How to Use:
1. The photoresistor module is more sensitive to ambient light, and is generally used to detect changes in the brightness of the surrounding ambient light.
2. Red light: module work, blue light: relay work instruction, potentiometer: adjust the detection brightness value (recommendation of physical test fine‑tuning).
3. When the ambient light of the module is darker than the threshold, the relay is closed, and the common terminal is connected to the normally open terminal (disconnected from the normally closed terminal). When the external light is brighter than the set threshold, the relay is disconnected, and the common terminal is connected to the normally open terminal. Disconnect (connect with the normally closed terminal).
4. The three ports of common terminal, normally open terminal and normally closed terminal are equivalent to a ‑control switch. When the relay coil is energized, the common terminal and the normally open terminal are conducted; when there is no power, the common terminal and the normally closed terminal are conducted.
5. A in the middle of the output terminal is the common terminal, the upper part is the normally open terminal, and the lower part is the normally closed terminal.

Specification:
Item Type: Photoresistor Relay Module
Model: XH-M131
Working Voltage: 5V
Output Mode: One Output
Sensor Cable Length: Approx. 30cm / 11.8in
Machine Size: Approx. 53 x 31 x 19mm / 2.1 x 1.2 x 0.7in

Package List:
1 x Photoresistor Relay Module
1 x Light Sensor