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Alternator RPM

Posted by poohbear2767 (My Page) on
Sun, Sep 3, 06 at 16:36

What RPM should an alternator spin at
to put out max power.

I'm am wanting to build a portable power supply.
Let an alternator charge a battery, run 12vdc stuff off that,
or hook up an inverter and run 110vac stuff off that.
I tried running my inverter off the tractor battery,
but I had to run the tractor at full throttle to keep up.
Otherwise I kept getting a low voltage warning beep.
So I want to run an alternator off the PTO at idle speed.
and use a speed increaser to increase the RPM.
PTO speed at idle is about 200RPM.
What should the alternator RPM be.

I already have a water pump I run at 2800 RPM.
I use a 14:1 speed increaser.
If 2800RPM is about right I will run it off that shaft.
Or use pulleys to change the RPM.


Pooh Bear

Follow-Up Postings:

RE: Alternator RPM

Pooh Bear, read this article and I think you will be all set.


RE: Alternator RPM

Great article thanks.

So I guess about 5000 RPM. I need a 2:1 pulley setup for it.

Alternator pulleys are what, 3 inches,
so I need a 6 inch pulley on the 2800 RPM shaft.
I'll measure this all to make sure.

Thanks a lot.

Pooh Bear

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