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How to wire a modified series wound motor

832 Views 2 Replies 2 Participants Last post by  SeattleTrainGuy
Hello All, old guy here, but new to the forum. Recently I sourced a couple of freebie 7” forklift traction motors to convert an old 1/4 scale ICE miniature locomotive to electric drive. I got one motor running on the bench, but the second just buzzes a bit and let’s out the blue smoke. This one has some odd modifications, so I can’t figure out if it’s a lost cause or can be wired to run.

Thought I would ask here for some suggestions on how to make this functional. The brass straps apparently were added as a mod, to connect the brushes.

Any suggestions how to wire this up? I plan on running it with 48 volts...

Thanks much,
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Ok, so I dug a little deeper and solved the problem. The copper straps provide electrical connectivity to both sets of brushs. When I stripped down and re assembled the motor to inspect last fall, I did not properly isolate/insulate one of the mounting bolts that holds one strap to the frame. Hence the bolt was shorting the strap to the frame- causing the pretty blue smoke to waif up off the stud.

Used a small rubber washer to insulate the shaft of the bolt where it go’s through the strap into the frame, and wall-la, no more mister sparky. Motor runs like a top.
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