Thyristor-output photocouplers are used to control AC loads that are directly connected to a 100-Vac or 200-Vac commercial power supply or to protect power supplies, etc. against overvoltage conditions. An AC load of several amperes to several tens of amperes can be controlled with an LED current of 10+ mA by using a thyristor-output photocoupler in tandem with a power triac.
