LC 4 channel Modbus relay module equipped with mature and stable 8-bit MCU and RS485 level communication chip, adopts standard MODBUS RTU RS485 communication protocol. It can realize 4-bit input signal detection and 4-bit relay output. It can be used for digital detection or power control occasions. Features: 1. Support Modbus RTU protocol 2. Support RS485/TTL UART interface 3. Output indicator in multi mode 4. Address can be set 5. Support input reverse connection protection 6. Relay switch output 7. Support parameter memory function Parameters: 1. Item name: 4CH Modbus Relay Module 2. Working voltage: DC 7V~24V 3. Baud rate: 4800/9600/19600bps (default 9600bps) 4. Optocoupler input signal: DC 3.3V~30V 5. Set address: 1~255 6. Relay control mode: ON/OFF, Delay_ON, Delay_OFF mode 7. Delay time: 0~6553.5s 8. Load: AC 250V 10A or DC 28V 10A 9. Protocol: Modbus RTU 10. Interface: RS485/TTL UART 11. Control channel: 4 channel 12. Operating temperature: -20C ~ 85C 13. Operating humidity: 5% ~ 95% RH Color: Blue Material: PCB Size: 93 x 90 x 20mm Package Contents: 1 x Modbus RTU 4 Relay Module Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item to be slightly different from the real thing. The measurement allowed error is +/- 1-3cm.