operating instructions
VEK FG2-1
12
12/99
FEIG ELECTRONIC GmbH
5.1.2 Electrical handicaps
In order to be able to guarantee smooth operation of a loop, the required electrical values of the loop have to
be observed.
Resistance
less than 20
Ω
Inductivity
50
µ
H to 1000
µ
H
Isolation resistance
More than 2M
Ω
Loop resistance and inductivity may be checked with the help of an LCR-meter. The loop’s insulating
resistance against ground has to be measured with a ground tester at a measuring voltage of at least 500V.
5.2 How to align the detector
The detector has to be aligned with the loops not occupied and is activated by pressing the reset key. For
most detectors, the alignment process is indicated by the flashing of a luminous diode. The alignment
process is completed after approx. 3s .
Automatic alignment is activated when switching on power supply (only for detectors without buffering). After
changing the frequency level, please carry out re-alignment!
5.3 How to adjust the detector
5.3.1 Sensitivity
The detector’s response level is determined by the selected sensitivity level.
For perfect adjustment, the loop is crossed by a passenger car. The minimum detuning that has been caused
by the car is then measured with diagnostic device VEK FG2. Possible sensitivity levels depending upon the
detuning are listed in the chart under „Selection of sensitivity“
Note:
In case of vehicles with a great distance between bottom of the car body and loop (lorries, trucksters, all-
terrain vehicles etc.), only the axles are detected if sensitivity is too low. In between the axles, the detector
falls back into the non-occupied condition. In this case, please choose a higher sensitivity level.
5.3.2 Stop period
For safety loops in for example barrier systems, the stop period should be set on
infinite
. With this
adjustment, vehicles on the loop are recognized and signalized for an infinite period of time. The busy signal
of the loop is not de-activated until the vehicle has left the loop.
If a
limited
stop period has been adjusted, (e.g. 5 minutes) it is easier for the detector to level out
interferences.
5.3.3 Frequency level
Loop frequencies have to be adjusted in a way that there is no coupling between other loops resp. detectors.
Please keep a frequency separation of at least 5 kHz for non-multiplex (VEK V...) and 10 kHz for multiplex
detectors (VEK M...).
Influences of high-frequency sources of interference may be avoided by selecting another frequency level.
With the help of the diagnostic device, the working frequency of the single channels may be measured and
checked in the
base frequency
position.
1
Order data for LCR-Meter and ground tester are to be found in the appendix
