166 The PQF-Manager user interface
Manual Power Quality Filter PQFM
8.6 Step 5: Automatic and manual CT detection procedure
WARNING: Do not filter harmonics or do reactive power compensation/balancing
when the CTs have not been set up correctly. Failure to adhere to this guideline will
result in erratic filter operation.
Refer to
Section 6.9
and
Section 6.10
for the CT selection and installation guidelines.
WARNING: Before programming or detecting the CTs, make sure that:
−
The CTs have been connected to the filter CT terminal X21. For multi-filter
configurations all the units of a filter system have to be supplied with the same CT
information (daisy chain principle with return path as shown in
−
All shorting links in the CT path have been removed (i.e. on the CTs, on the filter CT
terminal X21 …).
CT shorting links are provided with the filter for servicing purposes, but they are not
installed by default on the X21 terminal.
The CT settings can be detected with the automatic CT detection feature or in a
conventional way. The automatic CT detection approach allows compensating for
physical connection errors in software. For multi-unit filters, the automatic CT detection
feature will automatically try and detect the CT-connections for the different units.
8.6.1
Automatic CT detection procedure
The automatic CT detection procedure and the precautions to take when using it are
explained in detail in
Section 7.9.2.3.
Section 8.6.2
discusses a way to check the CT installation if the automatic CT detection
procedure is not used or does not find the correct results.
NOTE: When the automatic CT detection procedure is started, the filter will
automatically deactivate all user requirements for filtering, reactive power
compensation and balancing. After the procedure has finished, the user has to
reprogram these parameters into the filter.
8.6.2
Manual CT detection procedure
Refer to
Section 7.9.2.3
for guidelines on how to enter data when using the manual CT
setup.
The following procedure will allow you to check the CT connection. This step only has to
be executed if the CT setup could not be detected automatically. For filters consisting
of more than one unit, it is necessary to check the CT connections for each individual
unit.