1. Danish technical handbook for VMS What signs are VMS ?

2. Variable Message Signs are signs that can change between two or more sign faces including blank or neutral This is not a variable message sign A variable message sign must not alternate between messages, or flash with text, symbol or frame, or show motion symbols.

3. Different technologies present different options and limitations Danish technical handbook for VMS

4. Different technologies with different options/limitations Rotating prism Flip disc matrix Light guide LED

5. Particular options/limitations of variable message signs: 1) distinguish between categories 1, 2 and 3 5) criteria for continuous signs, quality of discontinuous signs 2) monochrome is only accepted for text 3) retroreflective signs shall be illuminated 4) for some luminous signs, the attention achieved with the opposite contrast is considered an advantage. Other VMS shall have normal contrast Concepts/requirements in the handbook: - limitations in the number and types of messages 1) - monochrome or with colour 2) - luminous or retroreflective 3) - normal or opposite contrast 4) - continuous or discontinuous 5)

6. 1) three categories: 1a number of predetermined messages 2a predetermined number of characters and lines 3free display of characters and symbols (full graphic) 2) monochrome is only accepted for text: Red borders have to be red, white parts have to be white (not yellow) 3) retroreflective signs shall be illuminated: The same criteria as for fixed signs are applied. Some details:

7. continuous signs (gaps between elements): discontinuous signs: (gaps between elements and stroke width) 5) criteria for continuous signs, quality of discontinuous signs Some details:

8. Quality: poor medium good continuous The font of Danish Road Signs has to be approximated

9. How big must the sign face be ? Danish technical handbook for VMS

10. Quality of lettersMaximum reading distance S Poor Medimum Good 4 m per cm letter height 5 m per cm letter height 6 m per cm letter height The necessary reading time is t = 2+n/3 seconds, where n is the number of standard informations on the sign (for instance symbols and city names) Basis: This calls for a maximum reading distance D = a+V  t, where: - a is the distance where reading must stop - V is the driving speed in metres per second Demand: Supply:

11. Driving speed 50 km/h 70 km/h90 km/h110 km/h130 km/h n ** letter height (capitals) 1137 143*159 170*180 202*202 202*224 240* 2145 143*170 170*194 202*219 240*244 240* 3153 170*181 202*208 202*236 240*264 285* 4160 170*191 202*222 240*253 285*284 285* * standard letter heights of Danish road standards ** number of standard informations Requirements for letter heights – good quality of letters

12. Driving speed 50 km/h 70 km/h90 km/h110 km/h130 km/h n ** letter height (capitals) 1206 202*238 240*271 285*303 340*336 340* 2217 240*254 285*291 285*328 340*366 405* 3229 240*271 285*313 340*354 405*396 405* 4241 240*287 285*333 340*379 405*426 405* * standard letter heights of Danish road standards ** number of standard informations Requirements for letter heights – poor quality of letters

13. Requirements for visual performance: - Retroreflective signs shall comply with requirements for fixed signs - Luminous signs shall comply with classes and requirements of EN 12966-1 !? Danish technical handbook for VMS

14. Classes and requirements of EN 12966-1 CharacteristicClassesRemarks colour of emitted lightC1, C2C2 is the more restrictive luminance of sign faceL1, L2, L3 *)L3 has the highest luminance contrastR1, R2, R3R3 has the highest contrast beam widthB1, B2, B3, B4, B5, B6, B7 B7 has the widest beam *) some additional classes apply for tunnels and specific situations Classes: Requirements: uniformity, no flicker

15. C1 colours White is permissive, but does not allow yellow LED’s

16. Luminance class L3 is preferred, but L2 is accepted (based on some small studies)

17. Contrast class R2 is accepted (no studies) R1 R2 R3

18. Beam width class B4 is normally preferred (depends on the situation) class B4

19. Additional requirements for visual performance Danish technical handbook for VMS

20. Illuminance on sign face Colour of field on sign face whitewhite/ yellow greenredblue 40 000 lx62 20052 70037 20018 60015 5006 200 4 000 lx11 0009 3506 6003 3002 7501 100 400 lx3 0002 5501 800900750300 40 lx1 2501 065750375315125  4 lx 3753202251159537,5 Maximum permissible luminances (all luminance classes) Those at 40 000 lx are too high (eye damage) --------- -------- -------- -------- -------- ------- 31 100 26 350 18 600 9 300 7 750 3 100 Danish handbook: reduction to 50%

21. Illuminance on sign face Colour of field on sign face whitewhite/ yellow greenredblue 40 000 lx6 2005 2703 7201 8601 500620 4 000 lx1 100935660330275110 400 lx300255180907530 40 lx200170120605020  4 lx 605136187,56,0 Minimum luminances (luminance class L2) Standard; a luminance control is implied, but not secured       Danish handbook; requirements for: - detector (directional and spectral) - luminance - illuminance function

22. Illuminance on sign face Colour of field on sign face whitewhite/ yellow greenredblue 40 000 lx6 2005 2703 7201 8601 500620 4 000 lx1 100935660330275110 400 lx300255180907530 40 lx200170120605020  4 lx 605136187,56,0 Minimum luminances (luminance class L2) Standard; a balance between colours is implied, but not secured (for instance maximum red is higher than minimum white)    Danish handbook; requirements are added

23. Handbook Requirements: No disturbing luminance variations No visible changes between luminance steps more often than 5 seconds

24. Physical requirements: - VMS shall comply with classes and requirements of EN 12966-1 Danish technical handbook for VMS

25. ParametersClass designationRemarks TemperatureT1, T2, T3 PollutionD1, D2, D3, D4D4 is the more restrictive ProtectionP1, P2, P3P3 is the more restrictive *) a classification of IP classes ? (IP45, IP55 and IP66) *) Classes and requirements of EN 12966-1 Classes: Requirements: Resistance to loads, impact resistance, vibration resistance, nominal voltage, mains frequency, power up activation, switch off voltage response, voltage interruption, temporary overvoltage, electrical safety and electromagnetic compatibility Temperature: T2 is preferred (-15 to +55  C) Pollution: D class (conductivity caused by dust, condensation, rain and snow) ? Protection: minimum IP 55

26. Other requirements Danish technical handbook for VMS

27. Messages: when the sign is not in use (black) when there is a failure (out of order) Change over time: Control and monitoring (e.g. logging) fast medium slow t  1 seconds 1 < t  3 seconds 3 < t  10 seconds

28. Thank you for your attention Danish technical handbook for VMS