Forum Discussion

IBcarguy's avatar
IBcarguy
Explorer
May 22, 2016

12V

In trailer 12volt applications, white is positive and black negative right?
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    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.
  • IBcarguy wrote:
    In trailer 12volt applications, white is positive and black negative right?


    If you are talking about the leads coming off of the battery that's the way mine is wired, maybe the rest of the rig too but I haven't looked that close at it. Kind of confusing if you ask me. Now you have me thinking about it.

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