Today's Message Index:
----------------------
1. 06:46 AM - Re: Wires that pass near a Magnetometer (bcone1381)
2. 06:51 AM - Re: Z-13/8 review request (user9253)
3. 07:15 AM - Re: Z-13/8 review request ()
4. 11:14 AM - Re: Z-13/8 review request (Charlie England)
5. 02:11 PM - Re: ARINC Wiring Shield? (jsajpf)
6. 02:20 PM - Re: Z-13/8 review request (Charlie England)
7. 04:55 PM - Re: Z-13/8 review request (jcarne)
8. 05:07 PM - Re: Z-13/8 review request (jcarne)
9. 05:16 PM - Re: Z-13/8 review request (jcarne)
10. 05:25 PM - Re: Re: Z-13/8 review request (Kelly McMullen)
11. 05:38 PM - Re: Z-13/8 review request (jcarne)
12. 05:41 PM - Re: Z-13/8 review request (jcarne)
13. 05:57 PM - Re: Z-13/8 review request (jcarne)
14. 07:03 PM - Re: Re: Z-13/8 review request (Charlie England)
15. 07:41 PM - Re: Re: Z-13/8 review request (Charlie England)
16. 09:22 PM - Re: Z-13/8 review request (jcarne)
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| Subject: | Re: Wires that pass near a Magnetometer |
I'm very grateful and very impressed with your help on this Bob! Thanks so much.
Brooks
--------
Brooks Cone
Bearhawk Patrol Kit Build
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=491116#491116
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| Subject: | Re: Z-13/8 review request |
Two 15 amp fuses are not a mistake. Suppose that a short circuit blows the
battery fuse. Now what is going to stop high current from flowing through the
diode?
I agree with you that a shunt is not needed. An ammeter is good for
troubleshooting. But fly the plane and save troubleshooting until on the
ground. The EFIS voltmeter is all that is needed to tell if the alternator is
working or not.
I agree with Charlie that the 15 amp fuses are too small. When two fuses
are in series (main fuse and branch fuse), a hard short circuit could blow both
unless there is a very large difference in fuse sizes. Having fuses in series
is usually not a good idea.
The ANL fuse for the main power bus is an unnecessary failure point. But
since you have already installed it, insulate it well. Try to eliminate potential
sparks after a forced landing.
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=491117#491117
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| Subject: | Z-13/8 review request |
Jereme,
I'm a complete novice when it comes to the actual electronics involved,
so I'll leave it to Bob and the other experts to comment on those
aspects.
But I did notice on the e-bus diagram that your GPS is NOT wired to the
e-bus. If you're flying IFR (or at night), wouldn't the ability to
navigate be fairly critical at that point? Personally, I think I'd want
that on the e-bus, but maybe I'm nuts...
I also noticed you DO have the Garmin G5 on the e-bus. I'm sure you
know Garmin offers a backup battery, with up to 4 hours endurance. If
you include that battery in your plans, could you safely remove the G5
from the e-bus? I know it's a tiny load, but every little bit helps,
right?
Jim Parker
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| Subject: | Re: Z-13/8 review request |
On 8/28/2019 10:56 PM, Charlie England wrote:
> On 8/28/2019 10:22 PM, jcarne wrote:
>> <jeremejcarne@gmail.com>
>>
>> Hello everyone, first time poster here. I would love it if you guys
>> would review my Z-13/8. Thanks in advance!
>>
>> This diagram is Bob's Z-13/8 with VERY FEW modifications. I'll point
>> them out in the pics below.
>>
>> First here are the pics, sorry they are so big but I'm thinking this
>> is the only way you will be able to read anything.
>>
>> I am aware of how to size wires per AC 43.13. However, I went with
>> what the manufacturer recommended instead
>> (which was always bigger than AC43.13 or right on). This is why I
>> have at times two different gauges for the same circuit size.
>> Yes I know in most instances I can use 22 awg where I speced 20 awg.
>> I already have plenty of both sizes so no worry there.
>>
>> Would you all mind taking some time to look it over for any blatant
>> errors? Mega thank you for taking the time.
>>
>> First up is the top of the diagram where the backup B&C SD-8 is.
>> The changes here are the shunt and ANL positions. I have already
>> installed two ANL fuses on my firewall as I would prefer both battery
>> and alternator lines be protected. Many find it unnecessary which may
>> be the case but it's already done and installed. I have also removed
>> the
>> shunt for the backup alternator because if I am ever running on it I
>> will
>> know my e-bus is sized right for the current and I can simply monitor
>> bus
>> voltage. If you REALLY think I need a shunt give me a good reason and I
>> may install one but at this time I don't see the point.
>>
>> (https://flic.kr/p/2h6xoGh)1 (https://flic.kr/p/2h6xoGh) by Jereme
>> Carne (https://www.flickr.com/photos/151084592@N02/), on Flickr
>>
>> Next up is the lower meatier part of the diagram. I eliminated the
>> electronic
>> ignition and put in for mags instead. I know many like having a
>> dedicated
>> start button but I really like the left mag also being your start
>> switch. This method
>> is also wired such that the right mag must be off to send power to
>> the starter. As far as
>> mag switches and the batt/alt switch they are locking toggles. The
>> mags lock in off and
>> on with momentary up. The batt/alt switch locks in all three
>> positions. All switches are
>> Honeywell TL series. You will also notice that I changed to a B&C
>> main 60amp
>> alternator and eliminated the low voltage lamp since Dynon will do
>> this on
>> its own. Also, the battery bus only has a cigarette USB plug and a dome
>> light on it. Finally, Bob shows a 20awg wire feeding the E-bus from
>> the main
>> bus which seemed quite small to me. I up sized it to 14awg.
>>
>> (https://flic.kr/p/2h6zWqs)2 (https://flic.kr/p/2h6zWqs) by Jereme
>> Carne (https://www.flickr.com/photos/151084592@N02/), on Flickr
>>
>> On to the buses. Here is the main bus. I also tried to include any
>> future
>> provisions such as the second EFIS even though I don't currently plan
>> it.
>> The IFD-440 however is in the plan and I'm installing a tray for it
>> now. You
>> will also notice the amp numbers on the right side of the
>> description. This is
>> what I could find for MAXIMUM current draw on the device.
>>
>> (https://flic.kr/p/2h6zeK3)main (https://flic.kr/p/2h6zeK3) by
>> Jereme Carne (https://www.flickr.com/photos/151084592@N02/), on Flickr
>>
>> Now the E-bus. I really tried to minimize what I put on this to the
>> essentials but really the end goal was to keep it below 7 ish amps
>> (which is why the xsponder is still there) So far the MAXIMUM
>> current amounts add up to 7.35 amps not including the contactor
>> which is fairly low. (the master at this point would be off so don't
>> worry about that 1 amp) At 2500 engine RPM by the B&C numbers
>> you should get about 7.6 amps. It's also worth noting that in my
>> emergency checklist for this situation I would
>> unplug/turn off everything on the battery bus.
>>
>> (https://flic.kr/p/2h6zeLf)ebus (https://flic.kr/p/2h6zeLf) by
>> Jereme Carne (https://www.flickr.com/photos/151084592@N02/), on Flickr
>>
>> I also am posting the picture of my panel layout if that helps anyone.
>>
>> (https://flic.kr/p/2gV4VSZ)FINAL PANEL (https://flic.kr/p/2gV4VSZ)
>> by Jereme Carne (https://www.flickr.com/photos/151084592@N02/), on
>> Flickr
>>
>>
>> I posted this on another forum first and someone brought up two
>> questions which could probably be answered here.
>>
>> 1. The e-bus is being fed with 2 15 amp fuses (one on the bat bus and
>> one on the e-bus). Is this a mistake?
>> 2. Can someone explain why there is a fusible link and a CB on the
>> alt field circuit?
>>
>> Seriously thanks to everyone who helps me look over this big part of
>> my project. As always if you have questions or comments I welcome it
>> all! :D
>>
> Quickie on the field circuit: The link protects the wire between the
> bus to the breaker; otherwise a short in that wire would see the full
> fury of available current on the bus. The CB is there so the
> overvoltage module can trip it, opening the field circuit, if there's
> an overvoltage fault in the regulator. The field circuit is one of the
> few circuits where you might get a 'false positive' due to a short
> term transient, so a single reset of the protection device could be
> warranted.
>
> Philosophy (at least for most of us on this forum) is that virtually
> all other activations of circuit protection should be analyzed on the
> ground. Any item that's flight-critical should have a backup, meaning
> that troubleshooting (circuit resetting) in flight is unnecessary.
>
> Haven't looked closely at your ebus circuit yet, but a 15A fuse is
> not terribly robust, so a fault on the bus could conceivably blow both
> fuses at once. Not saying to fuse bigger than the wire can stand, but
> you might consider bigger feed wires and/or use circuit protection
> that has a much longer time constant than a fuse (ANL type device, or
> my preference: fusible link).
>
> Welcome aboard!
>
> Charlie
> (like I promised...)
More stuff, as time permits & we see stuff. Apologies if info gets
duplicated from others' posts.
Should have mentioned wire sizes on the field circuit: 'rule of thumb'
around here is keeping wire size to minimum #22, for physical
durability/workability. So #22 fuse link>#18 wire>CB>#20>field. You can
drop to #20 after the CB because a 5A CB will protect #20 wire.
General 'fusing' (circuit protection) thinking: Always remember what the
devices are supposed to do, and ask whether they're proper and in the
proper location for the job. ex: Endurance bus feeds. The #13 wire from
the main bus to the endurance bus is unprotected, and fed by a #4 wire.
The 15A fuse at the alt feed point fuses the bus from that source, but
its job is to protect the *wire*, so it should be at the other end of
the wire. (Which means that it's not needed; you already have a 15A fuse
at the main bat bus (source) *and another* 15A fuse at the bat
contactor, feeding the main bat bus.) I'd consider using a fuse link at
the bat contactor to protect #14 wire, and ask whether you really need
additional fusing on the path to the endurance bus. Logic: Even if a
catastrophic failure takes out the link, the only extra losses would be
your dome light & cigarette plug.
Oh yeah; might be a good idea to ponder future actual use of the
cigarette plug. Most lighter sockets are set up for much higher currents
than 5A. One thing I've used mine for is 'quick & dirty' ground power
(plane is wired differently from your diagram, allowing the cig socket
to power the main bus without powering up the master contactor). If you
ever think you'll need to charge the battery through the cig socket,
upsizing that wire & fuse might be worth considering.
Current shunts: My purchased -6 has one (rarely reads correctly due to
flaky fuse holders); my under-construction -7 will not have any. I was
an electronics tech in several previous lives, and very rarely saw any
use for an ammeter unless I was troubleshooting/repairing an
already-failed device. Trying to use one while literally 'on the fly'
makes zero sense to me. Devices in an a/c will either work correctly or
they won't. Current variations are way down the list of possible
troubleshooting methods to find a defective device while in flight
(like, don't even try). Flight critical devices should have backups;
non-flight-critical ones are...non-critical.
Charlie
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| Subject: | Re: ARINC Wiring Shield? |
Do a web search for FAA Report DOT/FAA/CT 86/40, Aircraft Electromagnetic Compatibility"
and review discussions on shielding. Section 3.3.1 deals with shielding
ARINC 429 signal wires.
The doc is somewhat dated now, having come out after the first generation of airplanes
making heaving use of the ARINC 429 protocol were certified. Its been
a foundational document in developing design and analysis assumptions (at least
in large transport category airplanes). The principles remain valid even in
the age of AFDX/ARINC 664 ethernet based protocols.
I personally wouldn't want want to spend the energy justifying (if even only to
myself) deviating from installation recommendations in this matter.
John
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=491123#491123
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| Subject: | Re: Z-13/8 review request |
On 8/29/2019 1:12 PM, Charlie England wrote:
> On 8/28/2019 10:56 PM, Charlie England wrote:
>> On 8/28/2019 10:22 PM, jcarne wrote:
>>> <jeremejcarne@gmail.com>
>>>
>>> Hello everyone, first time poster here. I would love it if you guys
>>> would review my Z-13/8. Thanks in advance!
>>>
>>> This diagram is Bob's Z-13/8 with VERY FEW modifications. I'll point
>>> them out in the pics below.
>>>
>>> First here are the pics, sorry they are so big but I'm thinking this
>>> is the only way you will be able to read anything.
>>>
>>> I am aware of how to size wires per AC 43.13. However, I went with
>>> what the manufacturer recommended instead
>>> (which was always bigger than AC43.13 or right on). This is why I
>>> have at times two different gauges for the same circuit size.
>>> Yes I know in most instances I can use 22 awg where I speced 20
>>> awg. I already have plenty of both sizes so no worry there.
>>>
>>> Would you all mind taking some time to look it over for any blatant
>>> errors? Mega thank you for taking the time.
>>>
>>> First up is the top of the diagram where the backup B&C SD-8 is.
>>> The changes here are the shunt and ANL positions. I have already
>>> installed two ANL fuses on my firewall as I would prefer both battery
>>> and alternator lines be protected. Many find it unnecessary which may
>>> be the case but it's already done and installed. I have also
>>> removed the
>>> shunt for the backup alternator because if I am ever running on it I
>>> will
>>> know my e-bus is sized right for the current and I can simply
>>> monitor bus
>>> voltage. If you REALLY think I need a shunt give me a good reason
>>> and I
>>> may install one but at this time I don't see the point.
>>>
>>> (https://flic.kr/p/2h6xoGh)1 (https://flic.kr/p/2h6xoGh) by Jereme
>>> Carne (https://www.flickr.com/photos/151084592@N02/), on Flickr
>>>
>>> Next up is the lower meatier part of the diagram. I eliminated the
>>> electronic
>>> ignition and put in for mags instead. I know many like having a
>>> dedicated
>>> start button but I really like the left mag also being your start
>>> switch. This method
>>> is also wired such that the right mag must be off to send power to
>>> the starter. As far as
>>> mag switches and the batt/alt switch they are locking toggles. The
>>> mags lock in off and
>>> on with momentary up. The batt/alt switch locks in all three
>>> positions. All switches are
>>> Honeywell TL series. You will also notice that I changed to a B&C
>>> main 60amp
>>> alternator and eliminated the low voltage lamp since Dynon will do
>>> this on
>>> its own. Also, the battery bus only has a cigarette USB plug and a
>>> dome
>>> light on it. Finally, Bob shows a 20awg wire feeding the E-bus from
>>> the main
>>> bus which seemed quite small to me. I up sized it to 14awg.
>>>
>>> (https://flic.kr/p/2h6zWqs)2 (https://flic.kr/p/2h6zWqs) by Jereme
>>> Carne (https://www.flickr.com/photos/151084592@N02/), on Flickr
>>>
>>> On to the buses. Here is the main bus. I also tried to include any
>>> future
>>> provisions such as the second EFIS even though I don't currently
>>> plan it.
>>> The IFD-440 however is in the plan and I'm installing a tray for it
>>> now. You
>>> will also notice the amp numbers on the right side of the
>>> description. This is
>>> what I could find for MAXIMUM current draw on the device.
>>>
>>> (https://flic.kr/p/2h6zeK3)main (https://flic.kr/p/2h6zeK3) by
>>> Jereme Carne (https://www.flickr.com/photos/151084592@N02/), on Flickr
>>>
>>> Now the E-bus. I really tried to minimize what I put on this to the
>>> essentials but really the end goal was to keep it below 7 ish amps
>>> (which is why the xsponder is still there) So far the MAXIMUM
>>> current amounts add up to 7.35 amps not including the contactor
>>> which is fairly low. (the master at this point would be off so
>>> don't worry about that 1 amp) At 2500 engine RPM by the B&C numbers
>>> you should get about 7.6 amps. It's also worth noting that in my
>>> emergency checklist for this situation I would
>>> unplug/turn off everything on the battery bus.
>>>
>>> (https://flic.kr/p/2h6zeLf)ebus (https://flic.kr/p/2h6zeLf) by
>>> Jereme Carne (https://www.flickr.com/photos/151084592@N02/), on Flickr
>>>
>>> I also am posting the picture of my panel layout if that helps anyone.
>>>
>>> (https://flic.kr/p/2gV4VSZ)FINAL PANEL (https://flic.kr/p/2gV4VSZ)
>>> by Jereme Carne (https://www.flickr.com/photos/151084592@N02/), on
>>> Flickr
>>>
>>>
>>> I posted this on another forum first and someone brought up two
>>> questions which could probably be answered here.
>>>
>>> 1. The e-bus is being fed with 2 15 amp fuses (one on the bat bus
>>> and one on the e-bus). Is this a mistake?
>>> 2. Can someone explain why there is a fusible link and a CB on the
>>> alt field circuit?
>>>
>>> Seriously thanks to everyone who helps me look over this big part of
>>> my project. As always if you have questions or comments I welcome
>>> it all! :D
>>>
>> Quickie on the field circuit: The link protects the wire between the
>> bus to the breaker; otherwise a short in that wire would see the full
>> fury of available current on the bus. The CB is there so the
>> overvoltage module can trip it, opening the field circuit, if there's
>> an overvoltage fault in the regulator. The field circuit is one of
>> the few circuits where you might get a 'false positive' due to a
>> short term transient, so a single reset of the protection device
>> could be warranted.
>>
>> Philosophy (at least for most of us on this forum) is that virtually
>> all other activations of circuit protection should be analyzed on the
>> ground. Any item that's flight-critical should have a backup, meaning
>> that troubleshooting (circuit resetting) in flight is unnecessary.
>>
>> Haven't looked closely at your ebus circuit yet, but a 15A fuse is
>> not terribly robust, so a fault on the bus could conceivably blow
>> both fuses at once. Not saying to fuse bigger than the wire can
>> stand, but you might consider bigger feed wires and/or use circuit
>> protection that has a much longer time constant than a fuse (ANL type
>> device, or my preference: fusible link).
>>
>> Welcome aboard!
>>
>> Charlie
>> (like I promised...)
> More stuff, as time permits & we see stuff. Apologies if info gets
> duplicated from others' posts.
>
> Should have mentioned wire sizes on the field circuit: 'rule of thumb'
> around here is keeping wire size to minimum #22, for physical
> durability/workability. So #22 fuse link>#18 wire>CB>#20>field. You
> can drop to #20 after the CB because a 5A CB will protect #20 wire.
>
> General 'fusing' (circuit protection) thinking: Always remember what
> the devices are supposed to do, and ask whether they're proper and in
> the proper location for the job. ex: Endurance bus feeds. The #13 wire
> from the main bus to the endurance bus is unprotected, and fed by a #4
> wire. The 15A fuse at the alt feed point fuses the bus from that
> source, but its job is to protect the *wire*, so it should be at the
> other end of the wire. (Which means that it's not needed; you already
> have a 15A fuse at the main bat bus (source) *and another* 15A fuse at
> the bat contactor, feeding the main bat bus.) I'd consider using a
> fuse link at the bat contactor to protect #14 wire, and ask whether
> you really need additional fusing on the path to the endurance bus.
> Logic: Even if a catastrophic failure takes out the link, the only
> extra losses would be your dome light & cigarette plug.
>
> Oh yeah; might be a good idea to ponder future actual use of the
> cigarette plug. Most lighter sockets are set up for much higher
> currents than 5A. One thing I've used mine for is 'quick & dirty'
> ground power (plane is wired differently from your diagram, allowing
> the cig socket to power the main bus without powering up the master
> contactor). If you ever think you'll need to charge the battery
> through the cig socket, upsizing that wire & fuse might be worth
> considering.
>
> Current shunts: My purchased -6 has one (rarely reads correctly due to
> flaky fuse holders); my under-construction -7 will not have any. I was
> an electronics tech in several previous lives, and very rarely saw any
> use for an ammeter unless I was troubleshooting/repairing an
> already-failed device. Trying to use one while literally 'on the fly'
> makes zero sense to me. Devices in an a/c will either work correctly
> or they won't. Current variations are way down the list of possible
> troubleshooting methods to find a defective device while in flight
> (like, don't even try). Flight critical devices should have backups;
> non-flight-critical ones are...non-critical.
>
> Charlie
Oh, forgot: You can reduce the number of failure points in the primary
alt B lead path by moving its ANL tie point to the shunt side of the
other ANL. As drawn, the alt current must pass through both ANLs, and
all their related terminals, to get to the airframe's B+ circuit. Also,
*if* I'm reading the drawing correctly, the shunt in its current (pardon
the pun) position will show you the alt's charge current going into the
battery, but will not show you the total current output from the
alternator. If that's your goal, then nothing wrong with it. But since
the bus feed is before the shunt, the shunt won't see that load.
Remember, during normal ops, the alternator carries *all* the electrical
loads of the a/c; the battery is only supplying current when starting,
or after an alternator failure (or total loads exceed alternator
capacity & output voltage drops below battery voltage).
Charlie
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| Subject: | Re: Z-13/8 review request |
>
> to the breaker; otherwise a short in that wire would see the full fury
> of available current on the bus. The CB is there so the overvoltage
> module can trip it, opening the field circuit, if there's an overvoltage
> fault in the regulator. The field circuit is one of the few circuits
> where you might get a 'false positive' due to a short term transient, so
> a single reset of the protection device could be warranted.
>
> Philosophy (at least for most of us on this forum) is that virtually all
> other activations of circuit protection should be analyzed on the
> ground. Any item that's flight-critical should have a backup, meaning
> that troubleshooting (circuit resetting) in flight is unnecessary.
>
> Haven't looked closely at your ebus circuit yet, but a 15A fuse is not
> terribly robust, so a fault on the bus could conceivably blow both fuses
> at once. Not saying to fuse bigger than the wire can stand, but you
> might consider bigger feed wires and/or use circuit protection that has
> a much longer time constant than a fuse (ANL type device, or my
> preference: fusible link).
>
> Welcome aboard!
>
> Charlie
> (like I promised...)
>
> ---
> This email has been checked for viruses by Avast antivirus software.
> https://www.avast.com/antivirus
Ok I don't think I can quote multiple posts at once. If that is not the case I
would love to hear how to do it.
That description on the field circuit makes sense now Charlie. I am also in the
camp that troubleshooting should be done on the ground. This is a big part
of why I'm using fuses instead of CBs. I did not change the two 15 amp fuses
to feed the e-bus from what Bob has drawn. The e-bus will be no more than 7-8
amps so I'm not sure up sizing is needed. However, I am by no means an expert
here, I simply went with what Bob had on the drawing in that location.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=491125#491125
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| Subject: | Re: Z-13/8 review request |
user9253 wrote:
> Two 15 amp fuses are not a mistake. Suppose that a short circuit blows the
> battery fuse. Now what is going to stop high current from flowing through the
diode?
> I agree with you that a shunt is not needed. An ammeter is good for
> troubleshooting. But fly the plane and save troubleshooting until on the
> ground. The EFIS voltmeter is all that is needed to tell if the alternator is
working or not.
> I agree with Charlie that the 15 amp fuses are too small. When two fuses
> are in series (main fuse and branch fuse), a hard short circuit could blow both
> unless there is a very large difference in fuse sizes. Having fuses in series
is usually not a good idea.
> The ANL fuse for the main power bus is an unnecessary failure point. But
> since you have already installed it, insulate it well. Try to eliminate potential
> sparks after a forced landing.
Ok I think I put out some confusion on the whole 15 amp fuse deal so let me lay
it out more clearly.
Now that I look at my drawing there is actually 3 15 amp fuses to feed the E-bus.
I added in an inline fuse between the battery and the battery bus. My reasoning
being that I AM NOT going to mount my battery bus on the firewall but instead
inside the cockpit, therefor I felt it necessary to protect the wire which
will be longer than 6 inches. Now the way Bob has it drawn in one of his
versions is off of the battery bus there is a 15 amp fuse that feeds to the e-bus
where another 15 amp fuse connects the feed to the e-bus. That being said,
I am all ears if there is a better way of doing this or if I simply need to
upsize all them fuses? Could a guy not just do a fusible link off the battery
side of the master relay instead of the 15 amp inline? This may be a better
approach here.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=491126#491126
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| Subject: | Re: Z-13/8 review request |
jim(at)PoogieBearRanch.co wrote:
> Jereme,
>
> I'm a complete novice when it comes to the actual electronics involved,
> so I'll leave it to Bob and the other experts to comment on those
> aspects.
>
> But I did notice on the e-bus diagram that your GPS is NOT wired to the
> e-bus. If you're flying IFR (or at night), wouldn't the ability to
> navigate be fairly critical at that point? Personally, I think I'd want
> that on the e-bus, but maybe I'm nuts...
>
> I also noticed you DO have the Garmin G5 on the e-bus. I'm sure you
> know Garmin offers a backup battery, with up to 4 hours endurance. If
> you include that battery in your plans, could you safely remove the G5
> from the e-bus? I know it's a tiny load, but every little bit helps,
> right?
>
> Jim Parker
It is my understanding that the backup battery I will have on the Skyview will
allow me to still navigate (I'm going to look into the manual on this one though
so don't take my word for it). Is it legal for IFR work, no. If I'm only
running on my e-bus for some reason in IFR do I care about the legality of it,
heck no.
I would love to have the IFD-440 on the e-bus but I think it simply draws too much
current. I'm only able to put about 8 amps on the e-bus.
You are correct on the G5 but I want my attitude indicators to have multiple power
sources if I'm going to fly IFR. It is such a small load that it still seems
worth it to me even despite having a battery backup. However, this is something
I could move if needed.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=491128#491128
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| Subject: | Re: Z-13/8 review request |
The Skyview will allow you to navigate IF you have either the Dynon 250
or 2020 GPS installed as its primary GPS source driving its moving map.
Totally selectable between Dynon GPS and IFD for navigation.
On 8/29/2019 5:15 PM, jcarne wrote:
>
> >
> It is my understanding that the backup battery I will have on the Skyview will
allow me to still navigate (I'm going to look into the manual on this one though
so don't take my word for it). Is it legal for IFR work, no. If I'm only
running on my e-bus for some reason in IFR do I care about the legality of it,
heck no.
>
> I would love to have the IFD-440 on the e-bus but I think it simply draws too
much current. I'm only able to put about 8 amps on the e-bus.
>
> You are correct on the G5 but I want my attitude indicators to have multiple
power sources if I'm going to fly IFR. It is such a small load that it still
seems worth it to me even despite having a battery backup. However, this is something
I could move if needed.
>
>
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=491128#491128
>
>
>
>
>
>
>
>
>
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| Subject: | Re: Z-13/8 review request |
> Charlie
> Oh, forgot: You can reduce the number of failure points in the primary
>
> alt B lead path by moving its ANL tie point to the shunt side of the
> other ANL. As drawn, the alt current must pass through both ANLs, and
> all their related terminals, to get to the airframe's B+ circuit. Also,
> *if* I'm reading the drawing correctly, the shunt in its current (pardon
> the pun) position will show you the alt's charge current going into the
> battery, but will not show you the total current output from the
> alternator. If that's your goal, then nothing wrong with it. But since
> the bus feed is before the shunt, the shunt won't see that load.
> Remember, during normal ops, the alternator carries *all* the electrical
> loads of the a/c; the battery is only supplying current when starting,
> or after an alternator failure (or total loads exceed alternator
> capacity & output voltage drops below battery voltage).
>
> Charlie
>
> ---
> This email has been checked for viruses by Avast antivirus software.
> https://www.avast.com/antivirus
Yes this is one thing I have gona back and forth on. It was either make the current
from the alternator go through two ANL devices to charge the battery or
only 1 to feed the bus. I'm not sure I follow the reduction in failure points.
If you take the alt b lead to the shunt side of the lower ANL won't that result
in the alt b lead having to go through two ANL devices to feed the bus?
If the lower ANL tripped or failed wouldn't that also result in no battery or
primary alt power to the bus?
The shunt in the current position is what I intended when I installed it. In the
end I don't really see the shunt as that valuable of a tool so I'll keep it
where it is I suppose.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=491130#491130
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| Subject: | Re: Z-13/8 review request |
Kellym wrote:
> The Skyview will allow you to navigate IF you have either the Dynon 250
> or 2020 GPS installed as its primary GPS source driving its moving map.
> Totally selectable between Dynon GPS and IFD for navigation.
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=491128#491128
>
>
>
[/quote]
Kelly, thanks for the clarification. I will be running their GPS-2020
Read this topic online here:
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| Subject: | Re: Z-13/8 review request |
Ok I saved this one for last as there is a lot of GREAT info in this one Charlie.
>
> duplicated from others' posts.
>
> Should have mentioned wire sizes on the field circuit: 'rule of thumb'
> around here is keeping wire size to minimum #22, for physical
> durability/workability. So #22 fuse link>#18 wire>CB>#20>field. You can
> drop to #20 after the CB because a 5A CB will protect #20 wire. (understood)
>
> General 'fusing' (circuit protection) thinking: Always remember what the
> devices are supposed to do, and ask whether they're proper and in the
> proper location for the job. ex: Endurance bus feeds. The #13 wire from
> the main bus to the endurance bus is unprotected, and fed by a #4 wire. (I'm
a bit confused on this last sentence. The main bus to e-bus feeder is 14 awg
(which I upsized from Bob's 20awg as it seemed a bit small to me). If this is
a mistake let me know.)
> The 15A fuse at the alt feed point fuses the bus from that source, but
> its job is to protect the *wire*, so it should be at the other end of
> the wire. (Which means that it's not needed; you already have a 15A fuse
> at the main bat bus (source) *and another* 15A fuse at the bat
> contactor, feeding the main bat bus.) I'd consider using a fuse link at
> the bat contactor to protect #14 wire, and ask whether you really need
> additional fusing on the path to the endurance bus. Logic: Even if a
> catastrophic failure takes out the link, the only extra losses would be
> your dome light & cigarette plug. Ya you have summed up my confusion on this
one pretty well. I am now thinking fuselink at the battery contactor but figured
Bob had some sort of reason for the two fuses between the two buses.
>
> Oh yeah; might be a good idea to ponder future actual use of the
> cigarette plug. Most lighter sockets are set up for much higher currents
> than 5A. One thing I've used mine for is 'quick & dirty' ground power
> (plane is wired differently from your diagram, allowing the cig socket
> to power the main bus without powering up the master contactor). If you
> ever think you'll need to charge the battery through the cig socket,
> upsizing that wire & fuse might be worth considering. Oh how interesting, hadn't
thought of that. I will ponder that one.
>
> Current shunts: My purchased -6 has one (rarely reads correctly due to
> flaky fuse holders); my under-construction -7 will not have any. I was
> an electronics tech in several previous lives, and very rarely saw any
> use for an ammeter unless I was troubleshooting/repairing an
> already-failed device. Trying to use one while literally 'on the fly'
> makes zero sense to me. Devices in an a/c will either work correctly or
> they won't. Current variations are way down the list of possible
> troubleshooting methods to find a defective device while in flight
> (like, don't even try). Flight critical devices should have backups;
> non-flight-critical ones are...non-critical. Totally agree, at this point I
think the shunt is only there since I already have it installed.
>
> Charlie
>
> ---
> This email has been checked for viruses by Avast antivirus software.
> https://www.avast.com/antivirus
For anyone else that is interested here is my firewall and what I have to work
with. There is a lot of time in "fireproofing" this bad boy which is why I'm
not wanting to change anything on it.
(https://flic.kr/p/TiyRKL)firewall (https://flic.kr/p/TiyRKL) by Jereme Carne (https://www.flickr.com/photos/151084592@N02/), on Flickr
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=491132#491132
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| Subject: | Re: Z-13/8 review request |
Answers inserted; formatting is weird because I still get the list via
email.
On 8/29/2019 7:56 PM, jcarne wrote:
>
> Ok I saved this one for last as there is a lot of GREAT info in this one Charlie.
>
>
>> duplicated from others' posts.
>>
>> Should have mentioned wire sizes on the field circuit: 'rule of thumb'
>> around here is keeping wire size to minimum #22, for physical
>> durability/workability. So #22 fuse link>#18 wire>CB>#20>field. You can
>> drop to #20 after the CB because a 5A CB will protect #20 wire. (understood)
>>
>> General 'fusing' (circuit protection) thinking: Always remember what the
>> devices are supposed to do, and ask whether they're proper and in the
>> proper location for the job. ex: Endurance bus feeds. The #13 wire from
>> the main bus to the endurance bus is unprotected, and fed by a #4 wire. (I'm
a bit confused on this last sentence. The main bus to e-bus feeder is 14 awg
(which I upsized from Bob's 20awg as it seemed a bit small to me). If this
is a mistake let me know.)
>> The 15A fuse at the alt feed point fuses the bus from that source, but
>> its job is to protect the *wire*, so it should be at the other end of
>> the wire. (Which means that it's not needed; you already have a 15A fuse
>> at the main bat bus (source) *and another* 15A fuse at the bat
>> contactor, feeding the main bat bus.) I'd consider using a fuse link at
>> the bat contactor to protect #14 wire, and ask whether you really need
>> additional fusing on the path to the endurance bus. Logic: Even if a
>> catastrophic failure takes out the link, the only extra losses would be
>> your dome light & cigarette plug.
>> Ya you have summed up my confusion on this one pretty well. I am now thinking
fuselink at the battery contactor but figured Bob had some sort of reason for
the two fuses between the two buses.
I confess I hadn't pulled up z13-8 to see the original configuration.
Looking at it now, I think Bob's logic is: #14 from bat contactor to bat
bus is unfused because of 6" rule; it would need protection (fuselink?)
if the bat bus is remoted, as you thought. I think the 'ebus15A' fuse
feeding S704-1>etc protects the downstream wire (other side of relay)
from the battery. The #20 fuselink from endur-bus to that wire protects
the wire from current supplied through the diode from the main bus. I
confess I don't know why he used #20 link to protect #14 wire, unless
he's looking at protecting the #16 going to the main bus. I missed the
6" rule for the main>endur-bus wire; no need for protection if 6" rule
is observed in your install.
>>
>>
>> Oh yeah; might be a good idea to ponder future actual use of the
>> cigarette plug. Most lighter sockets are set up for much higher currents
>> than 5A. One thing I've used mine for is 'quick & dirty' ground power
>> (plane is wired differently from your diagram, allowing the cig socket
>> to power the main bus without powering up the master contactor). If you
>> ever think you'll need to charge the battery through the cig socket,
>> upsizing that wire & fuse might be worth considering.
>> Oh how interesting, hadn't thought of that. I will ponder that one.
>> Current shunts: My purchased -6 has one (rarely reads correctly due to
>> flaky fuse holders); my under-construction -7 will not have any. I was
>> an electronics tech in several previous lives, and very rarely saw any
>> use for an ammeter unless I was troubleshooting/repairing an
>> already-failed device. Trying to use one while literally 'on the fly'
>> makes zero sense to me. Devices in an a/c will either work correctly or
>> they won't. Current variations are way down the list of possible
>> troubleshooting methods to find a defective device while in flight
>> (like, don't even try). Flight critical devices should have backups;
>> non-flight-critical ones are...non-critical.
>> Totally agree, at this point I think the shunt is only there since I already
have it installed.
>>
>>
>> Charlie
>>
>> ---
>> This email has been checked for viruses by Avast antivirus software.
>> https://www.avast.com/antivirus
>
> For anyone else that is interested here is my firewall and what I have to work
with. There is a lot of time in "fireproofing" this bad boy which is why I'm
not wanting to change anything on it.
>
> (https://flic.kr/p/TiyRKL)firewall (https://flic.kr/p/TiyRKL) by Jereme Carne (https://www.flickr.com/photos/151084592@N02/), on Flickr
>
Message 15
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| Subject: | Re: Z-13/8 review request |
On 8/29/2019 7:37 PM, jcarne wrote:
>
>
>> Charlie
>> Oh, forgot: You can reduce the number of failure points in the primary
>>
>> alt B lead path by moving its ANL tie point to the shunt side of the
>> other ANL. As drawn, the alt current must pass through both ANLs, and
>> all their related terminals, to get to the airframe's B+ circuit. Also,
>> *if* I'm reading the drawing correctly, the shunt in its current (pardon
>> the pun) position will show you the alt's charge current going into the
>> battery, but will not show you the total current output from the
>> alternator. If that's your goal, then nothing wrong with it. But since
>> the bus feed is before the shunt, the shunt won't see that load.
>> Remember, during normal ops, the alternator carries *all* the electrical
>> loads of the a/c; the battery is only supplying current when starting,
>> or after an alternator failure (or total loads exceed alternator
>> capacity & output voltage drops below battery voltage).
>>
>> Charlie
>>
>> ---
>> This email has been checked for viruses by Avast antivirus software.
>> https://www.avast.com/antivirus
>
> Yes this is one thing I have gona back and forth on. It was either make the
current from the alternator go through two ANL devices to charge the battery or
only 1 to feed the bus. I'm not sure I follow the reduction in failure points.
If you take the alt b lead to the shunt side of the lower ANL won't that
result in the alt b lead having to go through two ANL devices to feed the bus?
If the lower ANL tripped or failed wouldn't that also result in no battery or
primary alt power to the bus?
>
> The shunt in the current position is what I intended when I installed it. In
the end I don't really see the shunt as that valuable of a tool so I'll keep
it where it is I suppose.
>
>
You're right; I got a little cross-eyed looking across the split in the
print. :-) You do still have the issue of only measuring battery charge
current, omitting measurement of bus loads from measurement. The z13-8
design has the bus fed directly from the master contactor, so the shunt
measures all alternator output. Your choice on how to wire that, but
even the FAA considers the master contactor to be protection for the bus
wire.
Z13-8 protects the shunt in addition to the alt B-lead by placing the
protection at the battery end (start contactor) of the B-lead. Remember,
the alternator can't hurt the wire; we're protecting the wire (and
shunt) from the battery. I just use a soldered-in fuselink for the
B-lead, with no shunt, eliminating the multiple failure points created
by the shunt terminals & shunt.
I confess that I really like soldered-in fuselinks, in places that will
only blow after a (low probability) catastrophic fault. I trust my
soldering (old school electronics tech) more than any other connection
method for areas that should never need to be touched again.
Charlie
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| Subject: | Re: Z-13/8 review request |
>
> You're right; I got a little cross-eyed looking across the split in the
> print. :-) You do still have the issue of only measuring battery charge
> current, omitting measurement of bus loads from measurement. The z13-8
> design has the bus fed directly from the master contactor, so the shunt
> measures all alternator output. Your choice on how to wire that, but
> even the FAA considers the master contactor to be protection for the bus
> wire.
>
> Z13-8 protects the shunt in addition to the alt B-lead by placing the
> protection at the battery end (start contactor) of the B-lead. Remember,
> the alternator can't hurt the wire; we're protecting the wire (and
> shunt) from the battery. I just use a soldered-in fuselink for the
> B-lead, with no shunt, eliminating the multiple failure points created
> by the shunt terminals & shunt.
>
> I confess that I really like soldered-in fuselinks, in places that will
> only blow after a (low probability) catastrophic fault. I trust my
> soldering (old school electronics tech) more than any other connection
> method for areas that should never need to be touched again.
>
> Charlie
Haha no worries Charlie. I think you have gotten through my thick skull on this
one. I was unaware that the ANL fuses are really there to protect from the
battery (although I am aware that circuit protection is for the wiring). In addition,
you are correct on the shunt placement and what it measures. I don't
see the need to have bus current other than a "cool" factor but maybe I'm wrong.
So this leads me to three possibilities that I would like to run by you. As I
understand it right now I will have a shunt that is unprotected from the battery
as well as more failure points in the unprotected string (seems like an extremely
low risk in my mind but I'm electron challenged and it's still a risk nevertheless)
Here are the options (that I can think of):
1. Keep my setup as is (in the firewall pic I sent previously) and install a
hall effect sensor on the bus feed line if I really wanted feeder current. This
still leaves the shunt unprotected from the battery.
2. Eliminate the shunt as shown on my firewall and either move it or install a
hall effect sensor upstream of my ANL limiters. This method would seem to solve
most of it but will leave two blank bolts on my firewall and require a longer
copper bar to connect my contactor to the ANL limiters.
3. Wire/run bar to my ANL limiters and then take the main bus feed off of the
shunt. This methoud would probably be the easiest but it would look weird and
the placement of the two ANL devices and shunt would look weird.
Anyways, let me know what you think.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=491136#491136
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