Modbus configuration

Modbus configuration settings.

Modbus configuration 1:
Configuration via HTML pages - Modbus configuration

Modbus Device

All parameters are "read only" and are for the purposes of diagnosis only.

Modbus Settings

Settings can be made here for the Modbus interface.

Watchdog Mode (0x1122)

You can choose between Disabled, Telegram and Write here. The watchdog is activated with the first write telegram to the process data; write access is given to the master that was the first to execute a write access to the process data.

The setting is also to be written via the Modbus Interface Offset 0x1122.

Watchdog Timeout (0x1120)

The timeout in [ms] is to be entered here, recommended values 500 ms - 5000 ms; smaller values are not recommended because this can very quickly lead to a watchdog error. The maximum value is one minute.

Writelock (0x1124)

Enables writing from a second master (client) also. Note that only the first master triggers the watchdog when writing from a second master. Furthermore, also pay attention to overlapping write commands.
Sample: if a master sets the first digital output to TRUE and the second Modbus client sets the first output to FALSE, the output will be switched on and off continuously.

Fallback Mode (0x1123)

The fallback mode is only active if watchdog mode is also activated. You can choose here between "Freeze" (outputs are retained) and "Set to Zero" (outputs are written to zero).

Enable ModbusTCP

Activate or deactivate the ModbusTCP protocol.

Max. TCP connection

Number of simultaneously used TCP connections. It is recommended not to allow more than 3. The more TCP connections, the worse the performance of the coupler.

Enable ModbusUDP

Activate or deactivate the ModbusUDP protocol.

TCP/UDP-Port

TCP or UDP port number of the Modbus communication.

Ethernet statistics

Displays the statistics for the incoming and transmitted Ethernet frames.

IP Stack statistics

Displays the IP statistics.

Modbus Service statistics

Displays the Modbus statistics (see also Diagnosis Function 8).