Designing this for an IFR RV-10 with SDS EFI.
I started off with Nuckoll's Z-101 design combined with Leok's diagram I found on VAF. I had initially intended to go with dual alt and 1 battery and adapted the Z-101 design to this:
But it looked like however unlikely it may be, a battery failure would result in the alternator keeping everything online, and while it should be more than capable of the task, if the alternator had a hiccup or something like that there is no way to bring the backup or primary alternator back online.
So I moved on to adapt the design I had into a dual battery dual alt design like this:
This should allow the engine electronics to remain powered no matter battery or alternator failure, and also provides a way to energize the backup alt in the scenario of a VP-X failure. I moved everything off of the E-bus in the second design as I intend to use an ETX900 as the primary and an ETX680 as the secondary, so either should have enough capacity to keep the main bus fed for 20-30 minutes and I can leisurely shed load through the VP-X if I need to.
One thing that I need to add to these diagrams is diodes on the two backup alternator field wires.
Interested in any feedback or suggestions.
I started off with Nuckoll's Z-101 design combined with Leok's diagram I found on VAF. I had initially intended to go with dual alt and 1 battery and adapted the Z-101 design to this:
But it looked like however unlikely it may be, a battery failure would result in the alternator keeping everything online, and while it should be more than capable of the task, if the alternator had a hiccup or something like that there is no way to bring the backup or primary alternator back online.
So I moved on to adapt the design I had into a dual battery dual alt design like this:
This should allow the engine electronics to remain powered no matter battery or alternator failure, and also provides a way to energize the backup alt in the scenario of a VP-X failure. I moved everything off of the E-bus in the second design as I intend to use an ETX900 as the primary and an ETX680 as the secondary, so either should have enough capacity to keep the main bus fed for 20-30 minutes and I can leisurely shed load through the VP-X if I need to.
One thing that I need to add to these diagrams is diodes on the two backup alternator field wires.
Interested in any feedback or suggestions.
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