Using the SP Ramp Function to Limit the SP Change Rate
Parameters
Symbol
ol-h
ol-l
sl-h
sl-l
sprt
spru
alsp
Operation at Startup
Restrictions during
SP Ramp Operation
Parameter: level
MV Upper Limit: Adjustment level
MV Lower Limit: Adjustment level
Set Point Upper Limit: Initial setting level
Set Point Lower Limit: Initial setting level
SP Ramp Set Value: Adjustment level
SP Ramp Time Unit: Advanced function setting level
Alarm SP Selection: Advanced function setting level
If the SP ramp function is enabled when the Controller is turned ON or when
switching from STOP to RUN mode, the process value reaches the set point
using the SP ramp function in the same way as when the set point is changed.
In this case, operation is carried out with the process value treated as the set
point before the change was made. The direction of the SP ramp changes
according to the relationship between the process value and the set point.
PV < SP
SP
SP ramp
Set point
PV
Power ON
• Execution of auto-tuning starts after the end of the SP ramp.
• When control is stopped or an error occurs, the SP ramp function is dis-
abled.
Description
To limit the manipulated variable
To limit the manipulated variable
To limit the SP setting
To limit the SP setting
To limit the SP rate of change
Unit for setting the SP
Alarm SP selection
PV > SP
SP
SP ramp
PV
Set point
Time
Power ON
Section 4-7
Same rate
of change
Time
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