Positive or Negative to Battery switch
Just got my Torx box installed and my battery switch. Wanting to wire it up tomorrow. I believe I know (negative) but thought I would ask do I put the switch on the Neg or pos? Thanks for your help...
Forum Discussion
LittleBill wrote:joshuajim wrote:
Perhaps this will enlighten some folks.
Here
the person who wrote that document should be fired, you need 2 wires to complete a circuit, both sides of the circuit will use the same amount of power. PERIOD.
NPN transistors are primarily used for ground switching as they are not dependent on the voltage of the circuit they are powering, but are able to use the voltage of the micro controller, generally a 3.3v or 5v reference voltage, where as PNP transistors are switched on the positive side and must match that of the circuit they are powering.
i really didn't want to go into that. needless to say everything i said in regards to switching the power on either side changes nothing in regards to arching or amp usage, the general reason they switch ground is the reason i listed above
Yep.
The only thing I'll give the author of that so-called "technical" article is that there is a lower chance of a shorted wire on a load causing maximum AMPS to flow through the computer control transistor if you switch the ground. To do that would mean the wiring shorted to a +12V source. If the +12V side were switched, the wire need only find a ground to short to of which there are plenty on a grounded frame vehicle. Either way, a properly designed system will have fuses that blow before the wiring or control box.
That said, none of this has to do with disconnecting a battery on a trailer.
