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I thought i would write up a couple of things I did slightly different. I chose EFI/EI for the engine, mostly because it is what I know and understand. It does require a reliable electrical system, or it won't be reliable.
I wanted extra battery capacity in case of alternator failure, and I wanted to be able to jump start my own aircraft, or somebody else's. So instead of a full 2 battery system, I bought a big LI-ion jump start pack. It normally resides in an easy to remove mount, plugged into the aircraft for backup-battery use only. No onboard charging allowed. Or it can be removed from its' mount for jumpstarting and charging. It is rated at 21 ah/hour. A "Gotcha" with any lithium battery is the marketing. Many are sold as PB/eq. Or lead equivalent. It will say 15 ah/hr, Pb/eq. That means it will crank like a 15 ah/hr lead battery, but doesn't have the same ah/hr capacity. Usually, it is about 1/3 of that.
I call this "almost 2 batteries". The ships battery and Jump pack should run the engine for 2 hours.
The other "other", is I wanted more redundancy in the alternator. VAF had a great "alternator reliability poll" post on their forum. Very long post. Most alternator failures, like >80%, are actually voltage regulator failures. So I thought instead of a second alternator, maybe just carry a 2nd VR? That morphed into I will mount it next to the 1st VR, and put a connector on both to swap them. Which morphed into putting both of them on switches, which is what I have now. Maybe sometime I will decided I want 2 alternators. If I do, its' VR is already installed.
But for now, I have almost 2 alternators.
VR.jpg
The basic circuit architecture is straight out of Bob Knuckles.
The last thing that is less common than most is I used a "fuse/relay" panel, similar to what cars use. The main advantage is similar to the VPX - it reduces mechanical connections by 2/3. I like the VPX and probably would have used one, but the EFI manufacterer sort of recommended against it. Nothing wrong with them, but they are software controlled, as is the EFI. They are unsure how the two might interact. Spruces sells several models, and those manufacterers have different models. Mine is from Eaton's "Littlefuse" brand.
EFI/EI require more switched/fused circuits than a carb or MFI.
fues:relay.jpg
I wanted extra battery capacity in case of alternator failure, and I wanted to be able to jump start my own aircraft, or somebody else's. So instead of a full 2 battery system, I bought a big LI-ion jump start pack. It normally resides in an easy to remove mount, plugged into the aircraft for backup-battery use only. No onboard charging allowed. Or it can be removed from its' mount for jumpstarting and charging. It is rated at 21 ah/hour. A "Gotcha" with any lithium battery is the marketing. Many are sold as PB/eq. Or lead equivalent. It will say 15 ah/hr, Pb/eq. That means it will crank like a 15 ah/hr lead battery, but doesn't have the same ah/hr capacity. Usually, it is about 1/3 of that.
I call this "almost 2 batteries". The ships battery and Jump pack should run the engine for 2 hours.
The other "other", is I wanted more redundancy in the alternator. VAF had a great "alternator reliability poll" post on their forum. Very long post. Most alternator failures, like >80%, are actually voltage regulator failures. So I thought instead of a second alternator, maybe just carry a 2nd VR? That morphed into I will mount it next to the 1st VR, and put a connector on both to swap them. Which morphed into putting both of them on switches, which is what I have now. Maybe sometime I will decided I want 2 alternators. If I do, its' VR is already installed.
But for now, I have almost 2 alternators.
VR.jpg
The basic circuit architecture is straight out of Bob Knuckles.
The last thing that is less common than most is I used a "fuse/relay" panel, similar to what cars use. The main advantage is similar to the VPX - it reduces mechanical connections by 2/3. I like the VPX and probably would have used one, but the EFI manufacterer sort of recommended against it. Nothing wrong with them, but they are software controlled, as is the EFI. They are unsure how the two might interact. Spruces sells several models, and those manufacterers have different models. Mine is from Eaton's "Littlefuse" brand.
EFI/EI require more switched/fused circuits than a carb or MFI.
fues:relay.jpg
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