Photosensitive resistance sensor relay module LDR Relay

The Photosensitive resistance sensor relay module, also called an LDR relay module, combines a light-dependent resistor (LDR) with an onboard relay. When the light level crosses the switching point, the relay turns on or off, so it can control a lamp, fan or other load automatically at dusk and dawn. It works on its own without a microcontroller, which makes it a simple choice for automatic lighting, and it can also be used inside Arduino and ESP32 projects.

Photosensitive resistance sensor relay Specifications

• Light sensor: photoresistor (LDR)
• Output: relay contacts for switching an external load
• Operation: standalone, the relay switches automatically with the light level
• Typical use: day/night switching of lights and small appliances

Photosensitive resistance sensor relay Applications

• Automatic garden, street and night lights
• Turning porch or shop sign lights on at dusk
• Light-activated alarms and indicators
• Daylight-controlled fans, pumps and displays
• STEM demonstrations of light sensing and relays

What's in the Box

• 1 × LDR photosensitive relay module

Tip: Check the module's rated supply voltage (5 V and 12 V versions exist) and the contact rating printed on the relay before connecting a load. If you switch 230 V mains, use insulated wiring and a closed enclosure, and point the LDR away from the lamp it controls so the light does not switch itself off.

Orders placed before 14:00 are ready for pickup the same day. Delivery across Lebanon usually takes 1–3 working days.