Today's Message Index:
----------------------
0. 12:20 AM - Make Sure You're Listed! List of Contributors Published in December! (Matt Dralle)
1. 05:24 AM - Re: alternator / generator (Cherie&Ken)
2. 06:07 AM - Re: alternator / generator (user9253)
3. 07:04 AM - Re: alternator / generator (rayj)
4. 07:28 AM - Re: Re: alternator / generator (Ken Ryan)
5. 07:38 AM - Re: RS422 - RS232 (donjohnston)
6. 07:40 AM - Re: alternator / generator (Ken Ryan)
7. 08:32 AM - Re: alternator / generator (rayj)
8. 08:45 AM - Re: alternator / generator (Robert L. Nuckolls, III)
9. 08:58 AM - Re: lithium facts (Rick Beebe)
10. 09:02 AM - Re: Re: alternator / generator (Robert L. Nuckolls, III)
11. 09:03 AM - Re: alternator / generator (Ken Ryan)
12. 09:11 AM - Re: alternator / generator (Robert L. Nuckolls, III)
13. 09:13 AM - Re: alternator / generator (Robert L. Nuckolls, III)
14. 10:16 AM - Re: alternator / generator (user9253)
15. 10:18 AM - Re: alternator / generator (Robert L. Nuckolls, III)
16. 10:34 AM - Re: Re: alternator / generator (Ken Ryan)
17. 10:48 AM - Re: alternator / generator (Ken Ryan)
18. 11:09 AM - Excellent value in test equipment . . . (Robert L. Nuckolls, III)
19. 11:29 AM - Re: lithium facts (ARGOLDMAN@aol.com)
20. 11:58 AM - Aerobatic wiring schematic (Ryan)
21. 01:30 PM - Re: lithium facts (Rick Beebe)
22. 04:32 PM - RS422 - RS232 (James Bean)
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Subject: | Make Sure You're Listed! List of Contributors Published |
in December!
Dear Listers,
The List of Contributors (LOC) is just around the corner! In December I post a
list of everyone that so generously made a Contribution to support the Lists.
Its my way of publicly thanking everyone that took a minute to show their appreciation
for the Lists.
Won't you take minute and assure that your name is on the upcoming LOC? Tell others
that you appreciate the Lists. Making a Contribution to support the Lists
is fast and easy using your Visa, MasterCard, or Paypal account:
http://www.matronics.com/contribution
Or, drop a personal check in the mail to:
Matt Dralle / Matronics
581 Jeannie Way
Livermore CA 94550
USA
I would like to thank everyone that has so generously made a Contribution thus
far during this year's List Fund Raiser! Remember that its YOUR support that
keeps these Lists running and improving! Don't forget to include a little comment
about how the Lists have helped you!
Thank you!
Matt Dralle
Matronics Email List Administrator
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Subject: | Re: alternator / generator |
Yes (probably)
If you have the external alternator connect it to a battery and measure
the standby current for a definitive answer.
Most vehicles leave the alternator connected 24/7 and they usually draw
an acceptable couple of mA drain. Sounds like that is the case for your
unit although I also have been appalled by the documentation
accompanying equipment from "major manufacturers" so I would not put a
lot of money on it.
For example the 40A IR Nippondenso that I use was only installed on non
road equipment and it draws 2 Amps with the motor off so this one indeed
needs to be disconnected.
Perhaps someone who has a rotax will chime in with specific details for you.
Ken
On 11/11/2014 11:23 PM, Ken Ryan wrote:
> Sheesh. Let me try again: The Rotax (major, major manufacturer of
> aircraft engines) wiring diagram seems to indicate that the
> "integrated generator" (which has an external regulator-rectifier)
> must be disconnected from the battery to avoid discharging the battery
> when it is not turning. On the other hand, the external "alternator"
> (which has a built in regulator) is wired directly to the battery,
> indicating that it does NOT need to be disconnected to avoid running
> down the battery. Is this consistent with you knowledgeable folks'
> understanding of these sorts of generators and alternators?
>
> On Tue, Nov 11, 2014 at 5:41 PM, Robert L. Nuckolls, III
> <nuckolls.bob@aeroelectric.com <mailto:nuckolls.bob@aeroelectric.com>>
> wrote:
>
> <nuckolls.bob@aeroelectric.com <mailto:nuckolls.bob@aeroelectric.com>>
>
> At 09:52 2014-11-11, you wrote:
>
> The Rotax 914 wiring diagram shows an integrated generator
> with external regulator-rectifier and an external alternator
> with built in regulator. It looks like the integrated
> generator is disconnected from the battery (by relay) when the
> master is off but the external alternator remains connected.
> The text indicates the integrated generator will run the
> battery down if not disconnected, but does not say that for
> the external alternator. Does this make sense?
>
>
> It makes sense to Rotax . . . but Rotax doesn't
> build or fly airplanes. This is a case similar
> the one where Garmin recommended an electrical sytem
> architecture in the back of one of their EFIS
> installation manuals. Never a good idea.
>
> How do YOU want your airplane to work? Check out
> Z-13/8, Z-12, and Z-14 in the 'Connection along
> with their companion narratives in Chapter 17
> and YOU decide what makes sense for you.
>
>
> Bob . . .
>
> ===================================
> br> fts!)
> r> > /www.aeroelectric.com" target="_blank">www.aeroelectric.com
> w.buildersbooks.com" target="_blank">www.buildersbooks.com
> p.com" target="_blank">www.homebuilthelp.com
> e.com" target="_blank">www.mypilotstore.com
> " target="_blank">www.mrrace.com
> target="_blank">http://www.matronics.com/contribution
> -Matt Dralle, List Admin.
> ===================================
> -
> Electric-List"
> target="_blank">http://www.matronics.com/Navigator?AeroElectric-List
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Subject: | Re: alternator / generator |
On page 110 of the Rotax 914 installation manual (July 1 2008) http://www.flyrotax.com/portaldata/5/dokus/d04273.pdf
The wiring diagram has a master battery contactor that disconnects the battery
from the aircraft electrical system including both alternators.
The rectifier/regulator that controls the integrated dynamo has a terminal "C"
that senses system voltage and enables the rectifier/regulator. It could run
down the battery over a period of time.
The external alternator has a terminal "IG" that powers the field. It would
also run down the battery if left on.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=433504#433504
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Subject: | Re: alternator / generator |
There is a Rotax list here on the Matronics server that has some very
knowledgeable people on it. There might be a thread in the archives. If
not, it's likely someone will have an answer to your question.
Raymond Julian
Kettle River, MN
The things we admire in men, kindness and generosity, openness, honesty,
understanding and feeling are the concomitants of failure in our system.
And those traits we detest, sharpness, greed, acquisitiveness, meanness,
egotism and self-interest are the traits of success. And while men
admire the quality of the first they love the produce of the second.
-John Steinbeck, novelist, Nobel laureate (1902-1968)
On 11/11/2014 10:23 PM, Ken Ryan wrote:
> Sheesh. Let me try again: The Rotax (major, major manufacturer of
> aircraft engines) wiring diagram seems to indicate that the "integrated
> generator" (which has an external regulator-rectifier) must be
> disconnected from the battery to avoid discharging the battery when it
> is not turning. On the other hand, the external "alternator" (which has
> a built in regulator) is wired directly to the battery, indicating that
> it does NOT need to be disconnected to avoid running down the battery.
> Is this consistent with you knowledgeable folks' understanding of these
> sorts of generators and alternators?
>
> On Tue, Nov 11, 2014 at 5:41 PM, Robert L. Nuckolls, III
> <nuckolls.bob@aeroelectric.com <mailto:nuckolls.bob@aeroelectric.com>>
> wrote:
>
> <nuckolls.bob@aeroelectric.com <mailto:nuckolls.bob@aeroelectric.com>__>
>
> At 09:52 2014-11-11, you wrote:
>
> The Rotax 914 wiring diagram shows an integrated generator with
> external regulator-rectifier and an external alternator with
> built in regulator. It looks like the integrated generator is
> disconnected from the battery (by relay) when the master is off
> but the external alternator remains connected. The text
> indicates the integrated generator will run the battery down if
> not disconnected, but does not say that for the external
> alternator. Does this make sense?
>
>
> It makes sense to Rotax . . . but Rotax doesn't
> build or fly airplanes. This is a case similar
> the one where Garmin recommended an electrical sytem
> architecture in the back of one of their EFIS
> installation manuals. Never a good idea.
>
> How do YOU want your airplane to work? Check out
> Z-13/8, Z-12, and Z-14 in the 'Connection along
> with their companion narratives in Chapter 17
> and YOU decide what makes sense for you.
>
>
> Bob . . .
>
> ====__==============================__=
> br> fts!)
> r> > /www.aeroelectric.com" target="_blank">www.aeroelectric.com
> w.buildersbooks.com" target="_blank">www.buildersbooks.com
> p.com" target="_blank">www.homebuilthelp.com
> e.com" target="_blank">www.mypilotstore.com
> " target="_blank">www.mrrace.com
> target="_blank">http://www.matronics.com/__contribution
> -Matt Dralle, List Admin.
> ====__==============================__=
> -
> Electric-List"
> target="_blank">http://www.matronics.com/__Navigator?AeroElectric-List
> ====__==============================__=
> FORUMS -
> _blank">http://forums.matronics.com
> ====__==============================__=
>
>
> *
>
>
> *
>
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Subject: | Re: alternator / generator |
Thanks Joe and Ken. Joe's answer I believe answers my question. I was
thinking that circuit was just for the warning lamp. Didn't know it was the
IG wire that would run down the battery.
That brings me to another question: What do those warning lamps typically
indicate? A negative current? There's one for each of the two charging
devices. Also, I have heard that these lamps must be incandescent (not
LED). Unfortunately I cannot not find a answers to even these basic
questions in the Rotax reference materials.
On Wed, Nov 12, 2014 at 5:06 AM, user9253 <fransew@gmail.com> wrote:
>
> On page 110 of the Rotax 914 installation manual (July 1 2008)
> http://www.flyrotax.com/portaldata/5/dokus/d04273.pdf
> The wiring diagram has a master battery contactor that disconnects the
> battery from the aircraft electrical system including both alternators.
> The rectifier/regulator that controls the integrated dynamo has a
> terminal "C" that senses system voltage and enables the
> rectifier/regulator. It could run down the battery over a period of time.
> The external alternator has a terminal "IG" that powers the field. It
> would also run down the battery if left on.
> Joe
>
> --------
> Joe Gores
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=433504#433504
>
>
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Subject: | Re: RS422 - RS232 |
Arrrgh!
Grand Rapids charged me $200 for an RS-422 to RS-232 adapter. [Embarassed]
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=433509#433509
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Subject: | Re: alternator / generator |
Thanks Raymond. I will attempt to check the Rotax list. I like your
Steinbeck quote. It seems familiar. Is it from Cannery Row, when talking
about the Model T?
On Wed, Nov 12, 2014 at 6:02 AM, rayj <raymondj@frontiernet.net> wrote:
>
> There is a Rotax list here on the Matronics server that has some very
> knowledgeable people on it. There might be a thread in the archives. If
> not, it's likely someone will have an answer to your question.
>
> Raymond Julian
> Kettle River, MN
>
> The things we admire in men, kindness and generosity, openness, honesty,
> understanding and feeling are the concomitants of failure in our system.
> And those traits we detest, sharpness, greed, acquisitiveness, meanness,
> egotism and self-interest are the traits of success. And while men admire
> the quality of the first they love the produce of the second. -John
> Steinbeck, novelist, Nobel laureate (1902-1968)
>
> On 11/11/2014 10:23 PM, Ken Ryan wrote:
>
>> Sheesh. Let me try again: The Rotax (major, major manufacturer of
>> aircraft engines) wiring diagram seems to indicate that the "integrated
>> generator" (which has an external regulator-rectifier) must be
>> disconnected from the battery to avoid discharging the battery when it
>> is not turning. On the other hand, the external "alternator" (which has
>> a built in regulator) is wired directly to the battery, indicating that
>> it does NOT need to be disconnected to avoid running down the battery.
>> Is this consistent with you knowledgeable folks' understanding of these
>> sorts of generators and alternators?
>>
>> On Tue, Nov 11, 2014 at 5:41 PM, Robert L. Nuckolls, III
>> <nuckolls.bob@aeroelectric.com <mailto:nuckolls.bob@aeroelectric.com>>
>> wrote:
>>
>> <nuckolls.bob@aeroelectric.com <mailto:nuckolls.bob@aeroelectric.com
>> >__>
>>
>> At 09:52 2014-11-11, you wrote:
>>
>> The Rotax 914 wiring diagram shows an integrated generator with
>> external regulator-rectifier and an external alternator with
>> built in regulator. It looks like the integrated generator is
>> disconnected from the battery (by relay) when the master is off
>> but the external alternator remains connected. The text
>> indicates the integrated generator will run the battery down if
>> not disconnected, but does not say that for the external
>> alternator. Does this make sense?
>>
>>
>> It makes sense to Rotax . . . but Rotax doesn't
>> build or fly airplanes. This is a case similar
>> the one where Garmin recommended an electrical sytem
>> architecture in the back of one of their EFIS
>> installation manuals. Never a good idea.
>>
>> How do YOU want your airplane to work? Check out
>> Z-13/8, Z-12, and Z-14 in the 'Connection along
>> with their companion narratives in Chapter 17
>> and YOU decide what makes sense for you.
>>
>>
>>
>>
>> Bob . . .
>>
>> ====__==============================__=
>> br> fts!)
>> r> > /www.aeroelectric.com" target="_blank">www.aeroelectric.com
>> w.buildersbooks.com" target="_blank">www.buildersbooks.com
>> p.com" target="_blank">www.homebuilthelp.com
>> e.com" target="_blank">www.mypilotstore.com
>> " target="_blank">www.mrrace.com
>> target="_blank">http://www.matronics.com/__contribution
>> -Matt Dralle, List Admin.
>> ====__==============================__=
>> -
>> Electric-List"
>> target="_blank">http://www.matronics.com/__Navigator?
>> AeroElectric-List
>> ====__==============================__=
>> FORUMS -
>> _blank">http://forums.matronics.com
>> ====__==============================__=
>>
>>
>>
>>
>> *
>>
>>
>> *
>>
>>
>
>
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Subject: | Re: alternator / generator |
The one guy I'm thinking of on the Rotax list has the signature:
Roger Lee
Tucson, Az.
Light Sport Repairman - Maintenance Rated
Rotax Repair Center - Heavy Maint. Rated
Home 520-574-1080 TRY HOME FIRST
Cell 520-349-7056
The list has been pretty dead lately but I bet if you post, he'll answer.
I didn't end up getting a Rotax, but he was helpful to me when I was
trying to make up my mind. I have also watched him help many others on
the list.
As far as the quote, I don't know what it's from. I found it on a
word-a-day email list I'm on and thought it deserved wider circulation.
Raymond Julian
Kettle River, MN
The things we admire in men, kindness and generosity, openness, honesty,
understanding and feeling are the concomitants of failure in our system.
And those traits we detest, sharpness, greed, acquisitiveness, meanness,
egotism and self-interest are the traits of success. And while men
admire the quality of the first they love the produce of the second.
-John Steinbeck, novelist, Nobel laureate (1902-1968)
On 11/12/2014 09:39 AM, Ken Ryan wrote:
> Thanks Raymond. I will attempt to check the Rotax list. I like your
> Steinbeck quote. It seems familiar. Is it from Cannery Row, when talking
> about the Model T?
>
> On Wed, Nov 12, 2014 at 6:02 AM, rayj <raymondj@frontiernet.net
> <mailto:raymondj@frontiernet.net>> wrote:
>
> <raymondj@frontiernet.net <mailto:raymondj@frontiernet.net>>
>
> There is a Rotax list here on the Matronics server that has some
> very knowledgeable people on it. There might be a thread in the
> archives. If not, it's likely someone will have an answer to your
> question.
>
> Raymond Julian
> Kettle River, MN
>
> The things we admire in men, kindness and generosity, openness,
> honesty, understanding and feeling are the concomitants of failure
> in our system. And those traits we detest, sharpness, greed,
> acquisitiveness, meanness, egotism and self-interest are the traits
> of success. And while men admire the quality of the first they love
> the produce of the second. -John Steinbeck, novelist, Nobel laureate
> (1902-1968)
>
> On 11/11/2014 10:23 PM, Ken Ryan wrote:
>
> Sheesh. Let me try again: The Rotax (major, major manufacturer of
> aircraft engines) wiring diagram seems to indicate that the
> "integrated
> generator" (which has an external regulator-rectifier) must be
> disconnected from the battery to avoid discharging the battery
> when it
> is not turning. On the other hand, the external "alternator"
> (which has
> a built in regulator) is wired directly to the battery,
> indicating that
> it does NOT need to be disconnected to avoid running down the
> battery.
> Is this consistent with you knowledgeable folks' understanding
> of these
> sorts of generators and alternators?
>
> On Tue, Nov 11, 2014 at 5:41 PM, Robert L. Nuckolls, III
> <nuckolls.bob@aeroelectric.com
> <mailto:nuckolls.bob@aeroelectric.com>
> <mailto:nuckolls.bob@__aeroelectric.com
> <mailto:nuckolls.bob@aeroelectric.com>>>
> wrote:
>
> Nuckolls, III"
> <nuckolls.bob@aeroelectric.com
> <mailto:nuckolls.bob@aeroelectric.com>
> <mailto:nuckolls.bob@__aeroelectric.com
> <mailto:nuckolls.bob@aeroelectric.com>>__>
>
> At 09:52 2014-11-11, you wrote:
>
> The Rotax 914 wiring diagram shows an integrated
> generator with
> external regulator-rectifier and an external alternator
> with
> built in regulator. It looks like the integrated
> generator is
> disconnected from the battery (by relay) when the
> master is off
> but the external alternator remains connected. The text
> indicates the integrated generator will run the battery
> down if
> not disconnected, but does not say that for the external
> alternator. Does this make sense?
>
>
> It makes sense to Rotax . . . but Rotax doesn't
> build or fly airplanes. This is a case similar
> the one where Garmin recommended an electrical sytem
> architecture in the back of one of their EFIS
> installation manuals. Never a good idea.
>
> How do YOU want your airplane to work? Check out
> Z-13/8, Z-12, and Z-14 in the 'Connection along
> with their companion narratives in Chapter 17
> and YOU decide what makes sense for you.
>
>
> Bob . . .
>
> ====__========================__======__=
> br> fts!)
> r> > /www.aeroelectric.com <http://www.aeroelectric.com>"
> target="_blank">www.__aeroelectric.com <http://www.aeroelectric.com>
> w.buildersbooks.com <http://w.buildersbooks.com>"
> target="_blank">www.__buildersbooks.com
> <http://www.buildersbooks.com>
> p.com <http://p.com>" target="_blank">www.__homebuilthelp.com
> <http://www.homebuilthelp.com>
> e.com <http://e.com>" target="_blank">www.__mypilotstore.com
> <http://www.mypilotstore.com>
> " target="_blank">www.mrrace.com <http://www.mrrace.com>
> target="_blank">http://www.__matronics.com/__contribution
> <http://www.matronics.com/__contribution>
> -Matt Dralle, List Admin.
> ====__========================__======__=
> -
> Electric-List"
>
> target="_blank">http://www.__matronics.com/__Navigator?__AeroElectric-List
> <http://www.matronics.com/__Navigator?AeroElectric-List>
> ====__========================__======__=
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> <http://forums.matronics.com>
> ====__========================__======__=
>
>
> *
>
>
> *
>
>
> ====__==============================__=
> br> fts!)
> r> > /www.aeroelectric.com" target="_blank">www.aeroelectric.com
> w.buildersbooks.com" target="_blank">www.buildersbooks.com
> p.com" target="_blank">www.homebuilthelp.com
> e.com" target="_blank">www.mypilotstore.com
> " target="_blank">www.mrrace.com
> target="_blank">http://www.matronics.com/__contribution
> -Matt Dralle, List Admin.
> ====__==============================__=
> -
> Electric-List"
> target="_blank">http://www.matronics.com/__Navigator?AeroElectric-List
> ====__==============================__=
> FORUMS -
> _blank">http://forums.matronics.com
> ====__==============================__=
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>
>
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>
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Subject: | Re: alternator / generator |
At 22:23 2014-11-11, you wrote:
>Sheesh. Let me try again: The Rotax (major, major manufacturer of
>aircraft engines) wiring diagram seems to indicate that the
>"integrated generator" (which has an external regulator-rectifier)
>must be disconnected from the battery to avoid discharging the
>battery when it is not turning. On the other hand, the external
>"alternator" (which has a built in regulator) is wired directly to
>the battery, indicating that it does NOT need to be disconnected to
>avoid running down the battery. Is this consistent with you
>knowledgeable folks' understanding of these sorts of generators and
>alternators?
Short answer: Yes, this is consistent with the
way these two critters work.
BOTH devices are alternators. The word "dynamo"
has been often used to describe the built-in, permanent
magnet devices common to all Rotax engines, Jabiru,
et als. The one built into the 912 engine is a single-
phase device that requires a special rectifier/regulator
to convert the wild-frequency, wild-voltage output
from the alternator into stable DC.
Here's one of several conversations that have transpired
here on the list about PM alternators and their rectifier/
regulators . . .
http://tinyurl.com/mpxxech
If ROTAX is still using the Ducati rectifier/regulator
I'm familiar with, this device DOES draw milliamps
of current back-fed into the output wires when
then engine is stopped. But if you configure your
P/M alternator to drive the electrical system
DOWNSTREAM of the battery master relay, then the
alternator is powered down when the master switch
is opened and the powered-down draw is eliminated.
The other device is legacy wound-field technology
wherein the regulator is small enough to be included
inside the alternator . . . as on most cars.
The b-lead terminal of the wound-field alternator
is the (+) output terminal from an array of diodes
that prevent any back-flow during power down. Hence
the b-lead CAN be left connected to the battery
at all times . . . cars do it. But it's not been
done in T/C aircraft that I know of.
Suggest you consider a Z-13/8 architecture . . .
http://tinyurl.com/kgg8nva
. . . . which describes a recommended architecture
for your pair of alternators (the wound-field alternator
shows an external regulator . . . your internally
regulated alternator works there too).
The two alternators and their regulators are described
in the AeroElectric Connection which is available
for about $20 from a variety of sources . . . or
you can download here
http://tinyurl.com/pt97pha
What airplane are you building?
Bob . . .
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Subject: | Re: lithium facts |
I'm responding to a couple different bits of this thread here.
On 11/08/2014 05:14 PM, Robert L. Nuckolls, III wrote:
>> <jan_de_jong@casema.nl>
>>
>> Tesla does not use LiFePO4, but something more energetic, I believe:
>> http://batteryuniversity.com/learn/article/safety_of_lithium_ion_batteries
>>
>
> here is one of several articles I see that prompted my
> assertion . . .
>
> http://tinyurl.com/pqo59cr
Tesla uses Panasonic NCR18650A 3100mAh cells which are Lithium Nickel
Cobalt Aluminum Oxide (NCA). The Tesla Roadster used Lithium Cobalt Oxide.
> I've been working on a series of articles for Kitplanes
> on the use of lithium batteries in airplanes. Energetic
> concerns for making the switch are centered on the extra-
> ordinary ability of lithium batteries to catch fire . . .
> and set other things on fire too.
My guess is that most of the RC and laptops that have melted down had
Lithium Cobalt Oxide batteries. They have a thermal run-away temperature
of only 150C. They also tend to get hot in use which exacerbates the
problem. LiFePo4 can go to 270C before they meltdown and they don't
generate anywhere near as much heat in operation. But they have less
energy density which isn't really that much of an issue in the case of
an aircraft or automobile 12v battery. The Boeing 787 batteries that
burned up were Lithium Cobalt Oxide. They should have taken the small
weight penalty and used LiFePo4, IMO.
> A 3-cell lithium battery gets fully stuffed at 12.6 volts,
> a 4-cell array would like to see 16.8 volts. Hmmmm . . .
> what's the elegant design goal? We've read in the journals
> that the hybrid car guys design their charge-discharge
> profiles to operate state-of-charge over a range of 20-80%
> to maximize the battery's service life. What happens if
> we charge a 4-cell array at 14.4/4 or only 3.6 volts per
> cell?
While most of the lithium chemistries are nominally 3.6-3.7 volts,
LiFoPo4 is only 3.2 volts. Most of my dealings with these cells are in
electric cars. Motive is a different use than a starting battery but
we've still learned a lot. 8 years ago the LiFoPo4 manufacturers were
saying to charge their cells to 4.2 volts and people were having a lot
of failures. They've since modified that to an upper limit of around 3.6
volts which works well when using 4 cells to build a starting battery.
Unlike your testing, in my testing of the larger format cells from CALB
I found little energy could be pushed into the cells above 3.6 volts.
The charge curve is very flat but when it hits 3.6 the voltage rises to
4 very quickly. And when I discharge the cells from 3.6 down to where
the voltage starts to fall dramatically (under 3 volts) I get pretty
much the full rated amp-hours out of them.
Specs and factory graphs of the cells I've tested are here:
http://evwest.com/support/CALB-CA100Ah.pdf
You said you were testing LiFePo4 cells and that 3.6 volts was only half
their capacity. It makes me wonder what the recipe of those cells is
because that behavior fits more with other lithium chemistries, but not
with LiFePo4. It is hard to get consistent data on lithium cells because
the manufacturers are always experimenting with the makeup of the cells
and it can sometimes have dramatic performance differences.
Other considerations for people thinking of making the switch to lithium
is that LiFePo4 doesn't like to be charged below freezing. I don't
particularly like to fly below freezing either, but I have done it. You
can discharge the cells down to -20C so starting the plane might not be
an issue but it would suck to get to your destination and discover that
the battery got fried being charged back up in the air. I have not
tested this--I put heated battery boxes in my electric vehicle.
The good thing--in addition to less weight--is almost no self-discharge.
I had 38 cells sitting in my basement for 6 months and the voltage was
the same within 2 hundredths of a volt on every cell but one. And I got
that one replaced because self-discharge is a good indicator of an
internal soft short (a piece of metal dust or other contaminate that's
conducting power between anode and cathode).
I have 2 electric vehicles and in one of them I had replaced a full-size
lead-acid battery with a garden tractor battery because I didn't need
the starting amps and wanted to save some weight. I just replaced that
one with a tiny little lithium battery from Deltran (aka Battery
Tender). It pretty much just needs to keep the radio channels set, some
instrumentation alive and provide enough urge to close the contactors
when I turn the key. It's been in two days and I'm definitely curious to
see how it stands this winter. They sell them for "motorsport" uses like
motorcycles and ATVs. Most people put their bikes away in the winter
here in New England but people do use ATVs year-round. I don't know how
those people would like these batteries but for $70 I was willing to
experiment.
--Rick
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Subject: | Re: alternator / generator |
At 09:27 2014-11-12, you wrote:
>Thanks Joe and Ken. Joe's answer I believe
>answers my question. I was thinking that circuit
>was just for the warning lamp. Didn't know it
>was the IG wire that would run down the battery.=C2
>
>That brings me to another question: What do
>those warning lamps typically indicate? A
>negative current? There's one for each of the
>two charging devices. Also, I have heard that
>these lamps must be incandescent (not LED).
>Unfortunately I cannot not find a answers to
>even these basic questions in the Rotax reference materials.
The warning output from these simple regulators is
generally limited to showing that the alternator is
not turning (broken belt) or output failed (broken
wire).
Emacs!
The exemplar schematic for the PM alternator warning light (2)
shows that the light is dark any time the alternator is
rotating and delivering some voltage . . . even when that
voltage is too low to charge a battery or run your accessories.
The preferred methodology for detecting alternator
insufficiency is LOW VOLTAGE WARN set to light a lamp
any time the bus is less than about 13.0 volts. A
lead-acid battery system cannot rise above 13.0 unless
the alternator pushes it up there. So voltage monitoring
is the one-light-tells-all-tales approach to annunciating
system health.
This is why none of the Z-figures utilize the lamp output
lead on any of the PM rectifier/regulators depicted.
Bob . . .
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Subject: | Re: alternator / generator |
Thanks Bob. I do have the book. I am building a Just Aircraft SuperSTOL. A
previous lister said that the IG wire from the external alternator needs to
be disconnected to avoid drawing down the battery, which it is on the Rotax
diagram (via the master switch). Are you saying that you disagree with this
and that the IG wired does not need to be disconnected to avoid drawing
down the battery?
On Wed, Nov 12, 2014 at 7:44 AM, Robert L. Nuckolls, III <
nuckolls.bob@aeroelectric.com> wrote:
> nuckolls.bob@aeroelectric.com>
>
> At 22:23 2014-11-11, you wrote:
>
>> Sheesh. Let me try again: The Rotax (major, major manufacturer of
>> aircraft engines) wiring diagram seems to indicate that the "integrated
>> generator" (which has an external regulator-rectifier) must be disconnected
>> from the battery to avoid discharging the battery when it is not turning.
>> On the other hand, the external "alternator" (which has a built in
>> regulator) is wired directly to the battery, indicating that it does NOT
>> need to be disconnected to avoid running down the battery. Is this
>> consistent with you knowledgeable folks' understanding of these sorts of
>> generators and alternators?
>>
>
>
> Short answer: Yes, this is consistent with the
> way these two critters work.
>
>
> BOTH devices are alternators. The word "dynamo"
> has been often used to describe the built-in, permanent
> magnet devices common to all Rotax engines, Jabiru,
> et als. The one built into the 912 engine is a single-
> phase device that requires a special rectifier/regulator
> to convert the wild-frequency, wild-voltage output
> from the alternator into stable DC.
>
> Here's one of several conversations that have transpired
> here on the list about PM alternators and their rectifier/
> regulators . . .
>
> http://tinyurl.com/mpxxech
>
>
> If ROTAX is still using the Ducati rectifier/regulator
> I'm familiar with, this device DOES draw milliamps
> of current back-fed into the output wires when
> then engine is stopped. But if you configure your
> P/M alternator to drive the electrical system
> DOWNSTREAM of the battery master relay, then the
> alternator is powered down when the master switch
> is opened and the powered-down draw is eliminated.
>
> The other device is legacy wound-field technology
> wherein the regulator is small enough to be included
> inside the alternator . . . as on most cars.
>
> The b-lead terminal of the wound-field alternator
> is the (+) output terminal from an array of diodes
> that prevent any back-flow during power down. Hence
> the b-lead CAN be left connected to the battery
> at all times . . . cars do it. But it's not been
> done in T/C aircraft that I know of.
>
> Suggest you consider a Z-13/8 architecture . . .
>
> http://tinyurl.com/kgg8nva
>
>
> . . . . which describes a recommended architecture
> for your pair of alternators (the wound-field alternator
> shows an external regulator . . . your internally
> regulated alternator works there too).
>
> The two alternators and their regulators are described
> in the AeroElectric Connection which is available
> for about $20 from a variety of sources . . . or
> you can download here
>
> http://tinyurl.com/pt97pha
>
> What airplane are you building?
>
>
> Bob . . .
>
>
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Subject: | Re: alternator / generator |
At 07:23 2014-11-12, you wrote:
>
>Yes (probably)
>If you have the external alternator connect it to a battery and
>measure the standby current for a definitive answer.
>Most vehicles leave the alternator connected 24/7 and they usually
>draw an acceptable couple of mA drain. Sounds like that is the case
>for your unit although I also have been appalled by the
>documentation accompanying equipment from "major manufacturers" so I
>would not put a lot of money on it.
>For example the 40A IR Nippondenso that I use was only installed on
>non road equipment and it draws 2 Amps with the motor off so this
>one indeed needs to be disconnected.
Your observation illustrates the fact that not all
alternators are the same. Back in the day, externally
regulated alternators got their field current from
the switched bus in an automobile. One-wire alternators
will get their power from the b-terminal which means
that full field current will be drawn into the b-terminal
when the alternator is not running . . . but still
connected to the battery.
The condition becomes moot when you adopt the legacy
philosophy for minimizing hot-wires when the master
switch is off. This philosophy bypasses all the
risks for powered-down, parasitic currents that might
deplete the battery in a parked airplane . . . it also
goes toward achieving 'max-cold' wiring for reducing
risks of after crash fire.
Bob . . .
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Subject: | Re: alternator / generator |
At 07:23 2014-11-12, you wrote:
>
>Yes (probably)
>If you have the external alternator connect it to a battery and
>measure the standby current for a definitive answer.
>Most vehicles leave the alternator connected 24/7 and they usually
>draw an acceptable couple of mA drain. Sounds like that is the case
>for your unit although I also have been appalled by the
>documentation accompanying equipment from "major manufacturers" so I
>would not put a lot of money on it.
>For example the 40A IR Nippondenso that I use was only installed on
>non road equipment and it draws 2 Amps with the motor off so this
>one indeed needs to be disconnected.
Your observation illustrates the fact that not all
alternators are the same. Back in the day, externally
regulated alternators got their field current from
the switched bus in an automobile. One-wire alternators
will get their power from the b-terminal which means
that full field current will be drawn into the b-terminal
when the alternator is not running . . . but still
connected to the battery.
The condition becomes moot when you adopt the legacy
philosophy for minimizing hot-wires when the master
switch is off. This philosophy bypasses all the
risks for powered-down, parasitic currents that might
deplete the battery in a parked airplane . . . it also
goes toward achieving 'max-cold' wiring for reducing
risks of after crash fire.
Bob . . .
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Subject: | Re: alternator / generator |
Yes, Roger Lee is the Rotax expert and likes to answer Rotax questions. I have
no experience with the Rotax external alternator. I posted above that leaving
the IG terminal connected to the battery would drain it. That is because that
terminal is described as "Field Circuit" on page 123 of the Rotax installation
manual. Sometimes the actual meaning gets lost in translation from German.
Even if the field is not actually powered by the IG terminal, (but by the B
lead) I would not leave it connected to the battery with the engine off.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=433530#433530
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Subject: | Re: alternator / generator |
At 11:01 2014-11-12, you wrote:
>Thanks Bob. I do have the book. I am building a Just Aircraft
>SuperSTOL. A previous lister said that the IG wire from the external
>alternator needs to be disconnected to avoid drawing down the
>battery, which it is on the Rotax diagram (via the master switch).
>Are you saying that you disagree with this and that the IG wired
>does not need to be disconnected to avoid drawing down the battery?
Ooops . . . sorry 'bout that. We're talking about the wound-field
alternator . . . not the PM machine. That light doesn't work with much more
intelligence than that annunciator on the PM rectifier/regulator.
It's definitely dark when the alternator is working but may
not light when the alternator is inadequate to system
needs. I don't use those outputs either.
If you're planning on ACTIVE NOTIFICATION OF LOW VOLTS then
you can simply leave the light off the panel and leave the
terminal disconnected.
But you're correct, when wired per the Rotax drawing, IG gets
disconnected when the big-alternator switch is OFF . . . so if
you plan to use the light, wired as shown eliminates the
concern.
An interesting feature of their wiring gives you no control
over the little alternator . . . it is automatically switched
ON via relay (58) with an unnecessary, 1A fuse in the coil
lead. This relay closes as soon as you turn on the master
switch and will stay closed as long as the engine is running
even if battery relay (38) is opened. Bringing engine
rpm down will slowly drop voltage on the bus . . . and
might cause the little-alternator relay to drop but
this raises all kinds of questions about the behaviors
of the ship's accessories.
The relay will certainly drop after the engine is shut
down.
Another interesting feature uses the little-alternator
output to power up one of two fuel pumps whether or not
the master switch is ON.
The 80A breaker is, in US TC aircraft philosophy, not
necessary or useful.
Emacs!
Bob . . .
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Subject: | Re: alternator / generator |
Thanks Joe. Although I have been studying the diagram for a long time, to
me it is like trying to read a foreign language. I now realize that the IG
is indeed disconnected from the battery when the master is off, because
when the master is off the battery relay is open, and that disconnects
everything except the starter. Your point about the German translation is
well taken. It amazes me that a company that makes as many engines as Rotax
(according to December 2014 Kitplanes it's 215,000 per year) doesn't think
it's important to hire a competent German-English translator.
On Wed, Nov 12, 2014 at 9:15 AM, user9253 <fransew@gmail.com> wrote:
>
> Yes, Roger Lee is the Rotax expert and likes to answer Rotax questions. I
> have no experience with the Rotax external alternator. I posted above that
> leaving the IG terminal connected to the battery would drain it. That is
> because that terminal is described as "Field Circuit" on page 123 of the
> Rotax installation manual. Sometimes the actual meaning gets lost in
> translation from German. Even if the field is not actually powered by the
> IG terminal, (but by the B lead) I would not leave it connected to the
> battery with the engine off.
> Joe
>
> --------
> Joe Gores
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=433530#433530
>
>
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Subject: | Re: alternator / generator |
Thanks Bob,
I was wondering about that 80 amp fuse. It seems better to connect the bus
directly to the battery. With regards to the 1 amp fuse that you say is
unnecessary, why do you say that? Isn't it there to protect the wire that
runs from the battery to relay 58? I think the reasoning behind wiring one
fuel pump to the generator, is because the 914 relies on an electric fuel
pump, and they are trying to provide two independent power sources for each
pump.
On Wed, Nov 12, 2014 at 9:18 AM, Robert L. Nuckolls, III <
nuckolls.bob@aeroelectric.com> wrote:
> At 11:01 2014-11-12, you wrote:
>
> Thanks Bob. I do have the book. I am building a Just Aircraft SuperSTOL. A
> previous lister said that the IG wire from the external alternator needs to
> be disconnected to avoid drawing down the battery, which it is on the Rotax
> diagram (via the master switch). Are you saying that you disagree with this
> and that the IG wired does not need to be disconnected to avoid drawing
> down the battery?
>
>
> Ooops . . . sorry 'bout that. We're talking about the wound-field
> alternator . . . not the PM machine. That light doesn't work with much
> more
> intelligence than that annunciator on the PM rectifier/regulator.
> It's definitely dark when the alternator is working but may
> not light when the alternator is inadequate to system
> needs. I don't use those outputs either.
>
> If you're planning on ACTIVE NOTIFICATION OF LOW VOLTS then
> you can simply leave the light off the panel and leave the
> terminal disconnected.
>
> But you're correct, when wired per the Rotax drawing, IG gets
> disconnected when the big-alternator switch is OFF . . . so if
> you plan to use the light, wired as shown eliminates the
> concern.
>
> An interesting feature of their wiring gives you no control
> over the little alternator . . . it is automatically switched
> ON via relay (58) with an unnecessary, 1A fuse in the coil
> lead. This relay closes as soon as you turn on the master
> switch and will stay closed as long as the engine is running
> even if battery relay (38) is opened. Bringing engine
> rpm down will slowly drop voltage on the bus . . . and
> might cause the little-alternator relay to drop but
> this raises all kinds of questions about the behaviors
> of the ship's accessories.
>
> The relay will certainly drop after the engine is shut
> down.
>
> Another interesting feature uses the little-alternator
> output to power up one of two fuel pumps whether or not
> the master switch is ON.
>
> The 80A breaker is, in US TC aircraft philosophy, not
> necessary or useful.
>
>
> [image: Emacs!]
>
>
> Bob . . .
>
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Subject: | Excellent value in test equipment . . . |
For fellow electron herders on the List:
Just received this item ordered for a client.
http://tinyurl.com/qd2thap
It's capabilities stack up favorably with
readings taken with my Tektronix/Fluke stuff.
Bob . . .
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Subject: | Re: lithium facts |
My head is buzzing from all the lithium that we are talking about, although
I am now less bipolar.
Lessee---- If I am an aircraft with standard 12(14)V electrical system and
standard charging system, what will I see and what difference will I see if
I have a starved electrolyte battery vs a liFEPO4 battery. As an aircraft,
I, as a dumb airplane, cannot really, nor do I want to, understand, the
cell structure, charging techniques, ideal voltage etc. All I really want to
know is will it start my engine and if my charging system goes TU how much
time will I have available to energize my electrical system (radios, EFI,
electronic ignition system, ie. just those elements on my essential buss.
I am aware, even with my airplane brain, I think that it is located
somewhere in my elevator, that either battery chemistry can start my propeller
propellering. and if that were the only thing I needed, I would certainly
opt for the lightest battery possible. My concern is that in the case of loss
of the alternator (generator if so equipped), how long will my vitals stay
vital. Other than that, I really don't give a rat's tail-cone.
So lets take a non-starting, constant load of say--15A and compare a lead
acid battery of a given size and a LIFEPo4 battery (Or batteries) of EQUAL
weight.How long would I last with each before the energy (since being an
aircraft I don't know volts from amps (I just buzz around saying OOOOOOM))
is low enough to start effecting my vitals I am going to assume that the
charging method is the standard basic settings of the aircraft with the
battery(s) charged to max with that system.
An additional comparison should be made LI to LI using their cell balancers
and without. An additional test should be done with the charging system
set for the "Ideal LiFEPOs charging voltage).
Once that figure is derived, it would be a simple matter to determine what
weight (size) of the LI type would be equivalent to that of the PB variety
for my selfish needs.
This is not to say that the longevity of each type of battery with the
similar charging voltage is trivial.
Of course it is very easy to suggest the research, not being able nor
inclined to do it myself.
I think that one or two of the Major aircraft battery manufacturers are now
offering Li batteries (probably with an attached STC. My guess is that
they have already done the above recommended testing.
I'm still trying to decide what kind of chemistry I will be carrying in my
battery area but my builder won't have to make that decision for a while.
Respectfully submitted
Aerocanard 948RG
(Rich)
In a message dated 11/12/2014 10:59:53 A.M. Central Standard Time,
richard.beebe@yale.edu writes:
--> AeroElectric-List message posted by: Rick Beebe
<richard.beebe@yale.edu>
I'm responding to a couple different bits of this thread here.
On 11/08/2014 05:14 PM, Robert L. Nuckolls, III wrote:
>> <jan_de_jong@casema.nl>
>>
>> Tesla does not use LiFePO4, but something more energetic, I believe:
>>
http://batteryuniversity.com/learn/article/safety_of_lithium_ion_batteries
>>
>
> here is one of several articles I see that prompted my
> assertion . . .
>
> http://tinyurl.com/pqo59cr
Tesla uses Panasonic NCR18650A 3100mAh cells which are Lithium Nickel
Cobalt Aluminum Oxide (NCA). The Tesla Roadster used Lithium Cobalt Oxide.
> I've been working on a series of articles for Kitplanes
> on the use of lithium batteries in airplanes. Energetic
> concerns for making the switch are centered on the extra-
> ordinary ability of lithium batteries to catch fire . . .
> and set other things on fire too.
My guess is that most of the RC and laptops that have melted down had
Lithium Cobalt Oxide batteries. They have a thermal run-away temperature
of only 150C. They also tend to get hot in use which exacerbates the
problem. LiFePo4 can go to 270C before they meltdown and they don't
generate anywhere near as much heat in operation. But they have less
energy density which isn't really that much of an issue in the case of
an aircraft or automobile 12v battery. The Boeing 787 batteries that
burned up were Lithium Cobalt Oxide. They should have taken the small
weight penalty and used LiFePo4, IMO.
> A 3-cell lithium battery gets fully stuffed at 12.6 volts,
> a 4-cell array would like to see 16.8 volts. Hmmmm . . .
> what's the elegant design goal? We've read in the journals
> that the hybrid car guys design their charge-discharge
> profiles to operate state-of-charge over a range of 20-80%
> to maximize the battery's service life. What happens if
> we charge a 4-cell array at 14.4/4 or only 3.6 volts per
> cell?
While most of the lithium chemistries are nominally 3.6-3.7 volts,
LiFoPo4 is only 3.2 volts. Most of my dealings with these cells are in
electric cars. Motive is a different use than a starting battery but
we've still learned a lot. 8 years ago the LiFoPo4 manufacturers were
saying to charge their cells to 4.2 volts and people were having a lot
of failures. They've since modified that to an upper limit of around 3.6
volts which works well when using 4 cells to build a starting battery.
Unlike your testing, in my testing of the larger format cells from CALB
I found little energy could be pushed into the cells above 3.6 volts.
The charge curve is very flat but when it hits 3.6 the voltage rises to
4 very quickly. And when I discharge the cells from 3.6 down to where
the voltage starts to fall dramatically (under 3 volts) I get pretty
much the full rated amp-hours out of them.
Specs and factory graphs of the cells I've tested are here:
http://evwest.com/support/CALB-CA100Ah.pdf
You said you were testing LiFePo4 cells and that 3.6 volts was only half
their capacity. It makes me wonder what the recipe of those cells is
because that behavior fits more with other lithium chemistries, but not
with LiFePo4. It is hard to get consistent data on lithium cells because
the manufacturers are always experimenting with the makeup of the cells
and it can sometimes have dramatic performance differences.
Other considerations for people thinking of making the switch to lithium
is that LiFePo4 doesn't like to be charged below freezing. I don't
particularly like to fly below freezing either, but I have done it. You
can discharge the cells down to -20C so starting the plane might not be
an issue but it would suck to get to your destination and discover that
the battery got fried being charged back up in the air. I have not
tested this--I put heated battery boxes in my electric vehicle.
The good thing--in addition to less weight--is almost no self-discharge.
I had 38 cells sitting in my basement for 6 months and the voltage was
the same within 2 hundredths of a volt on every cell but one. And I got
that one replaced because self-discharge is a good indicator of an
internal soft short (a piece of metal dust or other contaminate that's
conducting power between anode and cathode).
I have 2 electric vehicles and in one of them I had replaced a full-size
lead-acid battery with a garden tractor battery because I didn't need
the starting amps and wanted to save some weight. I just replaced that
one with a tiny little lithium battery from Deltran (aka Battery
Tender). It pretty much just needs to keep the radio channels set, some
instrumentation alive and provide enough urge to close the contactors
when I turn the key. It's been in two days and I'm definitely curious to
see how it stands this winter. They sell them for "motorsport" uses like
motorcycles and ATVs. Most people put their bikes away in the winter
here in New England but people do use ATVs year-round. I don't know how
those people would like these batteries but for $70 I was willing to
experiment.
--Rick
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Subject: | Aerobatic wiring schematic |
Hi all=2C This is more directed at Bob but anyone else feel free to comment
. I have been in email discussion with Greg Jones at B&C about a few things
on my Pitts Special and he suggested that Bob would be best to speak with
about the Aerobatic Aircraft wiring schematic on their website=2C it was ma
de mention that Bob originally drew it up.
Drawing number 420-506
http://www.bandc.biz/pdfs/420-506_Indexed_Diagram_with_BOM.pdf
http://www.bandc.biz/pdfs/420-506_REVB.pdf
I had a couple of questions.
Looking at the mag switch portion of the diagram. Should it not be drawn th
at the impulse magneto is the OFF-START/ON?
If the OFF-START/ON switch (Right Mag) is used and the start button engaged
the starter would not power unless the Left Mag were also on.
Am I missing something here?
Might I also ask what the function of the momentary side of the mag switch
is for - (ON)-OFF-ON?
I am running an SD-8 dynamo and my intention is to have no master solenoid
(as shown in the schematic) and also not use a starter solenoid=2C I am usi
ng the Skytec NL starter and they have an option of wiring the starter usin
g the internal solenoid of the starter. Does anyone foresee any problems he
re?
My biggest concern was having the starter engage and not be able to shut it
off. I see the B&C starter has an Emergency Starter Off how does this disa
ble their system as the way I see it=2C if the solenoid contacts welded the
mselves closed=2C the starter is still feed power.
I contacted Skytec and they said=2C due to the way their starter is made th
is can't happen so a starter 'kill' isn't required. If power is removed fro
m the start solenoid the starter 'will' disengage=2C I guess the only real
danger in this situation is a stuck start switch but turning off the master
would solve that I guess if I fitted a starter warning engaged warning lig
ht. Cheers=2C Ryan
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Subject: | Re: lithium facts |
On 11/12/2014 02:28 PM, ARGOLDMAN@aol.com wrote:
> So lets take a non-starting, constant load of say--15A and compare a
> lead acid battery of a given size and a LIFEPo4 battery (Or
> batteries) of EQUAL weight.How long would I last with each before the
> energy (since being an aircraft I don't know volts from amps (I just
> buzz around saying OOOOOOM)) is low enough to start effecting my vitals
> I am going to assume that the charging method is the standard basic
> settings of the aircraft with the battery(s) charged to max with that
> system.
Equal weight? No contest although I'm too lazy to do the math right now.
Here's an anecdotal answer though. I have a Ford Ranger that was
converted to electric. 144 volts with 24 215Ah lead-acid batteries. They
weighed 1600 pounds and would drive the truck about 40 miles.
I replaced them with 38 100ah lithium cells. Still 144 volts but only
weighing 347 pounds. The truck will go about 50 miles and it does it in
a much more spritely manner.
There are some interesting considerations for your test. One is that
voltage of lead-acid batteries decreases linearly with state of charge
(SOC). From roughly 12.65 volts fully charged to 11.89 volts completely
empty. At what point in that slope, though, will your electronics start
to behave erratically? I don't know. In general, for long life, you
don't want to discharge more than 50% or down to 12.24 volts.
LiFePo4 cells have a very flat discharge curve. 4 cells tied together
will be at roughly 13.2 volts full and will drop to 12.6 before suddenly
dropping to 0 as the battery reaches empty. You'd like to avoid that
drop but as far as your plane is concerned the battery will look full
for the entire discharge time which could use up almost all the capacity
of the battery.
--Rick
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This seems to have generated some interest so I will expand.
I presently have a Becker atc4401 Mode A/C thansponder and a Garmin 430W
gps/com/nav.
Don't know where 432W came from, sorry for the confusion.
The Becker bxp6401 Mode S ia a slide in replacement with an extra
connector for the Mode S connection.
It is not in a rack so "slide in" means the same pin-outs on the main
connector.
There is also a dongle that is programmed to provide the Mode S address.
It definitely has extended squitter. It also does Mode A and C.
Accord in to Garmin the 430W will operate with any capable Mode S
transponder.
So this seems to be a viable solution, particularly if one already has
the Becker Mode A/C.
Jim Bean
On Mon, Nov 10, 2014 at 07:09 PM, James Bean wrote:
In starting to think about ADS-B one way to get out only would be a
Mode-S transponder hooked to the existing Garmin 432W. The 432 speaks
RS232 and the transponder slide in replacement speaks RS422. There are
converters available for under 20 bucks. Is it that simple?
Jim Bean
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