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What size for a ground wire from a terminal strip?

Steve Crewdog

Well Known Member
Patron
Got a bunch of ground wires from various avionics pieces running to a terminal strip, all individually under 7 amp draw, then to a larger ground stud between the engine -> battery negative. (SeaRey airframe is aluminum and cannot be used as a ground.) Just want to double check that-to a point- the ground wire size does not matter, I was going to use a 16ga wire from the terminal strip to the stud, about 30" away.


Thoughts?


Thanks
 
Wire size does matter! .. how may of those "7 amp" wires are you routing to the terminal block, and how much net current to do expect going to from the block to the battery ground point? All outgoing current on the + leads comes back on the ground returns (to first order) .. so it need to be sized appropriately.

Take a look at the following:

http://www.aeroelectric.com/articles/wiresize.pdf

16 AWG is sized at ~12A continuous without getting too hot (per the temperature rise spec ~35 deg C) ... if you're dumping alot more current to ground than that, a larger gauge wire is in order.
 
Wire size does matter! .. how may of those "7 amp" wires are you routing to the terminal block, and how much net current to do expect going to from the block to the battery ground point? All outgoing current on the + leads comes back on the ground returns (to first order) .. so it need to be sized appropriately.

Take a look at the following:

http://www.aeroelectric.com/articles/wiresize.pdf

16 AWG is sized at ~12A continuous without getting too hot (per the temperature rise spec ~35 deg C) ... if you're dumping alot more current to ground than that, a larger gauge wire is in order.

Got it. Thank you, sir. Nothing on it will be running at max load at the same time, but just readded all the devices grounded, most of them are low amperage LED warning lights and total is only 9amp, but just to be sure I'm switching to 10ga.
 
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