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Lexhandu
06-11-2017, 05:44 PM
We purchased a used 2015 Passport 2250 RB with dead battery. We have purchased a new battery but cannot find anything to tell us the color coding on the travel trailer wiring. We didn't take good notes 😢Is white positive and black negative or visa versa? We are going to install a disconnect switch. This goes on the negative? Thanks from a newbie :confused:

Hatch8339
06-11-2017, 05:48 PM
Hi there welcome to the forum on keystone products the black is positive am
No white is negative and your disconnect go on the positive side hope this helps you out

Hatch8339
06-11-2017, 05:50 PM
I meant to say and the white not am no auto correct lol

ctbruce
06-11-2017, 05:51 PM
Black is positive and white is negative.
Welcome to the forum from Kansas City, MO!

Sent from my SAMSUNG-SM-N910A using Tapatalk

fourfourto
06-11-2017, 05:54 PM
I've always used the negative for the disconnect switch.

:facepalm:

Lexhandu
06-11-2017, 06:32 PM
Thanks! My autocorrect sometimes uses words that I shouldn't ����

chuckster57
06-11-2017, 06:50 PM
Every factory installed battery cut off is on the Positive side.

If you cruise the www you will find adamant arguments on both sides. Which is right? Let's not start that here, let's just agree that a cut off is better than nothing if your going to leave the unit unplugged and battery installed.

busterbrown
06-11-2017, 07:59 PM
Most automotive repair manuals I've read illustrate disconnecting the negative side of the battery prior to electrical work. Does it tend to arch less than a positive post disconnection? Haven't really noticed in 25 years of shade tree mechanic work.

JRTJH
06-12-2017, 07:08 AM
If you've ever disconnected the positive terminal on a car/truck battery and had the wrench also touch ground (vehicle chassis) you know the sparks and heat that are produced. I've seen wrenches "welded" between the battery terminal and the chassis, I've seen wedding rings become "circumferential vaproizers" of human fingers and I've treated the wounds from such accidents. I personally won't put a wrench on a positive terminal (of a negative ground system) without first removing the negative terminal. Whether it's a car, a truck or a RV, if you ever ground out the positive terminal it becomes "a big battery issue" with no time to "back up and change things"....

NHRA and marine applications dictate that battery disconnects be installed on the positive terminal of the battery. Some (not all) battery switch installation instructions call for installation on the negative side, others call for the positive side.

Now, from an electrical connection perspective, it's "mandatory" to install it on the positive side IF you want some components powered and others not powered when the switch is off. (think RV wiring and phantom loads from the LP detector, CO detector and radio faceplate). Actually, the switch only turns off "part of the positive pathway" in the battery circuit. If it were installed on the negative side, it would either have to turn off ALL battery power (including phantom loads) or the power would use the "alternate ground" and bypass the cutoff switch (which is the reason the positive side is used in NHRA and marine applications).

As Chuckster said, in OEM RV applications, the switch is installed on the positive side, to allow for safety devices to remain powered. If you do choose to use the positive side, please make sure you remove the negative terminal EVERY time you are working with tools that will contact the switch or the positive battery terminal. One time of grounding a wrench at the battery or at the battery cutoff switch terminals and you'll know the danger involved in trying to weld your finger to the RV.

dcg9381
06-12-2017, 10:04 AM
I'd NEVER depend on "color coding" out of Keystone. It should be easy enough to trace the ground, which will touch the trailer frame... And yea, I've arc welded a few wrenches in my case when I didn't disconnect negative first.

Stickman
06-12-2017, 02:36 PM
Regardless of whether an electrical system is negative or positive ground, always, ALWAYS disconnect the ground side of the battery before attempting work on ANYTHING with a direct, unprotected path to the "hot" terminal.
Knew a mechanic who was working under the dash of a tractor, and had the 4 ga. hot accessory feed disconnected from it's firewall terminal. The cable end came into contact with his wedding ring, which was also in contact with the steel support fixture for the steering column. In an instant he had four 1100 amp batteries juicing thru the perfect conductor of that 24kt ring. He was stuck there until the ring burned down to the bone and turned molten enough to break the connection. He learned his lesson the hard way by means of losing that digit.:facepalm:

Desert185
06-12-2017, 03:43 PM
I never, ever wear a ring when working on a vehicle. The working watch is plastic.