Applies To:
  • CitectSCADA 5.xx

I would like to setup Citect to talk to a Premium (or Micro) via the UNITE Protocol, but I am unsure as to the exact procedure.

The UNITE driver is an implementation of Unitelway over TCP/IP. It allows Citect to communicate to Premium PLC's over an Ethernet connection. It also allows Citect to communicate to the Micro PLC over Ethernet using the ETZ module.

Below is the recommended method for communicating with a Premium PLC with the ETY module:

Using PL7 software, configure the hardware with an appropriate IP address and Xway address. In this example, an IP address of is used, and an XWAY address of 1.3 (Network = 1, Station = 3).
Ensure you can use the XIP driver from Schneider to communicate to the PLC. If this does not work, it is likely Citect will also have problems communicating.
Once you have successful communications with the PLC via XIP you are ready to configure the Citect system.

Run the IO Express setup wizard.
Create or use an existing IO Server (remember you can only have 1 IO server running on 1 PC).
Create a name for the IO device ( say “PremiumETY” etc...)
Select External IO device.
Now from the Driver list, select the Telemechanique folder, and expand it, then expand the Premium and Micro folder, and select Ethernet (TCP/IP). Click next.
Enter the IP address of the ETY (or ETZ module) making sure it is the same as configured using XIP or PL7 software. Enter 502 in the port field. By default UNITE uses port 502 for session connections. TCP should be selected. Click next. Click next again, then finish.

Now check that the Ports, Boards and IO Device forms in the Project Editor match these settings (or similar for your project):

Board Type: TCPIP
Board Address: 0
Port Name: Port1
Port Number:
Port Baud Rate:
Port Data Bits:
Port Stop Bits:
Port Parity:
Port Special Option: -i84.0.1.14 -p502 -t
Unit Name: PremiumETY
Unit Number: 1 (must be unique number for each IO device)
Unit Address: 1.3.0 (Network.Station.Gate)
Unit Protocol: UNITE
Unit Port Name: Port1

Here is an example of a variable tag pointing to %MW1:
Variable Tag Name: MemoryWord1
Data type: Integer
I/O Device Name: PremiumETY
Address: %MW1

See online help for data types that are supported by the UNITE driver.

The next step is to configure a Network, Station and Gate number for the CitectSCADA PC. To do this add the following lines to the Citect.ini file:
Station=1 (Each device on the Network must have a unique Station number)

After these changes are saved to the citect.ini file, shutdown Citect (both Explorer and Runtime) for the changes to take effect.

Pack and compile your project.
Run the project. You should now have successful communications with the Premium.

UNITE, Unitelway, TSX, Premium, Telemecanique