Optically Isolated Phase Controlling Circuit

[dhanush]

Try this way it should work.

Than place an oscilloscope on pin 2 of LM555 and you should see a pulse every 8,3 milliseconds (if your main is 60 Hz) or every 10 milliseconds ( if your main is 50 Hz)

Al.

Thank you so much aratti.

Ok I am going to build with your way, but I like know that what are the problems in my circuit, you said H11L1 is on all time, so zero crossing detecter should not work. When I am looking your way, the main differents is you are not avoiding zener diode (D5) and H11L1 parallel resistor (R2) right? On EFY Magazine circuit both components are not using, but that is working circuit. For getting knowlege, can you please explain why zener diode (D5) and resistor (R2) is used in this circuit?

And also please tell me, if I want trigger upto twenty five LM555 for controlling upto 25 fan, which transistor I need to use instead of MPSA40. Is this transistor has enough current to trigger upto 25 LM555?