AC Mains Detector Circuit

Published at : 23 Dec 2025

High-Quality PCB prototypes: https://www.pcbway.com

Have you ever felt the need of a circuit that can detect whether AC power is on or not? Well, here your wait ends. This simple circuit can detect AC power easily and safely and uses very less parts. Take a look at the video and see for yourself.

Pictures, Circuit Diagram and more: https://www.instructables.com/AC-Mains-Detector-Circuit/
Another circuit: https://www.electroschematics.com/mains-voltage-sensor/

Parts:
INDIA:
DB107 Rectifier - https://amzn.to/3wJPa6H
PC817 Opto-Coupler - https://amzn.to/3wK6jNx
150k 2W Resistor - https://www.electronicscomp.com/150k-ohm-2-watt-resistance

US:
DB107 - https://amzn.to/3MHOJAr
PC817 - https://amzn.to/3yTRzOY
150k 2W Resistor - https://amzn.to/3lysUYe

UK:
DB107 - https://amzn.to/3NuG44r
PC817 - https://amzn.to/3PCBiny
150k 2W Resistor - https://amzn.to/3PvRFC6