Today's Message Index:
----------------------
0. 06:47 PM - [PLEASE READ] Why I Have A Fund Raiser... (Matt Dralle)
1. 05:15 AM - Re: Interesting panel voltmeter (Sebastien S)
2. 10:55 AM - Re: RV-10 Electrical Review with Electric AC and FlyEFII (johnbright)
3. 11:43 AM - Re: RV-10 Electrical Review with Electric AC and FlyEFII (Charlie England)
4. 05:23 PM - Re: RV-10 Electrical Review with Electric AC and FlyEFII (Charlie England)
5. 06:14 PM - out of town for a few days (Robert L. Nuckolls, III)
6. 06:46 PM - Re: RV-10 Electrical Review with Electric AC and FlyEFII (melstien)
7. 07:42 PM - Re: out of town for a few days (Christopher Cee Stone)
8. 07:51 PM - Re: Re: RV-10 Electrical Review with Electric AC and FlyEFII (Sebastien S)
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| Subject: | [PLEASE READ] Why I Have A Fund Raiser... |
Since the beginning, the Matronics List and Forum experience has been free from
advertising. I have been approached by fair number of vendors wanting to tap
into the large volume of activity across the various lists hosted here, but have
always flatly refused. Everywhere you go on the Internet these days, a user
is pummeled with flashing banners and videos and ads for crap that they don't
want. Yahoo, Google and that ilk are not "free". The user must constantly
endure their barrage of commercialism thrust into their face at an ever increasing
rate. Enough is enough, and the Lists at Matronics choose not to succumb
to that.
That being said, running a service of this size is not "free". It costs a lot
of money to maintain the hardware, pay for the electricity, Commercial-greade
Internet Connection, air conditioning, maintenance contracts, etc, etc. etc.
I choose to hold a PBS-like fund raiser each year during the month of November
where I simply send out a short email every other day asking the members to make
a small contribution to support the operation. That being said, that contribution
is completely voluntary and non-compulsory. Many members choose not
to contribute and that's fine.
However, a very modest percentage of the members do choose to make a contribution
and it is that financial support that keeps the Lists running. And that's
it. To my way of thinking, it is a much more pleasant way of maintaining the
Lists and Forums. The other 11 months of the year, you don't see a single advertisement
or request for support. That's refreshing and that is a List and Forum
that I want to belong to. I think other people feel the same way.
Won't you please take a minute to make your Contribution today and support these
Lists?
https://matronics.com/contribution
Or, drop a personal check in the mail to:
Matt Dralle / Matronics
581 Jeannie Way
Livermore CA 94550
USA
Thank you for your support!
Matt Dralle
Email List Admin.
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| Subject: | Re: Interesting panel voltmeter |
I replaced my analog voltmeter which was vibrating all over the place with o
ne of those and was very pleased with the result. I bought two so that I wou
ld have a spare but years later it was still working perfectly.
> On Nov 9, 2021, at 01:13, Robert L. Nuckolls, III <nuckolls.bob@aeroelectr
ic.com> wrote:
>
> =EF=BB
>
> Ran across this product while searching a solution
> for a client:
>
> https://tinyurl.com/yeedoayu
>
> Got one in today. Accuracy is very good. Current draw
> is 0.015A, mounting simple . . . back nut installation
> thru single hole. Small size.
>
> Price is right too.
>
> Bob . . .
>
> Un impeachable logic: George Carlin asked, "If black boxes
> survive crashes, why don't they make the whole airplane
> out of that stuff?"
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| Subject: | Re: RV-10 Electrical Review with Electric AC and FlyEFII |
Some quick thoughts re RV-10 Dual Battery - Dual Alternator rev 2.0 schematic:
Excellent you put a rev level on your schematic.
Be cautious about unintended consequences of altering Z schematics. An FMEA is
in order; FWIW mine is called Failure Analysis and is in Engineering Basic Stuff
folder at https://drive.google.com/drive/folders/1u6GeZo6pmBWsKykLNVQMvu4o1VEVyP4K?usp=sharing
Complying with FAR 23.1361 Master Switch Arrangement is desirable
also.
With a 40A air contidioner, total load could sag the main alternator and cause
total field current to both alternators to trip a 5A breaker; as pointed out earlier,
that CB is an SOP for both alternators so separate CBs are called for
anyway.
Engine bus:
FYI for context my plan is SDS EFI+I on a Lycoming four cylinder.
Excellent that you put each fuel pump, coilpack, and injector on it's own feed
and eliminated the automatic fuel pump relay; these are SOPs in the EFII System
32 install manual.
I believe a 10A fuse/CB for a fuel pump is OK but I take SDS' recommendation of
15A fuse for a pump and 10A fuse for a coilpack.
I calculate 14.2A for a four-cylinder SDS system at low altitude, a six-cylinder
system will add a coilpack and two injectors resulting in 15.9A. I imagine EFII
brand SDS brand current draws are close to one another. Ref Load Analysis
in Engineering Basic Stuff folder, same link as above.
You could use 10 awg to the engine bus.
Question: With EFII brand EFI+I, if you lose one coilpack, does your six cylinder
engine become a four cylinder?
The latest B&C LR3, rev D (LR3D), will drive an LED. LR3C will drive an LED as
shown in a Bob Nuckolls' sketch; when I google "LR3_LV_Led_1.jpg" it's the top
result.
BTW FYI the terminal "OV Sense", in addition to being the V sense for the crowbar,
is also the V sense for the regulator.
--------
John Bright, RV-6A, at FWF, O-360
Z-101 single batt dual alt SDS EM-5-F.
john_s_bright@yahoo.com, Newport News, Va
https://drive.google.com/folderview?id=1u6GeZo6pmBWsKykLNVQMvu4o1VEVyP4K
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=504049#504049
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| Subject: | Re: RV-10 Electrical Review with Electric AC and FlyEFII |
On 11/8/2021 5:10 PM, melstien wrote:
>
> Hello,
>
> I am looking to finalize my electrical system prior to running wires and electronics.
>
> Mission - IFR cross country trips with my wife around the US
>
> Airplane Specifics:
> -RV-10
> -BPE IO-540 D4A5 with 9:1 compression
> -Fly EFII System 32 with dual controller and electronic injection and ignition
> -BnC Primary belt driven alternator and controller
> -BnC rear spline driven alternator and controller
> -VPX-Pro to run most electronics, the engine will not be on the VPX Pro
> -Electric Air Conditioner 12 volts DC at 40 Amps Max
> -Electronics are all Garmin 2 screen with GTN750, audio panel, second radio,
remote transponder, and 3 axis autopilot
> -IBBS batteries (qty2) to keep critical flight electronics running when -Master(s)
are turned off
> -Batteries planned to be in rear as per plans (Earthx ETX900) qty 2 planned.
> -Fly LED works Package plus one extra dual LED landing light in the cowing
>
> Summary of electrical schematic: I have leveraged the Z101 architecture and
added a second battery and master switch for it, mostly for separate Air Conditioner
control and second battery charging/isolation. The AC connection is a
relay or contactor and is on the hot side of the second battery master. This
was done to isolate the second battery from all other ships power when needed,
like when running AC on the ground or during take-off and landing operations.
During flight I can turn on the second master, re-charge the second battery,
run the AC off the alternator and have the extra capacity available if needed
for emergency flight ops.
>
> Alternators: Only one will be providing power at any one time. The second
one on the vac pad will be set to a lower voltage and will only output power
when the primary alternator voltage goes low or craps out. I may not have the
sense wire or field wires correctly connected. I wish to have them both active/standby
at the same time. Can one switch do this or is it best to have two
switches?
>
> Loads. The engine will require 11 Amps at full load to run the dual ECUs, 6
injectors and 3 quad coil packs and misc. engine instruments, according the manufacturer.
I have individual fused power wires from each injector and each
coil going to the engine bus.
> One EarthX ETX900 will run a 16 amp load for close to 60 minutes.
>
> Mission critical electronics will be powered in an emergency from the IBBS batteries
if no other power is available.
>
> I do have a hot buss that is used only for some minor items.
>
> Example of emergency: Fire/smoke in the cockpit- both masters off, fuel off.
Engine gets really quite. Select location and turn to it for landing and
stabilize the aircraft in a best glide. Smart glide will be useful. If needed
and if advisable, I could turn on the Emergency engine power switch and energize
the engine bus. The engine buss isolated from the main power feeds using
diodes.
>
>
> I have read many discussions about the EFI systems vs mechanical/traditional
systems. I am not asking for feedback on that aspect unless there is new information
or facts that can contribute to the discussion.
>
> One additional idea I was thinking about was to just add the second battery to
the firewall and have it run just the engine in an emergency. The cable runs
will be much shorter and keep everything a bit more location contained. W&B
will be impacted and needs to be considered.
>
> I welcome and appreciate feedback on the design based on my mission.
>
> Michael
Hi Michael,
Some stuff I'd look at:
The ETX900 is rated at 16AH. While lithium tech does better at
maintaining voltage deep into discharge than lead-acid, the AH rating is
still real. I wouldn't trust one to supply 16A for an hour when it was
brand new, and I certainly wouldn't expect it when the battery has some
age on it. Might not be an issue with dual alternators, but I wouldn't
plan on a full hour without alternator power.
Smoke/fire: My choice with my electronic injection engine is to have a
totally separate engine bus, with its own switching, and a 'cross-tie'
switch from the main airframe bus as the power source backup. I have one
alt tied to the main bus and the other alt tied to the engine bus. My
process for smoke will be to 1st shut off the airframe (leaves the
engine running, just like carb/mags system). If still smoke, *then* shut
down the engine bus and pray for a landing spot.
Circuit protection: Like Joe said, setting circuit protection anywhere
near the potential demand of the load is inviting 'nuisance trips',
which get a lot bigger than nuisance level if it's the engine. I chose
to use a soldered-in fusible link for the primary supply on the engine
bus feed from the battery. I did the same as you on the injectors/coils,
but I'm seriously considering going to fusible links there, too.
I'd consider that 11A figure for engine amps somewhat optimistic, based
on typical fuel pump & injector power consumption. I'd verify before
trusting.
VPX Pro: Can't address the VPX brand directly from memory, but there are
some electronic control boxes on the market that have multiple 'single
points of failure' inherent in their design that can shut down
everything attached to them. Might be worth a deep dive, especially for
an IFR platform.
I've never had the luxury of air conditioning in an a/c, but IIRC,
certified stuff specs turning it off for takeoff. Have you run the
numbers on how much it will suck out of one of those 16AH batteries
while running battery-only, and what the lithium battery will do to
alternator output if it's significantly discharged when it's tied back
into the system? I think I've read accounts of the smaller EX battery
drawing 50-60 amps, if it was even slightly discharged when it came on line.
Alternators: I don't see circuit protection shown at the feed from the
battery(s), and both alt B leads are tied together at the dual diodes
feeding the engine bus. Any fault on any B lead could take out both alts.
I might have misinterpreted or misread some stuff; if I did I apologize.
Charlie
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| Subject: | Re: RV-10 Electrical Review with Electric AC and FlyEFII |
On 11/9/2021 1:47 PM, Charlie England wrote:
> On 11/8/2021 5:10 PM, melstien wrote:
>>
>> Hello,
>>
>> I am looking to finalize my electrical system prior to running wires
>> and electronics.
>>
>> Mission - IFR cross country trips with my wife around the US
>>
>> Airplane Specifics:
>> -RV-10
>> -BPE IO-540 D4A5 with 9:1 compression
>> -Fly EFII System 32 with dual controller and electronic injection and
>> ignition
>> -BnC Primary belt driven alternator and controller
>> -BnC rear spline driven alternator and controller
>> -VPX-Pro to run most electronics, the engine will not be on the VPX Pro
>> -Electric Air Conditioner 12 volts DC at 40 Amps Max
>> -Electronics are all Garmin 2 screen with GTN750, audio panel, second
>> radio, remote transponder, and 3 axis autopilot
>> -IBBS batteries (qty2) to keep critical flight electronics running
>> when -Master(s) are turned off
>> -Batteries planned to be in rear as per plans (Earthx ETX900) qty 2
>> planned.
>> -Fly LED works Package plus one extra dual LED landing light in the
>> cowing
>>
>> Summary of electrical schematic: I have leveraged the Z101
>> architecture and added a second battery and master switch for it,
>> mostly for separate Air Conditioner control and second battery
>> charging/isolation. The AC connection is a relay or contactor and is
>> on the hot side of the second battery master. This was done to
>> isolate the second battery from all other ships power when needed,
>> like when running AC on the ground or during take-off and landing
>> operations. During flight I can turn on the second master,
>> re-charge the second battery, run the AC off the alternator and have
>> the extra capacity available if needed for emergency flight ops.
>>
>> Alternators: Only one will be providing power at any one time.
>> The second one on the vac pad will be set to a lower voltage and will
>> only output power when the primary alternator voltage goes low or
>> craps out. I may not have the sense wire or field wires correctly
>> connected. I wish to have them both active/standby at the same
>> time. Can one switch do this or is it best to have two switches?
>>
>> Loads. The engine will require 11 Amps at full load to run the dual
>> ECUs, 6 injectors and 3 quad coil packs and misc. engine instruments,
>> according the manufacturer. I have individual fused power wires
>> from each injector and each coil going to the engine bus.
>> One EarthX ETX900 will run a 16 amp load for close to 60 minutes.
>>
>> Mission critical electronics will be powered in an emergency from the
>> IBBS batteries if no other power is available.
>>
>> I do have a hot buss that is used only for some minor items.
>>
>> Example of emergency: Fire/smoke in the cockpit- both masters off,
>> fuel off. Engine gets really quite. Select location and turn to
>> it for landing and stabilize the aircraft in a best glide. Smart
>> glide will be useful. If needed and if advisable, I could turn on
>> the Emergency engine power switch and energize the engine bus. The
>> engine buss isolated from the main power feeds using diodes.
>>
>>
>> I have read many discussions about the EFI systems vs
>> mechanical/traditional systems. I am not asking for feedback on
>> that aspect unless there is new information or facts that can
>> contribute to the discussion.
>>
>> One additional idea I was thinking about was to just add the second
>> battery to the firewall and have it run just the engine in an
>> emergency. The cable runs will be much shorter and keep everything a
>> bit more location contained. W&B will be impacted and needs to be
>> considered.
>>
>> I welcome and appreciate feedback on the design based on my mission.
>>
>> Michael
> Hi Michael,
> Some stuff I'd look at:
> The ETX900 is rated at 16AH. While lithium tech does better at
> maintaining voltage deep into discharge than lead-acid, the AH rating
> is still real. I wouldn't trust one to supply 16A for an hour when it
> was brand new, and I certainly wouldn't expect it when the battery has
> some age on it. Might not be an issue with dual alternators, but I
> wouldn't plan on a full hour without alternator power.
>
> Smoke/fire: My choice with my electronic injection engine is to have a
> totally separate engine bus, with its own switching, and a 'cross-tie'
> switch from the main airframe bus as the power source backup. I have
> one alt tied to the main bus and the other alt tied to the engine bus.
> My process for smoke will be to 1st shut off the airframe (leaves the
> engine running, just like carb/mags system). If still smoke, *then*
> shut down the engine bus and pray for a landing spot.
>
> Circuit protection: Like Joe said, setting circuit protection anywhere
> near the potential demand of the load is inviting 'nuisance trips',
> which get a lot bigger than nuisance level if it's the engine. I chose
> to use a soldered-in fusible link for the primary supply on the engine
> bus feed from the battery. I did the same as you on the
> injectors/coils, but I'm seriously considering going to fusible links
> there, too.
>
> I'd consider that 11A figure for engine amps somewhat optimistic,
> based on typical fuel pump & injector power consumption. I'd verify
> before trusting.
>
> VPX Pro: Can't address the VPX brand directly from memory, but there
> are some electronic control boxes on the market that have multiple
> 'single points of failure' inherent in their design that can shut down
> everything attached to them. Might be worth a deep dive, especially
> for an IFR platform.
>
> I've never had the luxury of air conditioning in an a/c, but IIRC,
> certified stuff specs turning it off for takeoff. Have you run the
> numbers on how much it will suck out of one of those 16AH batteries
> while running battery-only, and what the lithium battery will do to
> alternator output if it's significantly discharged when it's tied back
> into the system? I think I've read accounts of the smaller EX battery
> drawing 50-60 amps, if it was even slightly discharged when it came on
> line.
>
>
> Alternators: I don't see circuit protection shown at the feed from the
> battery(s), and both alt B leads are tied together at the dual diodes
> feeding the engine bus. Any fault on any B lead could take out both alts.
>
> I might have misinterpreted or misread some stuff; if I did I apologize.
>
> Charlie
followup/edit:
Just noticed the ANLs drawn next to the alternators. They need to be at
the battery-end of the B leads; not at the alts. Electrically it *looks*
the same, but the physical location matters. The danger to the wire is
from the battery. The wire should be sized large enough to handle
anything the alternator (which is self-limiting at slightly above rated
amps) can throw at it, but the battery can throw hundreds (a thousand?)
of amps at the wire.
I think Joe mentioned the 15A CB that feeds the engine bus. Another
concern with it would be that if you for any reason lose the B lead
connection to the main bus, it looks like that feeder would be the path
from alts to the main bus. If that's the case, loss of the main B lead
would put you on battery power if alt output exceeds CB rating by very much.
One thing I've seen recommended is to play 'what if' with any proposed
wiring diagram. Likely worthwhile to build a spreadsheet while doing it.
The process is to pick a wire, open it, and ask what happens; is it a
problem, and what alternative is available to work around it. Then short
it to ground and ask the same questions. Repeat for each wire in the
diagram. It will usually reveal issues & limitations in the diagram.
Charlie
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| Subject: | out of town for a few days |
Dr. Dee and I are attending the EAA Hall of Fame banquet on
Nov 11 in OSH. Not taking a computer with me . . . Dr. Dee
sez this is a 'cheese and beer shopping' trip. I do get to
talk shop at the banquet . . .
Aye aye Captain!
See you in a few days.
Bob . . .
Un impeachable logic: George Carlin asked, "If black boxes
survive crashes, why don't they make the whole airplane
out of that stuff?"
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| Subject: | Re: RV-10 Electrical Review with Electric AC and FlyEFII |
Hello John,
Yes, I like to keep track of my changes so I try to add revision tags. I don't
always remember.
I will take a look at the failure modes and probably better align this to the Z101
and also try to organize it so it makes physical sense. That will also allow
me to see where all my connection points should be. Currently it is just
electrically correct (or will be if people suggest good changes)
I will add separate filed switches on the alternators. I was not sure and that
was one of my questions.
The 40 Amp AC will be an experiment. I do not plan to add it to the alternator
load except during level flight at altitude and near an airport. AC is a luxury.
The Earthex batteries can draw at least 100 amps continuously so I think
they will pick up any sag and my IBBS batteries on critical avionics are also
meant to do that as well.
Engine Bus answers:
6 Cylinder as opposed to a 4 cylinder
Yes, everything will have its own power lead and the coil packs will have a fusable
link and a breaker
Injectors will have a fusible link only
I planned to not have the pump on automatice failover but to run them both during
takeoff, landing and fuel tank switch-overs but Robert at FLYEFII did not suggest
that. he thought it might cause cavitation on the inlet. My testing
using my actual fuel lines and pressure regulator indicated that running both
at the same time more than doubled the current draw (4.9 amps per pump solo) and
the fule flow increased marginally. I think they were both fighting each
other to supply pressure at the pump outlet and it was still only going through
qty 1 -3/8 inch hose.
I had thought about splicing each injector wire and coil pack power feed into 2
wires and feeding them off Engine Bus A and engine Bus B all with diode isolation.
The schematic looked cool but it introduced to many connections points
which would probably have increased failures.
FLYEFII suggests a 10 Amp fuse for the for the pumps and my load testing indicates
they only use 4.9 when run separately. I can review the wires size I used
and see if it will support a 12 or 15 amp breaker.
FlyEFII did not state what the coil pack would need when powered separately. They
have the coil packs and the injectors all being fed by 1 15 amp fuse. I
suspect that the coil packs will still need a 15 amp fuse per coil pack because
they all charge at different times, so splitting them into 3 does not reduce
the peak current, just the frequency it occurs. (I am a Mech Engineer so I am
looking for guidance on that.) I have reached out to FLY EFII and requested
guidance.
FlyEFII informed me that the system at high RPM will consume 11 AMPs. That is
all I have to go on. to meet my 1 hour of reserve, I can always move up the
ETX 1200 battery. Its the same form factor and will carry an 18 amp load for
80 minutes. If that is not enough there is always the ETX1600 (120Amp/hours).
Even two of the 1200's weight less than 1 PC680. Money is just the issue.
Not a place to skimp.
Regarding the coil packs, cylinder 1-4 are spread across coil packs A and B so
they are redundant. If you lose A or B you still have 1 working plug per cylinder
1-4. FLY EFII added the 3rd coil pack and both plugs for cylinders 5
and 6 are on the same pack. I have informed FLYEFII that I would suggest a
different arrangement so both plugs were not on the same coil pack. I do know
of a person who lost coil pack C and the engine ran without too much vibration,
but I need to check into that story.
I have 2 LR3Ds and the higher output backup alternator. I just noticed they come
with an amber light. I will ties these outputs into my EFIS but a good light
is also nice. I Prefer LED for lower heat and better vibration and longer
life.
OV Sense, so this is the contact that senses the buss voltage and is used to increase
or decrease the voltage ouput? I have them both going to the Main Bus,
but maybe the backup should go to the engine bus. There is a possibility the
main bus has power but the engine bus does not. Your thoughts?
I reviewed your diagram and it is really what I intended mine to be, only with
the second battery.
Thanks for the feedback. I appreciate it.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=504060#504060
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| Subject: | Re: out of town for a few days |
A well deserved award awaits... My hat is off to you for your tireless
efforts to educate and elucidate!
cheers!
rv8iator
On Tue, Nov 9, 2021 at 6:17 PM Robert L. Nuckolls, III <
nuckolls.bob@aeroelectric.com> wrote:
>
> Dr. Dee and I are attending the EAA Hall of Fame banquet on
> Nov 11 in OSH. Not taking a computer with me . . . Dr. Dee
> sez this is a 'cheese and beer shopping' trip. I do get to
> talk shop at the banquet . . .
>
> Aye aye Captain!
>
> See you in a few days.
>
> Bob . . .
>
> Un impeachable logic: George Carlin asked, "If black boxes
> survive crashes, why don't they make the whole airplane
> out of that stuff?"
>
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| Subject: | Re: RV-10 Electrical Review with Electric AC and |
FlyEFII
Hello Michael,
Im currently debugging a FLYEFII install on a Murphy Rebel. The fuel pumps are
definitely a conundrum. Fuel pump dependant aircraft are nothing new and for a
century the solution has been to run both the primary and the backup pump during
critical phases of flight. This doesnt seem to work well with the FLYEFII
system so they have that relay to enable only one pump at a time. If you install
their Bus Manager it includes a circuit to keep an eye on the fuel pressure
and switch to the backup pump if necessary. Without this system I see only two
options:
1. Create your own monitoring and automatic switching system,
2. Run both pumps during critical phases of flight. This will require careful testing
since it might cause problems in an effort to avoid a potentially catastrophic
one.
As for your second battery, I would suggest putting it in the front. Youll need
to be careful not to overheat it and youll end up carrying ballast in the baggage
compartment when light, but when heavy youll have more useful load.
> On Nov 9, 2021, at 18:49, melstien <michael@elstien.us> wrote:
>
>
> Hello John,
>
> Yes, I like to keep track of my changes so I try to add revision tags. I don't
always remember.
>
> I will take a look at the failure modes and probably better align this to the
Z101 and also try to organize it so it makes physical sense. That will also
allow me to see where all my connection points should be. Currently it is just
electrically correct (or will be if people suggest good changes)
>
> I will add separate filed switches on the alternators. I was not sure and
that was one of my questions.
>
> The 40 Amp AC will be an experiment. I do not plan to add it to the alternator
load except during level flight at altitude and near an airport. AC is a
luxury. The Earthex batteries can draw at least 100 amps continuously so I think
they will pick up any sag and my IBBS batteries on critical avionics are
also meant to do that as well.
>
> Engine Bus answers:
> 6 Cylinder as opposed to a 4 cylinder
> Yes, everything will have its own power lead and the coil packs will have a fusable
link and a breaker
> Injectors will have a fusible link only
> I planned to not have the pump on automatice failover but to run them both during
takeoff, landing and fuel tank switch-overs but Robert at FLYEFII did not
suggest that. he thought it might cause cavitation on the inlet. My testing
using my actual fuel lines and pressure regulator indicated that running both
at the same time more than doubled the current draw (4.9 amps per pump solo)
and the fule flow increased marginally. I think they were both fighting each
other to supply pressure at the pump outlet and it was still only going through
qty 1 -3/8 inch hose.
> I had thought about splicing each injector wire and coil pack power feed into
2 wires and feeding them off Engine Bus A and engine Bus B all with diode isolation.
The schematic looked cool but it introduced to many connections points
which would probably have increased failures.
>
> FLYEFII suggests a 10 Amp fuse for the for the pumps and my load testing indicates
they only use 4.9 when run separately. I can review the wires size I used
and see if it will support a 12 or 15 amp breaker.
>
> FlyEFII did not state what the coil pack would need when powered separately.
They have the coil packs and the injectors all being fed by 1 15 amp fuse.
I suspect that the coil packs will still need a 15 amp fuse per coil pack because
they all charge at different times, so splitting them into 3 does not reduce
the peak current, just the frequency it occurs. (I am a Mech Engineer so I
am looking for guidance on that.) I have reached out to FLY EFII and requested
guidance.
>
> FlyEFII informed me that the system at high RPM will consume 11 AMPs. That
is all I have to go on. to meet my 1 hour of reserve, I can always move up
the ETX 1200 battery. Its the same form factor and will carry an 18 amp load
for 80 minutes. If that is not enough there is always the ETX1600 (120Amp/hours).
Even two of the 1200's weight less than 1 PC680. Money is just the issue.
Not a place to skimp.
>
> Regarding the coil packs, cylinder 1-4 are spread across coil packs A and B so
they are redundant. If you lose A or B you still have 1 working plug per
cylinder 1-4. FLY EFII added the 3rd coil pack and both plugs for cylinders
5 and 6 are on the same pack. I have informed FLYEFII that I would suggest
a different arrangement so both plugs were not on the same coil pack. I do
know of a person who lost coil pack C and the engine ran without too much vibration,
but I need to check into that story.
>
> I have 2 LR3Ds and the higher output backup alternator. I just noticed they
come with an amber light. I will ties these outputs into my EFIS but a good light
is also nice. I Prefer LED for lower heat and better vibration and longer
life.
>
> OV Sense, so this is the contact that senses the buss voltage and is used to
increase or decrease the voltage ouput? I have them both going to the Main Bus,
but maybe the backup should go to the engine bus. There is a possibility
the main bus has power but the engine bus does not. Your thoughts?
>
> I reviewed your diagram and it is really what I intended mine to be, only with
the second battery.
>
> Thanks for the feedback. I appreciate it.
>
>
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=504060#504060
>
>
>
>
>
>
>
>
>
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