Photo Electric Control Unit (PECU) is an electronic switch which is triggered at a specific light level. Based on thermal, electronic or microprocessor technology,
photocells operate in a number of ways depending of the level
of accuracy required.Dusk to dawn sensing – generally inaccurate light
detection where the lamp switches ‘ON’ as night falls and
switches ‘OFF’ shortly after sunrise.Light level detection – more accurate light detection
where the photocell switches at pre-set light levels both at
sunset and sunrise, typically 70/35, 55/28, 35/18 or
20/20 lux. Negative switching sets the lamp to ‘OFF’ at a
lower level than ‘ON’, with positive switching acting
in reverse.
