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10 pid control (pr. 88 to pr. 94 ), Age 117 – MITSUBISHI ELECTRIC FR-S520E User Manual

Page 127

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117

Operation selection function parameters

2

F

UNCT

IO

NS

2.10.10 PID control (Pr. 88

to Pr. 94

)


(1) Basic PID control configuration

(2) PID action overview

The inverter can be used to exercise process control, e.g. flow rate, air volume
or pressure.

The voltage input signal (0 to +5V or 0 to +10V) or Pr. 93 setting is used as a
set point and the 4 to 20mADC current input signal used as a feedback value
to constitute a feedback system for PID control.

POINT

Made valid by turning on the X14 signal. Use Pr. 60 to Pr. 63 (input terminal function
selection) to make assignment.

Parameter

Name

Factory

Setting

Setting Range

Remarks

88

PID action selection

20

20, 21

Setting is enabled
when Pr. 30 = "1"

89

PID proportional band

100%

0.1 to 999%, - - -

90

PID integral time

1s

0.1 to 999s, - - -

91

PID upper limit

- - -

0 to 100%, - - -

92

PID lower limit

- - -

0 to 100%, - - -

93

PID action set point for PU
operation

0%

0 to 100%

94

PID differential time

- - -

0.01 to 10s, - - -

1) PI action

A combination of proportional control
action (P) and integral control action (I)
for providing a manipulated variable in
response to deviation and changes
with time.

[Operation example for stepped
changes of measured value]

REMARKS

PI action is the sum of P and I actions.

+-

IM

Kp: Proportion constant Ti: Integral time S: Operator Td: Differential time

Set point

Manipulated

variable

Motor

Feedback signal (Measured value)

Inverter circuit :

Ti S

1

1+

+Td S

Kp

PID operation

Terminal 4

Pr. 93 or Treminal 2

Deviation Set point

Measured value

Time

Time

Time

PI action

I action

P action

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