IMO Precision Controls K7M-DR30S User Manual

Chapter 7 Usage of Various Functions
7-
౉ై
(c) Fig 2.10 shows examples of process control by forward and reverse actions, respectively.
Fig. 2-10 PV of forward / reverse action
f) Reference value
In general feedback control system shown as the Figure 2-10, the deviation value is obtained by the difference of
PV and SV. P, I, and D operations are performed based on this deviation value. However, each of P, I, and D
operations use different deviation values according to the characteristics of each control actions. The expression
of PID control is as following;
⎥
⎦
⎤
⎢
⎣
⎡
++=
∫
t
dt
dEd
TddssEi
Ti
EpKMV
0
)(
1
MV : Manipulate value
K: Proportional gain
Ti: Integral time
Td: Derivative time
Ep: Deviation value for proportional action
Ei: Deviation value for integral action
Ed: Deviation value for derivative action
The deviation values of P, I, and D action is described as following equations;
PVEd
PVSVEi
PVSVbEp
−=
−=
−×=
The b of the first equation is called as reference value. It can be varied according to the load disturbance of
measurement noise.
Fig. 2-11 Diagram of simple feedback system
Process
-1
+
SV
PV
MV
PID

IMO Precision Controls K7M-DR30S Specifications

General

Brand	IMO Precision Controls
Model	K7M-DR30S
Category	Controller
Language	English