What is transient recovery voltage and how does it affect circuit breaker selection?

Transient recovery voltage (TRV) is the voltage across circuit breaker contacts after current interruption, determined by system configuration and fault location. TRV can reach 2-3 times normal voltage with high frequency oscillations. Breakers must withstand this voltage while contacts are still close together and arc may restrike. TRV rate-of-rise is critical - breakers have specific TRV capability curves. Capacitor switching, reactor switching, and short-line faults produce severe TRV. Analysis uses electromagnetic transient programs (EMTP).