Westinghouse 400Q Circuit Breaker Rating Plug

The Westinghouse 400Q Rating Plug is an adjustable-trip configuration accessory for AQB circuit breakers used in industrial power distribution systems. It is installed in switchgear assemblies and circuit breaker panels to set and control the trip current, providing overcurrent protection for continuous operation. The component carries Manufacturer Part Number 400Q, Brand Westinghouse, Product Type Rating Plug, Compatible Equipment AQB Circuit Breakers, and Installation Type Breaker Assembly Mount. Designed for simple, direct integration, it mounts to the breaker assembly during maintenance or upgrades. The rating plug supports trip-current configuration and is intended for industrial electrical installations. Common applications include industrial power distribution systems, switchgear, and distribution panels where precise current settings are required. Maintenance teams and system integrators use it for replacement servicing, breaker maintenance, and electrical protection system upgrades. Common replacements include the Westinghouse 600Q Rating Plug, Siemens WLTS Rating Plug, and Eaton Digitrip Rating Plug.