Anyone using one of these to keep at least one battery alive in a drain situation?

Use one on my boat. Works great.

I was interested in a slightly different application. Using it to isolate only one of the batteries, in a discharge situation

I was interested in a slightly different application. Using it to isolate only one of the batteries, in a discharge situation

That's what it does .....I have the isolator installed and wired from the alternator. It charges both batteries when the boat is running but "isolates" my auxillary battery so that only it drains when things are being used (engine off) so that the main starter battery stays up. It's all automatic - no cut-off swithes etc.... :confused:

Are you looking for a discharge only isolator? Use the current OEM charging system to charge both battery's but only allow discharge from one battery for an auxillary item?

I have one similar to THIS (http://www.jcwhitney.com/autoparts/ProductDisplay/s-10101/p-1028/c-10101)

I think i remember you describing this on another thread. So you have a 2 battery isolator?

I am just not sure which battery to "isolate" on the GM

It was'nt me that posted info previously but I think I know where your are going with this.......the type of isolator I have is for IIRC an alternator that has an internal regulator. The batteries have to be wired seperately, not parallel as our trucks are. Might be a tricky set-up to do on our trucks if only using the original 2 battery system unless your planning on a third battery.

OK, parallel, meaning 12 volt system, not unlike an off-the-grid battery bank charged by solar or wind. I guess that would be a special application isolator.

Painless Wiring has a new model out with a dash switch and mi-spec, waterproof wiring. Dash switch lets you select one or both batteries. Good for winch owners.

OK, parallel, meaning 12 volt system, not unlike an off-the-grid battery bank charged by solar or wind. I guess that would be a special application isolator.

OK....I'm trying to stay with you on this:) My use of the term parallel was not meant to apply to a 12V system - only that the batteries must be wired seperately for their draw so that one does not drain the other. If you were using two seperate sources to charge each battery (ie charge one off an alternator and one off of solar power) then all you would need is to isolate the draw or wire each thing you want to run off of each battery seperately to each individual battery so that one battery does not drain the other as in the diagram.

I understood, your post was helful. Parallel=12V, series=24. I am trying to determine if it is possible to isolate a battery we want to keep parallel, for good reasons.

TxDoc, could that also be used as a security device, dead man type?