1.1 Function protection of circuits against short-circuit currents,protection of circuits against overload currents,switch,isolation. NB1 circuit-breakers are used in domestic installation, as well as in commercial and industry electrical distribution systems. 1.2 Selection Technical data of the network at the point considered:short-circuit current at the circuit-breaker installation point,  which must always be less than the breaking capacity of this device,network normal voltage. Tripping curves: B curve (3-5In) protection for people and big length cables in TN and IT  systems. C curve (5-10In) protection for resistive and inductive loads with low inrushcurrent. D curve(10-14In) protection for circuits which supply loads with high inrush current at the circuit closing (LV/LV transformers, breakdown lamps). 1.3 Approvals and certificates Detailed information, please refer to Certificates Table on the last page.

Rated current: 63, 80, 100(1P, 2P, 3P, 4P), 125(1P, 2P); Rated voltage: 240V ~ (1P), 415V ~ (2P, 3P, 4P); Frequency: 50Hz; Electromagnetic release type: B, C, D; Number of poles: 1P, 2P, 3P, 4P; Mechanical life: 20000 cycles; Electrical life: 6000 cycles (In≤100A); 4000 cycles (In＞100A); Rated short-circuit breaking capacity(Icn): 10000A; Short-circuit breaking capacity(Ics): 7500A; Rated impulse withstand voltage(Uimp): 4kV; CATALOG NXB-125G Miniature Circuit Breaker PDF

1.1 Certificates: CCC,CE,CB,TUV; 1.2 Standard: IEC/EN 60947-2 ,RoHS; 1.3 Rated voltage up to 1000V, Rated current up to 63A; 1.4 Protection of circuits against overload currents; 1.5 Protection of circuits against short-circuit currents; 1.6 NB1-63 DC circuit-breakers are used incommunication systems and PV   DC systems.