wancoz;
If the Motor planned to be Speed Controlled is a Split Phase Induction Type (single phase Motor with a "Start Switch and Winding"), this should not be attempted.
Reason being that the Start Switch will engage the Start Winding at speeds of Apx. 80% (and lower) of the Motor's Full Speed.
When this occurs, the Start Winding remains active in the Circuit until the Switch re-opens.
The Auxiliary (Start) Winding draws a high level of Current, and if kept active for an extended period of time (like more than 30 Seconds), chances are the Winding will fry, the Breaker / Overload unit will trip, or both will occur.
If the Motor is a PSC (Permanent Split Capacitor) type, or a Shaded Pole type Induction Motor, then these may be Speed Controlled without damaging the Auxiliary Winding.
Just some FYI!
Scott35
