battery disconect switch

[harleyrider]

Which side pf the post do these install?Positive or negitive.Electricy isn`t my strong suit.Thanks for your help.

[foggyb]

Hi Harleyrider All boats use the positive side which I did in our monty. Dan

[padredw]

Just to second the reply of foggyb: it is the positive side. Note red wires on left of photo:

[harleyrider]

Thanks for your quick replys.It will be nice just fliping a switch instead of taking off the cables to disconnect the batteries.As it turns out my selling dealer put the cheapest battery he could find when I bought the Montana.Typical for this guy.It wasn`t even a deep cycle battery.I guess he just didn`t want to spend the extra 30 bucks to give me a decent battery.Thank God i`am threw with that dealership.

[tollmann]

We switched the ground side. I was told to do it this way with the knife switch that we used. I did not want a hot bare uninsulated knife switch out in the open in the front storage area of my rig. If something fell off the shelf and shorted between the switch and ground it could cause major problems.

[Bill and Ann]

I installed a switch similar to the one on our sailboat. It has a stop for batt. 1, batt. 2, both and off. I usually keep 2 batt. on board.

[mazeeff]

quote:Originally posted by padredw

Just to second the reply of foggyb: it is the positive side. Note red wires on left of photo:

I would switch the ground side. The problem with switching the postive side is safety. In the picture above, you MUST have a fuse between the positive battery terminal and the switch. I see a open 12 volt postive terminal on the back of the switch, which is very dangerous. If you make contact between that terminal and the metal bracket behind it, you could have an explosion. Switching the ground side is a lot safer. Just my opionion of course!

[Countryfolks]

Switching both lines is the safest. The problem I see with a switch in the ground side is you have power available in all of the circuts, just waiting for a ground. That would usually be me!! The usual instructions given when working on a vehicle, for example, is remove the positive cable from the battery. The photo is actually safer since it localizes any danger such as the exposed terminal. Any exposed terminals on the switch should be protected.

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[mazeeff]

quote:Originally posted by Countryfolks

The problem I see with a switch in the ground side is you have power available in all of the circuts, just waiting for a ground.

Let me clear this up. Switching the ground does not provide power to circuits in the trailer. The power is coming from the battery, so the only way that the circuit can be completed, is by completing the ground through the battery switch! Grounding the trailer through any means other than the battery will not power the circuit.

[padredw]

Just a quick note to say that before I inatalled this switch I inquired on this forum as to which "side" it should be connected to. At that time (I can't find the thread now) I was clearly advised to put it on the positive side. I faintly remember that it had something to do with the fact that cutting off on the ground side would still permit some 'leakage'. I am not sure about that, but this discussion has caused me to remember why I installed as I did. I'm still willing to learn.

[mazeeff]

quote:Originally posted by padredw

Just a quick note to say that before I inatalled this switch I inquired on this forum as to which "side" it should be connected to. At that time (I can't find the thread now) I was clearly advised to put it on the positive side. I faintly remember that it had something to do with the fact that cutting off on the ground side would still permit some 'leakage'. I am not sure about that, but this discussion has caused me to remember why I installed as I did. I'm still willing to learn.

Switching the positive is a common suggestion, but can be unsafe, as I indicated prior. If you leave yours this way, please be VERY careful. Switching the ground can not result in any "leakage" problem, as long as you position the switch on a short cable to the battery. The "leakage" myth comes from house wiring background, where the house is earth grounded. In an RV the negative battery terminal is only connected to the battery at the source. Once it is switched, there is no path for the current to flow. If you switch the ground, the terminals on the switch will be ground, when the switch is on, and pose no hazard. I work in the Telecom industry and work on batteries every day. They hold a lot of energy, and a short from that battery switch you installed to ground will result in a tremendous surge of current that will result in one of two results. Either the metal (like a screw driver) will arc and melt, or the battery will quickly overheat, and can explode. If the battery explodes, you could be covered in battery acid. It would be easy in your case to simply move the switch to the ground side of the battery. Buy a short black cable to keep the color code correct.

[padredw]

Thanks, and I am still learning. One note however: the terminals behind the switch are covered, doubly. That is silver tape which is visible. I just checked to be sure. An insulator was provided with the switch, and the tape is to be sure everything stays in place.

[mazeeff]

quote:Originally posted by padredw

Thanks, and I am still learning. One note however: the terminals behind the switch are covered, doubly. That is silver tape which is visible. I just checked to be sure. An insulator was provided with the switch, and the tape is to be sure everything stays in place.

OK. My mistake. It looked like exposed metal.

[Thunderman]

Got to go with the ground side.

[tollmann]

When you work on a vehicle the ground cable is always the first removed. Less chance of sparks when working on the positive side.

[Countryfolks]

Folks, I stand corrected, Thanks.

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