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Modbus

The Modbus North Connector enables OIBus to write data to Modbus-compatible devices, allowing seamless integration with PLCs, RTUs, and other industrial equipment that supports the Modbus protocol.

Example Use Cases

  • Process Control: Write setpoints and control values to PLCs
  • Configuration Management: Update device parameters remotely
  • System Integration: Bridge OIBus data with Modbus-compatible equipment

Specific Settings

Connection Configuration

SettingDescriptionExample Value
HostIP address or hostname of the Modbus server machine.192.168.1.100
PortPort to use for connection (502 by default).502
Connection timeoutMaximum time to wait for a connection (in milliseconds).10000
Retry intervalTime to wait (in milliseconds) between reconnections after a connection failure.5000
Slave IDIdentifies the Modbus source machine (default is 1).1
Address offsetFor most PLCs, there is no offset (Modbus option). Some PLCs may start the address range at 1 instead of 0 (JBus option)Modbus

Data Format Options

SettingDescriptionExample Value
EndiannessType of bit encoding.Big endian
Swap BytesWhether bytes within a 16-bit word should be swapped.Enabled/Disabled
Swap WordsWhether 16-bit words should be swapped within a 32-bit group.Enabled/Disabled

Use the tester below to preview how different endianness and swap settings affect the byte layout of a value written to a Modbus register:

Register 1
0x
Register 2
0x
Byte pipeline
From registers (Big Endian)
4120
R1
0000
R2
Float10

Presets