AC Dimmer Safety: Mains Voltage, Isolation, and Wiring Feb 26, 2026 0 18 FAQ TL;DR: AC dimmer modules use optical isolation — the MCU-side pins (ZC, DIM, VCC, GND) are electrically separated from 230V mains. The AC terminals (AC-IN, AC-N, AC-OUT) are live mains voltage. Size w... ac-dimmer safety theory tutorial Read more