Pick-up
The
U
set
setting parameter controls the pick-up of the U0> function. This defines the maximum 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 neutral voltage. The reset ratio of 97 % 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 it triggers the pick-up operation of the function.
Table. 5.4.9 - 108. Pick-up settings.
Name
Description
Range
Step
Default
Pick-up setting U0set>
Pick-up setting
1.00…99.00%U
n
0.01%U
n
20.00%U
n
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.
Read-only parameters
The relay's
Info page displays useful, real-time information on the state of the protection function. It is
accessed either through the relay's HMI display, or through the setting tool software when it is
connected to the relay and its Live Edit mode is active.
Name
Range
Step
Description
U0>
Measuring
now
0: No U0 avail!
1: U0Calc
2: U3 Input
3: U4 Input
-
Displays which voltage channel is used by the function. If no voltage channel
has been selected the function defaults to calculated residual voltage if line-
to-neutral voltages have been connected to device. If no channel is set to
"U0" mode and line-to-line voltages are connected, no residual voltage is
available and "No U0 avail!" will be displayed.
U0> Pick-
up setting
0.0...1 000 000.0V
0.1V
Primary voltage required for tripping. The displayed pick-up voltage level
depends on the chosen U0 measurement input selection, on the pick-up
settings and on the voltage transformer settings.
Expected
operating
time
0.000...1800.000s
0.005s
Displays the expected operating time when a fault occurs. When IDMT mode
is used, the expected operating time depends on the measured voltage
value. If the measured voltage changes during a fault, the expected operating
time changes accordingly.
Time
remaining
to trip
-1800.000...1800.000s 0.005s When the function has detected a fault and counts down time towards a trip,
this displays how much time is left before tripping occurs.
U
meas
/U
set
at the
moment
0.00...1250.00
0.01
The ratio between the measured or calculated neutral voltage and the pick-
up value.
Function blocking
The block signal is checked in the beginning of each program cycle. The blocking signal is received
from the blocking matrix in the function's dedicated input. If the blocking signal is not activated when
the pick-up element activates, a START signal is generated and the function proceeds to the time
characteristics calculation.
If the blocking signal is active when the pick-up element activates, a BLOCKED signal is generated and
the function does not process the situation further. If the START function has been activated before the
blocking signal, it resets and the release time characteristics are processed similarly to when the pick-
up signal is reset.
The blocking of the function causes an HMI display event and a time-stamped blocking event with
information of the startup voltage values and its fault type to be issued.
A
AQ
Q-C215
-C215
Instruction manual
Version: 2.07
152
© Arcteq Relays Ltd
IM00040