Optoisolated AC Switch (Inductive Load)


Yesterday I posted the circuit for a resistive load circuit and now I’ve just knocked up the circuit for inductive loads. I will be adding in a quick ‘aside’ post explaining the differenct for those that don’t know which will be found HERE.

Ensure you have the correct circuit for your application. NEVER connect an inductive load to a resistive circuit and also bear in mind that the inductive circuit might cause problems with resistive loads. For now, though, remember that parts of this circuit are operating at mains potential and can be extrelmey dangerous or fatal if handled incorrectly. Ensure correct fuses and earthing are used at all times and make sure the power is disconnected before handling any part of the circuit.

In the case of this circuit, pay especially close attention to the capacitor as it may still contain a high charge even after the circuit is disconnected from the mains.

Optoisolated AC Switch Inductive Load

Schematic for an optoisolated TRIAC switch for inductive loads using an MOC-3020 and a BTA16-600B TRIAC.