Omicron Lab CT Analyzer, User Manual

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CT Analyzer User Manual
84
Class * Accuracy class of the CT.
Possible values: Depending on the selected standard or ?
1
.
Default: As defined in the default test settings.
This parameter is only displayed, after the parameters "Standard" and "P/M"
have been defined or determined by the
CT Analyzer . Depending on these
parameters, the parameters for the CT class can be selected using the soft
keys.
Note: The class can be selected by soft keys or is determined by the
CT Analyzer during the test. Automatic determination during the test only
works for IEC 61869-2 or IEC 60044-1 metering CTs and IEEE C57.13
metering CTs. If the question mark has been entered for the "P/M" parameter,
the "Class" cannot be defined by the user but is automatically determined by
the
CT Analyzer instead.
* This parameter is relevant for assessment. No automatic assessment is
available if the user did not enter data for this parameter prior to the test (see
page 82).
For IEEE C57.13 metering CTs only:
An additional soft key
Assess @ VA is available for metering CTs according
to IEEE C57.13. Use this option if the accuracy class of the CT only applies
to one specific burden.
CT assessment is normally performed for the maximum burden specified
("VA" or "Burden" parameter)
and all lower burdens defined in the standard.
Example: If the burden specified is B-0.9, the assessment is performed for
the burdens B-0.9, B-0.5, B-0.2 and B-0.1 (and the electronic burdens E-0.2
and E-0.04).
Selecting the Assess @ VA option in addition to the class setting will cause
the CT Analyzer to consider only the burden value specified prior to testing
for the CT assessment. The ratio table and the phase table in the Ratio card
then only show the error for this specific burden (see section 6.7.5 on page
123).
When Assess @ VA is selected, the soft key changes to Assess all VA to
enable deactivation of this option.
Parameter Description