Tag:traffic_signals=ramp_meter

Ramp Meter, are signalling devices typically found on motorway on-ramps to control the flow rate of joining traffic to promote free-flowing traffic. May be activated only during rush hours or periods of heavy traffic. They typically limit the number of cars per cycle, typically varying from 1-3 vehicles.

Tagging

Key	Value	Element	Comment
highway	traffic_signals		Required.
traffic_signals:direction	forward/backward		Typically "forward". Indicates the traffic signals signal only the traffic moving in the same direction as the OSM (highway) way upon which the they are placed: forward; or in the reverse direction: backward.
ref	*		Reference number or code, if present or at least assigned to specific traffic lights.
traffic_signals:countdown	yes / no		When there is display a countdown of the remaining time to wait or the time remaining where crossing.

Real World Examples

• 
  Ramp meter in California, USA
• 
  Ramp meter from Miller Park Way to I-94 east in Milwaukee, WI USA
• 
  Completed Ramp Metering site prior to signal activation on entry slip road to the A19 in Middlesbrough, UK
• 
  Ramp Meter in Auckland, NZ

Rendering

• 
  OSM Carto
• 
  BlindMap. Pedestrian traffic signals with sound

See also

• traffic_signals=bus_priority for a similar traffic light to give priority to busses.
• traffic_signals=emergency for a similar traffic light to give priority to emergency vehicles.