Bulletin 140MT Motor Protectors

The Allen-Bradley Bulletin 140MT Motor Protectors family encompasses a broad range of motor protection circuit breakers and associated accessories designed to provide overload and short-circuit protection for AC motors in industrial applications. The catalog-number structure follows a consistent pattern: the 140MT prefix identifies the family, the next segment indicates the frame size or accessory class (e.g., -C for the compact accessory group, -KBH for a top-hat rail adapter), and trailing suffixes specify the accessory function and configuration — for example, -UXD designates an undervoltage release module rated 110V/50 Hz or 120V/60 Hz, while -UXB identifies an undervoltage release for 480V/60 Hz or 415V/50 Hz service. Side-mounted auxiliary contacts carry suffixes that encode contact configuration directly: -ASA20 (2 NO), -ASA02 (2 NC), and -ASA11 (1 NO/1 NC), each 9 mm wide. Shunt trip modules such as the -SNB (480V/415V AC) and -SNZJ (24V DC) mount on the left side of the protector body. With 168 products in the family, the 140MT line covers protection devices, spacing adapters, terminal covers, and rail-mounting hardware to support a complete motor protection assembly.