PD130 Enhanced - User Instructions
Page 5 of 12
The frequency switches allow the loop to be shifted higher or lower depending on the switch position. The frequency of
the loop is determined by the loop size, and the frequency of the switch simply causes a frequency shift on the loop.
Where more than one detector is used the detectors must be set-up to ensure that there is no cross-talk (interference)
between the detectors. This can be 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.
As a general rule, the detector connected to the inductive loop with the greatest inductance should be set to operate at
the lowest frequency. Loop inductance increases as loop size, number of turns in the loop and feeder length increases.
5.1.2. Sensitivity
The sensitivity of the detector allows the detector to be selective as to the change of inductance necessary to produce an
output. There are four sensitivity selections and these are set as follows: -
SW4
SW3
Off
Off
- High
On
Off
- Medium-High
Off
On
- Medium-Low
On
On
- Low
5.1.3. Automatic Sensitivity Boost
Automatic sensitivity boost is a mode that alters the “undetect” level of the detector. This mode is selected by switch
No. 5 on the front of the enclosure and is as follows: -
SW5
Off
- Disabled
On
- Enabled
Automatic sensitivity boost causes the sensitivity to be boosted to a maximum on detection of a vehicle, and maintained
at this level during the presence of the entire vehicle over the loop. When the vehicle departs the loop and the detection
is lost the sensitivity reverts to the pre-selected level.
5.1.4. Filter Mode
The filter mode is selected with the mode switch No. 6. The filter produces a delay turn-on time of two seconds when a
vehicle
o
ccupies the loop. This is to enable
u
nwanted objects
(trolleys)
to pass over the loop without being detected.
The filter option may be used on any sensitivity setting and is selected as follows: -
SW6
Off
- Disabled
On
- Enabled
5.1.5. Pulse Relay
The pulse relay may be made to operate on detect (entry) or on “undetect” (exit) of a vehicle. This option is selected
from Switch No. 7 and is configured as follows: -
SW7
Off
- Pulse on Detect
On
- Pulse on Undetect
