I'm using an optoisolator triac (MOC3021) for switching a DC12V coil Relay. optoisolator triac Input is a digital 2.5V signal connected with a 68ohm series resistor. Isolator Load vlotage is 12V and about 30mA (normal coil relay).
when the signal is "ON" (+2.5V) the optoisolator is triggered and and it also trigger Relay But when the signal is go "OFF" the Relay Stay ON continuously.
I have disconnected the Isolator signal completely, nothing changed. relay stays ON until I disconnect 12V power. when I reconnect it All, the relay an triac is off until 2.5V signal activated and again the triac and relay stay continuously ON.