The TunnelTech 601 Luminance photometer monitors the average luminance of a tunnel entrance and its surroundings. In accordance with Commission Internationale de l´Eclairage, (C.I.E.), publication 88, 1990 recommendations, the photometer monitors the average luminance within a 20 degree angle over a standard range of 0 – 6,500 cd/m2.
The detector is a metal/glass encased silicon diode photocell which is filtered to give a response that mimics the performance of the human eye. The detector is perfectly linear within its measuring range and has an instantaneous response to changing light levels.
Compliant with Commission Internationale de l´Eclairage, (C.I.E.), publication 88, 1990
Measurement of tunnel entrance luminance – 0 – 6,500 cd/m2
Calibrated using standards traceable to UK National Physical Laboratory
Thermostatically controlled heater unit
Rugged Aluminium housing to IP66