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Yankee802
05-10-2011, 04:42 AM
I've searched high and low and can't seem to find an answer, so I'll ask. :)

Does anyone know what the output of an (my) alternator on a 1984 Prevost is? I checked the owner's manual, nothing there. I'm pretty sure my chassis is 24v, and I believe my house is as well. I looked in the engine bay and couldn't see the alternator, or at least if I did, didn't recognize it. I'd like to know volts, amps, etc...

And while I'm asking questions, here is one about my generator. It is connected to my house bank for starting power. While running, is it also charging that bank, in addition to supplying power to the battery charger? Thereby supplying dual sources of charge?

Jon Wehrenberg
05-10-2011, 08:06 AM
Only you can answer those questions. The reason I say that is because of the wide range of variations due to converters doing things their own way and due to Prevost making changes over the years.

Get a multi-tester and check the voltages of various house DC powered components. Look at the data plates on your inverters or converters. All of these things will help answer your questions.

With the multi-tester read the chassis batteries' voltage with the engine off and the generator off. Then re-read the voltages with the generator running. If it goes up you know the generator is charging the chassis batteries. I doubt it because it is likely if it is charging them so is the shore power and if that is happening it is likely you end up ruining them quickly. That's not to say you do not have a charger. It might not be turned on.

The reason you cannot see the alternator is it is a gear driven 50DN probably 270 amps, 24 volts hanging on the back of the engine gear case. You can see it from below over the bell housing.

I suspect you have an isolator if you have only one alternator and it picks up 12 volts for your house from the 12 volt circuit on the chassis batteries. The equalizer keeps everything charged when the engine is running, and you have a converter or inverter/charger maintaining the house batteries when on shore or generator power. My guess is you have a 12 volt house but that is up to you to confirm in the absence of documentation.