ABB PQFS Installation, Operation And Maintenance Instructions page 97

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Usage of an excessive CT ratio (including summation CTs). The
CT ratio limit is set at 20000/5.
After acknowledging the error message, the CT values existing before
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the start of the process will be restored and the automatic CT detection
procedure will be ended. The unsuccessful CT detection attempt is
recorded in the event logging window.
Conditions under which the automatic CT identification process may give
unsatisfactory results include:
The use of CTs with extremely high ratio's (> 20000/5). This will result in
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an error message indicating inconsistent CT positions. In this, the ratio
of the summation CTs that may be present should be included.
The presence of a low impedance directly downstream of the filter
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connection although the CTs have been correctly installed upstream of
the filter connection. This will result in wrong CT ratio's being found. In
that case the commissioning engineer can easily correct the CT ratio's
found.
The use of complex CT arrangements including summing CTs.
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It is recommended that the results obtained with the automatic CT detection
procedure be crosschecked with a visual inspection of the installation.
· Setting up the CT positions and ratio's using the manual setup procedure:
For entering the CT-settings manually, go to
[/Welcome/Settings/Commissioning/Man. CT settings]
For multi-unit filters the CT data for each unit has to be entered.
When entering the manual CT setup menu the user is subsequently prompted to
define for the selected filter unit of a filter system::
for the CT connected to the filter CT terminals X21/1-2 (Input 1):
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in which line (phase) is it installed (Line 1, Line 2, Line 3)
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does the CT (cabling) have the good orientation (Line x) or not
(-Line x)
Remark:
for the CT connected to the filter CT terminals X21/3-4 (Input 2):
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in which line (phase) is it installed (Line 1, Line 2, Line 3)
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does the CT (cabling) have the good orientation (Line x) or not
(-Line x)
Remark:
for the CT connected to the filter CT terminals X21/5-6 (Input 3):
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in which line (phase) is it installed (Line 1, Line 2, Line 3)
If the CT installation is correct, enter 'Line 1'.
If the CT is installed in the right phase but inversed,
enter '-Line 1'.
If the CT installation is correct, enter 'Line 2'.
If the CT is installed in the right phase but inversed,
enter '-Line 2'.
Manual Power Quality Filter PQFS ç The PQF-Manager user interface 97