The DJ1 is a two-section heavy freight locomotive that emerged from a technology transfer between Siemens and the Zhuzhou Locomotive Works (CRRC). The contract stipulated that the first three locomotives would be manufactured by Siemens in Graz and a further 17 in China with direct support from Siemens. Each locomotive consists of two identical halves, each with a driver's cab, each of which has a continuous output of 3,200 kW and can deliver up to 4,100 kW for 10 minutes. Power is being fed to three-phase motors, while the other Chinese locomotives at that time still had direct current motors.
They were intended for use on the 653 km long Datong-Qinhuangdao ("Daqin") route, which was built exclusively for the transport of coal and runs from Inner Mongolia to China's largest coal export port. To increase the tractive effort, some locomotives are each equipped with eight tonnes of additional ballast, which brings the weight of one half of the locomotive to 100 tonnes and increases the starting tractive effort from 700 to 760 kN. As early as 2006, when the more modern and more powerful HXD1 and HXD2 locomotives were introduced in larger numbers on the Daqin line, the DJ1's time of hauling coal ended and since then they have been pulling normal freight trains on other lines.
