Phase Controller

Thread Starter


Joined Feb 16, 2012
hi all.
i want to build a Phase controller.

i've search the circuit in google. but when i tried to simulate in Multisim 11 (NI, workbench) the circuit wont work??

the main purpose of the circuit, is to controll the power transfered to the load

example : control the heat element

any hint how to make a phase controller? or do sombody have the circuit?

Ac source : 220V, 50hz

Load : about 300kw

thanks for your attention

Thread Starter


Joined Feb 16, 2012
thanks to your reply

yes i'd like to use TRIAC.

but when im trying to make an RC triggering TRIAC. somehow i can't fire it freely from 0° - 180°

and other option i had is by using external dc source for triggering. but i confuse how to make an zero crossover checking so i can made an delay to fire the triac based on zero cross over...

do you have any circuit like that?


Joined Feb 20, 2012

I have made a circuit like this to load and test a 3 phase UPS, around a pic 16f886 worked like a charm.

The way to solve the cero crossing, (at least how I did it) was to take some simple and cheap opto-coupler, put a 4007 diode in series with one phase, a BIG ceramic 10w resistor and the the anode of the led in the opto, the cathode went strainght to neutral.

This will give you a pseudo square wave wich you can work with, feed this to the input pins of your favorite MCU the rest. Hope this is helpfull

Good luck