Table. 5.5.3 - 143. Information displayed by the function.
Name
Range
Description
THD> LN
behaviour
1: On
2: Blocked
3: Test
4: Test/
Blocked
5: Off
Displays the mode of THD block.
This parameter is visible only when
Allow setting of individual LN mode is enabled in
General menu.
THD condition
0: Normal
1: Start
2: Alarm
3: Blocked
Displays status of the monitoring function.
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).
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 activation and reset
This function supports definite time delay (DT). The following table presents the setting parameters for
the function's time characteristics.
Table. 5.5.3 - 144. Settings for operating time characteristics.
Name
Range
Step
Default
Description
Phase THD alarm
delay
0.000…1800.000s 0.005s 10.000s Defines the delay for the alarm timer from the phase
currents' measured THD.
I01 THD alarm
delay
0.000…1800.000s 0.005s 10.000s Defines the delay for the alarm timer from the residual current
I01's measured THD.
I02 THD alarm
delay
0.000…1800.000s 0.005s 10.000s Defines the delay for the alarm timer from the residual current
I02's measured THD.
A
AQ
Q-T256
-T256
Instruction manual
Version: 2.06
222
© Arcteq Relays Ltd
IM00028
Summary of Contents for AQ-T256
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