The Schneider Electric Compact NS1250-3 (modern equivalent: Compact NSX1250) is a high-current, three-pole, 1250A molded case circuit breaker (MCCB) from the legacy Compact NS series
Parameters
Parameter Value / Description
Legacy Series / Modern Equivalent Compact NS Series / Compact NSX1250 Series
Rated Current (In) 1250 A (Frame rating. Operational current is set by the installed trip unit).
Number of Poles 3
Breaking Capacity Must be specified. Available in multiple levels (e.g., N, H, L, V for NSX). Common high ratings: H1 (100 kA Icu) or L1 (150 kA Icu) at 415V.
Rated Ultimate Breaking Capacity (Icu) Depends on selected rating. Example (H1): 100 kA at 415V AC (IEC 60947-2). Example (L1): 150 kA.
Rated Operational Voltage (Ue) Up to 690 V AC
Trip Unit (Legacy NS Options) Thermal-Magnetic (TM) or Electronic (STR/STU Micrologic). The modern NSX1250 uses Micrologic electronic trip units exclusively.
Trip Unit (Modern NSX1250 Standard) Electronic Micrologic. Wide range: Micrologic 2.0A to 7.0A for protection, measurement, and communication.
Mounting Fixed or Withdrawable (Draw-out version is standard for easy maintenance and testing).
Connection Front or Rear connection (depends on kit). Designed for heavy busbar or parallel cable connections.
Standard IEC 60947-2
Typical Applications Main LV incoming circuit breaker for large buildings/factories, busbar sectionalizer/coupler, large transformer (e.g., 1000-1600kVA) secondary protection, large generator main breaker.