Omicron CT SB2 User Manual page 233

Table 8-11: Soft keys available for the excitation graph (continued)
Soft key Description
By pressing one of these soft keys you can display the measured excitation graph and
knee point as defined in the respective standard.
IEEE C57.13 displays the knee point for the 45° tangent. After pressing this soft key, its
labeling changes to IEEE C57.13 (30°) to enable the display of the knee point for the
30° tangent. 30° is recommended for gapped cores in IEEE C37.110, chapter 4.3.
Note: The test report only contains the graph for the standard selected in the CT-Object
card.
Viewing the measured values for different points on the graph
By default, the knee point values are displayed after opening the excitation graph page. However, you
can also view the corresponding voltage, current and inductance values for any point on the graph. To
select a specific point on the graph,
► either use the soft keys (Cursor Up, Cursor Down)
► or enter a specific voltage or current value using the keyboard:
► Select the desired edit field using the
► Enter the desired voltage or current value using the keyboard.
► Press the
respective fields (e.g. "V-meas" and "L-meas" if you have entered a current "I-meas").
Figure 8-7: Entering a current value to display its corresponding voltage and inductance values on the
excitation graph
OMICRON
key to apply the entered value and read the corresponding values in the
CT Analyzer test cards for MR Test mode
cursor keys.
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