The Westinghouse DA75 3000A air circuit breaker is a heavy‑duty low‑voltage protection device originally manufactured by Westinghouse Electric & Manufacturing Company for industrial power distribution systems. Built on the rugged DA‑75 frame, this breaker is designed to handle high continuous current demands up to 3000 A, making it suitable for service entrance, main incoming feeders, large motor loads, and heavy industrial switchgear installations operating typically at 480–600 V AC.

Featuring a 3‑pole configuration, the Westinghouse DA75 series combines reliable interruption capability with durable mechanical construction to provide dependable protection in environments where electrical reliability and safety are paramount. Many units were originally supplied as draw‑out breakers, allowing easy removal or insertion into switchgear racks for inspection, maintenance, or replacement without disturbing the main bus connections.

The Westinghouse DA75 frame was historically offered in both manual and electrically operated versions, and many breakers have been retrofitted with modern electronic protection systems with LSIG (Long‑time, Short‑time, Instantaneous, Ground‑fault) trip functions for improved coordination and selectivity with downstream protective devices. The heavy copper contact assemblies and robust arc interruption components ensure long service life even with frequent switching operations typical in industrial applications.

Although no longer produced by Westinghouse, these breakers remain in service in many legacy electrical systems and are frequently refurbished, tested, and reconditioned by specialized electrical equipment suppliers. Their proven performance and compatibility with retrofit protection units make them a practical choice for extending the life of existing switchgear infrastructure

Westinghouse DA75 3000A Air Circuit Breaker, Line and load terminal connectors, Manual and/or electrical operator mechanism, Arc chutes and interrupters, Control wiring harness, Racking mechanism or mounting cradle (if applicable), Test or calibration certificate (if provided), User manual and installation guide, Safety and compliance documentation, Manufacturer warranty card, Original Westinghouse packaging