User Manual

Alarm management
Alarm response of the function blocks
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Binary Output
The alarm handling process in the binary output function block is essentially different from that of the
binary input and binary value blocks.
● An OFFNORMAL alarm occurs when the current values of the variables [PrVal] and [FbVal] differ from
each other for a time period at least equivalent to the delay time specified in [TiMonDvn], [TiMonOff]
or [TiMonOn].
● An existing OFFNORMAL alarm will disappear when the current [PrVal] und [FbVal] are again identical
and remain so for a period at least equivalent to the time specified in the variable [TiMonDvn].
● A FAULT alarm is generated when the [Rlb] property of the function block assumes any value other
than NO_FAULT_DETECTED. In particular, this is the case when the [Rlb] property changes from a
value not equal to NO_FAULT_DETECTED to another value not equal to NO_FAULT_DETECTED.
In the case of the binary output, [Rlb] errors may originate both from the [PrVal] (or associated physical
output) and from the [FbVal] (or associated physical input).
● A FAULT alarm will disappear as soon as the variable [Rlb] changes from a value not equal to
NO_FAULT_DETECTED back to the value NO_FAULT_DETECTED.
Command Control
An OFFNORMAL alarm is generated:
● A monitored, referenced object is not enabled
● A referenced object cannot be enabled
A FAULT alarm is generated when: