Figure. 5.4.11 - 72. Selectable measurement magnitudes with 2LL+U4 VT connection (P-E voltages not available without
residual voltage).
P-P Voltages and P-E Voltages selections follow phase-to-neutral or phase-to-phase voltages in the
first three voltage channels (or two first voltage channels in the 2LL+U3+U4 mode).
U4 input selection
follows the voltage in Channel 4.
U3Input selection only follows the voltage in Channel 3 if the
2LL+U3+U4 mode is in use.
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. 5.4.11 - 116. General settings of the function.
Name
Range
Step Default
Description
U< LN
mode
1: On
2: Blocked
3: Test
4: Test/
Blocked
5: Off
-
0: On
Set mode of UV block.
This parameter is visible only when
Allow setting of individual LN mode is
enabled in
General menu.
Pick-up
The
U
set
setting parameter controls the pick-up of the U< function. This defines the minimum allowed
measured voltage before action from the function. The function constantly calculates the ratio
between the
U
set
and the measured magnitude (
U
m
) for each of the three voltages. The reset ratio of
103 % is built into the function and is always relative to the
U
set
value. The setting value is common for
all measured amplitudes, and when the
U
m
exceeds the
U
set
value (in single, dual or all voltages) it
triggers the pick-up operation of the function.
Table. 5.4.11 - 117. Pick-up settings.
Name
Description
Range
Step
Default
U
set
Pick-up setting
0.00…120.00%U
n
0.01%U
n
60%U
n
U Block
setting
Block setting. If set to zero, blocking is not in use. The operation is
explained in the next chapter.
0.00…100.00%U
n
0.01%U
n
10%U
n
A
AQ
Q-M257
-M257
Instruction manual
Version: 2.07
© Arcteq Relays Ltd
IM00021
143
Summary of Contents for AQ-M257
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