News Center

OPCUA-Modbus test instruction

Release time:2021-03-01 16:56:00Click:

Alotcer industrial gateway supports standard embedded OPC UA protocol, which can convert PLC device data into standard OPC protocol data, and realize the function of OPC system to access diversified PLC device data. Currently, it can be connected to protocol devices such as Modbus RTU, Modbus TCP, and Modbus RTU Over TCP.


Test environment:

LAN test, router local IP (, OPCUA client (, Modbus simulation tool

test tools:

1. Modbus Salve --- Modbus equipment simulation simulation debugging tool

2. UaExpert --- OPCUA's GUI tool

Testing process:

1. Add Modbus type devices (ModbusRtu, ModbusTCP, ModbusRtuOverTCP) in router interface configuration, add device register mapping table (format: register name, data type, register address, register length; data type selection: SByte|Byte|Int16|UInt16|Int32 |UInt32|Int64|UInt64|Float|Double|StringSTRING type is string length, other types greater than 1 will generate an array; eg:reg1,String,1,6;)

2. Set OPCUA server port (default 4840, can be changed according to needs, be careful not to conflict with other ports)

3. Modbus Salve settings

Device1 Modbus RTU setting screenshot

Device2 Modbus TCP setting screenshot

Device3--Modbus Rtu Over TCP setting screenshot

4. OPCUA client configuration

5. After connecting to the OPCUA server, the client generates a device file (registered mapping file), and pulls the file to the Data Access View interface (the data will change with the Modbus device data)