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Warning and alarm messages
There is a clear distinction between alarms and
warnings. In the case of an alarm, the FC motor / VLT
2800 will enter a fault condition. After the cause for
the alarm has been cleared, the master will have to
acknowledge the alarm message for the FC motor /
VLT 2800 to start operating again. A warning, on the
other hand may come when a warning condition
appears, and disappear when conditions return to
normal without interfering with the process.
Warnings
Any warning within the FC motor / VLT 2800 is
represented by a single bit within a warning word. A
warning word is always an active parameter. Bit
status FALSE [0] means no warning, while bit status
TRUE [1] means warning.
Any bit change in the warning word will result in a
Spontaneous message being issued.
In addition to the warning word message the master
will also be notified through a change of bit 7 in the
Status Word.
Alarms
Following an Alarm message the FC motor / VLT
2800 will enter Fault condition. Only after the fault has
been alleviated and the master has acknowledged the
alarm message by setting bit 7 in the Control word,
can the FC motor /VLT 2800 resume operation.
Any alarm within the FC motor / VLT 2800 is
represented by a single bit within an alarm word. An
alarm word is always an action parameter. Bit status
FALSE [0] means no fault, while bit status TRUE [1]
means fault.
Any bit change in the alarm word will result in a
Spontaneous message being issued.
MG.90.A2.02 – VLT is a registered Danfoss trademark
FCM 300 PROFIBUS / VLT 2800 PROFIBUS
Spontaneous messages
If a fault or warning condition should occur, the FC
motor / VLT 2800 will, if the proper communicative
relationship has been established, issue a
Spontaneous message to communication partners.
Instead of responding to the master's request, the FC
motor / VLT 2800 will exchange the requested
response with the alarm or the warning message.
Warnings and alarms will trigger a Spontaneous
message. The same is true with any change to an
active parameter.
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