Feig Electronic VEK FG2 Series, Руководство по эксплуатации

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operating instructions VEK FG2-1
18 12/99 FEIG ELECTRONIC GmbH
Influences caused by
armouring or metal foil Verification: cross the loop with a vehicle and check the detuning with diagnostic device VEK FG2.
Note: the loop is deadened by strong armouring or metal foil which is located in the concrete floor
under the loop. Such loops have a reduced sensitivity.
Remedy: -to a certain extent, the influences caused by strong armouring or metal foil in the concrete floor
may
be leveled out by increasing the detector’s responsiveness.
-spare the metal foil in the loop area.
Wrong alignment Verification: the diagnostic device VEK FG2 shows a permanent negative detuning.
Detector has been aligned with the loop being occupied and deadened.
Remedy: re-align the detector with the loop not occupied.
Insulation fault Verification: check insulating resistance of the loop and feeder between feeder end and earth potential with
the
help of an insulation tester, such as the Isolavi. The insulating resistance has to be higher than
2 M.
Remedy: eliminate the source of errors, install new loop resp. loop feeder
Loop feeder is too long Verification: check feeder length between detector and induction loop according to detector data sheet.
Remedy: -install interstage transformer VEK ANPASS between detector and loop feeder.
- place the detector resp. loop elsewhere.
Insufficient mechanical
loop solidity Verification: tap the surface above the loop with a beam and observe diagnostic device VEK FG2 in
detuning position with regard to possible frequency jumping or permanent detuning.
Note: changes in the loop geometry may cause positive as well as negative detuning of the detector.
Positive detuning may lead to a permanent seizure of the detector. In case of negative detuning,
the
detector becomes more insensitive. Extreme frequency jumps may lead to a re-alignment of the
detector.
Remedy: -please make sure that the loop is of sufficient mechanical solidity; there must not be any
deformations in the loop geometry when crossing it with a vehicle.
- the loop must not move compared to the ground armouring.
- for installation under paving stones, please always use finished loops.
Metallic objects in loop
area Verification: use diagnostic device VEK FG2 in detuning position to check frequency fluctuations and
-jumps caused by movements of the metallic object.
Note:
If metallic objects (e.g. manhole covers, grates, loose gates etc.) are surrounded by the loop,
their
movements may cause detunings of the resonant circuit. Should there be permanent, negative
frequency changes, the system may not recognize vehicles which do only cause minor detuning.
Remedy: - re-install loop, so that the metallic object is now outside the loop field.
- replace the metallic object by a non-metallic one.
- prevent movements of the metallic object.
(if necessary, fix manhole covers and grates by welding)