
- Powerpact™ B-frame circuit breaker accessory, LV426912, offers proven performance, flexibility and reliability. This Powerpact™ Molded Case Circuit Breaker accessory is an under voltage release. A voltage release can be used to trip the circuit breaker using a control signal. Shunt trips serve primarily for remote, emergency-off commands. Under voltage releases disconnect under low-voltage conditions. With a 0.35...0.7 x Un Threshold tripping voltage and a response time of <50 ms.