The DF50 is a diesel locomotive with a lead prototype manufactured in 1957 (1957) for the smoke-free non-electrified trunk line, and expanded thereafter until 1963 (1963). The power transmission system employs an electric system in which the main motor is driven by DC power generated by a generator directly connected to a diesel engine. It is roughly divided into the 0 series equipped with the Swiss engine made by Sulzer and the 500 series equipped with the German engine made by Germany. Mainly active in Kyushu, Shikoku, San-in, Kise district.DF50 Tea commercializes the brown paint which was the paint color at the time of appearance seen until about 1965 (1965). He was a key player in promoting the smoke-free operation of JNR, and was active in pulling passenger trains composed of 35 series and 43 series of brown paint and freight trains centered on black freight cars.