This AC dimmer module uses phasecut control to regulate power delivered to incandescent lamps, dimmable LEDs, and AC motors, making it ideal for smart lighting, fan speed control, and home automation projects. Its optocouplerisolated design and microcontroller-friendly logic allow safe interfacing with Arduino, ESP32, and Raspberry Pi.
| Pin | Function | Description |
|---|---|---|
| VCC | Control Power | Connect to 3.3V or 5V from MCU |
| GND | Control Ground | Connect to MCU GND |
| PWM/Signal | Dimming Input | Receive PWM or trigger signal |
| AC-IN | Mains Input | Connect to live and neutral of AC supply |
| AC-OUT | Load Output | Connect to lamp or motor |
| Zero-Cross | Detection | Provides AC zero-cross reference for synchronization |
## Key Features
+PhaseCut Dimming Controls power by chopping the AC waveform
+Isolated Control Circuit - Protects microcontroller from AC mains
+DualLoad Support Works with both lighting and motor applications
+RBDdimmer Library Support - Simplifies coding with functions like setPower() [citation:7]
+ESPhome Compatible - Some models natively support Home Assistant integration [citation:10]
√ Works with Arduino, ESP32, ESP8266, Raspberry Pi
√ Compatible with 110V and 220V AC mains
√ Library support simplifies dimming control
Safe connection guide:
For zero-cross synchronization, some modules require a separate connection to a hardware interrupt pin [citation:4]. The RBDdimmer library handles this automatically [citation:7].
## Troubleshooting
| Issue | Possible Cause | Solution |
|---|---|---|
| Load does not dim | Non-dimmable load | Use incandescent or dimmable LEDs |
| Flickering at low levels | Incompatible LED | Increase minimum dimming level |
| Module overheats | Load exceeds rating | Reduce load or upgrade dimmer |
| No response to signal | Wiring error | Verify MCU connections and power |