Basic Electrical Installation Work

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● They can replaced with incorrect cartridge. With larger size cartridge fuses, lugs tags are sometimes brazed the end-caps fix the fuse cartridge mechanically the carrier. The load current flows through the thermal and the Fuse element Glass ceramic body End-cap FIGURE 12. Miniature circuit breakers (BS 60898) The disadvantage all fuses that when they have operated they must be replaced. ● The declared rating accurate. Operating time inversely proportional the fault current, the bigger the fault current the quicker the fuse operates. ● not possible see the fuse element broken. ADVANTAGES CARTRIDGE FUSES ● They have mechanical moving parts. 12.Basic Electrical Installation Work 242 to the body the fuse that they not blow off when the fuse oper- ates.2. . MCB overcomes this problem since automatic switch which opens the event excessive current flowing the circuit and can closed when the circuit returns normal.2 Cartridge fuse.3 incorporates thermal and mag- netic tripping device. ● Their operation more rapid than semi-enclosed fuses. ● They are easy replace. ● They have small physical size and external arcing which permits their use plug tops and small fuse carriers. An MCB the type shown Fig. They may also filled with quartz sand absorb and extinguish the energy the arc when the car- tridge brought into operation. Cartridge fuse construction illustrated Fig. 12. ● The cartridge may shorted out wire silver foil extreme cases bad practice. DISADVANTAGES CARTRIDGE FUSES ● They are more expensive replace than fuse elements that can be re-wired. ● The element does not weaken with age