The Schneider Electric Compact NSX400N 4P 400A is a 4-pole (3-phase + neutral), 400A molded case circuit breaker (MCCB) from the premium Compact NSX series. Featuring a standard thermal-magnetic trip unit ("N"), it provides robust and reliable overload and short-circuit protection for all live conductors in three-phase four-wire systems.
Specifications
Parameter Specification
Product Series Compact NSX
Model / Frame NSX400N
Number of Poles 4 Poles (3P + N) – All four poles are protected.
Rated Current (In) 400 Amperes
Frame Rating (Iu max) 400 A
Trip Unit Type N – Standard Thermal-Magnetic (TM-D)
Trip Unit Characteristics • Thermal Protection (Ir): Fixed at 400A (inverse-time).
• Magnetic Protection (Im): Fixed instantaneous setting, typically ~10 x In (4000A).
Breaking Capacity (Icu @ 400V) 50 kA, 70 kA, or 100 kA (Selectable via model suffix - e.g., N, H, L). The specific value is a critical selection parameter.
Rated Operational Voltage (Ue) 400/415V AC (3P+N systems), up to 690V AC.
Rated Insulation Voltage (Ui) 1000V AC
Short-Time Withstand (Icw) Typically 25-40 kA for 1s (model dependent)
Connection Front or rear connection, screw terminals suitable for busbar or large cables.
Terminal Capacity Suitable for copper/aluminum cables or busbars (typical for 2x185mm² cables or equivalent busbar).
Mounting Fixed or Plug-in (P) version available (letter after frame indicates type, e.g., F for Fixed: NSX400F N 400A).
Width (4P) ~140 mm (Thermal-Magnetic version)
Mechanical Life 20,000 operations
Electrical Life 8,000 operations at rated current
Operating Temperature -25°C to +70°C
Standards IEC 60947-2, UL 489, CCC, CE