The photo relay is designed for automatic switching of lighting when ambient light levels decrease (at dusk).
A phototransistor S1 is used as the light-sensitive sensor. The integrated circuit U1D operates as a voltage comparator, comparing the ambient light level with a preset threshold.
The relay switching threshold can be adjusted using trimmer potentiometer TR1. An LED provides clear indication of the relay status and shows when the relay is activated.
The photo relay is suitable for controlling outdoor and indoor lighting, advertising signs, and other systems requiring automatic activation in low-light conditions.

Technical Specifications:
Light sensor: phototransistor.
Operating mode: voltage comparator.
Adjustable switching threshold.
Indication: LED.
Supply voltage: 10 - 16V DC.
Current consumption: up to 100 mA.
PCB dimensions: 51 x 46 mm.

This product is a DIY assembly kit.
It is also available as a fully assembled module - Product code 1573 (separate product).