See my discussion entries.

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Note added at 57 mins (2014-11-12 16:24:52 GMT)
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GWIT:
verkeerslicht =traffic light
verkeerslichtinstallatie = signal head

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It seems they are also referred to as traffic lights when use on loading bays. See e.g.:

"Loading dock accessories: Traffic lights

The Fen-Bay traffic light is a must on loading bays without a working traffic light system you could be contravening current health & safety legislation the system comes complete with highly visible 200mm 98 LED lenses and operates at 24 to Save on energy cost the system is using only 8 Watts.

Traffic light signs Designed to give clear instruction to the driver and help eliminate costly damage to the loading dock." (http://www.fen-bayservices.co.uk/loading-dock-equipment.php?... )

The ref posted by the asker refers to a light that can be purchased in orange, green and red. That is, it's used as a part of a traffic light system to guide trucks in and around the loading dock.

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"Warning lights
It is possible to include traffic signal lights to work either independently or in conjunction with a warning light in the control station to improve safety on or around the loading bay. As soon as the loading and unloading system is activated, the external stop light switches from green to red (unsafe to depart), and as soon as the dock leveller lip is positioned on the vehicle bed, the warning light on the control box inside, switches from red to green. As soon as loading and unloading is completed, and the system returned to its home position, the external signal light switches from red to green and the warning light inside switches from green to red (unsafe to load and unload)." (http://test.loading-systems.co.uk/node/314 )

In this example, the "warning lights" are in the "control station", and the (green/orange/red) "traffic lights" are the ones on the wall next to the loading dock entrance.


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Note added at 58 mins (2014-11-12 16:26:15 GMT)
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attentielicht = verkeerslicht
• here it's called an "attentielicht": https://www.informatiebord.nl/p/1592/verkeerslichten-masten/...
• here the same thing is called a "verkeerslicht": https://www.informatiebord.nl/c/12/verkeerslichten-masten/ve...

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