CPC 100
V 3.20
Current Transformer - 8
Current
Transformer
Use the
CTLow Power
test card to measure the ratio of a low-power current transformer with a
built-in burden and an output voltage that is directly proportional to the primary current.
Nominal secondary voltage of Rogowski coil
Nominal frequency
of the Rogowski
coil’s secondary
voltage
Primary injection
current
Select to manually
enter V sec instead
of measuring it
Nominal primary
current of
Rogowski coil
Select check box for
automatic test, clear for
manual test
Frequency of
injected current
I test
Secondary
voltage
Calculated
secondary current
*)
Polarity:
OK
= phase I sec - phase I prim
= - 45 ° < 0 ° < + 45 °
NOTOK
= all other cases
Ratio: Iprim / Isec and deviation of current ratio in %
Output range
Actual output
current
*) Note that the current
I sec
does not really exist in the system. It is a calculated current only.
Electronic protection relay with low-voltage
input (e.g., 22.5 mV at I nominal)
Relay
Built-in burden
CT
Shielded cable with
twisted wires
Output range
Nominal secondary voltage
Select to stop test
automatically when
measurement is done
Select to enter
secondary voltage
instead of
measuring it
Measured
secondary
voltage
Actual current
injected into
CT’s primary
side
Ratio Iprim. / Isec.:
Isec act x (Iprim nom/Iprim act)
and deviation in %
((Kn x Isec - Iprim)/Iprim) x 100 %
Polarity:
OK
= phase I sec - phase I prim
= - 45 ° < 0 ° < + 45 °
NOTOK
= all other cases
Phase angle
relative to Iprim
Nominal primary
current
Primary
injection
current
CTRogowski
CTLowPower (Ratio)
