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[on:]

Hi,
    I am following this tutorial about  ac phase control with the arduino: http://playground.arduino.cc/Code/ACPhaseControl

  Quote from the tutorial :

This sketch uses a 'Random Phase' or 'Non Zero Crossing' SSR (Im using the Omron G3MC-202PL DC5) to act as an A/C switch and an opto-isolataed AC zero crossing dectector (the H11AA1) to give us a zero-crossing reference"

My local store sells the H11AA1 , but there seems to be no Non Zero Crossing SSR. I just need to know if I could any of the SSR available on the website: http://www.abra-electronics.com/search.php?search_query=Solid+state&x=0&y=0



Thank you

[Reply #1 on:]

A zero crossing SSR only turns on or off when the AC wave is at zero volts. A non-zero crossing SSR can turn on at any point, but again can only turn off when the AC is at zero volts.

If you're trying to dim a light or speed control a universal motor then you need the non-zero crossing type. If you're controlling a heating element then it's really not necessary; you can get enough granularity switching the element on/off 120 times/sec. It depends on the application.

Probably worth mentioning that you just need a triac and an optocoupler to replicate an SSR. Here's an example of an AC dimmer project. I'm sure you can find many more out there.

[Reply #2 on:]

Ok Thank you! and it is way much simpler than the Arduino website.  Can I use a "standard" triac instead of the BT139(snubberless triac?)

[Reply #3 on:]

Don't take this for the absolute truth, but I think I can. I will try it with TIC246D Transistor Triac 16A 400V.

[Reply #4 on:]

Yes that looks a suitable Triac to try.