The Schneider Electric NSX400F DC 3P 400A is a 3-pole, 400A, fixed-type molded case circuit breaker (MCCB) from the Compact NSX series, specifically designed for direct current (DC) applications. It provides reliable protection for DC circuits against overloads and short circuits in demanding environments such as photovoltaic (PV) systems, battery storage, DC traction, and industrial DC power distribution.
Specifications
Parameter Specification
Product Series Compact NSX (DC Version)
Product Line NSX400F
Number of Poles 3-Pole (for DC systems, typically used in 3-wire +/- and ground configurations)
Rated Operational Current (In) 400 Amperes
Trip Unit Type DC Thermal-Magnetic (TM-D) or Electronic (Micrologic DC) depending on configuration.
Circuit Type Direct Current (DC)
Rated Operational Voltage (Ue) Up to 440V DC / 500V DC / 750V DC (specific model dependent)
Breaking Capacity (Icu) Typically 25 kA to 50 kA at rated DC voltage (e.g., 25kA @ 440V DC, 15kA @ 750V DC). Critical parameter - must verify based on specific DC voltage.
Polarity Suitable for bipolar applications (e.g., PV string protection with +/- polarity).
Standards IEC 60947-2 (Annex M for DC), UL 489B (DC Molded Case Circuit Breakers)
Connection Front or rear connection. Terminal design optimized for DC current.
Mounting Fixed mounting (panel or DIN rail adapter).
Width Approximately 158 mm (for 3-pole fixed version).
Arc Chute Design Specifically engineered for DC arc extinction, with permanent magnets or other arc control technology to ensure safe interruption.
Accessories Auxiliary contacts, shunt trip (DC coil), undervoltage release (DC), motor operator (DC) - all rated for DC operation.