Size: 75mm (length) x 55mm (w) x 19.3mm (height) Weight: 58g Pcb color: blue board four weeks with four screw holes, hole diameter 3.1mm, easy to install and fixed 4-channel relay control board module with an optocoupler, 4-way relay module for...
The relay module is an electrically operated switch that allows you to turn on or off a circuit using voltage andor current much higher than a microcontroller could handle. There is no connection between the low voltage circuit operated by the microcontroller and the high power...