Introduction; Designated Use - Omicron CT SB2 User Manual

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Introduction

2.1

Designated use

CT Analyzer is intended to perform automatic testing and calibration of low leakage flux current
transformers (i.e., CTs with non-gapped cores) in laboratories as well as on-site in utilities. Testing of
CTs with gapped cores is also possible with restricted accuracy. The following tests can be performed
using CT Analyzer:
• Burden measurement
• Residual magnetism measurement of CTs
• CT winding resistance measurement
• CT excitation characteristic measurement according to IEC 61869-2, IEC 60044-1, IEC 60044-6
(TPS, TPX, TPY, TPZ) and IEEE C57.13.
• CT ratio measurement with consideration of a connected burden
• CT phase and polarity measurement
• Determination of accuracy limiting factor, instrument security factor, secondary time constant,
symmetrical short-circuit current factor, transient dimensioning factor, remanence factor, knee point
voltage/current, class, saturated inductance and non-saturated inductance.
• Guessing of unknown CT parameters and automatic assessment based on these values (see section
2.2 below).
Using the Quick Test feature it is also possible to use CT Analyzer as a versatile multimeter with included
power source, e.g. for:
• Quick and easy resistance measurement, e.g. for wiring checks on the secondary side of CTs.
• Quick voltage ratio checks for VTs.
• Measurement of burden values, e.g., to determine the new burden value after changes of the relay
equipment. This allows the re-calculation of the CT test results for the new burden value by
CT Analyzer and thus makes it unnecessary to run an additional CT test in order to determine the
behavior of the CT with the new burden.
• Quick wiring checks using the CPOL2 polarity checker from OMICRON. Using the CPOL2 in
combination with the specific test signal provided by the CT Analyzer's Quick Test feature you can
check a series of test points (e.g., the burden wiring) for correct polarity.
CT Analyzer is intended exclusively for the applications described above. Any other use is deemed not
to be according to the regulations. The manufacturer and the distributor are not liable for damage
resulting from improper usage. The user alone assumes all responsibility and risk.
Ratio error and phase displacement measurements with direct (primary current
injection) and indirect test equipment (secondary voltage injection)
Alternative testing methods with indirect testing technology as applied by CT Analyzer provide similar
results to direct testing with high currents for CT designs having low leakage flux. Comparability is given
and both testing methods can be used without additional procedures. For CTs having a considerable
leakage flux (e.g., with large air gaps, low ratio or non-uniformly wound secondary windings), the ratio
error and/or phase displacement results may differ between the direct and the indirect testing method
due to the different testing methodologies requiring further procedures.
OMICRON
Introduction
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