11 PROCESS CONTROL INSTRUCTIONS
11.1 Overview
1181
11
11
PROCESS CONTROL INSTRUCTIONS
When a process control program is created, using process control function blocks is recommended
Process control function blocks have features as follows.
• A process control program can be easily created by placing and connecting FB elements.
• Since the initial value of the function block can be set in the "FB Property" window of the engineering tool,
the program for the initial value setting is not required.
• An operation constant can be input to a label indicating a tag name without being conscious of address of a
device.
• The operating status of a tag FB can be checked and controlled by accessing the tag data from the
faceplate of an engineering tool.
For details on the process control function blocks, refer to the following.
MELSEC iQ-R Programming Manual (Process Control Function Blocks)
11.1
Overview
This section describes the loop type that can be configured by process control instructions, data configurations of the
instructions, instruction execution methods, and precautions.
Basic loop types
The following table summarizes basic loop types configured by combinations of process control instructions.
Loop type
Configuration
Application
Two-degree-of-freedom
PID control (S2PID)
Used for general PID control (two degrees of freedom). (Speed
type)
PID operation is performed every control cycle.
PID control (SPID)
Used for general PID control. (Speed type)
PID operation is performed every control cycle.
PIDP control (SPIDP)
Used for general PID control. (Position type)
PID operation is performed every control cycle.
Sample PI control (SSPI)
Used for processes which involve much dead time.
PI control is executed only for the control execution time every
control cycle, and later output is held constant.
I-PD control (SIPD)
Used to make a slow response so as not to give a shock to the
operation terminal and process when the set value is changed.
S.IN
INPUT
OUTPUT
S.PHPL
S.2PID
S.OUT1
SET
PV
SV
MV
S.IN
INPUT
OUTPUT
S.PHPL
S.2PID
S.DUTY
SET
PV
SV
MV
S.IN
INPUT
OUTPUT
S.PHPL
S.PID
S.OUT1
SET
PV
SV
MV
S.IN
INPUT
OUTPUT
S.PHPL
S.PID
S.DUTY
SET
PV
SV
MV
S.IN
INPUT
OUTPUT
S.PHPL
S.PIDP
SET
PV
SV
MV
S.IN
INPUT
OUTPUT
S.PHPL
S.SPI
S.OUT1
SET
PV
SV
MV
S.IN
INPUT
OUTPUT
S.PHPL
S.IPD
S.OUT1
SET
PV
SV
MV
Summary of Contents for MELSEC iQ-R Series
Page 1: ...MELSEC iQ R Programming Manual Instructions Standard Functions Function Blocks ...
Page 2: ......
Page 24: ...22 INDEX 2092 INSTRUCTION INDEX 2093 REVISIONS 2104 WARRANTY 2105 TRADEMARKS 2106 ...
Page 34: ...32 MEMO ...
Page 35: ...33 PART 1 PART 1 OVERVIEW This part consists of the following chapter 1 OVERVIEW ...
Page 68: ...66 1 OVERVIEW 1 5 Precautions on Programming MEMO ...
Page 1448: ...1446 14 REDUNDANT SYSTEM INSTRUCTIONS 14 2 Disabling Enabling System Switching MEMO ...
Page 1972: ...1970 33 TIME DATA TYPE FUNCTIONS 33 4 Division MEMO ...
Page 2067: ...APPX Appendix 5 PID Control Program Examples 2065 A 252 Set PID control data for loop 2 ...
Page 2109: ......