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 (as denoted by /3) Breaking Capacity Must be specified. Available in multiple levels (e.g., N, H, L for NSX). Common high rating: H1 (100 kA Icu at 415V). Rated Ultimate Breaking Capacity (Icu) Depends on selected rating. Example (H1): 100 kA at 415V AC (IEC 60947-2). 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 for easier maintenance). Connection Front or Rear connection (depends on kit). Designed for busbar or large cable lug connections. Standards IEC 60947-2 Typical Applications Main LV incoming feeder, busbar sectionalizer, large transformer secondary protection, large motor or capacitor bank feeders.