The ConPerMon function block evaluates the set point, the process value and the manipulated value of the PID controller in a sliding time window. With the process in a steady state, the detected stochastic characteristics are compared with the reference values obtained during commissioning. If there is a step change in the set point, the stochastic characteristics are by definition irrelevant and are temporarily frozen. Instead, the monitoring of the deterministic characteristics is automatically activated. If the control performance falls below a defined limit a message is generated. This is also the case when a defined limit for overshoot is exceeded when there is a step change in the set point.