4.6 After Repair Tests
After any repair to a filter or after any testing of a filter
suspected of being faulty, follow this procedure to ensure
that all circuitry is functioning properly before returning
the unit to operation.
1.
Perform visual inspection procedures as described
in
2.
Perform the static test procedures to ensure that
the unit is safe to start.
3.
Apply AC power to the unit.
4.
Copy parameter settings to the LCP memory
0-50 LCP Copy
for backup.
5.
Program the filter according to CT installation in
the following parameters: Location (
300-26 CT
Placement
), CT Primary Voltage (
300-22 CT
Nominal Voltage
).
6.
Perform an Auto CT-detection (300-29) if the
following conditions are met: the CTs are installed
on the PCC side (towards the transformer), CTs
do not use sum transformers, the filter is not
supplied through a transformer, and the filter is
>10% of the CT primary.
7.
Check the filter parameters according to CT
installation in the following parameters: Primary
Rating (
300-20 CT Primary Rating
), Sequence
(
300-24 CT Sequence
), Polarity (
300-25 CT Polarity
).
8.
Mount the CT short at all three CT inputs on the
CT input terminal (factory pre-mounted).
9.
Provide the active filter with a run command.
10.
Check that the filter current shown on the LCP is
lower than 15% of the nominal filter current. If
higher, conduct a hardware fault inspection.
11.
Stop the active filter and remove all three CT
short lugs.
12.
Check the filter parameters according to
application requirements in the following
parameters: Priority (
300-01 Compensation Priority
),
Harmonic Selection Mode (
300-00 Harmonic
Cancellation Mode
and
300-30 Compensation
Points
), and Cos fi Reference (
300-35 Cos-phi
Reference
).
13.
Provide the active filter with a run command.
14.
Monitor that the total harmonic current and
voltage distortion is reduced. If not, check CT
input/installation for faults or configuration errors.
15.
Copy parameter settings to the LCP memory
0-50 LCP Copy
for backup.
Troubleshooting
VLT Advanced Active Filter AAF006 D and E Frames Service Manual
4-12
MG90Z122 - VLT
®
is a registered Danfoss trademark
4
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