Patent ID: 6870719

Claim:
A method for the plausibility checking of current transformers in an electrical switchgear, the switchgear being controlled by a control system and measurement signals from current transformers arranged at at least two different measuring points being processed by the control system, wherein, for testing the plausibility checking of the current transformers, an instantaneous topology of the switchgear is detected by the institution control system based on existing electrical connections of primary devices and based on instantaneous positions of switches, based on the instantaneous topology, at least one zone of the switchgear is identified, which zone represents a conductively connected area which is bounded by at least one current transformer, in the zone, the measurement signals of the current transformers are detected with a current-direction-dependent sign and are added to form a current sum of the zone, and if there is a current sum which is not equal to zero within a permissible current transformer measuring accuracy, all current transformers of the associated zone are identified as being problematic.