I have the above question and I don't know who to ask. I looked around here, while most have no answers but there are a couple that kind of applies but went a little over my head, like these: 1) https://electronics.stackexchange.com/questions/304450/directly-controlling-an-ac-load-with-a-power-phototriac 2) https://electronics.stackexchange.com/questions/98698/control-ac-load-with-microcontroller-triac-behaviour-problem I am trying to control various AC loads (240V, 1000W) with a microcontroller GPIO pin. I found [this][1] tutorial online and I want to just follow it. But I don't know how to find the right components, provided the circuit works. (1) For U1, I want to use MOC3021 optoisolator, will that be OK? (2) For U2, I want to use BT134-600 triac (600V, 4A), will that be OK? (3) How do I size R1 and R2, can I use just those same values? I apologise in advance if this question is too simple/stupid. Thanks. [![enter image description here][2]][2] [1]: https://components101.com/ics/moc3021-triac-driven-optoisolator-pinout-equivalent-datasheet [2]: https://i.sstatic.net/9u7Nt.png