Where a third-party server uses the Modbus protocol to obtain data from ClearSCADA, and ClearSCADA uses the Modbus protocol to obtain its data from a PLC, ClearSCADA becomes dual-purpose, with regard to Modbus functionality. When communicating with the third-party server, ClearSCADA acts as a Modbus Slave, and when communicating with the PLC, ClearSCADA acts as a Modbus Master.
In this scenario, you need to configure both a Modbus Slave and a Modbus Master configuration suite. You also need to check that ClearSCADA is running both the Modbus Slave driver and either the Advanced Modbus driver or the simple Modbus driver (whichever is applicable).
To configure ClearSCADA so that it can communicate as a Slave, see Configuring Modbus Slave Devices in ClearSCADA.
To configure ClearSCADA so that it can communicate as a Master, see the ClearSCADA Guide to the Advanced Modbus Driver, or the ClearSCADA Guide to the Simple Modbus Driver (as applicable).
