IBcarguy wrote:
In trailer 12volt applications, white is positive and black negative right?
No, Voltmeter is needed to test.. here is why:
In the world of Electronics, and this includes automotive world. BLACK is normally either earth ground, chassis ground or both.. Please note that this does NOT mean negative,,, it means ground (Electronics often use both PLUS and MINUS voltages In fact your desktop computer power supply has several outputs some are negative voltage)
But RV's are not wired by folks like me (Trained electronics tech) they are wired by ELECTRICANS.. The same folks who wire a sticks and bricks
And to them Black is "HOT" and White is Neutral.
On the 12 volt side of life "HOT" is Positive
So, the bottom line is without a volt meter or other polarity tester you can not be sure which is which
Suggestion... While the batteries are properly hooked up get a can of Testor's spray paint.. Red, or a bottle of red nail polish, and paint all the POSITIVE wires. All of them..
Optional ... Black on the negative wires.. but that is optional.