The switching commands to the controllable switchgear units in the bay are enabled only after interlock conditions have been checked. The interlock conditions are defined in the form of Boolean equations in the interlocking logic function.

The choice of the bay type automatically defines the bay interlock conditions (or equations) for the ‘Open’ and ‘Close’ operations of the individual switchgear units in the bay. The bay interlock equations for operation with station interlock differ from the bay interlock equations for operation without station interlock (see Chapter “Key to the List of Bay Types”, Chapter “List of Bay Types”). These automatically defined interlock conditions – determined by the choice of bay type – can be modified by the user at any time to fit particular station requirements. The following signals acquired by the P632 are linked by logic operations for the bay interlock:

A maximum of 32 equations with 32 equation elements each are available to define interlock conditions. The Boolean equations need to be defined without the use of brackets. The following rule applies to the operators: “NOT” before “AND” before “OR”. The output signal of one equation can be fed into a higher-order equation as an input thus creating a sequence of interlinked Boolean equations.