5.2 Control functions
5-15
Functions and
Operations
● Conditions for activation of disturbance overshoot adjustment
• If the deviation is greater than the "Disturbance judgement width"
after the PV is rectified to the "Disturbance rectification band", the
disturbance overshoot adjustment function activates.
• When the "Disturbance judgement width" is a positive value, distur-
bance overshoot adjustment will activate when a disturbance occurs
that makes the PV fall. When the "Disturbance judgement width" is a
negative value, disturbance overshoot adjustment will activate when
a disturbance occurs that makes the PV rise.
• Disturbance overshoot adjustment does not activate in the following
situations:
•
When "Disturbance rectification band" or "Disturbance judgement
width" is set to "0".
• When the SP is changed (when the SP change width exceeds
the "Disturbance rectification band")
• During AT
• During ON/OFF control (P = 0.00)
• During PD control (I = 0.00)
• The units for the "Disturbance rectification band" and "Disturbance
judgement width" settings are % FS. As such, if the input type is
K(1) -200.0 to 1300.0°C and you wish to set the "Disturbance
judgement width" to 15.0°C,
15.0°C/1500.0°C
× 100 = 1.00 %FS
hence "1.00" should be set.
Setting data Setting range Units
Default
value
Disturbance overshoot
adjustment enable
OFF: Disabled,
ON: Enabled
− OFF
Disturbance gain -1.00 to 1.00
− 0.65
Disturbance time constant 0.01 to 99.99
− 1.00
Disturbance rectification
band
0.000 to 9.999 %FS 0.000
Disturbance judgement
width
-99.99 to 99.99 %FS 0.00
do-b
1
0.000
l.adj
Disturbance rectification band
dojw
1
0.00
l.adj
Disturbance judgement width
Temper-
ature
Time
SP
Disturbance
rectification
band
Disturbance
judgement
width
Disturbance overshoot adjuster operates
Disturbance overshoot adjuster does not operate