Battery Disconnect switch

[sgm26]

I am looking to install a battery disconnect switch to reduce electrolytic corrosion.

The problem that I have run into is that the standard disconnect switches are not intended to be installed in the starting circuit (not enough amps). If I leave the main lead to the starter connected then I am not really doing what I want to do.

I have found a knife switch and another similar switch that is attached directly to the battery, interrupting all of the power. However these switches are intended to be connected to the negative terminal (terminals are often different sizes). From the little I know about electrolytic corrosion, it seems that the switch should be attached at the positive lead. I have a way to keep the bilge pump connected.
My problem is finding a switch that will work

 

[achris]

Re: Battery Disconnect switch

Standard 'Cole-Hersy' type switch is good for about 300 amp continuous and over 600 amps peak... Unless you're cranking a SERIOUSLY big diesel, then the standard switch is more than man enough for the job you need it for.

I have installed many and never had a problem....

Chris.....

 

[seabob4]

Re: Battery Disconnect switch

Ummm, battery switches are installed by the thousands every day that cut out the starting circuit of motors. The positive lead off the batt goes to the "common" post on the battery switch, which is not energized with the switch in the off position.

You'll be fine...

 

[sgm26]

Re: Battery Disconnect switch

I probably over-thought it but the standard rotary switches require two new heavy duty cables, mounting and some re-wiring.

I found a Wirthco switch at Harbor Freight that simply attached between the Battery and battery cable. The neat thing is that there is a hole cross-ways through the lug where the battery cable attaches. While there were no instructions, I figured that I could simply put a bolt through this hole and attach the battery cable this way, when the battery cable was a bit too large. There is a large Knob that you unscrew to disconnect the battery.

Took about 15 minutes to install and cost $5.00, all in.

 

[bruceb58]

Re: Battery Disconnect switch

If this is the switch you bought I wouldn't use it on anything bigger than a 4 cylinder motor or an outboard...maybe. Also, not sure if it produces a spark when you open/close it.

http://www.harborfreight.com/battery-disconnect-switch-97853.html