Ditchlight Flasher Unit for diesel electric locomotives

From RailCorp's Rolling Stock Engineering Standards:

  • Visibility lights should alternatively flash on and off when the horn is sounded
  • If visibility lights are fitted with a flashing feature, the rate of alternate flashing shall be at least 40 flashes per minut and shall be at most 180 flashes per minute
  • If visibility lights are fitted with a flashing feature, the flashing shall continue for a period of at least fifteen seconds after the horn has been sounded

The flasher unit was designed to comply with these requirements and is programmable for any frequency of flashing, as well as the duration after the horn application. It will be installed in the new 8420 diesel electric locomotive, built in Junee.

The unit can be supplied for the following control voltages: 24, 74 and 110VDC. As the circuit for the ditch lights is separated by relays from the control circuit, the lamp voltage can be any of the above.

For a single cab locomotive, the ditch lights at both ends can be controlled by the Flasher Unit. For a dual cab loco, a Flasher Unit might be required at each end.

Max load (each lamp): 150W.

Example of how the Flasher Unit is connected on the 8420 loco.