Question about charging Dual Battery system.
I've been reading up a lot on electronics, relays, diodes, types of switches, etc... I just installed an electric fan for my 258/4.0 head/ MPI engine on the outside of the radiator to assist the stock fan. I wired in a regular on/off switch and an adjustable temp. activated switch. I'd like the fan to stay on after I turn off the engine, but not be able to keep me from running my battery down. I was thinking about putting in a dual batery set up and how I would keep the fan from draining both batteries. I remember about CJDave's oil presure switch; I even printed out the whole thread on the dual battery setup so that I'd have it if I needed it in the future. I had thought that, instead of using an oil pressure switch to close the circuit between the batteries, why not set up a circuit of sorts to run off the ignition switch. When the igniniton is on the circuit is closed, when the ingnigion is off, switch is open. I was thinking to use a relay, but you'd have to use a pretty big relay for that. Is there any other way that anyone can think of to do this by the ignition instead of using an oil switch?[img]/wwwthreads_images/icons/tongue.gif[/img]
4.2 w/<font color=blue>(4.0 head & MPI)</font color=blue>
Process of a moonguy after beer
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