Dropout fuse cutout and load break type fuse cutouts are outdoor high voltage protective device with rated voltage from 3KV ~ 40.5KV.
They are connected with incoming feeder of distribution transformer or distribution line. These are primarily used to protect transformers or lines from short circuit and overloading and switching currents. The dropout fuse cutout is composed of insulator support and fuse holder, static contacts are fixed on two sides of insulator support, moving contact installed on the two ends of fuse holder, the interior of the fuse tube is arc-extinguishing tube/layer, exterior is made of phenolic compound paper tube or epoxy glass. Load break type provides stretch auxiliary contacts and arc-chute cover to switch on/off loading current.
In normal operation the fuse link is tightened to form the closed position, when fault current occurs, the fuse link melts down and electric arc produce, the arc extinguishing tube is heated and explosive gas happens. This results in high pressure inside the tube and makes tube to be disconnected from the contacts. The strength of the contact is released once the fuse elements melt down.
The cutout now is in OFF position, the operator needs to switch off the current. Use an insulated operating rod to pull, the moving contact can be pulled off.
Dropout fuse cutouts comply with GB/T15166.3，IEC282-2，ANSI /IEEE C37.41, C37.42 standards.
General Working Conditions
Operating site:outdoor
Ambient temperature：-25℃ ~ 50℃
Air humidity：≤95%
Altitude：≤2000m
Mounting angle：Approximately 15º~25 º (vertical)
