David Verville wrote: > > Woodworker's supply sells a "Router Speed Control" > for about $40 US. It says it can handle any 120V > DC or universal motor up to 15 amps. > Part Number 821-539 1-800-645-9292 > > Dave Verville > [log in to unmask] Nope doubt it will work ...... First of all if you could use if let's say with a 1hp motor. 1hp=746Watts, divided by 110 volts = 6.78 Amps ...... but you normally have a sart load of about 3X so the start load would be about 20 amps. With the number of starts you would have it would burn up the speed controller very shortly. The real reason that a speed controller won't work is because a speed controller can only work on a motor with brushes, or universal motor. Thats a motor in a normal power tool. An extractor motor, blower motor etc is an induction motor. It uses the windings in the filed and the cycles in the current to control the speed. A two speed induction motor has two set of windings. This type motor will only work on AC current, and won't work with any type of spped controler, dimmer switch or things like that. You need to vary the speed via some mechanical ie transmission technique. Variable pullys, gears or hydraulic is about the only way. Al Welk - Atlanta, GA