Master-Slave-Arrangement

Configuring the Master

To configure the CM574-RCOM as a master device the parameter “Operation mode” must be set to “RCOM Master”. The address or node number must be set to 0 while “Parity” should be “None”. Ensure that “Hayes compatible dial modem” is selected as “Type of modem”. The “Character timeout” should be set to 50 msecs. The value for the “Turnaround time” should be increased to 6000 msecs.

If the CONSOLE port is used (recommended) the parameter “Debug level” of module “CONSOLE” should be set to “Level 2” to obtain detailed information and error messages of the protocol.

Configuring the Slave

To configure the CM574-RCOM as a slave device the parameter “Operation mode” must be set to “RCOM Slave”. The parameter address must be set to a value greater than 0. In this example select 1 for the slave. “Parity” should be “None”. Ensure that “Hayes compatible dial modem” is selected as “Type of modem”. The “Character timeout” should be set to 50 msecs. The value for the “Turnaround time” should be increased to 6000 msecs.

If the CONSOLE port is used (recommended) the parameter “Debug level” of module “CONSOLE” should be set to “Level 2” to obtain detailed information and error messages of the protocol.

Configuring the Modem

The example uses ABB H&IT HSM-ECO Remote Modems that provide the ability to use both operation modes, RCOM and RCOM+.

Setting up the Phone Book

For both projects the telephone numbers of the RCOM devices must be configured. To use a dial-up modem, a corresponding module has to be appended to the RCOM/RCOM+ module in the PLC configuration as described in the PLC configuration steps of the CM574-RCOM AC500 PLC Configuration: AC500 PLC Configuration AC500 PLC Configuration.

Note

For consistency reasons, the phone book of the master as well as the phone book of the slave(s) must be equal.

To add a new entry to the phone book, append a telephone number to the modem. The tab “Module parameters” provides the possibility to set up the corresponding dial prefix identifier and the corresponding telephone number of the node that should be configured.