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sdgrand
03-03-2010, 03:55 PM
I have an old motor which I'm thinking of using as a jackshaft for a speed reducer. Do I need to do anything (other than unplug it) to avoid creating electrical or other problems? Thanks in advance for your thoughts. Shel

digr
03-03-2010, 06:41 PM
I believe it could turn into a generator but as long as there is no wires hanging out you should be OK. I take it it is a double shaft motor?

pigpen60
03-03-2010, 07:03 PM
if its an permanant magnet dc motor it will produce current, if so pull brushes if its an ac it shouldnt do anything. hmm wild thought if its an pm dc motor put a resistor and a proper sized switch and you have a braking system! pigpen

ADGO_Racing
03-03-2010, 07:45 PM
An AC motor WILL also produce current....All motors will if driven. However, unlike a DC motor it won't produce as much power, but still enough to get your attention.

pigpen60
03-03-2010, 11:34 PM
whats exciting it? residual magnatism? pigpen

rdfeil
03-03-2010, 11:41 PM
Adgo,

Incorrect, an AC motor will NOT generate unless excited as pigpen implies. If there is a small residual magnetic field there may be some generation, but it will be very small. Now a PM DC motor.... watch out :eek:

Robin

Bguns
03-04-2010, 02:48 AM
Incorrect Some AC motor designs can generate power with no excitation.

A couple capacitors need to be added...

Residual magnitisim will work...
This example will not power another motor but works well with resistive loads:

http://www.qsl.net/ns8o/Induction_Generator.html

rdfeil
03-04-2010, 10:37 PM
Adgo, Bguns...

I stand corrected...

Robin

doctor demo
03-04-2010, 10:49 PM
Adgo, Bguns...

I stand corrected...

Robin
Really? I sit when I type.:D

Steve