July 12, 2004

Manually Operated Omni-Rupter^® Switches Now Certified to ¾-Inch Ice-Breaking Capability.

It’s summertime outside but it’s winter inside S&C’s environmental test chamber. S&C is pleased to announce that Omni-Rupter Switches have been successfully tested and are now certified for ¾-inch ice-breaking capability.

S&C’s Switch Products Division decided to take a proactive approach to proposed changes to the National Electric Safety Code (NESC 2007) that may require overhead equipment to withstand higher ice loadings by implementing a thorough test program for manual Omni-Rupter Switches — to prove that they can withstand a full ¾-inch of ice.

Both 14.4-kV and 25-kV test switches were coated with a minimum ¾-inch of ice in the open and closed positions. Each switch operated smoothly on the first attempt . . . without the “chopping” or sticking sometimes exhibited by gang-operated switches. Smooth operation of a switch under ice is crucial for ensuring long life of the contacts and the interrupters, as well as a successful switching event even under difficult conditions. With the new ¾-inch ice-breaking capability, Omni-Rupter Switches can be applied in a wider variety of climates.

And there’s more good news. Since no modifications to the switches were needed to attain the enhanced ice-breaking performance, the ¾-inch ice-breaking capability applies retroactively to all Omni-Rupter Switches . . . including hookstick-operated switches. One caveat though: Switches in the vertical and tiered-outboard mounting configurations require the addition of ice shields to ensure ¾-inch ice-breaking capability as they have in the past for performance in icy conditions.

For more information on Omni-Rupter Switches, contact S&C.