Bell code
Bell codes, buzzer codes or Communication Signal Appliance codes entail a series of bells or buzzers used on passenger trains for communication between the driver and guard.
Great Britain and India
| Signal | Meaning in Great Britain[1] | Meaning in India[2] | 
|---|---|---|
| 1 | Stop | Stop train | 
| 1—1 | Zone of speed restriction over, resume prescribed speed | |
| 1—2 | Close doors | |
| 2 | Ready to start | Start train | 
| 2—2 | Do not open doors | Passing automatic signal at 'on' | 
| 3 | Set Back | Guard required by driver | 
| 3—1 | Lock central door locking | |
| 3—2—1 | Testing doors | |
| 3—3 | Guard required by driver, or guard or driver to speak on the telephone | Guard's warning when the motorman exceeds the speed prescribed | 
| 3—3—1 | Release central door locking | |
| 4 | Slow down | Protect train in rear | 
| 5 | Driver/Guard leaving the train | |
| 6 | Draw forward | |
| 9 | Police assistance required | 
All codes, except 3—2—1, must be acknowledged by repeating the code received.
Japan
In Japan, these are known as In-Car Communication Signals (Japanese: 車内連絡合図, romanized: Shanai renraku aizu). Each code must be acknowledged by the receiver. Examples of common railway bell codes are:
| Signal | Meaning | 
|---|---|
| • • — • • | Buzzer Test | 
| • | Buzzer is OK | 
| — | Am I clear to proceed? | 
| • • • | The indicator light does not illuminate | 
| • • | Prepare to stop at the next station | 
| • | Acknowledgement for • • | 
| • • — | Please correct your stopping position | 
| • — | There is a problem | 
| • — • | Secure the train and track | 
| — • • • — | Driver and conductor to confer | 
| — • — | Power outage | 
| Fast Tapping | Cancel the last message sent | 
United States
In the United States, these are known as Communication Signal Appliance codes.
| Signal | Meaning[3] | 
|---|---|
| _ | When running, stop at once. | 
| _ | When standing, apply or release brakes. | 
| o o | When standing, start. | 
| o o o | When standing or running backward, back up two car lengths. | 
| o o o | When running forward, stop at next passenger station. | 
| o o o o | When standing, brakes have applied and released on rear car. Brake test completed. | 
| o | When spotting, switching, or making up trains, prepare to stop. | 
See also
- Whistle codes - used by locomotives to communicate with signal boxes
References
- ^ "Preparation and movement of trains on ERTMS lines" (PDF). Rail Safety and Standards Board. p. 24. Archived from the original (PDF) on 31 December 2013. Retrieved 28 December 2013.
- ^ "Chapter IV F. Duties of Staff Working Trains during Journey" (PDF). Indian Railways General Rules. South Eastern Railway. 2011. 4.51. Bell signals between Driver and Guard. Retrieved 7 February 2023.
- ^ "Communicating Signal Appliance" (PDF). Northeast Operating Rules Advisory Committee. 2008. p. 29. Archived from the original (PDF) on 23 July 2011. Retrieved 9 April 2011.