To control air conditioning system in one part of a plant, LEK Ljubljana used outdated SCADA system, which they wanted to renew. The data exchange specification between DOS SCADA system and PLC controller was missing. By analyzing the actual data transfer (Reverse Ingeniering) it was found which information is exchanged and how.

We have developed a DDE I/O server that performs scaling of the data received from existing controller and proper preparation for a new iFix SCADA control system. The server window shows received data and display a log of communication which is under way.