View source for Approach Alarms

== Approach Alarms ==

Most of the cameras display "Approach Indicators" to tell you what is coming, about to pass or recently passed. 

Additionally, you can set audible alarms to tell you when something is coming.

The approach indicators use the signalling berths either side of the camera position (the data used by our diagrams). 
Most cameras have berths we show as 

* Single-yellow - approaching (distant : two berths out from camera location)
* Double-yellow - approaching (near : one berth out from camera location).
* Green - passing (berth at camera location)
''This is also used for trains 'in section' where there is no signalling feed but a train has left the last reporting location and could show for several minutes before reaching the camera.''
* Red - train has passed the camera location (berth beyond camera) 

Cameras near a station, loop or siding, may not have the yellow aspect options available. These may show as "At Platform" or "Waiting"
* White with red bar

* Double-yellow is also used or trains 'in section' where there is no signalling feed but a train has left the last reporting location

The Green aspect is the safest option and should work on almost all cameras - but may provide only a few seconds warning. Some experimentation may be needed to discover what works best on a particular camera. 

There is an option to exclude regular passenger trains from alarms. This means that the alarms are only triggered for freights, specials, test-trains and light-engines or even a specific headcode.