1.Non-Latched Alarm; 2.Latched Alarm, Steady Led - ABB RET 54 Series Technical Reference Manual, General

RET 54_
5.1.16.1.
5.1.16.2.
88
Transformer Terminal
Technical Reference Manual, General
The alarm channels are seen as function blocks in the transformer terminal
configuration:
Alarm channel Function block
Alarm channel 1 MMIALARM1
Alarm channel 2 MMIALARM2
Alarm channel 3 MMIALARM3
Alarm channel 4 MMIALARM4
Alarm channel 5 MMIALARM5
Alarm channel 6 MMIALARM6
Alarm channel 7 MMIALARM7
Alarm channel 8 MMIALARM8
Non-latched alarm
In a non-latched mode, the ON signal switches between ON and OFF state texts and
the corresponding LED colors. Alarm acknowledgement (ACK) clears the last time
stamp line of the alarm view, but leaves the corresponding alarm LED state
unchanged. An event is generated on the rising and falling edge of the ON signal and
by acknowledgement.
Fig. 5.1.16.1.-1 Example of a non-latched alarm
Latched alarm, steady LED
Latched, steady alarms can be acknowledged only when the ON signal is inactive.
The time stamp of the first alarm is recorded. Successful acknowledgement clears
the time stamp line of the alarm view and the corresponding alarm LED. An event
is generated on the rising and falling edge of the ON signal and by
acknowledgement.
1MRS755225
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