Originally Posted by flatulentfox
Many of the cheaper 40A SSRs I have looked at mention nothing about being zero crossing. At the frequency most of us are switching (around 1hz), is this much of an issue? Will a zero crossing SSR have a longer life? In theory, It will never interrupting much current, seems like this would be better for it...
Also, does this include zre crossing at turn off as well as turn on?
Zero crossing isn't a concern for the SSR - just the equipment being driven. In our case, a heating element doesn't give a hoot about where in the AC waveform it gets energized, so zero crossing SSRs are of no real value to us, but they are pretty standard. Probably harder to find non-synchronous ones, really.