Hi,

I attach a simple circuit about the triac acting as the switching element for an AC load. What I want to point out is that I usually see that Main terminal 2 is connected to the hot line. Is there any particularity in connecting the main terminals (MT1 and MT2)? Are they interchangeable? Triac is a PNPN device, so I think it's not symmetrical.

 

https://electronics.stackexchange.c...m-microcontroller-using-4n35-optocoupler?rq=1
Max.