(1) Main advantages of dropout fuse cutout
① Good selectivity. As long as the rated current of the fuse link of the upper and lower level fuse meets the requirements of 1.6:1 overcurrent selection ratio specified in the national standard and IEC standard, which means the rated current of the upper level fuse link is not less than 1.6 times of the value of the lower level, it is considered that the upper and lower level can selectively cut off the fault current;
② Good current limiting characteristics and high breaking capacity;
③ Relatively smaller size;
④ Cheaper price.
(2) Main disadvantages of dropout fuse cutout
① The fuse link must be replaced after the fault is fused;
② The protection function is single, only one section of over-current inverse time characteristic, overload, short circuit and ground fault are protected by this protection;
③ In case of one phase fusing, the three-phase motor will lead to the adverse consequences of two-phase operation. Of course, the fuse with alarm signal can be used to make up, and one phase fusing can disconnect three-phase;
④ It is impossible to realize remote control. It needs to be combined with electric knife switch and switch.