Instruction manual

137
4
PARAMETERS
4) Reverse action
Increases the manipulated variable (output frequency) if deviation X = (set point
- process value) is positive, and decreases the manipulated variable if deviation
is negative.
5) Forward action
Increases the manipulated variable (output frequency) if deviation X = (set point
- process value) is negative, and decreases the manipulated variable if
deviation is positive.
Relationships between deviation and manipulated variable (output frequency)
Deviation
Positive Negative
Reverse
action

Forward
action

Set point
X>0
X<0
Feedback signal
(Process value)
+
−
[Heating]
Deviation
Process value
Set poin
t
Cold → up
Hot
→
down
+
−
[Cooling]
Set point
X>0
X<0
Feedback signal
(Process value)
Set point
Process value
Deviation
Too cold
→
down
Hot
→
up
M4500E.book 137 ページ ２００５年２月２２日 火曜日 午後５時７分