ABB ST203M-B25 Industrial Relay Module With 24V DC Coil

ABB ST203M-B25 is a three-pole miniature circuit breaker (MCB) in ABB's S200M/ST-series family, providing overcurrent protection for three-phase circuits with a 25 A nominal rating. The device is cataloged as 2CDS273001R0255, with ABB cross-references ST202M-B25 and ST203M-B25, confirming its role within the same protective family and its compatibility with other S200M/ST-series devices. Configured with a B-type trip characteristic, it is intended for AC installations in industrial or commercial panels and is commonly used in distribution boards and motor control cabinets where compact, three-pole protection is needed, guarding wiring and connected equipment against overloads and short circuits. As a breaker rather than a relay module, it contains no coil and is designed to interrupt fault currents, enabling modular panel layouts that rely on ABB’s protective devices to coordinate protection across downstream circuits and integrate with ABB protective components in standard control panels.