tenbear wrote:
It seems to be generally agreed that it is best to install the switch in the negative lead. The reason for this is that if somehow a wire, tool, etc gets on the positive wiring no harm is done. If the negative post is somehow grounded the only bad effect is to connect the battery to the usual circuitry.
If the positive is disconnected and something, wire etc, contacts the positive terminal and the chassis, it could cause lots of damage.
Although I wouldn't disagree with this explanation I would disagree that most do it this way and instead install it in the positive lead, just as I always do, as I've never been concerned about "accidental grounding". :)