scope:

This part of IEC 62146 is applicable to TRV capacitors used on high-voltage alternating current circuit-breakers with rated voltages above 100 kV with 50 Hz or 60 Hz.

TRV capacitors are installed phase to earth, either in parallel to the bushing on dead tank circuit-breakers, or immersed inside the circuit-breaker, or freestanding close to the circuit-breaker. Their function is to limit the transient recovery voltage (TRV) and the rate of rise of recovery voltage (RRRV) on the circuit-breaker. Capacitors in compliance with this document can be used as TRV capacitor.

This document applies to TRV capacitors falling into one or both of the following categories for:

- mounting on or close to air insulated switchgear (AIS) dead tank and live tank circuitbreakers, or

- mounting on gas insulated switchgear (GIS) circuit-breakers.

The testing for each of the above applications is in some cases different.

This document does not apply to grading capacitors installed in parallel to the chambers of the circuit-breaker, which are specified in IEC 62146-1.

This document does not apply to capacitors not directly associated with high-voltage alternating current circuit-breakers.

The object of this document is:

- to define uniform rules regarding performances, testing and rating

- to define specific safety rules

- to provide a guidance for installation and operation

The TRV capacitor is a sub-component for the circuit-breaker and is specified in accordance with the circuit-breaker specifications according to IEC 62271-1, IEC 62271-100, and if applicable to IEC 62271-203.

TRV capacitors are commonly built with composite or ceramic housings (insulators). Those insulators follow IEC 61462 or IEC 62155. Other housings can be used if they can sustain applicable type tests according to IEC 61462 and IEC 62155.