I suspect what you have is a "universal" AC/DC motor. They are not synchronous, so changing the line frequency will not change the speed, except as it might affect power or efficiency. Check out "universal motor" on Wikipedia.

The phase controls that you mention (diac, triac, scr) are to slow the motor (edit:delete this, not speed it up). Basically, you reduce the power supply, so the motor slows down. Unloaded, they usually have very high speed. In fact, some will self destruct, if operated completely unloaded. For low power, some people just use a light dimmer.

Another way to slow it down is with a transformer or Variac.

John

 

I have asked many questions... I've built the circuit and it's ready to be used. I'm wondering what happens if the hot and the neutral lines were reversed. I read this http://www.allaboutcircuits.com/vol_3/chpt_7/6.html and other information about triacs, the circuit may not work if the lines are reversed, but I what to know if any part will be damaged or no.

Regards,
Hazim

 

Nothing will happen if Live and Neutral is reversed, except in the case of a neutral ground which are found is old TV's