Between 1983 and 1984, the South African Railways placed sixty Class 7E3, Series 1 electric locomotives with a Co-Co wheel arrangement in mainline service.

[1] On the Class 7E3, Series 1, control of traction and rheostatic braking is by stepless solid-state electronics.

The electrical equipment was designed for high power factor operation, obtained by the switching in of power-factor correction capacitors.

[4] In the period from the early 1990s until 2007, various modifications to improve downhill braking capacity were done to the Coalink line's Hitachi-designed locomotives.

[2] By October 2007 all these locomotives were fully upgraded and standardised in respect of their rheostat flat topping and EPROM software.

The Class 7E3, Series 1 locomotives all served on the 25 kV AC Coalink line from Ermelo via Vryheid to the Richards Bay Coal Terminal.

[2][4] All the Class 7E3, Series 1 locomotives were delivered in the SAR red oxide livery with signal red buffer beams and cowcatchers, yellow whiskers and with the number plates on the sides mounted on three-stripe yellow wings.

In the 1990s some of them were repainted in the Spoornet orange livery with a yellow and blue chevron pattern on the buffer beams and cowcatchers.

In the late 1990s many were repainted in the Spoornet blue livery with either solid or outline numbers on the long hood sides.