>>From courant.com
>--------------------
>A `Time Bomb' Sits Atop 30,000 Utility Poles In State
>--------------------
>
>CL&P Removing Porcelain Insulators Prone To Cracking [CL&P = Connecticut
>Light & Power]
>
>By DAVID OWENS
>Courant Staff Writer
>
>September 13, 2005
>
>The fire that incinerated four cars and a Dunkin' Donuts restaurant May 7
>began with a tiny crack in a porcelain insulator high atop a utility pole
>along Route 4 in Farmington.
>
>Through that crack flowed 23,000 volts of electricity that burned through a
>wooden cross arm. The wire carrying those 23,000 volts then fell to the
>ground, touching off the fire.
>
>A cool-headed Dunkin' Donuts manager locked the restaurant's front door and
>herded customers and employees out the back. Police and firefighters say it
>was a miracle no one was killed or injured.
>
>At the time, it appeared to be one of those freak accidents that just occurs
>from time to time.
>
>It wasn't.
>
>The insulator that failed was attached to a protective device called a
>"cutout" made by A.B. Chance, a division of Hubbell Inc., in Orange, Conn.
>
>There are tens of thousands of cutouts on utility systems. Cutouts halt the
>flow of electricity if there is a surge, protecting transformers and other
>electric equipment the same way circuit breakers protect a home.
>
>The Farmington fire was an extreme example of what can happen when a cutout
>fails. But older cutouts - especially those made by Chance - fail more
>frequently than other types, according to a utility company study, persuading
>utility companies around the Northeast, including CL&P, to replace them.
>Unions representing lineman whose safety depends upon reliable equipment say
>replacements are not going fast enough. They fear that the older
>porcelain-insulated cutouts jeopardize public safety.
>
>"They're basically a time bomb that should be aggressively pursued," said John
>Unikas of Local 420 of the International Brotherhood of Electrical Workers,
>which represents many CL&P line workers.
>
>Unikas said the union complained to CL&P about A.B. Chance porcelain cutouts.
>The union also complained to the U.S. Occupational Safety and Health
>Administration about an April 20, 2004, incident in Goshen, where a Chance
>ceramic cutout failed. In that incident, like in Farmington, a cross arm
>burned, causing a high voltage wire to drop, in this case, onto the wire
>carrying electricity to a house. It damaged the home's electrical system and
>some appliances.
>
>Reports of problems with A.B. Chance cutouts seem to be confined to northern
>climates, and utility officials suspect the freeze-thaw cycle is to blame.
>
>A spokesman for Hubbell Inc. said Monday he was not aware of the Farmington
>fire, but said the company would investigate.
>
>The spokesman did say trouble with porcelain insulators is an industry problem
>and not confined to A.B. Chance products. Porcelain insulators are susceptible
>to cracking because of fluctuations in temperature in cold northern states,
>Thomas R. Conlin, the company's vice president for public affairs, said.
>
>Utilities in the South do not report such problems, he said.
>
>Porcelain is a very durable material, but the smallest crack can create a
>problem, Conlin said. "It freezes and then you know what happens," he said.
>
>Utilities in the North are switching to a new kind of cutout that uses a
>polymer material as the insulator, Conlin and utility company officials said.
>
>Conlin attributed the singling out of A.B. Chance cutouts by some utilities
>and others to the company's market share. "The odds are when one fails, since
>A.B. Chance sells a larger number of these than anyone else, it's likely it
>will be an A.B. Chance cutout," Conlin said.
>
>CL&P says the remaining 30,000-plus A.B. Chance ceramic cutouts on its system
>are safe. Still, the company is removing them at a pace of about 4,000 a year.
>An extra $500,000 was allocated to that effort in 2005 as part of a settlement
>of a federal OSHA complaint brought by the union. The removal program is
>expected to take years, added CL&P spokeswoman Mary Ingarra. "They're not
>living up to their [life] expectancy" of about 40 years, she said.
>
>NU is not alone in reporting trouble with Chance cutouts.
>
>The Washington Electric Co-operative in Vermont has termed A.B. Chance
>porcelain cutouts "lemons" in newsletters sent to its members. And co-op
>officials in recent years reported failures of A.B. Chance ceramic cutouts as
>the second leading cause of power outages on its system. Severe weather was
>No. 1.
>
>Pennsylvania Power & Light, which serves central and northeastern
>Pennsylvania, is removing A.B. Chance porcelain cutouts from its distribution
>system.
>
>Dan Weston, engineering and operations director for the Vermont co-op, said he
>issued his linemen binoculars so that they can carefully inspect A.B. Chance
>porcelain cutouts before they begin climbing a pole. "By jiggling the pole,
>this thing can physically break in half," Weston said. "Linemen start to climb
>a pole and this thing will fall apart and you can have a ball of fire up
>there."
>
>Not all cutout failures spark fires. Most often, the result is a localized
>power outage or downed wires. But reliability problems with the A.B. Chance
>porcelain cutouts have cost utilities money as they buy new cutouts to replace
>the failed devices and pay line crews to do the work. Weston estimates
>replacing a faulty A.B. Chance porcelain cutout costs his company $300.
>
>Northeast Utilities - which includes CL&P, Western Massachusetts Electric and
>Public Service of New Hampshire - determined in May 2001 that the typical
>failure rate of porcelain cutouts from 1988 to 2001 was 0.12 percent,
>according to a letter to the Hartford OSHA office from two CL&P managers.
>
>The company study attributed the failure of the porcelain cutouts to cracks in
>cemented connections to metal hardware as well as cracks in the glazing on the
>porcelain. The cracks allow moisture to get into the porcelain or the cemented
>connections. During the freeze-thaw cycle, the cracks widen. The company
>estimated it would have 500 porcelain cutout failures a year.
>
>"The A.B. Chance porcelain cutouts have experienced a slightly higher failure
>rate than other brands," the CL&P letter reads. "Northeast Utilities stopped
>purchasing A.B. Chance cutouts in February of 2001. Approximately 50,000 A.B.
>Chance devices were in service in 2003. Action has been taken to ensure ...
>the replacement of existing A.B. Chance porcelain cutouts."
>
>NU replaced the Chance cutouts with porcelain cutouts manufactured by S&C
>Electric Co., and reliability of those devices has "been consistently high,"
>the letter reads. NU is now installing cutouts with polymer insulators.
>
>The Farmington fire has left Farmington Town Council Chairman Bruce Chudwick
>wanting to know more about the incident. However, the state agency charged
>with regulating utilities has opted not to take a closer look at what happened
>in Farmington on May 7.
>
>"We don't know what caused this, whether there was a storm the day before that
>could have cracked something," said Beryl Lyons, a state Department of Public
>Utility Control spokeswoman. "Because there were no fatalities or injuries, we
>are not obligated to do an investigation."
>
>Chudwick said he was surprised by that response. "We have to wait for someone
>to get killed or injured before they look at this?" Chudwick said. "This seems
>like a serious enough incident that it should warrant investigation by DPUC."
>Copyright 2005, Hartford Courant
>
>
>--------------------
>Visit www.courant.com for Connecticut news updates, sports stories,
>entertainment listings and classifieds.
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