SDS EM5 / EM 6 Electrical + VPX Pro Question

[1001001]

Can anyone out there who has installed an SDS EM5 or EM6 system (ignition and fuel injection) please share how they split up/grouped the various electrical users? I'm especially interested in how you've integrated it with a VP-X Pro system.

I have been planning on a CPI-2 ignition with traditional fuel injection (already have the FI system with my engine), but have recently been thinking about going with the full EM6 EFI/EI system. I'd like to know how others have laid out their electrical systems. The EM6 installation manual calls out a need for a total of 18 circuit breakers and 7 switches for a 6-cylinder dual ECU system, which is obviously not easily do-able with a VPX without fused sub-buses. I would, in any case, likely power the EFI/FI system (at least half of it) independently from the VP-X anyway.

Also interested in how you have designed your electrical system for redundancy with the EM5/EM6 system. I'm working from the basis of a friend's RV-10, which has an electrical system based on the Aeroelectric Z-14 diagram, with dual Lightspeed ignitions, with the ignitions powered through breakers directly from each battery via fused "battery buses".

 

[rv6ejguy]

We caution against connecting our components to a VPX since it trips breakers on the basis of peak current rather than average current as a conventional thermal breaker does. The injectors, fuel pumps and ignition coils in particular have very high surge current but relatively low average current. These are flight critical components.

I'll PM you with some info on dual bus resources.

 

[1001001]

We caution against connecting our components to a VPX since it trips breakers on the basis of peak current rather than average current as a conventional thermal breaker does. The injectors, fuel pumps and ignition coils in particular have very high surge current but relatively low average current. These are flight critical components.

I'll PM you with some info on dual bus resources.

Thanks Ross. In your EM6 installation manual, the circuit count table shows "breakers," but in the circuit diagram, fuses are shown--I presume certain things would benefit from resettable breakers, such as the fuel pumps and maybe injectors, that are highly critical and might benefit from a single reset attempt in an emergency.

What is your thinking on this? I presume from the diagram that there are not redundant circuits to each injector.

 

[rv6ejguy]

Fuse or breakers. Your preference.

 

[agent4573]

Our entire plane is wired through the VPX Pro except the SDS. On the right side we added 16 physical breakers for SDS and one or two other critical power functions. It wasn't ideal to have to put physical breakers into a full "modern" panel, but the reasoning behind it makes sense, and we were out of pins on the VPX anyway so it worked out nicely.

 

[dmattmul]

As with most users with energy dependent engines routed everything but circuits that supply engine power through the VPX. For my panels (14 and 10) this was 8 circuits not powered through the VPX. My injectors are fused but not on the panel. My logic was if an injector tripped a fuse it was a waste of precious time trying to reset an injector CB. (This is not knocking those who decide having a C/B in the panel for injectors is a bad idea) Using 2 batteries (Earth X ETX-900's), 2 alternators and dual busses both running at 14.2 volts. B leads since amperage both busses and of course monitor voltage. So far (Almost 550 hrs. system has performed well). It's a good idea to thoroughly evaluate your design with these types of engines. Safe flying!!