# briggs and stratton dual circuit alternator

Discussion in 'General Electronics Discussion' started by blownfuse, Jun 18, 2013.

1. ### blownfuse

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0
Jun 18, 2013
Hello everyone

I have a Briggs motor with what they call a dual circuit alternator on it. It has 2 windings both making AV voltage. One side has a diode making half wave unregulated DC voltage to charge the battery and the other is just to power lights. The only specs I can find are that the DC should be 3 amps and the AC is 14v. I know this is an unregulated system but the DC volts should be between 12.5v and 15v for battery charging so I'm guessing it's in that range.

Here is my problem. I want to run an electric PTO that requires a minimum of 4 amps DC that came off a later model motor that has bigger magnets on the flywheel with a different stator for a 9 amp regulated system.

So my question is, using the alternator and flywheel that I have is it possible to come up with a charging system that would power the PTO. Two thoughts I've had.

1)Replace the lights with LED and try to run them off the battery and then use a bridge rectifier for the AC side to power a second battery. If it's close I don't mind putting a trickle charger on the second battery when I'm done running the tractor as long as I can get a couple hours out of the battery before it wont run the PTO anymore.

2)Replace the single diode with a bridge rectifier. I'm getting beyond my knowledge here but if I did wouldn't I increase my output using a full wave instead of a half? I would need probably around 6 amps 14v to charge the battery and run the PTO and I would still have the AC side for the lights.

3)Somehow combine both AC lines from the alternator and make up an entirely new charging system.

Any help or ideas are appreciated. Thanks!

2. ### blownfuse

2
0
Jun 18, 2013
Am I correct in assuming if the DC side is outputting 13.5V with half wave rectification, than the AV output must be around 27.6V accounting for diode drop? How would I figure out how many amps on the AC side?

Last edited: Jun 18, 2013