Mitsubishi Electric MELSEC iQ-R Series - Page 1175

10 PID CONTROL INSTRUCTIONS
10.3 PID Control Instructions (Exact Differential)
1173
10
Processing details
• These instructions store the PID control data by the number of loops used that is set in the device number specified by (s)
and later altogether in the CPU module to enable PID control. ( Page 1151 PID control data)
• The PID control data are assigned as follows.
*1 m = (n-1)  10 + 2
• The number of device points used for PID control data setting is calculated by the following formula.
Number of device points = 2 + 10  n (n: number of loops used)
• Specify each data in binary.
• If the total number of device points for the number of loops used exceeds the last device number, an error occurs and no
processing is performed.
• If the PIDINIT(P) instruction is executed at two or more locations during a single scan, the setting value of the PIDINIT(P)
instruction executed nearest to the PIDCONT(P) instruction will be valid.
• Execute the PIDINIT(P) instruction before execution of the PIDCONT(P) instruction. PID control is disabled unless the
PIDINIT(P) instruction has been executed.
Operation error
Item PID control data
Common to all loops (s)+0 Number of loops used
(s)+1 Number of loops in one scan
For loop No.1 (10 words) (s)+2 Operational expression selection
(s)+3 Sampling period (T
S
)
(s)+4 Proportional constant (K
P
)
(s)+5 Integral constant (T
I
)
(s)+6 Derivative constant (T
D
)
(s)+7 Filter coefficient ()
(s)+8 Manipulated value lower limit (MVLL)
(s)+9 Manipulated value upper limit (MVHL)
(s)+10 Manipulated value variation rate limit (MVL)
(s)+11 Process value variation rate limit (PVL)

For loop No.n (10 words)
*1
(s)+(m+0) Operational expression selection
(s)+(m+1) Sampling period (T
S
)
(s)+(m+2) Proportional constant (K
P
)
(s)+(m+3) Integral constant (T
I
)
(s)+(m+4) Derivative constant (T
D
)
(s)+(m+5) Filter coefficient ()
(s)+(m+6) Manipulated value lower limit (MVLL)
(s)+(m+7) Manipulated value upper limit (MVHL)
(s)+(m+8) Manipulated value variation rate limit (MVL)
(s)+(m+9) Process value variation rate limit (PVL)
Error code
(SD0)
Description
3405H Out-of-range data is set in the device specified by (s).
• The value set for the PID control data is out of the setting range.
• (Number of loops used) < (number of execution loops in one scan)
• (Manipulated value upper limit) < (Manipulated value lower limit)