cut off switch question...

[doug hodder]

On my new build, I am planning on putting in a main cut off switch for the 12V source so it's not hot when I tow. In the past, on boats, I've used the "official" cut off switches, but they were running to the engine and would draw cranking amps for an engine. I don't want to drop the coin on one of those and was looking for a more economical solution. Here's my question: would a typical household switch work fine for the cut off between the battery and the fuse block that would only run lights, fans and aux 12V outlets? Are they designed to work with that voltage and amperage? The system will not be charged when driving if that matters. Sorry, maybe it's an easy one...but I'm an electrical dope, I did a search on cut off switches and came up with nearly 7500 matches....Doug

[madjack]

...this is what I used...hard to beat for 5bux http://search.harborfreight.com/cpisear ... &Submit=Go .......
madjack

[Kevin A]

Doug,

You could use one of these.

Or wire in some sort of relay to a keyed ignition switch or a plain toggle/rocker switch.

[doug hodder]

Thanks guys...the "official" marine ones that I've used in the past run like 30$...I'm looking for cheap this time around....Doug

[caseydog]

...this is what I used...hard to beat for 5bux http://search.harborfreight.com/cpisear ... &Submit=Go .......
madjack

That is what we use on track cars. That hole in the paddle is for a cable operated lever so that corner workers can cut the power without reaching into the cockpit or raising the hood if the driver is unable to cut power in a crash. Not really needed on a teardrop -- unless it is a South Central teardrop on a Saturday night.

[doug hodder]

So....do you all have on board extinguishing systems as well? Doug

[madjack]

mmm...fire good...mmm actually flame proof suits(goggles and gloves as well) are considered good for SCT gatherings...ask Mike Breaux...he forgot his at the LCG
madjack

[doug hodder]

Sounds like you all are pretty serious....do you also need a catch can man for the Coleman stove/lantern fuel ups?

[madjack]

Sounds like you all are pretty serious....do you also need a catch can man for the Coleman stove/lantern fuel ups?

errrrrrr, only when doing fill ups while they are still lit .............................

[Arne]

I'd go with a house switch.. they are good for at least 1725 watts..... assuming you also have a fuse at the battery.

I don't see a need for anything heavier, and it is not (or should not) be exposed to salt water, or any water for that matter... fresh water won't bother it, the volts are too low.

[Larwyn]

The electrical substations I used to work in all had DC emergency lighting (125 volts DC and maybe 100 to 200 watts of lighting). We used plain old everyday light switches with no problem but there was one occasion where someone had installed a "quiet switch" (one of those switches where you hear no click and it flips from on to off with almost no mechanical resistance. The DC lights turned on and worked fine, ONCE, when the switch was flipped to the off position it set up and arc inside the switch housing that would not break, had to turn off the supply at the DC breaker panel. So I would use a switch that makes good "snap" when switched off, DC needs to be "broken" much more quickly than AC to avoid arcing.

[satch]

To be safe, I'd go with a switch that's designed for dc. I heard somewhere that ac switches don't handle dc amps very well.

[Larwyn]

To be safe, I'd go with a switch that's designed for dc. I heard somewhere that ac switches don't handle dc amps very well.

You are right, either switch will handle the amps while on but a DC switch is designed to toggle off quickly usually by means of a spring, kind of like a mouse trap, so the contacts open at the same high speed regardless of how fast or slow you move the lever while the speed of the AC switch is controlled by how fast you move the lever.

[dovaka]

i have the same switch madjack does and it works great
the problem with using a household switch is that dc current arcs more then ac does and over time it will ruin the contact points in a normal light switch and if done under any kind of a load just accelerates the process and could actually weld it self together
the other switch is also a good reminder to take it out when your storing the tear or going to leave it for a long time

[planovet]

Thanks guys...the "official" marine ones that I've used in the past run like 30$...I'm looking for cheap this time around....Doug

Didn't you recently say:

I've found that you're better off to do it the way you want from the get go rather than to look back and say: Boy I wish I would have done it this way or that. At that point, all you've done is create more work for yourself and waste money if you want to change it.

Just use one similar to what MJ showed. It's $5 and you won't have to worry about it.