Unaffected by wind or atmospheric pressure Remote test feature.
The optical smoke detector uses an internal pulsing LED and photo-diode at an obtuse angle.
In the event of smoke entering the chamber, the light pulse from the LED will be scattered and registered by the
photo-diode. The detector will then enter the alarm state and the indicator LED lights up.
Optical smoke detectors incorporate a pulsing
LED located in a chamber within the housing of
the detector. The chamber is designed to
exclude light from any external source.
At an angle to the LED is a photo-diode which
normally does not register the column of light
emitted by the LED. In the event of smoke
from a fire entering the chamber, the light
pulse from the LED will be scattered and
hence registered by the photo-diode. If the
photo-diode “sees” smoke on the two following
pulses, the detector changes into the alarm
state and the indicator LED lights up. The
detector housing is identical to that of the
ionisation detector but has an indicator LED
which is clear in quiescent state but produces
red light in alarm.
