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6 ACTUAL VALUES
6.6 TARGET MESSAGES
Target messages are displayed when any protection, monitoring or self-test target is activated. The messages
contain information about the type of the active target(s), and are displayed in a queue that is independent of
both the setpoint and actual value message structures.
When any target is active, the MESSAGE indicator will light, and the first message in the queue is displayed
automatically. The target message queue may be scrolled through by pressing
If no key is pressed, the next target message in the queue will be displayed after a delay of four seconds. This
process repeats, continuously cycling through the queue of target messages.
As long as there is at least one message in the queue, the MESSAGE indicator will remain lit. Pressing any
key other than
will return the display to the setpoint or actual value message that was previously dis-
N EXT
played. The
key may be pressed any time the MESSAGE indicator is lit, to redisplay the target message
N E XT
queue.
If
is pressed when no target messages are in the queue, all front-panel LEDs will light and the flash
N E XT
message
SS NO ACTIVE TARGETS
SS (TESTING LEDS)
will appear. A typical active target message looks like this,
S LATCHED: a
S Percent Differentl
and consists of three components which are arranged thus:
S <STATUS>: <PHASE>
S <CAUSE>
<STATUS> will be one of PICKUP , OPERATE or LATCHED .
•
PICKUP: Indicates that the fault condition that is required to activate the protection element has been
detected by the 745 but has not persisted for a sufficiently long time to cause the relay to activate its pro-
tection function.
•
OPERATE: Indicates that the protection element has been activated.
•
LATCHED: Indicates that the protection element is (or was) activated. This display will remain even if the
conditions that caused the element to activate are removed.
•
<PHASE> are the phase(s) that are associated with the element (where applicable).
Messages for LATCHED targets remain in the queue until the relay is reset. Messages for PICKUP and OPERATE
targets remain in the queue as long as the condition causing the target to be active is present.
In addition, messages for LATCHED targets will automatically be deleted if an entire week passes without any
changes to the state of the target messages but the conditions that caused the LATCHED messages to be dis-
played originally are no longer present.
GE Power Management
745 Transformer Management Relay
6.6 TARGET MESSAGES
6.6.1 DESCRIPTION
.
N EXT
6-19
6
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