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Old 11-26-2007, 10:22 AM   #192 (permalink)
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12-09-2006, 11:39 Pm

SW makes another important observation:

Originally Posted by SW
I read that it's actually possible to overspeed series wound motors if you run them w/o a load even though speed limits current flow. I would think the comm timing could have a huge effect on how the field and armature fluxes interact. I have no personal experience though.
You're right about overspeeding a series motor with no load. At least I've read the same thing.

Ours stabilized at 2275 RPM on 12v (no load, "stock" rotation direction). I'm sure it would have been a different story had we spun it on its rated 48v - we would have had a problem.

On the EV list: Jim Husted, a well regarded motor technician, asked me for pics of the motor. I'm happy he replied - I'm sure he'll be able to further my education.
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