Technical Parameters Parameter Specification Product Name ABB E1N1250R1250 PR122/P‑LSIG Air Circuit Breaker Series / Family SACE Emax – E1N Protection Trip Unit PR122/P‑LSIG electronic protection Rated Current (I_n) 1250 A Rated Uninterrupted Current (I_u) 1250 A Rated Operational Voltage (U_e) Up to 690 V AC Rated Insulation Voltage (U_i) 1000 V AC Rated Impulse Withstand Voltage (U_imp) 12 kV Number of Poles 3‑pole (3P); 4‑pole version available Rated Short‑Circuit Breaking Capacity (I_cu) ~50 kA at 400 V AC Rated Short‑Time Withstand Current (I_cw) ~50 kA for 1 s; ~36 kA for 3 s Protection Functions Adjustable overload, short‑circuit (long‑time, short‑time, instantaneous), earth‑fault Auxiliary Contacts Yes, typically 4 change‑over contacts Trip Unit Adjustment Ranges Long‑time: 500–1250 A; Instantaneous: 1875–18750 A Mounting / Format Fixed or withdrawable moving part (WMP) Control & Indicators Breaker status and open/closed indication Standards Compliance IEC low‑voltage circuit breaker standards Typical Use Protection and switching in industrial/commercial electrical distribution