Indication Messages; Protection Indications - ABB REX 521 Operator's Manual

REX 521
3.3.
3.3.1.
22
Protection Relay
Operator's Manual
When entering single bit values, the bit to be edited may be shifted by pressing the
→
[ ] button when the cursor is located in the rightmost corner of the display. In that
way, the cursor does not have to be moved back and forth between the bit number
and the value during the setting period, thus simplifying the procedure.
For information about the meaning of each event, refer to Event List for REX 521
on the CD-ROM
Technical Descriptions of Functions
page 6).

Indication messages

There are two different kinds of indication messages:
• A text message together with a LED indication.
This type of messages are related to information from the protection functions
and information concerning the condition of the protection relay (self-
supervision).
• A text message without a LED indication.
This type of messages are related to condition monitoring, alarms and warnings
or help texts appearing when certain display operations are performed.
Indication messages have a certain priority. If different types of indications occur
simultaneously, the message with the highest priority appears on the display.
Priority order of the messages:
1. Internal fault, CBFP
2. Trip
3. Start, Block
4. Help messages
Indication messages may be cleared with the [C] button, until the display reverts to
the menu active before the events.
Help messages are displayed when certain operations are done. For example, when
resetting output relays, events and registered values by pressing the [C] and [E]
buttons for 5 s, a help text describing the operation is displayed at the same time.

Protection indications

When a protection function starts, the symbol of the protection function and the text
START are displayed. The corresponding yellow LED indicator is also lit. In case
of three-phase or two-phase protection functions, the faulted phases are displayed as
well.
green yellow red
Fig. 3.3.1.-1 Indication of start
If a started protection function is blocked, the name of the function and the text
BLOCK are displayed. Now, the yellow LED indicator is blinking.
3I> : START
L1 , L2 , L3
1MRS 751107-MUM
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