LC 4 channel Modbus relay module equipped with and stable 8-bit MCU and RS485 level communication chip,adopt standard MODBUS RTU format RS485 communication protocol. It can realize 4bit input signal detection and 4bit 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.Work 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 contorl 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: 4channel 12.Operating Temperature:-20 Celsius~85 Celsius 13.Operating Humidity:5%~95%RH colour: blue Material: PCB size: 93x90x20mm Package Contents: 4 x Modbus RTU 4 CH Relay Module Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.