– Isolating knives:
+ The primary task of a isolating knife is to create an insulating gap visible between live parts and a circuit breaker. Isolation knife only for switching when there is no current;
+ Isolation knives are made with different voltage levels, 1-phase or 3-phase, for indoor and outdoor installations;
+ Isolation knives are selected with rated conditions: current and pressure with dynamic and thermal stability conditions.
Fuses are electrical appliances that protect the circuit when short circuiting. Cutting time of fuse depends on the material of the fuse. The chi bridge is a simple, low-cost protective device, but the sensitivity is only effective when the current is many times larger than the norm (mainly short-circuit current).