Omicron Lab CT Analyzer, User Manual

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Operating and Configuring the CT Analyzer
Temperature Select the temperature unit ( °C or °F ) and the default
values for the ambient temperature and the reference
temperature (for winding resistance measurement and
calculation).
Date/Time Clock settings for the device-internal clock.
Display Contrast Display contrast adjustment.
Accur. Limiting
Error Graph Enable or disable the accuracy limiting error graph.
This graph is primarily required for Chinese standards. It
shows the maximum possible primary current (K * I
pn
)
that can flow over a specific burden without exceeding the
accuracy limit (5% or 10%).
Start Delay Allows the definition of a delay time of up to 10s for the
actual test start after pressing the start button.
You can apply the defined delay for the burden test, the
residual magnetism measurememt, the primary winding
resistance measurement and the secondary winding
resistance measurement.
Min. VA at M cores
Isn 5A Applies to IEC 60044-1 metering CTs with I
sn
= 5A only!
Here you can set the minimum VA value used for the CT
assessment to
3.75VA . This means, selecting the
3.75VA soft key will cause the CT Analyzer to assess the
CT only up to a lower nominal burden limit of 3.75VA
instead of 1VA. When 3.75VA is active, it is not possible
to enter VA values lower than 3.75VA in the
CT-Object
card.
Selecting
0VA deactivates this option. Assessment is
then performed up to a lower burden value of 1VA. This
is the factory default which is suitable for most cases.
You should not change it without important reason.
C57.13 electronic
burdens Applies to IEEE C57.13 metering CTs only!
Enable or disable the use of the electronic burdens E-0.2
and/or E-0.04 for CT Assessment. If enabled, these
values are offered in the set of soft keys available for the
"VA" and "Burden" parameters in the
CT-Object card. In
this case, CT assessment is also performed for the
electronic burden values in addition to the burden values
defined in the standard.