Help identifying wires, please

[JRRNeiklot]

I have 3 white wires coming from the junction box under my camper.  They transition into a black wire that ends in a ring terminal.  I have no idea where this wire goes.  I don't know if it's a ground or positive, if it's trailer brakes, or what.  The previous owner has apparently engaged in some redneck engineering.  I'm including a link to a picture, since I can't figure out how to post a pic.  If anyone can help identify these wires, I'd greatly appreciate it.

Thanks.

 

[highdesertranger]

that looks like a trailer wiring junction box. is this a trailer? which means 90% of the time white is ground. however I would make damn sure it's a ground wire before hooking it up. or hook it up temporarily though a test circuit breaker. but first off get out your digital volt/ohm meter and test for continuity to ground. highdesertranger

 

[B and C]

Always check for voltage on a wire before setting it to ohms.

 

[JRRNeiklot]

that looks like a trailer wiring junction box.  is this a trailer?  which means 90% of the time white is ground.  however I would make damn sure it's a ground wire before hooking it up.  or hook it up temporarily though a test circuit breaker.  but first off get out your digital volt/ohm meter  and test for continuity to ground.  highdesertranger

Yes.  It's a travel trailer.

 

[Weight]

Very blury image.

 

[JRRNeiklot]

Sorry, the best I can do lying on my back in the mud, in the rain with a cheap phone.

 

[highdesertranger]

"Sorry, the best I can do lying on my back in the mud, in the rain with a cheap phone."

wasn't the trailer on fire at the time and an angry bear was chewing on your foot?

sorry I couldn't resist. just funning you.

highdesertranger

 

[JRRNeiklot]

Not all at once...

 

[DLTooley]

Simplest solution is just to abandon the wire, and take your own redneck engineering to the next level. If needed.

 

[crofter]

Very blury image.

I can see the white wire real good. There's three of them and a purple wire nut. I have never seen purple wire nuts before, just red, yellow, grey, and green.

Green or no insulation is ground wire.
The other colors vary depending if 12 volt DC system or 120 volt AC system. 
Tell us more about why you are interested in that there wire?
-crofter

 

[maki2]

Here is the big issue you are facing with red neck wiring. If white is the only color of wire they had around they will use it for everything and not bother going to the store for different colors of wires.

But wire color is also not consistent between device manufacturing companies. That is the situation I am facing right now as I am doing all new wiring for my vintage travel trailer. I have devices plus various sockets/outlets. Some have white ground wires, some have black ground wires and some things have green ground wires.

You will need to put labels on all the wires once you sort them out so that you know from now on what they connect to. Get yourself a roll of white or yellow colored electrical tape and a black permanent fine point marker. Place a piece of tape around the wire leaving both ends of the tape extending out from the wire to create a little flag, tag to write on. Easy and cheap redneck wire ID labels for a redneck wiring job

 

[crofter]

Great advice, maki.
-crofter