Mitsubishi Electric FR-A820-00046 Instruction Manual page 750

(A) Application parameters
● Reverse action
When deviation X = (set point - measured value) is a plus value, the manipulated amount (output fre-
quency) is increased, and when the deviation is a minus value, the manipulated amount is decreased.
Set point
Fig. 5-265:
● Forward action
When deviation X = (set point - measured value) is a minus value, the manipulated amount (output
frequency) is increased, and when the deviation is a plus value, the manipulated amount is decreased.
Set point
Fig. 5-266:
Relationship between deviation and manipulated amount (output frequency)
PID action setting
Reverse action
Forward action
Tab. 5-223: Relationships between deviation and manipulated variable
5 - 548
[Heating]
+ X>0
Cold
Hot
X<0
-
Feedback signal
(measured value)
Heating
[Cooling]
X>0
+
Too cold
Hot
X<0
-
Feedback signal
(measured value)
Cooling
Deviation
Increase
Decrease
Measured value
Measured value
Decrease
Increase
Deviation
Deviation
Plus
Parameters
Set point
I002690E
Set point
I002691E
Minus