.1 Function
protection of circuits against short-circuit currents,protection of circuits against overload currents,switch,isolation.
NB1-63H 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 Â 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).