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.
Table. 5.4.10 - 109. Information displayed by the function.
Name
Range
Step
Description
U> LN
behaviour
1: On
2: Blocked
3: Test
4: Test/Blocked
5: Off
-
Displays the mode of OV block.
This parameter is visible only when
Allow setting of individual LN
mode is enabled in General menu.
U< pick-
up setting
0.0...1 000 000.0V
0.1V
The primary voltage required for tripping. The displayed pick-up voltage
level depends on the pick-up setting and 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
A(B)
meas
/U
set
at the
moment
0.00...1250.00U
m
/U
set
0.01U
m
/U
set
The ratio between U
A
or U
AB
voltage and the pick-up value.
U
B(c)
meas
/U
set
at the
moment
0.00...1250.00U
m
/U
set
0.01U
m
/U
set
The ratio between U
B
or U
BC
voltage and the pick-up value.
U
C(A)
meas
/U
set
at the
moment
0.00...1250.00U
m
/U
set
0.01U
m
/U
set
The ratio between U
C
or U
CA
voltage and the pick-up value.
U
meas
/U
set
at the
moment
0.00...1250.00U
m
/U
set
0.01U
m
/U
set
The ratio between the measured 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-M257
-M257
Instruction manual
Version: 2.07
© Arcteq Relays Ltd
IM00021
137
Summary of Contents for AQ-M257
Page 1: ...AQ M257 Motor protection IED Instruction manual...
Page 2: ......
