolerances in the newer radios. Since
others can hear the offending transmitters OK, I doubt if SWR has much
impact in this situation. And yes, it is more .xmit relevant'. We
would be interested in hearing the solution if/when you discover it. Earl
Fiveonepw@aol.com wrote:
>--> AeroElectric-List message posted by: Fiveonepw@aol.com
>
>
>One possibility might be that your receiver is more 'selective' [narrow
>band receiver] and the offending radios transmitters are slightly skewed
>to one end of the transmitted frequency and is thus ignored.
>
>
>
>Hi Earl- thanks for the response-
>
>Interesting suggestion- any idea if these radios (or others, for that matter)
>are "tunable" if it is off-freq a bit one way or the other? Any theories if
>SWR could effect this, or is that just xmit relevant?
>
>Thanks again-
>Mark
>
>
>
>
Message 25
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| Subject: | Re: Antenna Locations |
--> AeroElectric-List message posted by: "Bob C. " <flyboy.bob@gmail.com>
Grant
The two operate a vastly different frequencies and modes . . . I doubt you
will have a problem. If you have them mounted I'd sure try it before I got
too excited!
Good Luck,
Bob Christensen - RV8 Builder - SE Iowa
On 6/12/05, Tinne maha <tinnemaha@hotmail.com> wrote:
>
> --> AeroElectric-List message posted by: "Tinne maha" <
> tinnemaha@hotmail.com>
>
> Bob/List,
>
> I have mounted my trasponder & comm antennas on the bottom of my fueselage
> 21 inches apart. A source of unknown authority (i.e. the kit manufacturer)
> has advised that I need to separate the two by a greater distance for fear
> of comm interference from the trasponder. My source neglected to specify a
> minimum distance. Will you please advise?
>
> King KT-76A Transponder with a Garmin GNC 250-XL GPS Comm.
>
> Thanks,
> Grant
>
> PS: The GPS antenna is on top of the fuselage about 1/2 mile from any
> other
> antenna per Garmin's instructions.
>
>
Message 26
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| Subject: | Re: 40amp Denso Aerosport Alternator |
--> AeroElectric-List message posted by: <gmcjetpilot@yahoo.com>
>If an alternator runs away voltage wise, but is still connected to the battery,
how many amps >would the battery draw at the point when the voltage is harmfully
high? Isn't there some >inherent protection in having a circuit breaker
in the main alternator output line? For example, >I have a 50-amp breaker on
my 40 amp alternator.
>Alex Peterson
>RV6-A N66AP 624 hours
>Maple Grove, MN
Hello Alex:
No I don't think that's going to work that way. The answer I believe is volts and
amps are obviously different, and the circuit breaker works on current (amps)
not voltage. Actually the CB is a thermal device and needs current (flow) to
heat up and trip.
If the volts go up, the battery will absorb so much and than, the system buss volts
will climb and the amps may even drop due to Ohms law:
Power = Volts x Amps,
Pwr (constant) = Volts(up) x Amps(down)
Bob N. could address this better than I but think Im in the ball-park.
I also have a 50 amp CB on my b-lead (40 amp alternator). I had a short lived idea
about putting a "crow-bar" on this 50 amp CB for the b-lead, to force it to
trip (open, pop), just like Bob's crow bar on the voltage regulator CB. The
big differnce is the CB on the VR is 5 amps and the b-lead CB we have is 50 amps.
I decided against it.
You can always reach over and manually pull the CB yourself if needed. May be one
advantage of using a CB on the alternator vs. a fuse.
A crow bar (SCR, silicon control rectifier) would be very large to "pop" a 50 amp
CB, but I am staying with my original position of not adding on any extra OV
protection to an internally regulated alternator based on the unlikely chance
of OV.
The problem with a 50 amp CB is it might take 600% (300 amps) to cause it to trip,
which might take .36-1 seconds. That might be too slow to help the radios.
which is the theory of doing the OV protection in the first place. They make
high amp SCR's that can take 300-500 amps for a second might be possible but too
much to be practical (safe).
If I wanted a b-lead disconnect, I would use a solid state relay to open the circuit
directly, with out using dead short (crow-bar). With the crow bar you hope
the CB trips fast enough to do good and fast enough before the crow bar melts.
May be Bob N. could give us insight into why a 50amp crow bar would not work or
would not want to do this. Again I am in the KISS camp, use the internal VR alternators
OV protection as is and leave all the extras off.
Cheers George (BTW Nice web site Alex)
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