Indian Railways sought support from ABB in Switzerland to develop a modern three-phase locomotive. The first six locomotives were built directly by ABB and production was gradually switched to purely Indian companies. The designation WAG-9 stands for broad gauge, AC, goods and generation 9. The variants are the WAG-9H with additional ballast, the WAG-9i with IGBT converters, the WAG-9Hi as a combination of the H and i, the WAG-9HC with vacuum brakes and the higher powered WAG-9HH. The WAP-7 was developed parallel to the WAG-9. By early 2023, 3,899 machines had already been completed, while production continued at several plants. 