The PV&T electrified from Merrimack, NH to Brattleboro, VT in 1912 with a fleet of 12 electric locomotives from ALCO/GE. These locomotives went into service hauling freight, allowing the retirement of classes 144 and 160, and freeing the class 172 to haul the money-making Montréal passenger and express trains. The success of these locomotives resulted in the decision to electrify the rest of the railway in 1920.
The class A (1200 hp/unit as delivered) were delivered as 2400VDC engines, but were rebuilt in 1919 to run under 3000VDC, for the PV&T decided to follow the lead of the CMStP&P with higher-voltage DC when the wires were run all the way from Portland to Montréal.
After the great depression started dying down in the late 1930s, the PV&T rebuilt the class As to 1800hp (1940) to help handle increases in traffic.
The surviving members of class A are used on the few surviving low-traffic branchlines, for industrial switching, and for work trains. They are liked by the crews and, after the 1940 rebuilding, are very good performers.