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Triac Control


Warning! Any voltage above 30 is considered unsafe. While the circuits presented here work and are safe, they are not guaranteed to be. Exercise your own caution when using these designs as I will not be held liable for any injury.



On off control from low power/voltage switch or microcontroller. C1 and Q7 must be high voltage. Q7 needs only be able to pass 100mA. The switch S1 controls everything. For a door light control make the switch a magnetic one connected to the door. For microcontroller control, replace S1 with a general purpose NPN transistor (ie 2n2904). The U1 optoisolator can be any lower power model.