Omron SYSMAC CVM1 Series Operation Manual page 337

PID and Related Instructions
Item
Input range
Output range
Integral and
derivative unit
Manipulated
variable output
lower limit
Manipulated
variable output
upper limit
PID CONTROL Action
The number of input data bits.
The number of output data bits. {The number
of output bits is automatically the same as the
number of input bits.)
Determines the unit for expressing the integral
and derivative constants.
The lower limit for when the manipulated
variable output limit is enabled.
The upper limit for when the manipulated
variable output limit is enabled.
Note 1. When the unit is designated as 1, the range is from 1 to 8,191 times the peri-
od. When the unit is designated as 9, the range is from 0.1 to 819.1 s. When
9 is designated, set the integral and derivative times to within a range of 1 to
8,191 times the sampling period.
2. Setting the 2-PID parameter (α) to 000 yields 0.65, the normal value.
3. When the manipulated variable output limit control is enabled (i.e., set to
"1"), set the values as follows:
0000 x lower limit x upper limit x output range maximum value
Execution Condition OFF
All data that has been set is retained. When the execution condition is OFF, the
manipulated variable can be written to the output word (D) to achieve manual
control.
Rising Edge of the Execution Condition
The work area is initialized based on the PID parameters that have been set and
the PID control action is begin. Sudden and radical changes in the manipulated
variable output are not made when starting action to avoid adverse affect on the
controlled system (bumpless operation).
When PID parameters are changed, they first become valid when the execution
condition changes from OFF to ON.
Execution Condition ON
The PID action is executed at the intervals based on the sampling period, ac-
cording to the PID parameters that have been set.
Sampling Period and PID Execution Timing
The sampling period is the time interval to retrieve the measurement data for
carrying out a PID action. PID(270), however, is executed according to CPU
cycle, so there may be cases where the sampling period is exceeded. In such
cases, the time interval until the next sampling is reduced.
Contents
Section 5-24
Setting range
0: 8 bits 5: 13 bits
1: 9 bits 1: 9 bits 6: 14 bits 6: 14 bits
2: 10 bits 7: 15 bits
3: 11 bits 8: 16 bits
4: 12 bits
1: Sampling period multiple
9: Time (unit: 100 ms)
0000 to FFFF (binary)
(See note 3.)
0000 to FFFF (binary)
(See note 3.)
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