ABB ST203M-C25 Electromechanical Time Delay Relay

ABB ST203M-C25 is a three-pole miniature circuit breaker (MCB) with a C-curve trip characteristic and a 25 A rating. This UL 1077-listed device protects 3‑phase circuits in distribution panels and control cabinets from overloads and short-circuit faults, interrupting current when the threshold is exceeded to safeguard wiring and connected equipment. Belonging to ABB’s ST/S203M family of molded‑case breakers, the ST203M-C25 is designed for industrial and commercial 3‑phase installations and provides compact, reliable overcurrent protection for feeders and branch circuits. With a 25 A nominal rating, it accommodates loads up to 25 amperes under normal operation, while the C‑curve profile offers moderate inrush tolerance suitable for general-purpose loads such as motors and equipment drives. The breaker is intended for use in compatible ABB panel systems and aligns with standard mounting and termination practices for 3‑phase distribution schemes.