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Steve Campbell
09-30-2011, 10:16 PM
Hi all. Been a while since I've posted much. Work has been getting in the way.
I have one of the new Delta 46-460. When I have it plugged in or unplugged when I turn the hand wheel one direction it turns harder than when I turn it the other way. When I flip the switch to reverse it now turns more easily the other direction. At first I just thought it was something in the electronics but it still does it when unplugged. I have tried a few in showrooms and they all do the same thing so I don't thinks it's a problem. It just has me stumped.
I have had this lathe for at least a year now and really love it. Just have that one question.
Thanks in advance Steve

Donny Lawson
10-01-2011, 8:16 AM
That's an easy one. When you have the switch turned so it goes foward the motor is basically geared for that direction and when hand turned in the opposite direction its like having the brake on. It does the same when in reverse and then try to hand turn it in the foward motion. It's nothing to worry about. It's how they are built. Mine is the same.

Jon McElwain
10-01-2011, 4:23 PM
Even unplugged, the motor has magnets in it that provide some resistance.

James Combs
10-01-2011, 6:21 PM
Even unplugged, the motor has magnets in it that provide some resistance.

What Jon said. It occurs because there is a breaking resister in the system which gives a path for the breaking current. The breaking current is created the instant the power switch is turned off (or you spin it by hand) by the armature windings cutting through the permanent magnet's magnetic field. The induced current is in the opposite direction of the normal power applied to run the motor so it is trying to make the motor run(brake) in the opposite direction. It doesn't matter whether the FR switch is in F or R the effect is the same. Hope this helps.

Steve Campbell
10-01-2011, 11:50 PM
Thanks a lot guys. I knew it was nothing to be worried about. I was just wondering. I know that none of my other motors does that. Now I know.
Thanks again. Steve