Relay Module Reference
Electrically operated switch
Pin names
| Name | Description |
|---|---|
| VCC | Supply voltage |
| GND | Ground |
| IN | Control signal (e.g. from micro-controller) |
| NC | Normally closed |
| COM | Common pin |
| NO | Normally open |
Operation
The relay is an electronic switch.
When the IN pin is low / disconnected, COM is connected to NC (NC means normally closed).
When the IN pin is high, COM is connected to NO (NO means normally open).