SPD Technologies AQB-LF250 Naval Circuit Breaker

The AQB-LF250 Naval Circuit Breaker is a three-pole, molded-case breaker for shipboard electrical power distribution, rated up to 250 A and 500 V AC with a 100 kA interrupting capacity. It supports a removable trip unit with long-time and instantaneous trip functions and can be configured with optional undervoltage release, shunt trip, and auxiliary switch; some variants are described as fused with overcurrent/short-circuit protection and fuses. Identified by NSN 5925-01-185-5155, this breaker is part of the naval AQB family specified for shipboard use, with mounting and wiring options aligned to standard block assemblies and common hardware such as 1/4-20 mounting screws.