As part of the British Transport Commission's Modernisation Plan of 1955, twenty-four electric locomotives were built in 1958 for the Kent Coast main lines.

In some yards (notably Hither Green, South East London and Snowdown colliery near Dover) overhead wiring energised to 650V DC was used.

This overhead collection method was only employed where it was deemed too dangerous to have an electrified third rail, with staff constantly at ground level reaching between vehicles to couple and uncouple trains.

The overhead system utilised tram-style contact wires and pantographs – it was not necessary to collect traction current at speed and these provided a cost saving.

The danger of electrocution of staff at track level was the entire tenet behind the Southern Region/Railway adopting the high-level brake pipes and control jumpers (nicknamed "bagpipes") that are so distinctive of SR stock.

As more areas of the Eastern section were given over to multiple unit (EMU) operation, however, the class found itself ousted almost completely from passenger work.

Much freight is moved overnight, when congestion on the busy commuter corridors is low; but this is also the time when engineering possessions of the track take place, the power being switched off to whole districts while this happens.

The flywheel booster allowed the locomotives to make short movements "off the juice" – in yards and depots for example – but not for significant distances.

Two were awaiting repair at Ashford due to failures and the end finally came on the last day of 1977 when all 14 members were withdrawn en bloc as a result of motive power rationalisation.

The one preserved example (erstwhile 71 001) was saved by the National Railway Museum in York (currently on display at NRM Shildon) and has been restored as E5001.