Main 12V electrical disconnect switch

[NW Snowbirds]

While storing my new 31SL I turned off the wall mounted main electrical switch in the battery compartment thinking all of the 12v power was killed. While fixing another problem today I inadvertently pressed the water pump switch and was surprised to hear the pump turn on while the main switch was off. I have had several boats with odles of batteries and switching off the main disconnect killed all 12v power. But on further investigation I found that the hydraulic pump and slides all had power and were functioning as were the front cap hitch lights. About the only thing I found without power was the inside lighting and the automatic key fob door locking device. What the heck?

The positive cable from the batteries connects to a two pole connector. From there the power is routed to the main disconnect switch. But, there are two other red wires approx 12 gauge that also go somewhere. Both have internal circuit breakers in the lines and lead toward the hydraulic pump and elsewhere.

Any ideas what's up?

[Blenhardt]

All of the fifth wheels that I have owned (Four) leave power to the jacks and slides even when the 12 volt disconnect switch is off. Don't know about the water pump.

[NW Snowbirds]

No longer a problem. I rewired the 12v so that it first goes thru the disconnect switch. Works great. No problems when underway or camping. It's almost impossible to hitch up and tow away forgetting to power up because the main disconnect must be turned on to operate the hydraulic jacks to hitch up. Now I no longer must remove cables from batteries when in storage to isolate the batteries from the phantom draw that was drawing down the batteries. Had to purchase one 3 foot long 6 gauge cable with large eye connector on both ends (from auto parts store for US$7)to make the fix. Took about 15 minutes once I had the cable.

Terry

[JellyStonePark]

We too have been hunting for whatever it is that is drawing down our batteries while in storage. Can you send me a diagram of what you did on your coach, as I am running out of ways to keep our batteries from draining. If you like I will provide you with my personal email address so we can take this offline. Thanks

[piper guy]

Terry - x2. I did mine that way also. I also put in a second disconnect for battery 2 so that if I'm leaving the coach for a day or two and need a battery on I will still have a fresh one to bring on line when needed.

Later this summer when the GenSet gets installed, it will have its own starting battery

[spindrift]

Originally Posted by piper guy

Terry - x2. I did mine that way also. I also put in a second disconnect for battery 2 so that if I'm leaving the coach for a day or two and need a battery on I will still have a fresh one to bring on line when needed.

Later this summer when the GenSet gets installed, it will have its own starting battery

Vaughan...what's your plan for the battery's charging circuit?

[Rick and Mindy]

Headed to the Service Center to pick up my 31Sl. Will be there tomorrow. One of the items on my list was the battery disconnect. Service manager says when the disconnect is in the off position there should be no drain at all. I told him that I was having a problem with mine and several on the forum were having problems. He said he would take a closer look at mine. Hopefully they have re-wired to completely shut battery off. I will know real soon. Obviously someone at the factory doesn't know what he/she is doing.

[piper guy]

Spindrift ~ thinking of putting in a separate charging wire to the genset battery that bypasses the shutoff. That wire would have a diode in it to prevent backfeed and that way would only be supplied charging when the converter is on but the disconnect for the gen could remain in the off position to prevent draining that battery.
I'm planning on using a small tractor battery for the genset as it's engine isn't that big to crank.

I think the converter should handle it with no problem.

[spindrift]

Please elaborate on the "disconnect for the gen could remain in the off position...".

Thanks.

[piper guy]

More I think about it, a disconnect isn't really needed for the GenSet as that battery won't be connected to the battery bank. It's only purpose will be to start the generator. Only need to run a charging wire over to the battery and put a diode in that wire. Diamond acts like a gate, electricity will only flow one way. That way if you wire it correctly, the current from the converter will come into the battery to charge it but there will not be any back flow into the coach system.

As long as I'm thinking this correctly , want to run it past my friend who does 12volt installs of Police equipment for a living to make sure I'm right.

[spindrift]

I believe you're correct. I was wondering why you were installing a second disconnect. I don't see a need. Please post back what your buddy says. Thanks.