Mitsubishi Electric fr-e700 series, Instruction Manual

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Special operation Parameter
6 - 302
Calibration example
Example
쑴
A detector of 4 mA at 0 °C and 20 mA at 50 °C is used to adjust the room temperature to 25 °C
under PID control. The set point is given to across inverter terminals 2-5 (0 to 5 V).
I001237E
Fig. 6-155: Calibration example
Set the room temperature to 25 °C
Set Pr. 128 to "20" or "21", to enable PID control.
Start
Determination of set point
Conversion of set point into %
Determine the set point of what is
desired to be adjusted.
Calculate the ratio of the set point to
the detector output.
Detector specifications
When 0 °C 4 mA and 50 °C 20 mA are used, the set point
25 °C is 50% on the assumption that 4 mA is 0% and 20 mA is
100%.
Make calibration. Make the calibration as described in the following section when
the target setting input (0 to 5 V) and detector output (4 to
20 mA) must be calibrated.
Setting of set point
Input a voltage across terminals 2-5
according to the set value %.
When the set point is 50%
As the terminal 2 specifications are 0% 0 V and 100% 5 V, input
2.5 V to the terminal 2 for the set point of 50%.
Operation
To stabilize the measured value, change
the proportional band (Pr. 129) to a larg-
er value, the integral time (Pr. 130) to a
slightly longer time.
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, de-
crease the proportional band (Pr. 129) and increase the integral
time (Pr. 130).
Is the set point stable?
Yes
No
Parameter adjustment
Parameter optimization
While the measured value is stable
throughout the operation status, the pro-
portional band (Pr. 129) an the integral
time (Pr. 130) may be decreased.
Adjustment end
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.