One channel Modbus RTU relay module equipped with stable 8-bit MCU and RS485 level communication chip,adopt standard MODBUS RTU format RS485 communication protocol. It can realize 2-bit input signal detection and 2-bit relay output. It can be used for digital detection or power control occasions.

Features

• Support Modbus RTU protocol
• Support RS485/TTL UART interface
• Output indicator in multi mode
• Address can be set
• Support input reverse connection protection
• Relay switch output
• Support parameter memory function

Specifications:

• Item name: Single Modbus Relay Module 
• Work voltage:DC 7V~24V
• Baud rate:4800/9600/19600bps(default 9600bps)
• Optocoupler input signal:DC 3.3V~30V
• Set address:1~255
• Relay contorl mode: ON/OFF,Delay_ON,Delay_OFF mode
• Delay time: 0~6553.5s 
• Load: AC 250V 10A or DC 28V 10A
• Protocol: Modbus RTU
• Interface: RS485/TTL UART
• Control channel: 1 channel
• Operating Temperature:-20℃~85℃
• Operating Humidity:5%~95%RH
• Module Size:85*49*19mm

Modbus RTU Command:

• Suppose the device address is 0xFF so return 00 10 00 00 00 01 02 00 FF EB 80 and the 9th btye is device address.
• Turn ON CH_1 Relay(Normal Mode):
  • Send: FF 05 00 00 FF 00 99 E4
  • Return: FF 05 00 00 FF 00 99 E4
  • The 3rd and 4th byte are relay addresses.So it can be 0x0000,0x0001,0x0002,0x0003.
  • The 5th and 6th byte are relay data.0xFF00 means turn ON relay and 0x0000 means turn OFF relay.
• Turn OFF CH_1 Relay(Normal Mode):
  • Send: FF 05 00 00 00 00 D8 14
  • Return: FF 05 00 00 00 00 D8 14
• Turn ON All relays:
  • Send: FF 0F 00 00 00 08 01 FF 30 1D
  • Return: FF 0F 00 00 00 08 41 D3
• Turn OFF All relays:
  • Send: FF 0F 00 00 00 08 01 00 70 5D
  • Return: FF 0F 00 00 00 08 41 D3
• Set device address to 0x01:
  • Send:   00 10 00 00 00 01 02 00 01 6A 00
  • Return: 00 10 00 00 00 01 02 00 01 6A 00
  • Note: The 9th btye is device address.
• Set device address to 0xFF:
  • Send: 00 10 00 00 00 01 02 00 FF EB 80
  • Return: 00 10 00 00 00 01 02 00 FF EB 80
• Read device address:
  • Send: 00 03 00 00 00 01 85 DB
  • Return: 00 03 02 00 FF C5 C4
  • Note: The 5th btye is device address.
• Read relay status:
  • Send: FF 01 00 00 00 08 28 12
  • Return: FF 01 01 01 A1 A0
  • Note:The 4th means which one relay.0 means OFF and 1 means ON.
• Read optocoupler input staturs:
  • Send: FF 02 00 00 00 08 6C 12
  • Return: FF 02 01 01 51 A0
  • Note:The 4th means which one input.0 means low level signal input and 1 means high level signal input.
• Set baud rate 4800bps:
  • Send: FF 10 03 E9 00 01 02 00 02 4A 0C
  • Return: FF 10 03 E9 00 01 C5 A7
  • Note:The 9th btye is baud rate value.0x02 is 4800bps.0x03 is 9600bps.0x04 is 19200bps.
• Set baud rate 9600bps:
  • Send: FF 10 03 E9 00 01 02 00 03 8B CC
  • Return: FF 10 03 E9 00 01 C5 A7
• Set baud rate 19200bps:
  • ​Send: FF 10 03 E9 00 01 02 00 04 CA 0E
  • Return: FF 10 03 E9 00 01 C5 A7
• Turn ON CH_1 Relay(2S Flashing Mode):
  • Send: FF 10 00 03 00 02 04 00 04 00 14 C5 9F
  • Return: FF 10 00 03 00 02 A4 16
  • Note1: The 3rd and 4th byte are relay addresses.So CH1~CH4 can be 0x0003,0x0008,0x000D,0x0012.
  • Note2: The 10th and 11th byte are delay time in second.The minimum delay time is 0.1s.Relay will OFF after delay time.So the delay time in this command is : 0x0014*0.1=2S.
• Turn OFF CH_1 Relay(3S Flashing Mode):
  • Send: FF 10 00 03 00 02 04 00 02 00 1E A5 99
  • Return: FF 10 00 03 00 02 A4 16
  • Note:Relay will ON after delay time.So the delay time in this command is : 0x001E*0.1=3S.