Omicron CT SB2 User Manual page 58

CT Analyzer User Manual
Table 5-1: Name plate data in the CT-Object card
Parameter Description
I-pn Rated primary current of the CT.
I-sn Rated secondary current of the CT.
Standard Standard to be used for the CT test and the test assessment.
P/M CT type. Set "P" for a protection CT or "M" for a metering CT.
Class Rated accuracy class of the CT. This field becomes available after selecting the
CT type (protection CT or metering CT).
VA Rated power of the CT.
Note: For protection CTs of the IEEE C57.13 classes C, K and T, the VA
parameter is not accessible. Enter the rated secondary terminal voltage V
(see also "Specific parameters and settings displayed for IEEE C57.13 protection
CTs" on page 105).
Refer to table 8-4 on page 92 for detailed information on the parameters.
Note: Depending on the selected standard and CT type, other or further CT data may be necessary
for a correct assessment. If the "Check "*" settings before start" option is enabled in the default test
settings (see section 6.8.3 on page 71), all parameters that are required for assessment are marked
by a star "*" in the CT-Object card. In this case, no automatic assessment will be available if you do
not enter data for one or more parameters marked by a star "*" (see section 8.2.3 on page 92).
Table 5-2: Further information to be specified data in the CT-Object card
Parameter Description
ϕ
Burden / cos Burden value and cos
f Rated frequency of the CT.
Rprim Specified primary winding resistance (only available if primary winding resistance
measurement is enabled for the test).
Class mult. Class multiplying factor. (Can be used to increase the assessment level for the
factor ratio test. Example: Class multiplier 0.5 -> maximum accepted tolerance for the
ratio error is only half the standard tolerance).
Delta Correction factor for ratio measurement if a CT is installed inside a delta winding
transformer (see also "Measurement on a Δ (delta) winding transformer" on
compensation
page 38).
"Ratio 1": No correction is required.
"Ratio 2/3": If input PRIM is connected to the two terminals of that transformer
winding, the CT is in series with.
"Ratio 1/3": If input PRIM is connected to the terminals of a transformer winding,
the CT is not in series with.
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of the operating burden.
instead
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OMICRON