Mitsubishi Electric FR-D720-0.2K-G Instruction Manual page 227

Special operation and speed control
(10) Calibration example
A detector of 4mA at 0C and 20mA at 50C is used to adjust the room temperature to 25C under PID control.
The set point is given to across drive unit terminals 2 and 5 (0 to 5V).
Start
Determination of set point
Determine the set point of what
is desired to be adjusted.
Conversion of set point into %
Calculate the ratio of the set
point to the detector output.
Make calibration.
Setting of set point
Input a voltage across terminals 2
and 5 according to the set value %.
Operation
Set the proportional band (Pr. 129 )
to a slightly larger value, the
integral time (Pr. 130 ) to a slightly
longer time, and the differential
time (Pr. 134 ) to "9999" (no
function), and turn ON the start
signal.
Is the set point stable?
Parameter adjustment
To stabilize the measured value,
change the proportional band (Pr.
129 ) to a larger value, the integral
time (Pr. 130 ) to a slightly longer
time, and the differential time (Pr.
134 ) to a slightly shorter time.
Adjustment end
* When calibration is required
Using calibration Pr. 902 and Pr. 903 (terminal 2) or Pr. 904 and Pr. 905 (terminal 4), calibrate the detector output and target setting
input.
(For the details of Pr. 902 to Pr. 905, refer to page 152.)
However, use Pr. 934 and Pr. 935 instead of Pr. 904 and Pr. 905 when both of C42 (Pr. 934) and C44 (Pr. 935)  "9999".
(For the details of Pr. 934 and Pr. 935, refer to page 225.)
Make calibration in the PU mode during an drive unit stop.
224
Set the room temperature to 25 C.
Set Pr. 128 and turn ON the X14 signal to enable PID control.
Detector specifications
When 0
on the assumption that 4mA is 0% and 20mA is 100%.
(Converting set point to % is unnecessary when both of C42 (Pr. 934) and
C44 (Pr. 935)
Make the following calibration* when the target setting input (0 to 5V) and
detector output (4 to 20mA) must be calibrated.
When the set point is 50%
As the terminal 2 specifications are 0%
to the terminal 2 for the set point of 50%.
(When both of C42 (Pr. 934) and C44 (Pr. 935) are set other than "9999", set
"25" as the set point (no % conversion) directly to the Pr. 133.)
When the parameter unit is used for operation, input the set point (0 to
100%) in Pr. 133.
When performing operation, first set the proportional band (Pr. 129 ) to a
slightly larger value, the integral time (Pr. 130 ) to a slightly longer time,
and the differential time (Pr. 134 ) to "9999" (no function), and while looking
at the system operation, decrease the proportional band (Pr. 129 ) and
increase the integral time (Pr. 130 ). For slow response system where a
deadband exists, differential control (Pr. 134 ) should be turned ON and
increased slowly.
Yes
No
Parameter optimization
While the measured value is stable
throughout the operation status, the
proportional band (Pr. 129 ) may be
decreased, the integral time (Pr. 130 )
decreased, and the differential time
(Pr. 134 ) increased.
4mA and 50 20mA are used, the set point 25
"9999".)
0V and 100%
is 50%
5V, input 2.5V