4 Relay Module 10A / 250V Opto-Isolated Inputs 3-24V for Arduino etc.

Description

This 4 Relay Module needs a power supply of 5VDC. The opto-insulated inputs can handle 3-24VDC control voltage, with a maximum input current of 22mA at 24VDC.

A jumper can switch between 2 modes:
1. If the jumper cap is set to VCC and JD-VCC, relays and opto inputs are using the same 5VDC power supply.
2. If the jumper is open, a separated 5VDC power supply can drive the relays and the inputs are open for voltages up to 24VDC.

The inputs are LOW-active. It means the output of a microcontroller (like Arduino or Raspberry) draws the input current to GND. The LOW level activates the relay, and a high level (or 3-state level) deactivates the relay.