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  #251  
Old 06-20-2018, 04:39 AM
BillL BillL is offline
 
Join Date: Sep 2007
Location: Central IL
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Default A good reminder before first flight, or the next flight.

Quote:
Originally Posted by rv6ejguy View Post
There was a fatal accident with our EFI installed on an Egg 6 engine a number of years back, which I helped the TSB up here investigate since they were unfamiliar with these engines or EFI. After going over the obvious, I found the cause in about 15 minutes for the power loss. Injector power was mis-wired to the wrong breaker value (adjacent breaker). In this case a 3 amp one.

It did not show up in extensive ground running as the rpms did not get quite as high as they did with the prop unloaded a bit in flight (current draw a bit higher at higher rpms). Engine stopped at about 300 feet after takeoff and a landing was attempted on the crossing runway. Stall/spin and my friend test flying, was killed.

As Dan said, this is vitally important stuff.

For Vertical Power users, please read our warnings about setting breakers values on these devices when using our EFI.
During checkout I found a cross wired breaker on my professionally wired panel. It can happen, this is a good point for the commissioning of a new aircraft, that is to check every breaker to ensure it is properly connected as designed and expected.
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RV-7
Lord Kelvin:
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and express it in numbers, you know something about it; but when you
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  #252  
Old 06-20-2018, 05:50 AM
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DanH DanH is offline
 
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Location: 08A
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I previously asked about wiring diagrams (post 93):

Quote:
In the meantime, it sure would be nice to see a complete wiring diagram for a dual EM-5. This one seems to be missing all the details for injector switching:

http://www.sdsefi.com/dualecu4.pdf

John Bright's notes state that injector switching is different for SDS and EFII installations. Robert doesn't seem to have published a diagram for his version of the EM, or for the System 32.
The SDS diagram linked above is partial, and doesn't cover the 6-cyl models. As noted, there does not seem to be any published diagram for EFII versions, which were supplied with a different harness. Both vendors supply a marked harness, and builders are expected to connect it as indicated on the tags.

Ultimately the builder is responsible for how the aircraft is wired. No available diagrams makes wiring difficult to evaluate, prior to purchase, or during installation when changes might be considered.

Considering only injectors for the moment, we can see individual circuit protection for the injectors on the SDS diagram. We have learned that some significant number of EFII installations are wired with a single 10 amp breaker for two coils and four injectors, but the vendor is or was evaluating individual supplies.

What we don't see is the ground control side of the injector circuits. Each injector's ground is opened and closed by the ECU to establish pulse width. So, a question. Does the supplied harness combine (junction) all the injector grounds, then run a single wire to the ECU (via switching relays, if dual ECU), or does the harness provide individual individual grounds all the way to the relays or ECU?
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  #253  
Old 06-20-2018, 06:39 AM
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rv6ejguy rv6ejguy is offline
 
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Location: Calgary, Canada
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Quote:
Originally Posted by DanH View Post
I previously asked about wiring diagrams (post 93):

Considering only injectors for the moment, we can see individual circuit protection for the injectors on the SDS diagram. We have learned that some significant number of EFII installations are wired with a single 10 amp breaker for two coils and four injectors, but the vendor is or was evaluating individual supplies.

What we don't see is the ground control side of the injector circuits. Each injector's ground is opened and closed by the ECU to establish pulse width. So, a question. Does the supplied harness combine (junction) all the injector grounds, then run a single wire to the ECU (via switching relays, if dual ECU), or does the harness provide individual individual grounds all the way to the relays or ECU?
On aircraft installations, we supply wiring with twin ground path connections to the ECU (pins 8 and 16 on white ECU connector). These should go to separate terminals and either one is sufficient to run all circuits concerned.

On 4 cylinder dual ECU setups, the injector relays have their own ground. Relay is normally closed for primary ECU control so no ground or power is required in that mode.
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Turbo Subaru EJ22, SDS EFI, Marcotte M-300, IVO, Shorai- RV6A C-GVZX flying from CYBW since 2003- 441.0 hrs. on the Hobbs,
RV10 95% built- Sold 2016
http://www.sdsefi.com/aircraft.html
http://sdsefi.com/cpi2.htm


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  #254  
Old 06-20-2018, 07:00 AM
rvsxer rvsxer is offline
 
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Quote:
Originally Posted by DanH View Post
Both vendors supply a marked harness, and builders are expected to connect it as indicated on the tags.

Ultimately the builder is responsible for how the aircraft is wired.
Exactly. Here at SteinAir, we get many requests to modify the wiring scheme from what Ross and Robert Paisley specify in their instructions, and we, as a matter of policy, don't do it. If we do, and it doesn't work as it should, we assume some responsibility for it, which we are not willing to do. There are a number of ways to insure an uninterrupted power supply to the system, and it is indeed up to our customers to decide how and to provide it.

The bottom line for us: Alternative ignition and fuel delivery systems are here to stay. We gladly accommodate them for our customers, but we must insist the designers' instructions be followed.
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  #255  
Old 06-21-2018, 05:03 AM
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DanH DanH is offline
 
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Quote:
Originally Posted by rv6ejguy View Post
On aircraft installations, we supply wiring with twin ground path connections to the ECU (pins 8 and 16 on white ECU connector). These should go to separate terminals and either one is sufficient to run all circuits concerned.
Thanks, I was thinking about the injector leads. Found it in the manual.

Quote:
Originally Posted by rvsxer View Post
There are a number of ways to insure an uninterrupted power supply to the system, and it is indeed up to our customers to decide how and to provide it.

The bottom line for us: Alternative ignition and fuel delivery systems are here to stay. We gladly accommodate them for our customers, but we must insist the designers' instructions be followed.
I don't think anyone blames the panel guys for the SQ-12 engine out. They did what they should, and probably what you would do...they got advice in writing, and built it.
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  #256  
Old 06-21-2018, 11:33 AM
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rcpaisley rcpaisley is offline
 
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Default wiring

Let's be very clear here:

We have published, recommended, and tested wiring layouts for our systems.
All of our harnesses are CLEARLY labelled with the recommended breaker values on each power leg. There are people who decide to implement their own versions of wiring in their 'experimental' aircraft. This is something we can not control.

This in no way means that we recommend custom installations, that we have tested these installations or that they are in any way known to work or not work. Once you start re-inventing the wheel, it's on you to test it to make sure it works. We can only control what happens inside our shop, not what happens in the rest of the world. We get into conversations with customers all the time about their custom wiring installations. This doesn't turn a custom installation into recommended or tested wiring.

Follow manufacture recommendations! Your manufacturers know more about their systems than anyone else. Be very careful about following the advise or conclusions of Internet trolls - typing 'Google' does not give someone experience in a subject, and it does not make them an expert.

Robert
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  #257  
Old 06-22-2018, 06:41 AM
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DanH DanH is offline
 
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Quote:
Originally Posted by rcpaisley View Post
Once you start re-inventing the wheel, it's on you to test it to make sure it works.
It is always the builder's responsibility, even when installing exactly as the vendor suggests. There is no reason to assume anyone (vendor, troll, best buddy, or A&P-IA) is correct. Trust, but verify.

Robert, will the System 32 harness be supplied with a single circuit protection device for coils and injectors, like past harness, or individual circuit protection for each device?
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  #258  
Old 06-22-2018, 11:42 AM
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rcpaisley rcpaisley is offline
 
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Default S32 harness

System32 harnesses have fusible links in the harness on all 12v supply wires.
Each injector and each coil pack power lead is individually protected.
The breaker requirement does not change. If a coil pack were to short out, it would pop its fusible link and not affect anything else. If an injector power lead were to short out, it would pop the fusible link for only that one injector.
The fusible links are located in the engine side circular connector backshell.

Robert
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  #259  
Old 06-22-2018, 12:31 PM
rv7charlie rv7charlie is offline
 
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So, where can we view the schematic? Or at least, the wiring diagram?
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  #260  
Old 06-22-2018, 02:48 PM
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DanH DanH is offline
 
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Quote:
Originally Posted by rcpaisley View Post
System32 harnesses have fusible links in the harness on all 12v supply wires.
Each injector and each coil pack power lead is individually protected.
The breaker requirement does not change. If a coil pack were to short out, it would pop its fusible link and not affect anything else. If an injector power lead were to short out, it would pop the fusible link for only that one injector.
The fusible links are located in the engine side circular connector backshell.
Robert
Thank you Robert. A tidy solution; my compliments sir.
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