FAST/TOOLS is successful in critical applications due to its very stable design, support of redundant and fault tolerance systems and its very high performance on-line configuration possibilities. These properties contribute to high efficiency and high quality production processes. One aspect of SCADA system is the impact of performance of the total SCADA configuration. The follow story gives some performance figures. The performance test was executed on a typical FAST/TOOLS configuration with SCADA server and Operator Stations (clients)