307UM0200_01 May 2016
PD27x User Manual
Page 5 of 30
2. Technical Data
2.1 Functional data
Tuning
Fully Automa
�
c with op
�
on to enable Automa
�
c Frequency Selec
�
on (AFS)
Self-tuning range
20 µH to 1500 µH
Sensi
�
vity
Four steps adjustable on the DIP switches (High, Medium-High, Medium-Low, Low)
Op
�
ons available are 0.01% ΔL/L, 0.02% ΔL/L, 0.05% ΔL/L and 0.10% ΔL/L
ASB (Automatic Sensi
�
vity Boost) is selectable via the DIP switches
Frequency
With AFS switched on the channel tunes automatically to one of five possible frequencies
There are four selectable frequency op
�
ons with AFS switched off
Opera
�
ng frequency of 18 – 110 kHz (Determined by loop geometry and frequency se
�
ng)
Output Configura
�
on
2 output relays
User configurable for:
Presence on detect
Pulse on detect
Pulse Output Dura
�
on
150ms
Presence Method
Permanent or Limited presence
Presence Time
Infinite when the unit is on Permanent Presence
Dependant on level of detect and environmental condi
�
ons when on Limited Presence
Dri
�
Compensa
�
on Rate
Approx. 1 %
∆
L/L per minute
Response Times
Detect:
53.0 – 73.0ms
Undetect:
280.0 – 350.0ms
Subject to sensi
�
vity level, level of detect and speed of vehicle over the loop
Visual Indications
1 x Power / Status LED – Red
2 x Channel Status LED – Green
Reset
Holding the reset bu
�
on for 3s ini
�
ates a retune
Surge protec
�
on
Loop isola
�
on transformer, gas discharge tubes, and Zener diode clamping on loop input.
Power Fail
Infinite memory reten
�
on of detector state on power failure (provided certain criteria are
met refer to sec
�
on 4.5). This func
�
on can be turned on and off via the Reset push bu
�
on.
