xLadder user manual-V2.0.0.6

6.7.9 PID

Input/output

Operand

Data type

TBL

VB

Byte

LOOP

Constant(0 to 7)

Byte

According to the parameters in the TBL,PID

instruction performs the PID operation.Up to 8 PID

instructions can be used in the program,the value

of LOOP is the loop number of PID.PID loop number

can not be the same, otherwise it will cause

interference.Parameters in the TBL parameter

table includes : Process, set value, output, gain, sampling time,

integration time, differential time, the last time integral term, the last

time the amount of the process.

The parameter table contains 36 bytes:

Offset

Meaning

Format

Type

Explain

0

DINT

Input

0.0~1.0

PV

Process

n

quantity

4

DINT

Input

0.0~1.0

SP

Set point

n

8

Mn Output value

DINT

Input/Output

0.0~1.0

12

Kc gain

Input

Ratio constant

16

Ts Sampling time

DINT

Input

Ms Positive

20

DINT

Input

S

Positive

Integral time

T

I

24

DINT

Input

S

Positive

Differential time

T

D

28

DINT

Input/Output

Last time

Last time

MI

n 1 

integral value

integral value

32

DINT

Input/Output

Last time

PV

Last time

n 1 

process

process

128

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