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 impedance values.
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.
Events and registers
The pole slip protection function (abbreviated "OOS" in event block names) generates events and
registers from the status changes in START, TRIP and BLOCKED. The user can select which event
messages are stored in the main event buffer: ON, OFF, or both.
The events triggered by the function are recorded with a time stamp and with process data values.
Table. 5.4.27 - 225. Event messages.
Event block name
Event names
OOS1
Poleslip Detection START ON
OOS1
Poleslip detection START OFF
OOS1
Poleslipt Trip ON
OOS1
Poleslip Trip OFF
OOS1
Poleslip detection BLOCKED ON
OOS1
Poleslip detection BLOCKED OFF
The function registers its operation into the last twelve (12) time-stamped registers. The register of the
function records the ON event process data for START, TRIP or BLOCKED. The table below
presents the structure of the function's register content.
Table. 5.4.27 - 226. Register content.
Date and time
Event
In blinder time
Used SG
dd.mm.yyyyhh:mm:ss.mss
Event name
Duration of reactance being between the blinders.
Setting group 1...8 active
5.4.28 Transformer thermal overload protection (TT>; 49T)
The transformer thermal overload protection function is used for monitoring and protecting thermal
capacity in power transformers.
A
AQ
Q-M257
-M257
Instruction manual
Version: 2.07
272
© Arcteq Relays Ltd
IM00021
Summary of Contents for AQ-M257
Page 1: ...AQ M257 Motor protection IED Instruction manual...
Page 2: ......
