AC Mains Detection

• AC Mains Detection - https://learn.edwinrobotics.com/230v110v-ac-mains-detection-using-arduino-raspberry-pi-and-esp8266-thing/#Step2
• LTV8141

>

• 掉电检测 - https://www.amobbs.com/thread-5738481-1-1.html

Function of Zero-Crossing

• Delay to connect the AC mains to the target load, so the load receive less power, this can be used to control speed / light
• Active relay on Zero-Crossing, to protect relay and target load, avoid high power shutdown feedback.