Specifications General Product Type: Molded Case Circuit Breaker (MCCB) Series / Family: ComPacT NSX N‑Frame Model: NSX400N with Micrologic 5.3E Number of Poles: 3 (three phases) Rated Current (In): 400 A Mounting: Fixed panel or switchboard installation Application: Protection of low‑voltage three‑phase electrical circuits Electrical Ratings Rated Operational Voltage (Ue): Suitable for low‑voltage AC systems (commonly up to ~690 V AC) Rated Frequency: 50/60 Hz Rated Insulation Voltage (Ui): Designed for standard low‑voltage distribution systems Rated Impulse Withstand Voltage (Uimp): Engineered to withstand transient overvoltages Protection & Trip Unit Trip Unit Type: Micrologic 5.3E electronic trip unit Protection Functions: L — Long‑time overload protection S — Short‑time overcurrent protection I — Instantaneous short‑circuit protection E — Enhanced selectivity and protection features Adjustability: Adjustable protection settings for long‑time, short‑time, and instantaneous trip thresholds and delays, providing coordination with upstream and downstream protective devices Breaking Capacity & Performance High Breaking Capacity: Designed to safely interrupt fault currents typical of industrial, commercial, and infrastructure low‑voltage systems Selective Coordination: Adjustable settings support selective discrimination between devices for improved system protection Mechanical & Environmental Terminal Connections: Screw or clamp type terminals for secure conductor attachment Mechanical Durability: Engineered for reliable operation and repeated switching cycles Design: Compact modular housing for efficient panelboard and switchboard integration Safety: Provides reliable electrical isolation under fault conditions