Testing for Charge at Cutout

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Testing for Charge at Cutout

Postby Stanton » Fri May 08, 2015 9:26 am

This is a 6V generator with cutout.

By removing the wire at the BAT cutout and putting your multimeter leads on it and ground, shouldn't you get a reading of 7V+ while the engine is running?
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Jim Becker
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Re: Testing for Charge at Cutout

Postby Jim Becker » Fri May 08, 2015 10:08 am

I wouldn't recommend that particular test. It might crank out 30 or 40 volts and could burn out the generator.

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Gerry Powell
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Re: Testing for Charge at Cutout

Postby Gerry Powell » Fri May 08, 2015 10:39 am

that is what you should read running with the battery connected. Measure the voltage with the tractor not running, when running it will increase if charging. With the battery disconnected, no charging current can be delivered to the battery and the operation of the cutout can't be determined.

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John *.?-!.* cub owner
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Re: Testing for Charge at Cutout

Postby John *.?-!.* cub owner » Fri May 08, 2015 1:04 pm

I have done that test just as an experiment and with the light switch set on LO charge, and engine at about 1/3 speed I got about 36 volts, though I only ran it very briefly that way since I did not want to risk damaging generator. Most digital meters will give very erratic readings connected directly to the generator though, you need an analog (pointer type) meter. As Jim stated, it can damage your generator. If you have the same voltage at both the battery and generator terminals when running, your generator is charging (though you will not know how much), since it is voltage from the generator that pulls the cutout relay closed. That is of course, unless the relay is stuck, in which case you will also have voltage at generator when NOT running.
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