motor control

hiii every one,
I have one low power 150W single phase motor and need to be controlled its speed.Is there any way of controlling its speed without inverter drive.I am not using any Plc for my application.pls advise me in this case.

It depends on how precise and what your budget is...

You could go for something as cheap and cheerful as the device below (requires a triac etc to complete it)..

http://docs-europe.electrocomponents.com/webdocs/0559/0900766b8055906a.pdf

...or spend a little more on a purpose made unit that you just connect mains in and motor out...(the above is approx £8 Sterling)

Hope this may help!

Kid Blue:

The description says: "This is unsuitable for use on inductive loads."

Motor = inductive load.

Have you tried using this electronic regulator on a motor load? Perhaps it might work with a very small 150 watt motor.

Oops! Didn't check the spec fully! I have used that principle before (but rolled my own triggering cct) - and it seemed to work fine (small drill motors etc). The only thing i added was a snubber cct across the load....

I was looking for a link to the module i had come across before but couldn't find it. I know they're readily available for this exact application.

Sorry for the duff data!!

Don't be sorry, because it may still work. If you did it before with a drill, then that's good enough for me. The circuit in the link shows connecting the phase regulator to a triac, and the triac does the switching of the voltage to the motor, so for a small motor, I can see that it just might do the trick.

Drill motors from power tools and other brush type motors are not considered inductive loads due to their rather low selfinductance(?). Phase shift does not occur, so triac voltage regulators work really well. And their speed can be easily controlled by changing the applied voltage.

It's a whole other issue with asynchronous (PSC) motors. Their speed is not proportional to the applied voltage: The frequency determines their speed. However for some applications (with exponentially changing loads) like fans and blowers, a voltage regulator does work. For all other load types, it does not.