Siemens CQDST120 Shunt Trip

Siemens CQDST120 Shunt Trip is a remote-control trip accessory for Sentron molded‑case breakers in the CQD, CQD6, BQD, NGG, and NGB families, designed to discharge the protected circuit immediately when a 120 V control signal is received. The coil operates at 120 VAC and draws about 0.09 A, enabling integration with low-current supervisory circuits or safety relays, and it is available as the standalone CQDST120 or as the CQDST120AAS, which includes an auxiliary signaling switch. The device’s form factor is engineered to fit standard CQD/BQD frames, with typical installation dimensions around 4.7 inches long, 3.4 inches wide, and 2.1 inches high, ensuring straightforward retrofits in existing panels. Typical applications include remote tripping in building distribution panels and safety-critical systems where a dedicated shunt-trip channel is required for rapid disconnection on fault or safety events.