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Chapter 4. Functions
Operation type
Operation
type
setting
Direct action
Reverse action
PV change rate
high limit
55
Sets the change rate high or low limit for the event main setting. Measures the PV
for each sampling cycle (in seconds) set in the event subsetting, and compares the
change in the PV with the change rate high limit or low limit to determine whether to
turn the event on or off.
Event is turned ON and OFF on a sampling cycle basis. Change in the PV between
sampling cycles is ignored. The event hysteresis and event direct/reverse settings are
disabled. The event ON delay and event OFF delay can be combined.
When event setting value > 0 (normally, high limit event is used)
Sampling cycle
PV change rate
high limit event
operation
OFF
ON (increase alarm) OFF
PV change rate
low limit event
operation
ON
OFF
ON
(1)
(2)
(3)
(4)
sampling
time
Event main
setting
Event main setting
Event main setting
PV
When event setting value < 0 (normally, low limit event is used)
Sampling cycle
PV change rate
high limit event
operation
ON (decrease alarm) OFF
PV change rate
low limit event
operation
ON
OFF
ON
time
Event main setting
Event main setting
Event main setting
PV
(1)
(2)
(3)
(4)
sampling
PV change rate
low limit
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