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Watertown company helps keep power on

Pat Greenhouse/Globe Staff

WATERTOWN — When you flip the switch, the lights come on. Doble Engineering Co. of Watertown is a big reason why.

Doble helps utilities assure the reliability of their electrical distribution and transmission systems — in other words, the power comes on when you need it — by providing technology, analysis, and expertise that companies use to test the transformers, generators, and circuit breakers that deliver electricity. Founded nearly a century ago, Doble counts 90 percent of the utilities in North America as clients, including virtually 100 percent of utilities in New England.

Both of the region’s largest investor-owned utilities, National Grid and Northeast Utilities, the parent of NStar and Western Massachusetts Electric Co., are Doble customers.


“Any utility that you mention, for the most part, uses Doble,” the company’s president, David B. Zabetakis, said.

The company was founded in 1920 by Frank Currier Doble, a Tufts University graduate who paid for the electrical engineering degree he earned in 1911 by wiring the college for telephones.

From 1925 to 1947, Doble ran his firm from offices in the American Radio and Research Corp. building at the Medford campus. There he met with utility clients, demonstrating the different diagnostic test equipment his company was inventing for the young power industry.

Doble’s first product breakthrough came in 1929, when it introduced its Portable Insulation Test Set. The set was created following a challenge issued by General Electric, which had problems with bushings — the insulated device that connects high-voltage power lines to circuit breakers and transformers — and needed a way to test them before they failed.

Five years later, Doble followed with another innovation, bringing together customers and the company’s scientists and engineers to exchange ideas and the findings from tests run with Doble equipment.

Among other services, Doble Engineering runs tests at its Watertown labs to help utilities improve certain materials, such as copper windings, and equipment, such as insulators (above).
Among other services, Doble Engineering runs tests at its Watertown labs to help utilities improve certain materials, such as copper windings, and equipment, such as insulators (above).Pat Greenhouse/Globe Staff

Doble began collecting information from those sessions to create new products and improve old ones. It also shares the data with clients wanting to know how their equipment has performed over time.


Those relationships, combined with a growing database and continued innovation, helped Doble beat its competition and become the dominant player in the industry.

This week, Doble is holding its 81st conference, an event that runs through Friday.

“We currently hold 32 million points of test data on over 1 million different electric apparatus,” Zabetakis said.

While many of Doble’s products are used in the field by utility employees, the firm maintains an extensive set of labs at its Walnut Street offices in Watertown.

Here, scientists and engineers conduct thousands of tests for clients each year, helping utilities build better, stronger, more durable equipment that will stand up to extreme conditions.

Leah Simmons runs the lab that tests high voltage gear, spending her days zapping various components with man-made lightning to analyze how they hold up to large jolts of electricity.

Some researchers examine burnt out transformers and other damaged equipment to learn why they failed. Others test the various components found in utility equipment — including copper wire, paper, and mineral oil.

For instance, paper-wrapped copper is submerged in oil — often used as an insulating material or cooling agent— to observe the chemical reaction and how that might affect a piece of equipment’s life span.

The most important test, however, involves mineral oil used as an insulator. Workers analyze syringes filled with the oil for dissolved gases that — if present — can serve as a warning sign of problems with a piece of equipment or reveal what went wrong after a failure.


After a connection between a power line and a transformer sparked a fire at an NStar substation in the Back Bay in 2012, the Boston utility asked Doble to perform tests on the oil used at the station before it was brought back online. Doble ultimately gave the all-clear.

“The transformer had been exposed to heat and fire, so before we felt comfortable putting it online, we wanted to make sure there was no internal damage,” said Craig Hallstrom, president of Northeast Utilities’s subsidiaries, NStar and Western Massachusetts Electric. “Their tools allow you to kind of profile the equipment, make sure everything is ready to go when called upon.”

Doble also works closely with its customers to develop and improve its testing equipment. For example, it uses one of National Grid’s substations to try out is latest technology. Doble also surveys field workers and other employees who use the equipment to gather data on how effectively it performs.

“They ask our feedback because the end user is going to be our field workers,” said John Gavin, director of substation engineering at National Grid.

Doble was acquired by ESCO Technologies Inc. of St. Louis in 2007. Doble has offices around the globe, including in South Africa, China, Scotland, and Dubai.

But its headquarters, located in the building that once housed the William Underwood Co., known for canning deviled ham, remain in Massachusetts, where about 180 of Doble’s 400 worldwide employees work.


Zabetakis, Doble’s president, keeps a jar of M&Ms on the coffee table in his office as an enticement for workers to stop by. Twice a day he walks the labs, a 1.1 mile loop, exchanging hellos with those who have time and checking in on the numerous tests that help keep the utility industry safe and the electricity flow-ing.

“All this happens right here in Massachusetts,” Zabetakis said, even though “no one [really] knows that Doble exists.”

Erin Ailworth can be reached at erin.ailworth@globe.com. Follow her on Twitter @ailworth.