Parameter Category Specification General • Type Indoor, Vacuum, Fixed or Draw-out (depends on panel design) • Standard IEC 62271-100, ANSI C37.06 • Rated Voltage (Ur) 12 kV • Rated Frequency 50 / 60 Hz Insulation Level • Power-Frequency Withstand (Ud) 12 kV (1 min) • Lightning Impulse Withstand (Up) Typically 42 kV or 75 kV (Standard impulse withstand for 12kV class is 75 kV, but 1212 suggests a lower insulation level; this must be verified. It often corresponds to a 28 kV or 42 kV Up). Critical to confirm with actual datasheet. Current Ratings • Rated Normal Current (Ir) Common frame sizes: 630A, 1250A, 1600A, 2000A, 2500A, 3150A. The specific value is not defined in 1212-31 and must be specified separately (e.g., VD4M 1212-31 1250A). • Rated Short-Circuit Breaking Current (Isc) 31.5 kA (RMS, symmetrical) • Rated Short-Time Withstand Current (Ik) 31.5 kA for 3 seconds (typically) • Rated Peak Withstand Current (Ip) 80 kA (2.55 x Isc) Switching Performance • Rated Breaking Capacity Full Isc at Ur. Suitable for transformer, cable, and motor switching. • Mechanical Endurance ≥ 20,000 operations (M2 class) • Electrical Endurance ≥ 10,000 operations at full Ir (E2 class) Operating Mechanism (M) • Type Spring-operated, stored energy. • Charging Electric Motor for automatic spring recharging after each operation. • Closing Time ~60 – 80 ms • Opening Time ~40 – 60 ms Control & Auxiliaries • Standard Releases Interfaces with external protection relay. Equipped with Shunt Trip (MX) and Undervoltage Release (MN) as common options. • Auxiliary Contacts Multiple changeover contacts for signaling breaker status. • Control Voltage Common DC voltages: 48V, 110V, 220V DC. Must be specified. Vacuum Interrupter Axial or radial magnetic field design for long contact life and low chopping current. Dimensions & Weight Varies significantly with current rating. A 1250A fixed version approx.: • Width: ~ 400-500 mm • Height: ~ 600-700 mm • Depth: ~ 700-800 mm • Weight: ~ 150 – 250 kg