It’s been estimated that 75% of the long-term outages experienced on remote feeders of overhead distribution systems are the result of momentary faults.

Such faults can be caused by lightning strikes, animal incursions, wind-blown tree branches, or debris falling on the lines. These feeders are typically protected by fuse cutouts, which operate in response to the momentary faults, resulting in long-term outages.

Customers served from the feeders are, of course, inconvenienced and dissatisfied by the outages. Valuable revenue is lost too. And resources and time are spent, as trouble crews are dispatched to locate the faulted line section and restore service. S&C’s new single-insulator S&C Three-Shot Type XS Fuse Cutout is ideal for applications on feeders in such remote areas, as well as locales that are difficult for crews to access. The 15-kV model is rated 110 kV BIL, and is available with either a 2 kA or 6 kA asymmetrical interrupting rating. It includes three complete, sequenced-operating fuse cutouts.

The heart of the Three-Shot Type XS Fuse Cutout is its enclosed rotating current-transfer contact mechanism. When the first cutout operates, a plunger releases the mechanism, which rotates the contact and engages the next cutout.

Here’s how it works: If a fault occurs, the first cutout operates. The rotating current-transfer contact mechanism readies the second cutout, which quickly restores service to the faulted line. If the fault is still present, the second cutout operates. The rotating current-transfer contact mechanism readies the third cutout, which again quickly restores service to the faulted line. If the fault is still present, the third cutout operates, clearing the fault and opening the circuit.

The stored-energy mechanism is charged by the hookstick-operated reset-ring at the base of the cutout . . . which also indicates the active fuse. To reset the mechanism, insert a hookstick prong through the resetting-ring, and rotate the mechanism counter-clockwise.

The Three-Shot Type XS Fuse Cutout features S&C’s Multi-Wind™ Fuse Tubes, which are virtually impervious to water ingress. The fuse tubes utilize standard S&C Positrol® Fuse Links. A unique shield arrangement prevents the exhaust from fuse operation from affecting neighboring fuses. The shield is made of a durable, flexible, UV-stabilized polycarbonate material—the same material used on S&C’s distribution fuse rain caps for over 35 years. The Three-Shot Type XS Fuse Cutout works perfectly with S&C’s Loadbuster® Loadbreak Tool. Simply engage the pull-ring hook on the appropriate fuse tube, held fast by the pull-ring latch.

A firm, steady downward pull opens the cutout and trips Loadbuster, breaking the active circuit. There’s no external arc, no contact burning...just positive, convenient load switching.