Omron CPM1 - PROGRAMING MANUAL 02-2001 Programming Manual page 445

Data Control Instructions
Description
Word Bits Parameter name
P1 00 to 15 Set value (SV).
P1+1 00 to 15 Proportional band
width.
P1+2 00 to 15 Integral time (Tik)/
sampling period ( )
P1+3 00 to 15 Derivative time
(Tdk)/sampling peri-
od ( )
P1+4 00 to 15 Sampling period ( )
P1+5 00 to 03 Operation specifier
04 to 15 Input filter coefficient
( )
P1+6 00 to 03 Output range
08 to 15 Input range
P1+7 to 00 to 15 Work area
P1+32
! Caution
PID(––) performs PID control based on the parameters specified in P1 through
P1+6.
When the execution condition OFF, PID(––) is not executed. When the execu-
tion condition is ON, PID(––) carries out PID control according to the designated
parameters. It takes the specified input range of binary data from the contents of
IW and carries out the PID action according to the parameters that are set. The
result is then stored as the manipulated variable in OW.
The following table shows the function of the parameter words.
This is the target value for PID control. It can be set to any binary number
with the number of bits set by the input range parameter.
This parameter specifies the proportional band width/input range ratio from
0.1% to 999.9%. It must be BCD from 0001 to 9999.
Sets the strength of integral action. Increasing this value strengthens the
integral action. It must be BCD from 0001 to 8191, or 9999. A setting of
9999 disables integral control.
Set the integral time divided by the sampling time.
Sets the strength of derivative action. Increasing this value strengthens the
derivative action. It must be BCD from 0001 to 8191, or 0000.
(A setting of 0000 disables derivative control.)
Set the derivative time divided by the sampling time.
Sets the interval between samplings of the input data. It must be BCD from
0001 to 1023. The period will be from 0.1 to 102.3 s
Sets reverse or normal operation. Set to 0 to specify reverse operation or
1 to specify normal operation.
Determines the strength of the input filter. The lower the coefficient, the
weaker the filter.
This setting must be BCD from 100 to 199, or 000. A setting of 000 sets
the default value (0.65) and a setting of 100 to 199 sets the coefficient
from 0.00 to 0.99.
Determines the number of bits of output data. This setting must be be-
tween 0 and 8, which sets the output range between 8 and 16 bits.
Determines the number of bits of input data. This setting must be between
00 and 08, which sets the input range between 8 and 16 bits.
Do not use.
(Used by the system.)
Changes made to the parameters will not be effective until the execution condi-
tion for PID(––) goes from OFF to ON.
Note Do not use PID(––) in the following situations; it may not be executed properly.
In interrupt programs
In subroutine programs
In interlocked program sections (between IL and ILC)
In jump program sections (between JMP and JME)
In step ladder program section (created with STEP)
When the execution condition is ON, PID(––) performs the PID calculation on
the input data when the sampling period has elapsed. The sampling period is the
time that must pass before input data is read for processing.
Function/Setting range
Section 7-18
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