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
Default
Description
U0>
Measuring
now
0: No U0 avail!
1: U0Calc
2: U3 Input
3: U4 Input
-
0:
Select
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.
The blocking signal can also be tested in the commissioning phase by a software switch signal when
the relay's testing mode "Enable stage forcing" is activated (
General
→
Device).
The variables the user can set are binary signals from the system. The blocking signal needs to reach
the device minimum of 5 ms before the set operating delay has passed in order for the blocking to
activate in time.
Operating time characteristics for trip and reset
The operating timers’ behavior during a function can be set for TRIP signal and also for the release of
the function in case the pick-up element is reset before the trip time has been reached. There are three
basic operating modes available for the function:
• Instant operation: gives the TRIP signal with no additional time delay simultaneously with the
START signal.
A
AQ
Q-T215
-T215
Instruction manual
Version: 2.04
183
