These data sets show the illuminance provided by the electric lights. The diagram on the left shows illuminance levels with both banks of lights on and the diagram on the right shows only the front bank of lights. Because of the programming of the lighting system, this latter condition is most likely in dark conditions. The north bank of lights will not turn on until outside illuminance levels drop below 150 fc, which will typically not happen during daylight hours even when the weather is very overcast.
