 Rebuilding was carried out at JNR's Nagano Works.The primary aim of rebuilding was to reduce the axle load (from 15 t to 13 t) for use on the Iida Line, where the class displaced vintage (English Electric) and JNR Class ED19 (Westinghouse) locomotives, and later JNR Class EF10 locomotives.One highlight of the class's career was when ED62 15 hauled the Imperial Train on the Iida Line in 1979.