Inspect For
Description
EMC consider-
ations
•
Check for proper installation regarding
electromagnetic compatibility. Refer to the
active filter instruction manual and
of this manual for
further details.
Environmental
conditions
•
Under specific conditions, these units can be
operated within a maximum ambient of 45° C
(113° F).
•
Humidity levels must be less than 95% non-
condensing.
•
Check for harmful airborne contaminates
such as sulfur-based compounds.
Grounding
•
This unit requires a dedicated ground wire
from its chassis to the building ground.
•
Check for good ground connections that are
tight and free of oxidation.
•
The use of a conduit or mounting the filter
on to a metal surface is not a suitable
ground.
Input power
wiring
•
Check for loose connections.
•
Check for blown fuses.
•
Check for proper fusing.
Grid
conditions
•
Check the grid-connected loads.
•
Check that the PF capacitor banks are
installed and tuned.
•
Verify that the AC coils are in front of non-
linear loads.
Vibration
•
Look for any unusual amount of vibration
that the unit may be subjected to.
•
The filter should be mounted solidly and
subject to vibrations of less then 1G.
•
If shock mounts are employed for higher
vibrations, check these for cracks or
malfunction.
Table 4.1 Visual Inspection
4.4 Fault Symptoms
4.4.1 No Display
The LCP display provides two display indications. One by
means of the backlit LCD alphanumeric display. The other
is three LEDs near the bottom of the LCP. If the power-on
LED is illuminated (green), but the backlit display is dark,
this indicates that the LCP itself is defective and must be
replaced.
On
Warn.
Alarm
130BP044.10
Figure 4.1
Be certain, however, that the display is completely dark.
Having a single character in the upper corner of the LCP or
just a dot indicates that communications may have failed
with the control card. This is typically seen when a serial
bus communication option has been installed in the filter
and is either not connected properly or is malfunctioning.
If neither indication is available, then the source of the
problem may be elsewhere. Proceed to
to carry out further troubleshooting steps.
4.4.2 Intermittent Display
Cutting out or flashing of the entire display and power
LED indicates that the power supply (SMPS) is shutting
down as a result of being overloaded. This may be due to
improper control wiring or a fault within the filter itself.
The first step is to rule out a problem in the control wiring.
To do this, disconnect all control wiring by unplugging the
control terminal blocks from the control card.
If the display stays lit, then the problem is in the control
wiring (external to the filter). All control wiring should be
checked for shorts or incorrect connections.
If the display continues to cut out, follow the procedure
for No Display as though the display were not lit at all.
Troubleshooting
VLT Advanced Active Filter AAF006 D and E Frames Service Manual
MG90Z122 - VLT
®
is a registered Danfoss trademark
4-3
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