Monitoring; Self-Supervision (Irf) - ABB REJ 527 Technical Reference Manual

ABB Substation Automation
Products and Systems
4.1.4.
4.1.5.
1MRS750616-MUM
Technical Reference Manual
Table 13: Directional element
Feature
Setting range of basic angle ϕ
Operation sector
Operation sector accuracy
Threshold current for angle measurement
- pick-up/drop-off
Threshold voltage for angle measurement
- pick-up/drop-off

Monitoring

The function of the relay can be monitored with the help of three indicators on the
relay front panel: a green READY LED, a yellow START LED and a red TRIP
LED.
In addition, in case of an internal fault or an alarm from the protection stages, a text
message appears on the display.
The messages on the LCD have a certain priority order. If different types of
indications are activated simultaneously, the message with the highest priority
appears on the display.
The priority order of the messages:
1 Internal fault
2 Trip, CBFP
3 Start

Self-supervision (IRF)

The relay is provided with an extensive self-supervision system that continuously
supervises the software and the electronics of the relay. It handles run-time fault
situations and informs the user about an existing fault via a LED on the MMI and a
text message on the LCD.
When a fault is detected, the relay first tries to eliminate it by restarting. Only after
the fault is found to be permanent, the green READY indicator starts to blink and
the protection relay delivers a fault signal to the self-supervision output contact. All
other output contacts are blocked during an internal fault. Further, a fault indication
text appears on the LCD.
Fault indication has the highest priority on the MMI. None of the other MMI
indications can override the IRF indication. When the display panel has received a
fault indication, the indication text remains on the LCD. As long as the green LED
is blinking, the fault indication or the green LED can not be turned off. In case the
internal fault disappears, the fault indication text remains on the display. The green
Setting range
-90...0°
b
ϕ
±80° or ±88° with the additional
b
sector ϕ
±5°
0.50 / 0.30 %
0.48 / 0.36 %
REJ 527
0...90°
a
33