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It is high event. When the process value is higher than high limit, then the alarm or job
associated with this event is actuated.
5.2.3.7.1.2 L
It is low event. When the process value is lower than low limit, then the alarm or job associated
with this event is actuated.
5.2.3.7.1.3 HH
It is high high event. When the process value is higher than high high limit, then the alarm or job
associated with this event is actuated. This is another limit higher than high limit for double warning.
5.2.3.7.1.4 LL
It is low low event. When the process value is lower than low low limit, then the alarm or job
associated with this event is actuated. This is another limit lower than low limit for double warning.
5.2.3.7.1.5 Dev+
It is deviation+ event. This event will be triggered on the positive deviation of process value. The
job or alarm is activated when the process value is deviated by the value higher than set point from the
previous process value.
For example,
Set point =10
At 10.00.01 Hrs, Tag1=40
At 10.00.02 Hrs, Tag1 = 51
Then, job or alarm is activated
5.2.3.7.1.6 Dev-
It is deviation- event. This event will be triggered on the negative deviation of process value. The job or
alarm is activated when the process value is deviated by the value lower than set point from the previous
process value.
For example,
Set point =10
At 10.00.01 Hrs, Tag1=40
At 10.00.02 Hrs, Tag1 = 29
Then, job or alarm is activated.
5.2.3.7.1.7 Error
It is error event. This event will be activated when there is an error on the input of the channel.
5.2.3.7.2 Set point
Set point for the event.
5.2.3.7.2.1 Hysteresis
To avoid the alarm or event been activated too often, Hysteresis value can be defined for the
event trigger set point.
5.2.3.7.2.2 Holding time
To avoid the alarm or event been activated too often, the holding time can be defined for the
event trigger set point. In process sometimes SP is reached but it will go down immediately, this might due
to process instability. To avoid these kind of nuisance situations, the holding time can be used to see that
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