3.6kV high voltage current-limiting fuse for motor protection
This product is used in indoor AC system of 50Hz, rated voltage of 3.6kV, also can be used together with other protective electric apparatus (e.g. switch, vacuum contactor, etc.) to protect high voltage motor and other electrical equipment from overloading and short-circuit.
2.Basic parameters The basic parameters of fuses are shown in table 1 Table 1
4.Shape and mounting size ¡¡ The shapes and dimensions of the fuses are shown in(Fig.4)¡¢(Fig.5)¡£
5.Selection of Fuse ¡¡ The rated current of the fuse used for direct starting is given by following formula. ¡¡ Iy=Nin ¦Ä Where£º In-------The full-load current of the motor ¡¡¡¡¡¡ ¡¡ ¦Ä--------synthetic coefficient as shown in Table 2 ¡¡¡¡¡¡ ¡¡ N--------The ration of the starting current to the full-load current, generally N=6 ¡¡¡¡¡¡¡¡ Iy-------The current value during the starting time Table 2
Starting times per hour r/h
Draw the Iy value point corresponding to the starting time on the time-current characteri£stics curve, the characteristics curve corresponding to the point or the curve at the right of the point shows the fuse to be selected. The rated current of the fuse should be greater than 1.3 times of full-load current of the motor.