The light receptor measures the average luminance within a fixed viewing angle (set during manufacture) within a range of 10 to 40º. The standard instrument has an acceptance angle of 20º (as recommended by Commission Internationale de l´Eclairage (C.I.E.), publication 88, 2004). The luminance measurement range is scalable between 0 – 10,000 cd/m2.
The photometer installation point is typically at the driver’s safe stopping distance from the tunnel portal, based on the maximum road speed.
The LUMIOS-MkIII Photometer has onboard SCADA / PLC interface options, including Current Outputs, Digital Relays and RS485 (Modbus RTU). Optional wipers and pumped washer systems are also available for more demanding environmental conditions.
To learn more about the Acoem LUMIOS range of photometers please contact us or call our office and we will be happy to help specify a photometer for your next tunnel lighting project.