Name
Range
Default
Description
Harmonic
selection
2
nd
harmonic
3
rd
harmonic
4
th
harmonic
5
th
harmonic
6
th
harmonic
7
th
harmonic
9
th
harmonic
11
th
harmonic
13
th
harmonic
15
th
harmonic
17
th
harmonic
19
th
harmonic
2
nd
harmonic
Selection of the monitored harmonic component.
Per unit or
relative
× I
n
Ih/IL
× I
n
Selection of the monitored harmonic mode. Either directly per unit x
I
n
or in relation to
the fundamental frequency magnitude.
Measurement
input
IL1/IL2/
IL3
I01
I02
IL1/IL2/
IL3
Selection of the measurement input (either phase current or residual current).
Each function stage provides these same settings. Multiple stages of the function can be set to operate
independently of each other.
Pick-up
The setting parameter
Ih
set
per unit or
Ih/IL (depending on the selected operating mode) controls the
pick-up of the Ih> function. This defines the maximum allowed measured current before action from the
function. The function constantly calculates the ratio between the
Ih
set
per unitor
Ih/IL and the
measured magnitude (
I
m
) for each of the three phases. The reset ratio of 97 % is built into the function
and is always relative to the
Ih
set
per unit or
Ih/ILvalue. The setting value is common for all measured
phases, and when the
I
m
exceeds the
I
set
value (in single, dual or all phases) it triggers the pick-up
operation of the function.
Table. 5.3.5 - 51. Pick-up settings.
Name
Range
Step
Default
Description
Ih
set
pu
0.05…2.00×I
n
0.01×I
n
0.20×I
n
Pick-up setting
(per unit monitoring)
Ih/IL
5.00…200.00%
0.01%
20.00%
Pick-up setting
(percentage monitoring)
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
61
Summary of Contents for AQ-T256
Page 1: ...AQ T256 Transformer protection IED Instruction manual...
Page 2: ......
