I am driving a Triac using the MOC3083. The triac is switching a Contactor 230Vac. When switching ON is ok but when switching Off the Contactor stays energized.
If the Opto is removed the Triac switches OFF so the problem seems leakage on the Opto triac.
If the MOC3083 is replaced by MOC3063 this works fine.
On datasheets I did not find any differences between the two optos other than the working voltage.
I have tried 3 different parts with the same result. I have just bought them from Farnell - actual part number is MOC3083X.
Using a light bulb as a load the circuit works fine. I am using ACST830-8 Triac then a 470R resistor from OUT pin to opto then to Gate.