10,000 Franklin County customers briefly without power after Thursday night substation outage

If you were one of the 10,000 Eversource customers in Franklin County who were left in the dark Thursday night or who woke to find the clock on your stove reset Friday morning, a company spokesperson said a tripped transmission relay was to blame.

At 11 p.m. Thursday night, the Cumberland substation in Greenfield lost power, which caused an outage for 10,000 customers, with dozens of folks from Greenfield to Deerfield reporting power outages on social media.

Priscilla Ress, a spokesperson for Eversource, said the outage was the result of transmission line relays tripping at the substation. She added the company restored power to more than 6,000 customers in less than a minute using remote-switching capabilities, while the remaining 4,000 customers had power about an hour after the lights went out.

“The outage was caused when the transmission relay lines tripped. Relays are devices that protect transmission lines and also control power flow. When the relay to the substation tripped, it shut down the flow of power,” Ress explained in an email. “We are still investigating what caused the relays to open.”

As of noon on Friday, electricity has been restored to all of Franklin County, according to Eversource’s outage map, which can be accessed at bit.ly/4h4CPzV.

Chris Larabee can be reached at clarabee@recorder.com.