gen test

Electrical issues
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64 pan
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gen test


Post by 64 pan » Mon Jul 13, 2009 5:48 pm

how do i hook hp to run gen as a motor

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Re: gen test


Post by steve_wood » Mon Jul 13, 2009 7:41 pm

This is something that Joh HD taught me. He deserves the credit. Note that it's not foolproof. I had trouble with my generator. I tried the motor test and it spun, but it turned out to have a defective armature. You'll need to take it to a shop with a growler for a definitive answer.

"here is the motor trick:

on your non conductive work bench place your generator and a fully charged battery.

connect a cable from the frame of the generator to the neg terminal on the battery.

connect a cable to the positive terminal on the battery. then connect the other end to the A terminal on the generator.

now take a jumper from the F terminal and ground it to the frame of the generator. this is your switchable lead.

it should start spinning as a motor.

couple words of caution, make and break your connections at the generator to prevent sparks near the battery! also, since there is an unkown problem with this generator a 30 amp fuse in the positive lead may be a good idea!

once it starts running as a motor you can experiment by wiggling the field wires for any intermittants, also you can try pushing on the brushes with something like a toothpick to see if it speeds up or not. (this check is for weak brush springs) you can also try cleaning the comutator as it is spinning with sandpaper and see if the rpms increase.

the faster it spins the better it will in turn generate!

the nice thing about doing this is if something screws up it will stop turning and you will not waste any time reinstalling a non functional unit.

as mike pointed out this test is not fool proof, the only thing this test cannot detect is a flying short in the armature. basically it will not spin fast enough to dislodge a loose wire that opens or shorts at engine rpm."
Last edited by steve_wood on Mon Jul 13, 2009 10:03 pm, edited 1 time in total.

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Re: gen test


Post by PanPal » Mon Jul 13, 2009 9:13 pm

I had trouble with my generator. I tired the motor test and it spun, but it turned out to have a defective armature
Mine would not spin, It ended up being fine, my problem was the regulator.

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