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Instruction Manual
Important notes: During the commissioning
tests, the record of the values found for each
type of test performed shall be made for
comparisons with the results that will be
measured during the lifetime of the CVT. The
values measured in the factory tests are
important, but also important are the results
of the commissioning, for each CVT. The
comparisons between the results of the tests
make sense for the data measured in the
field, since they determine the monitoring
and evolution of the values and the
performance of each CVT, when a history of
their lifetime can be obtained.
8.1. On-site test methods
In general, on-site test equipment can
provide a test voltage of up to 10 kV
for
measurement
procedures and techniques are not
the
same
equipment.
manual of the test system. The
precautions and test principles given
below are for reference.
8.2. Care and precaution
Before handling capacitive units,
•
short circuit and ground them for at
least 30 seconds to avoid any
possibility of stored loads.
• The maximum voltage that can be
applied to the carrier terminal cable
after removal from the "HF" terminal
(CD low voltage terminal) is 2 kV.
• The maximum voltage that can be
applied to the ground terminal of the
EMU ("N" or "H2") after removing it is
2 kV.
• The nominal voltage of the
intermediate voltage terminal (or
nominal voltage of the EMU) is
indicated on the nameplate of the
© GE Grid Solutions
purposes.
The
for
different
test
Check
the
operating
CVT. It is recommended that the
lower
capacitor
measurement be performed at a
voltage less than 10% of the rated
voltage of the lower CD.
• After removing the "HF" and "N" or
"H2" terminal connections, do not
energize the unit at rated voltage.
• Apply the voltage in a controlled
manner.
• Redo any connection that has been
removed during the on-site tests.
8.3. Capacitance measurement
The following figures show how to
connect
typical
measurement equipment for the
measurement of each capacitance of
an OTCF CVT.
Since
the
intermediate
terminal of the lower capacitive
module for accessing the capacitances
C1-1
and
C(2)
accessible, the user can determine
the total capacitance
measured values of C1-1 and C2.
The presence of the internal chock
coil
does
not
measurements for frequencies of
50Hz or 60Hz.
CVT with capacitive divisor in a
single module
capacitance
insulation
voltage
is
not
directly
from
the
influence
the
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