Manual
VEK S4
8
03/09
FEIG ELECTRONIC GmbH
2 Settings
The settings described in the following are performed either on the RS485 interface or the CAN interface. It
is recommended that the system be equipped with an operating unit for setting the detectors. The settings
can also be made from a laptop. Setup programs are available from FEIG ELECTRONIC. An appropriate
interface converter is also required.
2.1 Frequency
selection
The working frequency is set in order to
prevent cross-coupling.
Cross-coupling may occur with adjacent loops or loop lines on other detectors. It is therefore important that
two or more detectors do not operate on the same frequency. A frequency separation of at least 10 kHz
should be maintained for neighboring loops which are not connected to the same detector.
The detector operates in five frequency bands:
Band
Frequency range
0
automatic frequency setting
(Factory default setting)
1
30 - 40 kHz
2
45 - 55 kHz
3
60 - 75 kHz
4
80 - 100 kHz
5
105 - 140 kHz
It is recommended that all four loops of
one
detector be set to the same frequency band. Multiplexing
prevents cross-coupling between the 4 loops of a detector.
Note:
For loops whose inductance lies outside the recommended range (see Section 6 Technical data), the
frequency band setting can be restricted. The detector may calibrate to a different frequency than shown in
the above table. This is not a problem as long as there is no cross-coupling with other loops. The currently
set frequencies should therefore be checked.
For long loop supply lines it is recommended to use band 2..4 for frequency setting.
If automatic frequency setting is activated, the VEK S4 uses the device address to choose one of the
frequency range above. Please check the real frequency, because it can differ from the nominal frequency.
For additional notes on preventing cross-coupling
Æ
see
Section 1.6
Synchronisation
2.2 Multiplexing
sequence
The default multiplexing sequence is 1-2-3-4. To prevent cross-coupling with neighboring loops of another
detector in exceptional cases, you may change the sequence (e.g. 1-4-2-3).
Æ
see also
Section 1.6
Synchronisation
2.3 Classification
Both classification modules of the VEK S4 detector have separate loop parameters so that relevant
parameters per classification module can be set for the vehicle recording. The loop parameters include the
head gap, the amplitude factor for the sensitivity, the constant for the length adjustment and the loop length.
•
Head gap
The correct setting of the head gap is relevant for the accuracy of the speed measurement and the vehicle
length.
