New owner! Anyone know what this wire is?

[r1666a]

Hi Everyone. Glad to be on this forum. We bought a new Prism DS2250 and had a few build QC issues so whilst I was looking around I found this large guage wire very close to the ground bus bar.

It is located under the cooker/fridge area next to the water heater. All the wires are white and seem to be negative 12V so Im thinking that this fat wire also needs to be connected to the ground bus bar below it.

Any ideas welcome!


The base of the image is to the right so if you tilt your head left you will see how it is in the RV.

[clr]

Well it looks to be a ground bar or neutral bar. Because all of the white wires are connected in common there. But my question is why is the large white cable not connected to the end of the bar under the large connector that is vacant.

[r1666a]

Originally Posted by clr

Well it looks to be a ground bar or neutral bar. Because all of the white wires are connected in common there. But my question is why is the large white cable not connected to the end of the bar under the large connector that is vacant.

That large one at the end is actually the screw that holds the bus bar. However there are plenty spare holes.

I just wanted to understand if the loose wire can be connected to that bus bar. It would make the most logical sense but Im not 100% and didnt want to break my new rig!

And sorry, thats how I found it hence the question

[Macrosill]

It looks like it belongs in the second hole from the left. The first is the mounting screw and the second appears empty with the green screw backed almost all the way out, which would seem right for the larger size conductor.


The above is just a guess based on what I see in the picture.

[Scrapper]

It looks like the large gauge wire may be the main ground for the 12vdc system. Either going back to the battery or to the frame. Does the wire reach the buss without any problem? Does any of your 12vdc appliances work? Have you tested the wire with a volt meter? I doubt it is a 120volt AC neutral wire, because it's stranded, I don't think there will be any harm if you connected it.

RV manufacturers do not follow the normal red=positive, black=negative wiring schemes common in the automotive industry.

[r1666a]

Perfect thank you guys. I shall do that. Four brains are better than one!

[Scrapper]

Come to think of it I've never seen a negative buss for 12vdc. The negative wires are normally ran to the closest part of the frame.

[DougW]

Have you tried to follow that wire to see where the other end goes? If it is possible to do so it might tell you just what it is for.

[dmctlc]

If I'm not mistaken you said "new" in the sense you just bought it brand new. If you're are close to the dealership you bought it from I'd call them, tell them you'd like to swing by with it for a quick fix or maybe a tech could take a minute to tell you if it's safe to connect. Chances are it's a ground, but do you want to find out the hard way it isn't? Like SCRAPPER stated they don't follow the normal process for color coding wiring, in fact my experience has taught me they don't even wire things up in ways that make sense some times. If you're too far from the dealer, speak to the Service Manager and see if you can send him a few pictures and maybe he, or a tech can tell you without leaving the driveway. Better safe than sorry, especially where it could cause more electrical issues if you're wrong and it fries something when you connect it. Then it could be a costly mistake to you because it will void the warranty. IMHO...

[bubbles]

Originally Posted by Scrapper

Come to think of it I've never seen a negative buss for 12vdc. The negative wires are normally ran to the closest part of the frame.

Yes, but there doesn't appear to be any frame work in the area and therefore a ground bus bar would be the ticket. Just guessing what it is of course. And if it is a ground bus not insulating (isolating) it would not be a problem.

[bob5560g]

You could also look at the exposed copper end it and see if it was pinched by the screw, but later slipped out because the screw wasn't tight enough. Of course if was never installed or they forgot to tighten...

Also, you could check continuity from it to the 12V bus bar shown.

[TitanMike]

Originally Posted by Scrapper

Come to think of it I've never seen a negative buss for 12vdc. The negative wires are normally ran to the closest part of the frame.

In my TT there is a bus bar for all 12 v negative connections right behind the Power Center/Converter. One negative lead from Fuse board goes to frame and a second negative lead from fuse board goes to negative bus. Also one negative wire from actual converter to fuse board.(as well as positive wire of course).

Only one connection to frame for 12 volt items except slide and tongue jack which have direct negative connections.

That's just my TT but I'll wager it's not the only one.

[vasnipe]

When I replaced my converter this Spring the Negative / White wire from the converter connects to the terminal strip as shown. While you are in there check the rest of the wire connections and if needed tighten them down. I found only 1 that gave a slight "creak" when I turned it, the rest were OK.


Hope this helps.


Chris in Virginia

[steven skare]

Normally the white is a neutral, and green our copper is ground. I would go back to the dealer.

[phipps33]

Originally Posted by steven skare

Normally the white is a neutral, and green our copper is ground. I would go back to the dealer.

In an 120V AC situation, yes, but not necessarily in 12V DC.

[TowPro]

Problem is its too large for that little hole it came out of.
I would use one of these, than that large wire will fit and it uses 2 of the smaller holes in your bar.
Home Depot has them under 10 bucks.