Infrared used to spot trouble before it starts

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— Crews from Yampa Valley Electric Association may have avoided four future power outages in downtown Steamboat Springs last week thanks to an infrared scanner on loan from the federal government.

Eldon "Bud" Stanley, operations manager for YVEA, said his staff spotted four hot spots on downtown "fuse cut-outs" and "insulating links" and promptly replaced the weakening equipment before it could cause a power outage like the one that hit downtown during the dinner hour March 29.

Hot spots are a sign that electrical equipment near transformers is beginning to fatigue and is in danger of failing. Without an infrared detector, YVEA crews have no way to detect the hot spots before they caused a failure, Stanley said. Thanks to the loan of the portable infrared device from the Western Area Power Association, Stanley said he thinks his crews have begun to get on top of a spate of power outages that have impacted electrical service here since the first of the year. YVEA has used infrared scanners before, but not in Old Town Steamboat.

"We've never done it downtown, and it caught us," Stanley said. "We never thought we had a problem."

The worst power outages of the new year came within a span of four days in January. About 1,400 customers went without power for several hours on Jan. 7 and another 1,800 customers experienced similar outages Jan. 10. Those incidents were traced to faults in underground lines.

All but one section of underground line related to a January outage that affected the ski area base has been replaced, Stanley said. The remaining section runs under the Headwall Ski Trail and is scheduled for replacement this spring.

The more recent outages in downtown have been related to failed fuse cut-outs and insulating links. Within the city, there are thousands of fuse cut-outs ranging in age from 5 to 15 years old, Stanley said. The cut-outs, which look like ceramic insulators about 16 inches long, are mounted on poles outside transformers. Their role is to protect the transformer.

YVEA has observed that a particular brand of fuse cut-out isn't delivering the longevity it should. A three-man crew is swapping that equipment for a different brand, and the work in downtown Steamboat should be completed next week.

A failed fused cut-out was partly to blame for the March 30 incident, Stanley said. A second back-up fuse inside the transformer should have prevented it from taking down power in the entire downtown, but it failed also.

When the internal fuse failed, 12,470 volts of electrical current caused "a humongous arc," inside the transformer, Stanley said.

The infrared scanner resembles a beefy hand-held video camera. The operator wears a power pack on a belt. The picture the operator sees through the viewfinder would disappoint most home video enthusiasts; not only is it in black and white, the image appears like a negative. Anything that appears dark is actually cold, and anything that is intensely white is a source of heat.

The equipment works best on a cool spring evening, when the relative heat of a weakening electrical component stands out the most from its surroundings.

Stanley aimed the scanner at an aluminum metal part called an insulating link last week and it showed up as a white dot on the screen, indicating a potential problem.

The scanner operator can see a readout of the temperature of objects in the center of its viewfinder. But to get a precise temperature reading that gives a true indication of how severe the problem is, the image is downloaded to a computer screen.

Stanley said the infrared technology isn't new to the utility industry, but until recently it was far more cumbersome to use. He can recall using a heavy scanner that required he be tethered to a cart bearing a heavy tank of liquid nitrogen.

The scanner on loan from WAPA costs about $30,000. Most of the work in Steamboat is being done by a new employee, sub-station technician Paul Turner, who is in the midst of moving here from Missouri.


There are literally hundreds of thousands of insulating links in the YVEA system Stanley said. They are a modest piece of aluminum hardware that binds two power lines together. As power flows through them, they are continuously stressed by expansion and contraction due to thermal cycling. Eventually, they can fail altogether.

Monitoring all of the insulating links is a big chore. But with annual checks by infrared scanner, Stanley believes YVEA will get its power outages under control.

"Nobody hates those outages more than we do," Stanley said.


-- To reach Tom Ross call 871-4210, or e-mail: tomross@amigo.net

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