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:

1.  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.
2.  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.
3.  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
4. Turn ON All relays:
   • Send:   FF 0F 00 00 00 08 01 FF 30 1D
   • Return: FF 0F 00 00 00 08 41 D3
5. Turn OFF All relays:
   • Send:   FF 0F 00 00 00 08 01 00 70 5D
   • Return: FF 0F 00 00 00 08 41 D3
6. 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.
7. 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
8. 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.
9. 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.
10. 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.
11. 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.
12. 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
13. 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
14. 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.
15. 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.​

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