VEK FG2-1
operating instructions
FEIG ELECTRONIC GmbH
12/99
19
Detector re-aligns automatically
Possible reasons
Measures
Interferences during the
switching of loads
Verification: check, whether the detector aligns automatically while switching contactors, motors or other
loads.
Remedy: - connect the detector’s supply main to another phase
- try to optimize the wiring
- carry out interference elimination measures
Interferences a at the
loop
Verification: check fluctuations in
mode with the helo of diagnostic device VEK FG2. They must
not
exceed 2 increments.
Remedy: - choose another frequency level.
-
Use of an 8-loop makes the loop more insensitive to interferences.
Note: compared to square loops, 8-loops reduce the responsiveness of the system!
Interferences at the loop
feeder
Verification: check fluctuations in
position with the help of diagnostic device VEK FG2 .
Fluctuation
must not exceed 2 increments.
Remedy: - the loop feeder has to be thoroughly twisted (min. 25 turns/m).
- do not install the loop feeder together with other live leads in one cable pit.
Interferences at the
detector
Verification: check fluctuations in the
position witht the help of diagnostic device VEK FG2. They
The detector must not align automatically when switching loads (e.g. barrier motor).
Remedy: - connect the detector’s supply main to another phase.
Insufficient mechanical
loop solidity
Verification: tap the surface above the loop with a beam and observe diagnostic device VEK FG2 in
position with regard to possible frequency jumping or permanent detuning.
changes in the loop geometry may cause positive as well as negative detuning of the detector.
Metallic objects in loop
area
Verification: use diagnostic device VEK FG2 in
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,
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)
Unstable base frequency
Possible reasons
Measures
Interferences at the loop Verification: check fluctuations in
mode with the helo of diagnostic device VEK FG2. They must
not
exceed 2 increments.
Remedy: - choose another frequency level.
-
Use of an 8-loop makes the loop more insensitive to interferences.
Note: compared to square loops, 8-loops reduce the responsiveness of the system!
Interferences at the loop
feeder
Verification: check fluctuations in
position with the help of diagnostic device VEK FG2 .
- do not install the loop feeder together with other live leads in one cable pit.
Interferences at the
detector
Verification: check fluctuations in the
position witht the help of diagnostic device VEK FG2. They
The detector must not align automatically when switching loads (e.g. barrier motor).
Remedy: - connect the detector’s supply main to another phase.