In the steam and early diesel era a system of head codes were used to denote the trains make up and purpose using either discs or lamps, except on the Southern Railway / Region where the discs and lamps were officially known as Engine Head Signals and denoted the route of the train.
All engines, unless otherwise specified in the relevant Sectional Appendix, must carry discs (daytime only) or head lamps (lit at at night) as shown below depending on the classification of the train. Trains will be signalled and take precedence in accordance with the headcode.It was the responsibility of the Driver to ensure the proper head code is shown, the Guard will also instruct the engine driver to alter the discs or headlamps when any change in classification of the train is necessary. If a train is worked by two engines attached at the front, the second engine (inside engine), must not carry and discs or lamps.
Head codes D, E and F are for 'partially fitted' or 'unfitted' trains. Fitted refers to the wagons or stock having brakes under the control of the driver.
All trains should show a red lamp at the rear of the last vehicle.
Steam locomotive Lamps are available from a number of suppliers, such as Bachmann here or Springside here.











