Switch Style Battery Disconnect

It could very well be on a motorhome, in which case it could make a difference.
Barney

beemerphile1 wrote:
Whatta ya got? No profile and no signature, we don't know what you are putting this on.

If on a trailer it matters, anything else it doesn't.

Read this recent thread if you are putting it on a trailer rather than hashing the whole thing all over again;
http://www.rv.net/forum/index.cfm/fuseaction/thread/tid/27000134.cfm

Isn't this a rv forum, logical thinking would mean it is trailer related.

Whatta ya got? No profile and no signature, we don't know what you are putting this on.

If on a trailer it matters, anything else it doesn't.

Read this recent thread if you are putting it on a trailer rather than hashing the whole thing all over again;
http://www.rv.net/forum/index.cfm/fuseaction/thread/tid/27000134.cfm

The dealer installed mine on the negative battery terminal:

The switch will have a particular size clamp that clamps onto the battery post. It will be obvious if the switch doesn't want to fit well on either the neg or pos post. Of course like everything is life it can be forced to fit either.
Kinda like a good cross thread beats the heck out of a lockwasher every time.

If one installs manual switch on "+" battery post, then its emergency break-away switch won't work if the switch is accidentally left off. If one installs manual switch on "-" battery post, then its emergency break-away switch won't work if the switch is accidentally left off. This is very dangerous and illegal (re: no break-away switch while towing down the road).

Best to install manual switch on the "+" wire as shown below. The emergency break-away brakes wire can be connected to "+" side of the manual switch. Or, it can be connected to "+" battery post - using the small butterfly nut.

As seen in above diagram, above manual switch location allows active break-away emergency brakes - regardless if main chassis battery switch is ON or accidently left OFF (while towing).

There is NO electrical reason I've ever heard, either works fine. Just do whichever is simplier to do. For me the negative side was much easier to add a switch on.

NO - There is no good reason electrically... Only what works best for your particular system layout.

In my particular case I am using four batteries which have their NEGATIVE GROUND terminals all going to a separate FRAME GROUND connection. All of BLUE SEA sealed make before break high current switches are installed in the POSITIVE side of the batteries. In this layout the only single point place to totally DISCONNECT the 12VDC from the system would be in the POSITIVE side of things.

Consider my battery bank layout currently being used on my OFF-ROAD POPUP trailer.



My totally BATTERY DISCONNECT is the OFF POSITION of the first four position Blue Sea switch labeled BANK1 - BANK2.

just my thoughts
Roy Ken

If you disconnect the positive lead then you can cause a short with a tool or metal object. Removing the negative terminal and having it short normally only activates the battery circuit. That said, the positive side is just fine and very normal in rv's.

mdamerell wrote:
Normally they are installed in the red or positive(+) lead. Electrically there is probably a good reason for this which I suspect is to ensure the power is off.. Otherwise if you had a ground it might not properly kill the power.

Sure others can give a more precise reason.

That's what I was thinking just wanted to make sure there wasn't some crazy explanation to do the neg. terminal. Thanks