307UM0100_01 May 2016
PD17x User Manual
Page 10 of 31
indica�ng to the user that a fault has occurred. The detector must be power cycled or reset via the pushbu�on in order
to clear the historical fault informa�on.
In the event of a vehicle passing over the inductive loop, causing a detect, the Green Channel LED will light up indica�ng
the presence of a vehicle and remain on for the dura�on of the detect.
It should be noted, however, that the Channel LED does NOT necessarily represent the output state of the relays. It only
represents the detec�on of a vehicle over the loop. The relay state could for example be different from the LED state in
the case of a pulse output a�er its pulse dura�on or a fault output. The only �me the Channel LED will go off, while a
vehicle is s�ll present, is if the channel is in limited presence mode and has expired.
The Red Power LED indicates that the unit is powered and func�onal. The red LED is also used as a communica�on
interface with the DU100 and DU700 to obtain diagnos�cs.
