# Motor connection question



## major (Apr 4, 2008)

NCMau said:


> I have a 120VDC, 9A motor, brush type. treadmill duty. Four wires coming out. The two larger gauge wire pair measure 3 ohms. The smaller gauge pair measure 250 ohms.
> I think the larger gauge is the DC input but I am not sure about the smaller gauge. Maybe the exciter?


Hi NC,

I think these motors are PM. No exciter. Small gauge wires are probably a thermal sensor. I suggest you start using the larger gauge wires at a lower voltage, like 12. It should run a about 1/10th speed. It will spark if you just touch the wire to the terminal of a battery. If you touch it and the motor does not spin, back off and let us know. This should be a safe way. 12 volts will likely not hurt anything.

Regards,

major


----------



## bblocher (Jul 30, 2008)

Any chance the two smaller wires are rotational sensors for safety purposes or possibly just to guarantee consistent speeds on the treadmill?


----------



## tj4fa (May 25, 2008)

I just hooked a 12V battery up to a treadmill motor I have and spun it up.

If your motor is like the one below, the red and black wires are the + and - that will run the motor.

The two blue ones are for the internal thermal switch as the case data plate indicates.


----------



## NCMau (Jan 27, 2009)

Thanks everybody. The motor does spun with 12V applied. Later I will jury-rig a bridge rectifier and apply the full voltage. Exactly what do I hookup to this thermal switch wire if I do want to use it? The plate does not indicate anything about thermal connection.


----------

