2 Questions about electric motors

[Michael]

Hi,

1.
I have a 36v motor that i need to control. I thought abouit using multiple
6v batteries, then stepping up the voltage. Would this damage the motor?
2.
At what level is it best to run a motor at, in terms of % if stall was 100%?

Thanks

Michael

 

[Don Kelly]

----------------------------
"Michael" <miQchaelQhQims@Qblueyonder.co.uk> wrote in message
news:2zref.8886$Lw5.7039@text.news.blueyonder.co.uk...

Hi,

1.
I have a 36v motor that i need to control. I thought abouit using multiple
6v batteries, then stepping up the voltage. Would this damage the motor?
2.
At what level is it best to run a motor at, in terms of % if stall was
100%?

Thanks

Michael
---

How you control the motor is somewhat dependent on how large it is and what
you are using it for. You can get crude step control by using 3,4,5, or 6
batteries in series- for small motors. At lower voltages, the control will
not be particularly effective as the available torque drops. A source of 36
to 40V with an electronic control will work well or, if the motor is small
enough (and a 36V motor may well be too large) use of resistance control.
I assume that this is a permanent magnet DC motor or you can separate the
field from the armature circuit if a shunt motor.

As for the level of operation - depending again on the motor, the best
operating point is at a load well below stall -say under 30% of stall
torque. It depends on the motor characteristics and type but for a PM DC
motor or separately excited motor, the peak power output will be at about
50% of stall torque and current.

--

Don Kelly @shawcross.ca
remove the X to answer

 

[JeffM]

I have a 36v motor that i need to control.
I thought abouit using multiple 6v batteries,
then stepping up the voltage.
Michael

http://www.google.com/search?q=defineulse+width+modulation
http://groups.google.com/groups?q=ingroup:sci.electronics.*+pulse-width-modulation+motor