CPC 100
V 3.20
Current Transformer - 6
Current
Transformer
Select the option
Intermittent
to save power in the 800A AC output range and define a pulse
duty cycle for the output signal:
Use the
CTRatioV
test card to measure a current transformer’s ratio. To do so, feed a voltage
of up to 500 V from the
2kV AC
output to the transformer’s secondary side.
The preferred method for CT ratio measurement is current injection using the
CTRatio
test card.
However, on some GIS CTs or bushing CTs on power transformers where the primary current
path is not accessible, the method described in this section is the only solution.
To measure the CT ratio using the
CTRatioV
test card, connect the
2kV AC
output to the CT’s
secondary winding and the
V2 AC
input to the main conductors, e.g. on a power transformer to
the transformer’s bushings of different phases.
T on
:
time span the signal is applied to the output
T off
:
time span the signal output is paused
Select output
range
Amplitude
Enter results
manually
A T on / T off ratio of 2.000 s / 9.000 s means the signal is applied for 2 seconds,
then paused for 9 seconds. After that the cycle repeats.
DANGER
Death or severe injury caused by high voltage or current
Feeding test voltage to a tap of a multi-ratio CT can cause life-threatening voltages on
other taps with higher ratios.
►
Do not touch tapped windings.
Burden
CT
Polarity Check
CTRatioV (with Voltage)
