6. Function blocks
6.1 Manufacturer function blocks
6.1.4 Open-loop and closed-loop function blocks
6.1.4.1 DC - PID controller
General
easyE4 The base devices provide 32 PID controller function blocks
DC01...DC32.
Operating principle
A closed-loop control circuit with a PID controller consists of the following com-
ponents:
l
Setpoint (reference variable),
l
Actual value (controlled variable),
l
System deviation = (setpoint–actual value),
l
PID controller,
l
Control system (e.g. PTn system),
l
Disturbance variables.
The PID controller operates on the basis of the equation of the PID algorithm. According
to this, the manipulated variable Y(t) is the result of the calculation of the proportional
component, an integral component and a differential component.
PID controller equation:
Y(t) = YP(t) + YI(t) + YD(t)
Y(t)=
calculated manipulated variable with scan time t
YP(t)=
Value of the proportional component of the manip-
ulated variable with scan time t
YI(t) =
Value of the integral component of the manipulated
variable with scan time t
YD(t)=
Value of the differential component of the manip-
ulated variable with scan time t
Proportional component
The proportional component YP is the product of the gain (Kp) and the control difference
(e). The control difference is the difference between the setpoint (Xs) and the actual
value (Xi) at a specified scan time. The equation used by the device for the proportional
component is as follows:
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easyE4
11/18 MN050009 EN www.eaton.com
Summary of Contents for easyE4 series
Page 1: ...Manual 11 18 MN050009 EN easyE4 Manual...
Page 4: ......
Page 16: ...12 easyE4 11 18 MN050009 EN www eaton com...
Page 22: ...0 1 About this manual 18 easyE4 11 18 MN050009 EN www eaton com...
Page 169: ...easyE4 11 18 MN050009 EN www eaton com 165...
Page 490: ...7 System settings 7 16 Time and Date setting 486 easyE4 11 18 MN050009 EN www eaton com...
Page 520: ...9 easyE4 inside 9 7 NET network 516 easyE4 11 18 MN050009 EN www eaton com...
Page 570: ...11 Connection to other devices 11 6 E mail function 566 easyE4 11 18 MN050009 EN www eaton com...
Page 578: ...12 Faults 12 4 Functionality of the NET faulty 574 easyE4 11 18 MN050009 EN www eaton com...
Page 582: ...13 Maintenance 13 3 Storage transport and disposal 578 easyE4 11 18 MN050009 EN www eaton com...
Page 594: ...590 easyE4 11 18 MN050009 EN www eaton com...