Omicron Lab CT Analyzer, User Manual

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Short Guide for Multi-Ratio CT Testing Using the CT SB2
4. Start the multi-ratio CT test by pressing the key on the CT Analyzer .
The red LED on the CT Analyzer flashes to indicate that the CT test is
running.
VA
cos
ϕ
or
Burden
cos
ϕ
Nominal burden for each tap combination.
To obtain correct measurement results, the nominal
burdens for the inner tap combinations (e.g. X1-X2 etc.)
should be smaller than the nominal burden for the full tap
combination according to the winding ratios of the tap
combinations (e.g. 25 VA for X1-X5, 12.5 VA for X1-X4
etc.). The
CT Analyzer supports this with an automatic
function.
As soon as the primary current I
pn
is specified for a tap
combination, the CT Analyzer automatically calculates and
sets the corresponding nominal burden and cos
ϕ
for this
tap combination. The nominal burden (VA) automatically
assigned by the
CT Analyzer can be changed manually by
the user for all tap and intertap combinations except the full
tap combination.
Note: The "VA" column is displayed by default when
opening the MR-Config. card the first time after initializing a
new multi-ratio test. Using the Op. Burden soft key you can
display the "Burden" column instead.
Operating burden and cos
ϕ
for each tap combination.
This column displays for each tap combination the
operating burden and cos
ϕ
specified in the CT-Object
card. The values cannot be changed by the user.
Note: The "Burden" column is displayed if you selected to
display the operating burden using the Op. Burden soft key.
Test In this column, select the tap combinations you actually
want to measure during the CT test. You can enable or
disable each single tap combination individually (disabling
the full tap combination is not possible). Disabling unused
tap combinations reduces the test duration.
I/0
I/0