Using Modbus over IP and Modbus RS 232/485 simultanously

As a standard, the CS141 is configured to use either Modbus over IP or Modbus over RS 232 / 485 to serve a modbus master to ensure both, a fast and a stable connection without any timeouts:

• If the hardware interface is disabled or assigned to other devices, Modbus over IP will start.
• If COM 2 (or the Modbus interface) is enabled, Modbus over IP will be automatically disabled by design.

For technical reasons, it may be necessary to use both operating modes in parallel - in this case the CS141 can be configured to serve both connection methods at the same time.

Note:

In some cases, queries running in parallel from different signal sources may cause a timing problem - caused by sporadic time lags, a Modbus master will incorrectly report a timeout. If you are using the simultaneous Modbus operation mode, please ensure to adapt the master's time window so the CS141 has enough time to send an answer.

To activate the Simultan Modbus Request Mode, these menus must be configured:

Step 1: Activate the hardware interface

At Devices, select Modbus at COM 2.

Step 2: Prepare the Modbus Service

In Services > Setup, set the 'Modbus sliding switch' to OFF and click Apply. Wait a few seconds, then enable the service. Please note that the service will only start after clicking 'Apply'. There is no need to restart the device.

Step 3: Configure the interface
At Services>Modbus, search for  “Activate TCP/IP and Serial simultaneously:

Click apply to confirm the settings. The CS141 will restart the service into simultaneous operating mode.