Zhejiang Zhi Duoxin Electric Co., Ltd.

Introduction 

Dropout Fuse Cutout is a kind of outdoor used high voltage protective device. To be connected with incoming feeder of distribution transformer or distribution line it mainly protect transformer or lines from short circuit and overload, and on/off loading current.

Dropout Fuse Cutout is composed of insulator supports and fuse tube,static contacts is fixed on two sides of insulator support and moving contact is installed on two ends of fuse tube. Fuse tube is composed of inside extinguishing tube ,outer phenolic compound paper tube or epoxy glass tube.Load switching fuse cutout provides enforced elastic auxiliary contacts and arc-extinguishing enclosure for switching on/off loading current. At normally working via fuse link tightened the fuse tube is fixed to form up of close position. In case system occur faults,fault current result in fuse melt immediately and take place electric arc,which let arc- extinguishing tube being heated and explode a lot of gas.This will produce high pressure and blow off the arc along with tube.    

After fuse link melt moving contact has no tightened strength again,mechanism is locked and fuse tube dropout. Cutout now is in open position.

When it needs to switch off during cut out loading. Operator shall via insulating operating bar pull the moving contact, at its beginning main contact and auxiliary static contact is contacted still.

Whiling pulling the auxiliary contact is separated between auxiliary contacts there occur electric arc and the arc will be lengthened in arc-extinguishing enclosure gap and meanwhile arc- extinguishing explode gas to blow off the arc during current passing zero.

Structural characteristics

Parallel-groove connector

Tinned for No.6 soild through 250 KC mil stranded copper oraluminum.

Recoil bar

Heavy galvanized steel(which is also used for inserts,hangers,structural bolts and nuts)

Brid proof-design insulator

Higher insulation characteristics than ANSl distribution-cutoutstandards and equal in most cases to ANSl switch and busstandards

Lower contacts

Not visible- silver-to- silver,provide dual currentpath,independent of hingepivot,Stainless-steel backup springsprevent arcing when tube rises in hinge during recoil

Upper Contacts

Silver-to-siver at both surfaces

Attachment hooks

For load buster. Heavy construction also serves to guide tubeduring closing

Fuse tube

Fiber-lined epoxy fiber glass

Toggle joint

Collapses to permit dropout when link severs

Sturdy ferrules

Pinned to top and bottom of tube for permanent alignment,Large,accessible lifting ring.

Trunnion pocket

secures tube in hinge during closing

Trunnion casting

surfaces around trunnion bear on broad hinge surfaces to keeptube in alignment during closing

Flipper

gives high-speed terminal separation，quick cable flip-out,and(in concoction with the toggle joint)reduces transmission offorces to fuse link during closing

Shape And Installation Dimensions

Technical details