1CH Active H/L 3V OptoCoupler Relay Module

Relays are always good to have especially for electronics projects. The relay itself offers two main benefits:

• Isolation of low voltage system against high voltage system, example 5VDC and 240VAC
• Allow electronics with low voltage to control high power load, for example from Arduino to AC light bulb.

This is not an ordinary Relay breakout. It comes with 1 (single) channel 3.3V activation relay, ready to control 250VAC at 10A. Extra isolation with optocoupler at the front of control and the activation logic for the relay is configurable via a mini jumper. In simple words, the relay can be configured as 3.3V(High) activation or 0V(Low) activation. This is the universal Relay breakout board and we like it.

It comes with three (3) screw terminals for the relay output:

NO (Normally Opened),
NC (Normally Closed),
COM (Common),

and screw terminals for the control signal from a microcontroller such as Arduino or micro:bit. The control signal is optoisolated, protected. It even comes with power and activation indicator LEDs for the relay. Easy to use and suitable for beginners, and of course students too.

Input power and signal:

• DC+ = +3.3VDC
• DC- = GND (Ground or 0V)
• In1 = Control signal, 3.3V as logic High; 0V as logic Low

If you need to control AC or high current, high voltage load, this will be the perfect board.



Note: We notice the DC+ and DC- need to be 3.3V and the In1 (control signal) needs to be 3.3V or Ground to make it works properly.