CHAPTER 4 APPLIED OPERATION
E5CK
4--6
The change rate during the SP ramp is specified by the
“
SP ramp set value”
and
“
SP ramp time unit” parameters. At the
“
SP ramp set value” default
“
0”, the SP ramp function is disabled.
The set point changing in SP ramp can be monitored in the
“
Set point dur-
ing SP ramp” parameter (level 0 mode).
The limiters are invalid or cannot be set when any of the following condi-
tions occurs:
If the SP ramp function is enabled when the power is turned ON, and when
“
run” is switched to from
“
stop,” process value may reach the set point af-
ter SP ramp in the same way as when the set point is changed. In this case,
operation is carried out with the process value regarded as the set point
before the change was made.
The direction of the SP ramp changes according to the relationship be-
tween the process value and the set point.
SP
PV
SP
PV
PV < SP
PV > SP
Set point
SP ramp
SP ramp
Same change
rate
Set point
Power ON
Time
Time
Power ON
•
Execution of auto-tuning starts after the end of SP ramp.
•
When the controller is switched to the manual mode, the set point
changes continuously until SP ramp ends.
•
When an error occurs, the SP ramp function becomes invalid.
Symbol
Parameter Name: Mode
Description
MV upper limit
: Level 2
Manipulated variable restrictions
MV lower limit
: Level 2
Manipulated variable restrictions
MV change rate limit : Level 2
Manipulated variable restrictions
SP setting upper limit: Expansion
SP setting restrictions
SP setting lower limit : Expansion
SP setting restrictions
SP ramp set value
: Level 2
SP changing restrictions
SP ramp time unit
: Level 2
SP changing restrictions
F
Operation at start
F
Restrictions dur-
ing SP ramp
Parameters