The regulator is what varies the field excitation, so I would say that if you open that circuit with the battery auxilliary field contact you should be fine.
Ie open circuit the field/regulator circuit
This is so that you do not damage the alternator when there is no load attached to it.
Is this what you are trying to achieve?
In order: Yes, I know. Yes, I know. Yes, I know. Yes, that's what I'm trying to achieve.
But with an internal regulator that field exitation wiring is all... well, internal. With one exception--see the URL I'm posting, below.
1. Most battery switches these days are make-before-break. You definitely want one of these if you're gonna switch between batteries while the engine is running. If you break the connection, you could blow the diodes in your alternator very quickly.
Yup. Thus the impetus to do this.
2. Yes, 200A should be plenty to start an Atomic 4.
3. You can trace the output wire from the alternator and see if it runs to an external regulator. If not (i.e., if it runs directly to the battery or a fuse) then the alternator has an internal regulator.
Ah, yes, if it's an external regulator, the main rectifier output will probably stop on its way to the batteries, as it were, for the voltage sense, right? Good catch. Hadn't thought of that.
I don't know the details of you specific alternator, but usually even alternators with an internal regulator have a field wire coming from the key switch or engine panel.
Wrong circuit, Steve. That circuit is only used to "prime the pump," as it were. It supplies field current until the alternator gets going, then the alternator supplies its own, whether an internal or external regulator.
Here's a good explanation of How Alter-nators Work
. (Sorry for munging the word, but Sailnet's "word-hijacking" stuff was screwing-up the URL.)
The output of the diode trio
is what one needs to interrupt with the field disconnect protection. On an internal regulator, that's not accessible, practically speaking.
Thanks for the feedback, guys