Battery Power - Electrical Specs

[andya]

Have been searching the electrical dwgs and the parts book most of the afternoon. I am trying to determine what size wire they used for the starter. Any help appreciated. Was it aluminum or copper?
if aluminum what size copper can you replace it with. I remember a PIPER SB covering converting to copper wires from battery in some airplanes but can't find that either.

thanks

[taildraggerpilot]

You can use 4 ga. pretty successfully and most people do. When I got my field approval for installing a master relay in my pacer, I used 4 ga. However, during my recent rebuild, I upped both the starter wire and battery ground wires to 2 ga. If you go to the Aeroelectric website, he has quite a lot of info on this and he typically recommends 4 ga. for most applications. The Pacer/Tripacer's have a fairly short run so you don't have much voltage drop. If the battery were in the tail it would be a different story.

I worked with Bob of Aeroelectric at Beech a couple years ago and spoke with him at length about this. He told me 4 ga. was fine, but it certainly wouldn't hurt to go up to 2 ga., so I did.

Bob's website is: http://www.aeroelectric.com/
It's a very good resource and I have learned a lot. He also has a book out on various aircraft electrical topics and it is very resourceful as well.