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.
Operating time characteristics for trip and reset
This function supports definite time delay (DT). For detailed information on this delay type please refer
to the chapter "General properties of a protection function" and its section "Operating time
characteristics for trip and reset".
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. 5.4.21 - 181. Information displayed by the function.
Name
Range
Step
Description
Im> LN
behaviour
1: On
2: Blocked
3: Test
4: Test/Blocked
5: Off
-
Displays the mode of MJP block.
This parameter is visible only when
Allow setting of individual LN mode is
enabled in
General menu.
Im>
condition
0: Normal
1: Start
2: Trip
3: Blocked
-
Displays status of the protection function.
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 highest phase
current value. If the measured current 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.
I
meas
/I
set
at the
moment
0.00...1250.00
0.01
The ratio between the highest measured phase current 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 current 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).
A
AQ
Q-M257
-M257
Instruction manual
Version: 2.07
216
© Arcteq Relays Ltd
IM00021
Summary of Contents for AQ-M257
Page 1: ...AQ M257 Motor protection IED Instruction manual...
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