Table. 5.6.1 - 172. Measured inputs of the CTS function.
Signal
Description
Time base
IL1RMS
RMS measurement of phase L1 (A) current
5ms
IL2RMS
RMS measurement of phase L2 (B) current
5ms
IL3RMS
RMS measurement of phase L3 (C) current
5ms
I01RMS
RMS measurement of residual input I01
5ms
I02RMS
RMS measurement of residual input I02
5ms
I1
Phase current's positive sequence component
5ms
I2
Phase current's negative sequence component
5ms
IL1Ang
Angle of phase L1 (A) current
5ms
IL2 Ang
Angle of phase L2 (B) current
5ms
IL3 Ang
Angle of phase L3 (C) current
5ms
I01 Ang
Angle of residual input I01
5ms
I02 Ang
Angle of residual input I02
5ms
The selection of the AI channel in use is made with a setting parameter. In all possible input channel
variations the pre-fault condition is presented with a 20 ms averaged history value from -20 ms from
START or TRIP event.
General settings
The following general settings define the general behavior of the function. These settings are static i.e.
it is not possible to change them by editing the setting group.
Table. 5.6.1 - 173. General settings of the function.
Name
Range Default
Description
I0 input selection
0: Not in
use
1: I01
2: I02
0: Not
in use
Selects the measurement input for the residual current. If the residual current is
measured with a separate CT, the residual current circuit can be monitored with
the CTS function as well. However, this does not apply to summing connections
(Holmgren, etc.). If the phase current CT is summed with I01 or I02, this selection
should be set to "Not in use".
I0 direction
0: Add
1:
Subtract
0: Add
Defines the polarity of residual current channel connection.
Compensate natural
unbalance
0: -
1:
Comp
0: -
When activated while the line is energized, the currently present calculated
residual current is compensated to 0.
Pick-up
The
I
set
and
I0
set
setting parameters control the current-dependent pick-up and activation of the
current transformer supervision function. They define the minimum and maximum allowed measured
current before action from the function. The function constantly calculates the ratio between the setting
values and the measured magnitude (
I
m
) for each of the three phases and for the selected residual
current input. The reset ratio of 97 % and 103% are built into the function and is always relative to the
I
set
value. The setting value is common for all measured amplitudes, and when the
I
m
exceeds the
I
set
value (in single, dual or all currents) it triggers the pick-up operation of the function.
A
AQ
Q-C215
-C215
Instruction manual
Version: 2.07
© Arcteq Relays Ltd
IM00040
227