Fox T-Bird/Cougar Forums

General => Lounge => Topic started by: mattg on January 03, 2012, 02:08:47 PM

Title: help with DC electric motor (not in Cougar)
Post by: mattg on January 03, 2012, 02:08:47 PM
Hi-  I purchased this DC electric automotive fan motor to use for a display turntable.  I also got a PWM speed controller for it.

http://www.surpluscenter.com/item.asp?item=10-PM508&catname=electric

Whenever I bought an electirc motor in the past it had two leads.  This one has a just a little silver pin sticking out of it.    I'm pretty sure the silver pin should go to the positive lead on my 12v DC power supply,  and the negative lead from my power supply should attach to the motor's metal casing.    any ideas?    Thanks!
Title: help with DC electric motor (not in Cougar)
Post by: mattg on January 03, 2012, 03:42:49 PM
see pic of connector
Title: help with DC electric motor (not in Cougar)
Post by: Haystack on January 03, 2012, 06:14:53 PM
Well, to use a brushless motor with a pulse width modulation speed control, you would need at minimum 3 wires. All 3 should be powered and pulsed sperately. The way a pwm works is by automatically controling which part of the motor has power to keep it moving in the right direction, and speed. You have either the wrong motor, speed control, or wires going to the motor.
Title: help with DC electric motor (not in Cougar)
Post by: mattg on January 04, 2012, 09:01:19 AM
this one doesn't have dual windings.  just a single speed 2000 rpm motor.    The PWM controllers I've seen (not industrial but  more hobby / robotics oriented)  require two leads for power input,  12 volts in this case,  and have two leads for output.  the speed is controlled with a dial from 0 to 100%.
Title: help with DC electric motor (not in Cougar)
Post by: mattg on January 04, 2012, 10:11:43 AM
PWM is like this one.   

http://store.qkits.com/moreinfo.cfm/MXA066
Title: help with DC electric motor (not in Cougar)
Post by: Haystack on January 04, 2012, 03:15:06 PM
I see. I have almost always seen the pulse's sent between three wires going into the motor. Take 12v to the two leads and see if it spins.
Title: help with DC electric motor (not in Cougar)
Post by: Kitz Kat on January 04, 2012, 03:30:55 PM
Did you clean a bare spot for the ground? won't ground to a painted surface. Should work direct the way you describe, unless it's a bad one.