307UM0100_01 May 2016
PD17x User Manual
Page 9 of 31
3.2.7
Sensitivity (switch 4 and 3)
The sensitivity of the detector determines the change of inductance necessary to produce a detect. The PD17x provides
a selectable range of four sensitivity settings. Sensitivity is defined as a change in the inductance, with the PD17x it
ranges from 0.01% to 0.1%, with 0.01% being the highest sensitivity selection.
3.2.8
Frequency (switch 2 and 1)
The frequency switches are used to shift the operating frequency of the detector. This is primarily used to handle
situations in which more than one detector is used at the same site. The detectors must be set-up to ensure no crosstalk
(interference) occurs between adjacent loops connected to different detectors. This is achieved by ensuring that the
loops of the two detectors are spaced sufficiently apart (approximately 2 metres between adjacent edges) and also
ensuring that the detectors are set to different frequencies.
Sw2
Sw1
Frequency
Right
Right
High Frequency
Left
Right
Medium High Frequency
Right
Left
Medium Low Frequency
Left
Left
Low Frequency
3.2.9
Push button (Retune and Powerfail)
The push button can be used to initiate a retune or to switch Powerfail on or off depending on how long the push button
is held in.
Switch
Description
Hold
Function
Push
button
Reset
3 sec
This would initiate a detector retune
Power fail
status
10 sec
Hold for 10s to determine the state of Powerfail. If the LEDs
are ON, Powerfail is ON. If the LEDs are OFF, Powerfail is
OFF.
Power fail
toggle
30 sec
Holding for 30s will toggle the Powerfail status. The state of
Powerfail is known after holding for 10s. After 30s, if the
LEDs turn OFF, Powerfail is now OFF. If after 30s the LEDs
turn ON, Powerfail is now ON.
The PD17x has a Powerfail function which has been designed to retain the memory of a vehicle on the loop in the event
of a power fail situation. This is designed specifically for fail safe situations to retain the output state and prevent a glitch
on the outputs, in the event of a power failure.
3.3
Front Panel Indicators
The front panel indicators consist of a Red Power / Communication LED and one Green Channel LED.
There are four possible conditions which are indicated by the LED’s.
Idle condition – no vehicle is detected
Detect condition – a vehicle is detected passing over the inductive loop
Tuning condition – the detector is currently tuning to the loop
Fault condition – the detector is unable to tune to the loop as it is either out of operational conditions, such
as low signal strength or frequency out of range, or there exists a fault on the loop such as a short circuit
or an open circuit.
If a loop fault exists, the Green Channel LED will come on and flash at a rate of 2Hz indicating that the unit is trying to
tune. If the fault is self-healing the detector will continue to operate but the LED will flash at a slower rate of 1Hz
Sw4
Sw3
Sensitivity
Right
Right
(0.01%) - High Sensitivity
Left
Right
(0.02%) - Medium High Sensitivity
Right
Left
(0.05%) - Medium Low Sensitivity
Left
Left
(0.10%) - Low Sensitivity
