scope:

This standard is applicable to grading capacitors used on circuit -breakers. Their function is to control the voltage distribution across the individual interrupter units of a multi-break circuitbreaker. Grading capacitors can also be used in parallel to the interrupter unit on single break circuitbreakers to modify the Transient Recovery Voltage (TRV). NOTE The grading capacitor is a sub-component for the circuit-breaker and shall be specified in accordance with the circuit-breaker specifications. This standard applies to grading capacitors falling into one or both of the following categories for: - mounting on air-insulated circuit-breakers; - mounting on enclosed circuit-breakers (for example immersed in SF6, in oil, etc...). The testing for each of the above applications is in some cases different. The object of this standard is: - to define uniform rules regarding performances, testing and rating; - to define specific safety rules; - to provide a guidance for installation and operation.