NSTAR: Substation Issue Caused Power Outage to 19,000 Saturday Morning

NSTAR says a "lightning arrestor failed at its Speen Street substation" causing 19,000 customers in Framingham and Natick to be without power early Saturday morning.

A lightning arrestor is used in a substation like a surge protector is in your home. A lightning arrestor is a protective device that limits surge voltages due to a lightning strike or an equipment fault.

Customers were without power for as short of time as 20 minutes to about 3 hours, according to NSTAR.

The first reports of the power outage came about 12:45 a.m. Saturday. Most of Route 9 in both communities was without power.

AMC Theatre also lost power, according to Framingham Patch readers, many of whom texted Patch.