EXCERPT from book:  RVing For Newbies – The Manual (published 2/7/2022)

There are at a minimum 4 colors of electrical wiring, for most applications, now some things like thermostats have others but here are the basic ones, (in no order as you will see below):

 

Black Red White Green or Bare Copper

Here in lies a confusion about RV electricity and wires:

  • 120V AC (30-amp/15-amp)
    • Black = Hot, the wire carrying power
    • White = Neutral
    • Copper/Green = Ground
  • 120V AC (50-amp)
    • Black = Hot, the wire carrying power
    • Red = Hot, the other wire carrying power
    • White = Neutral
    • Copper/Green = Ground
  • 12V DC
    • Red = Hot, the wire carrying power
    • Black = Ground or below
  • 12V DC
    • Black = Hot, the wire carrying power
    • White = Ground

You can see how in one environment black wire is hot (120V AC) and the other environment black is ground (12V DC).   In the section on fuses(in the book), you will read about a story on how this caused an issue for someone, thankfully they didn’t fry their converter/RV battery charger, it just blew two 40 amp fuses there to protect it.

Here is more where the confusion comes in, depending on which RV manufacturer did the wiring, the wires to the 12V DC battery, it could be it has red/black or black/white wiring.  This means, if you have red/black, red is on positive and black is on negative, but if you have black/white, black goes to positive and white goes to negative.

See how this can mess people up very easily and cause people to wire things up backwards, so it is always best to take a picture of what the wires look like BEFORE removing them from the battery.