Ac fan motor speed control

[Josima]

I am trying to make a variable voltage using a triac,diac,vr,and 2resitors,now I do not have a diac what replacement can I use for diac?
Thanking you

 

[MaxHeadRoom78]

It is advisable to use the diac shown in most circuits.
Max.

 

[alec_t]

I do not have a diac what replacement can I use for diac?

This article by member Dick Cappels may be of use.

 

[Visitor]

Isn't a triac speed controller limited to certain types of motors?

 

[MaxHeadRoom78]

Isn't a triac speed controller limited to certain types of motors?

Generally, yes, typically used on small AC motors, either shaded pole or PSC (permanent start cap) motors.
Usually 1/4HP maximum.
But also used in power tools that use a Universal motor.
Max.