Technical Parameters
Parameter Specification
Product Name ABB PR122/P‑LSIG 1250 A Air Circuit Breaker
Protection Trip Unit PR122/P‑LSIG (electronic)
Rated Current (Iₙ) 1250 A
Rated Operational Voltage (Uₑ) Up to 690 V AC
Rated Uninterrupted Current (Iᵤ) 1250 A
Number of Poles 3‑pole (standard configuration)
Rated Insulation Voltage (Uᵢ) 1000 V AC
Rated Impulse Withstand Voltage (Uₚₘₚ) 12 kV
Short‑Circuit Breaking Capacity (Icu) Approx. 65 kA at 400–415 V AC
Short‑Time Withstand Current (Icw) ~55 kA for 1 s
Overload Release Setting Range 500–1250 A
Short‑Time Delay Setting 750 A
Instantaneous Release Range 1875–18750 A
Protection Functions Adjustable overload (L), short‑time (S), instantaneous (I), and earth‑fault (G)
Auxiliary Contacts Yes (typically 4 change‑over)
Mounting Types Fixed frame or withdrawable moving part (model dependent)
Control & Indicators Breaker position and trip indication
Standards Compliance IEC low‑voltage circuit breaker standards
Typical Use Protection and switching in industrial/commercial power distribution
The ABB PR122/P‑LSIG 1250 A is a low‑voltage air circuit breaker (ACB) from ABB’s Emax series, designed for use in industrial and commercial electrical distribution systems. It is rated for a continuous current of 1250 A and features the PR122/P‑LSIG electronic protection trip unit, which offers adjustable long‑time (overload), short‑time, instantaneous, and earth‑fault protection.