the pm1205 is an ac solid state switch that uses optical coupling with dual power scr outputs to produce an alternative to optocoupler and triac circuits. the pm1205 switches are robust enough to provide a blocking voltage of up to 500v. in addition, tightly controlled zero crossing circuitry ensures switching of ac loads without the generation of transients. the input and output circuits are optically coupled to provide 3750v of isolation and noise immunity between control and load circuits. as a result the pm1205 is well suited for industrial environments where electromagnetic interference could disrupt the operation of electromechanical relays.