Chapter 4 Explanation of Functions

4.2.23 PID function

The PID function allows you to use the inverter for the process control on fluid flow, airflow, and pressure.

To enable this function, specify "01 lenabled" or "02 inverted data output enabled" for function "A071".

You can disable the PID function with an external signal during the PID operation. For this purpose, assign function "23" (PID terminal: disabling PID operation) to an intelligent input terminal. Turning the PID terminal on disables the PID function and makes the inverter perform the normal output.

With the PID function, you can limit the PID output according to various conditions.

Refer to maximum frequency (4.2.10), frequency limiter (4.2.20), PID rariation range (A078).

Related code

A001: Frequency source setting

A005: [AT] selection

A006: [O2] selection

A071: PID Function Enable

A072: PID proportional gain

A073: PID integral time constant

A074: PID derivative gain

A075: PV scale conversion

A076: PV source setting

A077: Output of inverted PID deviation

A078: PID variation range

A079: PID feed forward selection

d004: Process variable (PV), PID feedback monitoring

C001 to C008: Terminal [1] to [8] functions

C021 to C025: Terminal [11] to [15] functions

C044: PID deviation level setting

C052: Off level of feedback comparison signal

C053: Onlevel of feedback comparison signal

Item

Function code

Data or range of data

Description

PID Function Enable

A071

00

Disabling the PID operation

01

Enabling the PID operation

 

 

02

Enabling inverted-data output

PID proportional gain

A072

0.2 to 5.0

Proportional gain

PID integral time constant

A073

0.0 to 3600.(s)

Integrated gain

PID derivative gain

A074

0.00 to 100.0(s)

Derivative gain

PV scale conversion

A075

0.01 to 99.99

Scale for unit conversion of PID feedback

data

 

 

 

 

 

00

OI-L: 4 to 20 mA

PV source setting

A076

01

O-L: 0 to 10 V

02

RS485 communication

 

 

03

Frequency command as pulse train

 

 

10

Operation result (*1)

Output of inverted PID

A077

00

Disabling the inverted output

 

Enabling the inverted output (deviation

deviation

01

 

polarity inverted)

 

 

 

PID variation range

A078

0.0 to 100.0(%)

Range of PID data variation with

reference to the target value

 

 

 

 

 

00

Invalid

PID feed forward selection

A079

01

O-L : 0-10V

02

OI-L : 4-20mA

 

 

 

 

03

O2-L : -10-10V

PID deviation level setting

C044

0.0 to 100.0(%)

Level to determine the OD signal output

Off level of feedback

C052

0.0 to 100.0(%)

Level to determine the FBV signal output

comparison signal

 

 

 

Onlevel of feedback

C053

0.0 to 100.0(%)

Level to determine the FBV signal output

comparison signal

 

 

 

(*1) refer 4.2.12 Frequency operation function

(1) Basic configuration of PID control

 

 

 

 

 

 

 

Feed Forward

invalid

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0-10V

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0-20mA

 

 

 

 

 

 

 

 

 

 

 

 

 

-10-10V

 

 

 

Target value

 

Deviation

 

 

 

 

 

Operation

 

 

 

 

0 to 10 V

 

 

 

 

 

 

 

 

 

 

4 to 20 mA

 

(ε)

 

 

 

 

 

 

quantity

 

 

 

 

 

+

Kp1+

 

1

 

+TdS+

Normal control

M

 

 

 

 

 

 

fs

 

 

 

 

 

 

 

 

 

-

 

 

TiS

 

 

 

by the inverter

 

 

 

 

 

 

 

 

 

 

 

 

 

Feedback

 

 

0 to 10 V

 

 

 

 

Transducer

 

 

 

 

 

 

 

 

4 to 20 mA

 

 

 

 

 

 

 

Sensor

Kp: Proportional gain

Ti: Integral time

Td: Derivative time

s: Operator

ε: Deviation

 

 

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Hitachi SJ700-2 instruction manual PID function