Gauging the wire....
For my forthcoming dual 6V set-up (replacing the original 12V "dual purpose" battery that came with the RV) I'll need to add the "series" wire connection between the two. Would 4-gauge be big enough f...
Forum Discussion
Wire size is determined by current carrying requirements (and acceptable voltage drop), regardless of where the wire is. For a short jumper between batteries, the voltage drop is rarely much of a great concern as the length of the wire is short and so the overall resistance low.
If you go with the same size as your power and ground wires, as others have said, you will be fine assuming they have been appropriately sized. If you have more than one of either of them, it's the aggregate cross-sectional area that probably should be considered. Alternately, if you can readily determine the maximum current you'll see, that can also be a good guide. One example of this might be if there's a large fuse or circuit breaker inline with the battery; you can be pretty sure that the maximum current draw will not exceed that fuse or breaker's rating, and size based on that.
If the cost is not excessive and you have the room, there's nothing at all wrong with choosing a larger size than necessary.
If you go with the same size as your power and ground wires, as others have said, you will be fine assuming they have been appropriately sized. If you have more than one of either of them, it's the aggregate cross-sectional area that probably should be considered. Alternately, if you can readily determine the maximum current you'll see, that can also be a good guide. One example of this might be if there's a large fuse or circuit breaker inline with the battery; you can be pretty sure that the maximum current draw will not exceed that fuse or breaker's rating, and size based on that.
If the cost is not excessive and you have the room, there's nothing at all wrong with choosing a larger size than necessary.
