Gable fan motor like this, 1/5 HP, 396 watts; 6 poles; two wires; doesn’t spin real fast.
I’m using it in an exciting new heat flow application (pix to come!), and a variable speed function with a normal light dimmer would be great, though not essential.
Anyone know, before I just experiment and let the smoke out?
Forrest – not an electrimatrician
Replies
It will work if you have a big enough dimmer, although an old fashioned variable iductance dimmer would work better than the semiconductor type (almost all of them these days)
On thing to remember is that fan load is a function of the cube of the speed, so if you start it off at zero and turn it up to the speed you want it should be OK and avoid the inrush current (good change of burning out the semiconductor dimmer if you just turn it on as say 1/2 setting).
Changing the dimmer setting affect the motor speed as the reduced equivalent voltage causes a higher motor slip (and causes it to become more ineffecient), but due to the cube function you wont burn out your dimmer as long as you don't try to start it at partial loads.
Okay, sounds like I need to get a dimmer that rotates all the way CCW to click "off", not a push on-off.
That would assure always ramping it up to speed, no?
Forrest
Edited 12/11/2007 1:34 pm by McDesign
I would get 3 speed ceiling fan "controller". They are available at the home horror stores for about the same price as the dimmers. I think that they use inductors.But check the ratings on them.Some are designed to run multiple fan..
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
Hey - there's an idea - thanks!
Forrest