Configuration of MODBUS TCP/IP Server Settings

As of Automation_Builder 1.1 (CBP 2.4.) MODBUS configuration has been moved to another location within the device tree. Note: Principle of MODBUS configuration remains unchanged.

Configuration up to CBP 2.4

Double-click on MODBUS_on_TCP_IP (MODBUS on TCP/IP) to open the MODBUS TCP settings in the editor window:

Configuration as of CBP 2.4

For MODBUS TCP/IP protocol configuration add a new object for MODBUS Server settings under Ethernet Interface ‣ Protocols. In

the device tree double-click the new added item to open the configuration:

Parameters

Depending on the Automation_Builder/CBP version some or all parameters are available:

Parameter	Default	Value range	Description
Server connections	0	0…X (X depending on CPU)	Maximum number of logical server connections allowed in parallel. 0 means only client usage (MODBUS Master). Requests from other clients are ignored.
Task timeout	2000	100…6000000	Used for client mode only: A request is cancelled if no reply from the server is received during the time given in task timeout [in ms].
OMB time	1000	100…6000000	Used for server mode only: determining how long a logical connection in [ms] remains after receiving the reply message of a client. Establishing and terminating of connection takes some time. When the data communication between the controller and the servers should take place only at long intervals, it is useful to close the connection immediately after completion of the data communication.
Send timeout	0	0 … 2000000000	Used for client mode only: definition, how long [in ms] the PLC tries to send a request to a server. CM579-ETH: 0 is default value 31000 ms Onboard ETHERNET: not implemented
Connect timeout	0	0 … 2000000000	Used for client mode only: definition, how long [in ms] the PLC tries to establish a TCP connection with a server. CM579-ETH: 0 is default value 31000 ms Onboard ETHERNET: fixed value 18000 ms
Close timeout	0	0 … 2000000000	Used for client mode only: definition, how long [in ms] the PLC tries to quit a TCP connection with a server. CM579-ETH: 0 is default value 31000 ms Onboard ETHERNET: not implemented
Byte order	Big endian	Little endian	Valid for client and server mode. Format for the transmission of WORD values (register) within the telegram.
		Big endian
Set default values	-	-	Restoring the default values of all parameters.