Table. 5.3.4 - 43. Measurement inputs of the I2> function.
Signal
Description
Time base
I1
Positive sequence current magnitude
5 ms
I2
Negative sequence current magnitude
5 ms
IZ
Zero sequence current magnitude
5 ms
I1 ANG
Positive sequence current angle
5 ms
I2 ANG
Negative sequence current angle
5 ms
IZ ANG
Zero sequence current angle
5 ms
IL1RMS
Phase L1 (A) measured RMS current
5 ms
IL2RMS
Phase L2 (B) measured RMS current
5 ms
IL3RMS
Phase L3 (C) measured RMS current
5 ms
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. 5.3.4 - 44. General settings of the function.
Name
Range Default
Description
I2> LN mode
1: On
2:
Blocked
3: Test
4: Test/
Blocked
5: Off
1: On
Set mode of CUB block.
This parameter is visible only when
Allow setting of individual LN mode is enabled in
General menu.
Measurement
side
1: Side
1
2: Side
2
1: Side
1
Defines which current measurement module is used by the function. Visible if the unit
has more than one current measurement module.
Measured
magnitude
1: I2pu
2: I2/I1
1: I2pu
Defines whether the ratio between the positive and the negative sequence currents are
supervised or whether only the negative sequence is used in detecting unbalance.
Pick-up
The setting parameters
I2
set
and I2/I1
set
control the the pick-up of the I2> function. They define the
maximum allowed measured negative sequence current or the negative/positive sequence current ratio
before action from the function. The function constantly calculates the ratio between the
I
set
and the
measured magnitude (
I
m
). The reset ratio of 97 % is built into the function and is always relative to the
I
xset
value. The reset ratio is the same for both modes.
Table. 5.3.4 - 45. Pick-up settings.
Name
Description
Range
Step
Default
I2set
Pick-up setting for I2 mode.
0.01…40.00×I
n
0.01×I
n
0.2×I
n
I2/I1set
Pick-up setting for I2/I1 mode
1…200%
0.01%
20%
The pick-up activation of the function is not directly equal to the START signal generation of the
function. The START signal is allowed if the blocking condition is not active.
A
AQ
Q-T256
-T256
Instruction manual
Version: 2.06
© Arcteq Relays Ltd
IM00028
53
Summary of Contents for AQ-T256
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