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 power value 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
This function supports definite time delay (DT). For detailed information on this delay types please refer
to the chapter "General properties of a protection function" and its section "Operating time
characteristics for trip and reset".
Events and registers
The underpower function (abbreviated "UPW" 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 function offers one (1) independent stage.
The events triggered by the function are recorded with a time stamp and with process data values.
Table. 5.3.17 - 148. Event codes.
Event number
Event channel
Event block name
Event code
Description
6464
101
UPW1
0
Start ON
6465
101
UPW1
1
Start OFF
6466
101
UPW1
2
Trip ON
6467
101
UPW1
3
Trip OFF
6468
101
UPW1
4
Block ON
6469
101
UPW1
5
Block 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.
A
AQ
Q-M215
-M215
Instruction manual
Version: 2.04
209