JNR Class ED77

The JNR Class ED77 was a Japanese AC electric locomotive operated by the Japanese National Railways and its successor the East Japan Railway Company from 1967 to 1993.
==History==
The ED77 was designed to test the capabilities of thyristor phase control in locomotives. They were intended to be used on the Tōhoku Main Line and Ban'etsu West Line.
An initial prototype, classified the Class ED93 and numbered ED93 1, was built in 1965 by Hitachi. Full-production locomotives were manufactured from 1967 to 1970; a total of fifteen locomotives were manufactured. ED93 1 was modified to full-production standards in 1968 and renumbered ED77 901 as a result. When introduced, the locomotives were based in Fukushima and used on the Tōhoku Main Line and Ban'etsu West Line to pull passenger and freight trains; plans were made for the locomotives to be used on the Senzan and Tazawako Lines but these did not come to fruition, with the ED78 introduced for use on these lines.
When the JNR was privatized and split in 1987, JR East assumed ownership of the ED77s; at this point, seven locomotives were in service. Track reinforcement of the Ban'etsu West Line made it possible for the ED75s to operate on these lines and as a result the locomotives were withdrawn from service in 1993.
No ED77s have been preserved. Three locomotives were preserved in the past but all have since been scrapped.
==Design==
The ED77s featured large box-shaped bodies with a slight rake with dual large circular headlights mounted on the top of the cars in two recesses.
==Specifications==
The ED77s used a nose suspension drive system with MT52 traction motors; the use of the nose suspension drive was due to maintenance problems involving the Quill drive, so all locomotives after the earlier EF70 would use the nose suspension drive. This however came at the cost of keeping the rated rotation speed of the traction motors low. ED77 5 was fitted with MT52A traction motors.
==Preservation==
The following Class ED77 locomotives were preserved in the past but have since been scrapped:
Number	Manufacturer	Equipment manufacturer	Date manufactured	Date retired 	Last location 	Notes
ED77 1	Hitachi 	Hitachi 	12 May 1967 	7 February 1987	Sendai General Shinkansen Depot, Sendai, Japan 	Displayed outdoors; scrapped September 2019 with a number of other preserved locomotives
ED77 2	Hitachi 	Hitachi 	May 1967 	6 February 1987	Suita Locomotive Depot, Osaka, Japan 	Stored in roundhouse; scrapped 1998 with demolition of roundhouse
ED77 8	Toshiba 	Toshiba 	1967 	7 February 1987	Railway Technology Research Institute, Tokyo, Japan	Scrapped c. 1990s
Category:JR Group trains
Category:Electric locomotives
Category:B-2-B locomotives
Category:Narrow-gauge
Category:Narrow-gauge locomotives
Category:Hitachi locomotives
Category:Mitsubishi locomotives
Category:Toshiba locomotives
Category:Japanese locomotives
Category:Scrapped electric locomotives