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FOT grounding via separate wire to Batt/firewall

Acenels

Active Member
Looking to validate my thought here (or invalidate).

I'm reworking my avionics, and adding a forest of tabs (FOT) for my grounds. I am going to put the FOT on the subpanel. The subpanel is grounded to the airframe. However, to ease the flow of electrons I planned to add a number 8 wire from the FOT to the battery connection on the firewall rather than mounting directly on the firewall (where the post goes through the firewall to the grounding strap).

Will this cause any problems as it gives the ground two route back home (1/ though the wire or 2/ through the airframe)?

Is it overkill, dumb, or otherwise a bad idea?

Currently the avionics are grounded to the airframe on the canopy rail via octopus of tongue connectors. As I am going to a mostly glass setup--g3x but keeping EI instrumentation for engine--I want to take the opportunity to make the electrical system a little cleaner. I could put the FOT on the firewall, but that would severely limit access compared to the sub panel. But if it would be a huge performance difference, I would go that route.
 
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Pretty typical to have a FOT on the firewall with a through-bolt. from the engine side to the battery with a large battery cable. I see no problem with having a jumper from the FOT to a cable to a bolt to another cable. Mostly wanting a separate route with avionics only.
 
Vern's GBX-25A

Perhaps have a look at Vern Little's GBX-25A - no idea if he's still making them, but I used one on my panel and it was very helpful. Double ground to the FOT, which is on the airframe. The FW ground is for the battery and the two engine grounds for the starter.

https://vansairforce.net/community/showthread.php?t=66343

IMG_4320-1-1024x1024.jpeg
 
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