In 1955 the NS switched to a new signaling system. The new 1955 signaling system gave an
almost complete de-coupling of speed and clearance signalling. The base signal pole has
three lights (In the beginning there was a fourth, yellow, light but that light has been abandoned.)
The three basic lights have different colors, green, yellow and red.
Additionally, a matrix board board with a number for extra speed signalling can also be shown.
The three lights control the clearance of the track ahead of the train. Only one light can be shown at a time. The yellow light gives a speed signal, at first 30km/h, later 40km/h. Green allows passing and red orders stop.
If a specific speed has to be forced upon the train, a matrix board can be shown.
|green||green flash with number 7||green flash|
|passing permitted||passing permitted with 70 km/h||passing permitted with 40 km/h|
|The lights are fitted with a long "sun cap" above each light to prevent sunlight from falling on the mirror and shining back to the driver.|
|The red light is always at the the bottom. With heavy snow it is believed that
snow can stay on top of the "sun cap" and thus prevent a light from being seen.
When red is at the bottom, no snow lying on a "sun cap" can obscure this light.
|The matrix board have more reflectors in it than necessary to show a number. If sunlight reflects on the mirrors, a nonsense figure would be displayed.|
|reduce speed to 40km/h the next signal can show a stop sign.||Ride on sight, reduce speed (max 40km/h) so that the train can stop before any obstackel.|
Why is the green light flashing when a number is shown and yellow not? Fail-safe! Green flash is a more restrictive signal than green flash 6. So when in case of a failure the number is not shown, yellow 6 will turn into yellow, being a more restrictive signal. Green 6 would turn to green and the driver would think that track speed is allowed, which is not. Therefore the flash is introduced.
|yellow with number 6||yellow with flashing number 8||red|
|reduce speed to 60 km/h. This speed has to be reached before the next signal and the next signal will not show stop||reduce speed to 80 km/h. This speed will not be reached before the next signal but braking has to continue until the desired speed is reached||stop|
|passing permitted with 40 km/h.||passing permitted with 40 km/h, next signal will show stop.||yellow blinking||red|
|Ride on sight (an other train can occupy the track).||stop|
|E-mail to Rik|
|updated : februari 12th,2004||Designed by:|
Rik Boers & Bart Ponsen