Community Forums

Kdjay · 12-15-2014, 05:29 AM

My DH removed the battery from our camper (215 wsk Fun Finder) and didn't mark the positive or negative cable. One is green and one is red. Which would be the positive cable? He emailed the manufacturer who said they don't use red and green wires. Hmm, bought it new from a dealer so it came that way.

wb7auk · 12-15-2014, 06:46 AM

Red is normally positive
If that is the only 2 cables I would go with normal.

IC2 · 12-15-2014, 06:49 AM

TT manufacturers don't usually supply a battery, leaving it up to the selling dealer to install (he can put several different sizes in the box and at different costs to you or him). The manufacturer may not have shipped the cables, also leaving it up to the seller. With what you are saying, I would take a low cost battery powered continuity tester or voltmeter with an ohm setting (Home Depot/Lowe's/Harbor Freight/ Radio Shack) and figure it out yourself. Making sure the trailer is not plugged in to 110V house current, take one of those cables, hook on the tester and with the other end, touch some bare steel (frame, preferably). You may have to scrape a little paint off to find bare steel. The cable that turns on the light or moves the needle way over is the ground (it will probably be the green one) with the other of course, being the battery plus - but then who knows what lurks in the minds of some service folks

wb7auk · 12-15-2014, 06:49 AM

Green is used as ground in AC systems not normally seen in DC systems.

"007" · 12-15-2014, 07:07 AM

Chase the other end of green cable if it goes to TT frame its your negative cable " Ground"
As said red would be your positive.
TECH TIP's

Kdjay · 12-15-2014, 07:28 AM

Thank you

wa8yxm · 12-15-2014, 03:08 PM

Red is NORMALLY positive however .... This is not etched in anything as a standard, I have seen red as the negative cable and bought a new alternator due to a tow operator making an Assumption, he forgot how to remember to spell assume you see (-u-).

Take a volt meter (DC 20 volt range) hook to the cables, plug in and see which way it shows. IF you hook red to red and black to green and it says something like 13.6 RED is positive, put a black something on the green wire

If it says -13.something Well then Red is negative.

BFlinn181 · 12-15-2014, 04:14 PM

ICU and 007 gave good, simple ways to determine polarity of the cables. In addition, if your battery cables are the type that clamp on the round lead posts on the top of the battery, the larger in diameter post is always positive. Unless the cable clamps have been excessively loosened, that also should help indicate (+) (-). If the cables are side post terminals, all bets are off, Automotive cables aren't differentiated. Marine side cable posts use different size bolts.

Kdjay · 12-17-2014, 04:53 PM

We found the answer. White is ground, red and green are both positive. The dealer changes the wiring so feedback at the campground would not hurt the inverter. Note: I my earlier posts I neglected to mention the white wire. My DH never said there was a white one!