In September 1968, along with the AC electrification of all lines on the Tohoku Main Line, the section between Okuha Main Line and Fukushima-Yonezawa's Itaya Pass was switched from DC electrification to AC, and the Yonezawa-Hamae Chitose section was also AC electrified at the same time, and Sendai. -The Senzan Line between Hazen Chitose has also become AC electrified, and the ED78 for the sub-trunk line gradient line section has appeared.
The ED78 has specifications that match the line standards of the Senzan Line so that it can be used on both the Senzan Line and the Ou Main Line, and although it is a D type, it is a large body equipped with an intermediate bogie due to the increase in equipment dedicated to graded lines.
Corresponding to the steep slopes of the Itaya Pass on the Ou Main Line and the Sakunami Tunnel on the Senzan Line, it was the first AC electric locomotive to be controlled by a thyristor along with its brother EF71, and was equipped with a power regenerative brake.
- Reproduce the figure that was active in the JNR era with the primary form as a prototype
- Expresses the thick front step that extends to the side, which is a feature of the ED78 primary type
- Reproduce the front window equipped with defroster (anti-fog), protector mounting bolt to prevent damage to the front window due to tsurara, front ventilation port, inner fit type tail light
- The guideman hand pickpocket / release lever is reproduced with separate parts
- Reproduce the jumper plug around the lively skirt, which is a feature of the double-heading specification, with the attached separate parts
- Stable running is possible with a power unit equipped with a flywheel.
- Arnold coupler standard equipment. Replacement knuckle coupler included
- The license plate reproduces the cutout character number. Can be installed by selecting from "3", "4", "6", and "9". Maker's plate is "Hitachi" printed
- Supports quick head mark. "Akebono" and "Rapid antelope" head marks are included
- Accessories: Selectable license plate, jumper plug, replacement knuckle coupler, quick head mark "Akebono" "Rapid Kamoshika"