Pid Control - Hitachi SJ300 Series Instruction Manual

3–22
"A" Group: Standard Functions

PID Control

Func.
Name
Code
A071 PID Enable
A072 PID proportional gain
A073 PID integral time
constant
A074 PID derivative time
constant
A075 PV scale conversion
A076 PV source setting
When enabled, the built-in PID loop calculates an ideal inverter output value to cause a loop
feedback process variable (PV) to move closer in value to the setpoint (SP). The current
frequency command serves as the SP. The PID loop algorithm will read the analog input for the
process variable (you specify either current or voltage input) and calculate the output.
• A scale factor in A075 lets you multiply the PV by a factor, converting it into engineering
units for the process.
• Proportional, integral, and derivative gains are all adjustable.
• Optional – You can assign an intelligent input terminal the option code 23, PID Disable.
When active, this input disables PID operation. See
on page 3–49.
• See "PID Loop Operation" on page 4–71
"A" Function
Description
Enables PID function,
two option codes:
00 PID operation OFF
01 PID operation ON
Proportional gain has a
range of 0.2 to 5.0
Integral time constant has a
range of 0.0 to 3600 seconds
Derivative time constant has
a range of 0.0 to 100 seconds
Process Variable (PV) scale
factor (multiplier), range of
0.01 to 99.99
Selects source of Process
Variable (PV), option codes:
00 [OI] terminal (current
input)
01 [O] terminal (voltage
input)
NOTE: The setting A073 for the integrator is the integrator's time constant Ti, not the gain.
The integrator gain Ki = 1/Ti. When you set A073 = 0, the integrator is disabled.
"Intelligent Input Terminal Overview"
for more information.
Defaults
Run
Mode
Edit –FE –FU –FR
Lo Hi
(EU) (US) (JP)
✘ ✔
00 00 00
✔ ✔
1.0 1.0 1.0
✔ ✔
1.0 1.0 1.0
✔ ✔
0.0 0.0 0.0
✘ ✔
1.00 1.00 1.00
✘ ✔
00 00 00
SRW Display
Units
— >A071 PID
SW OFF
— >A072 PID
P 1.0
sec. >A073 PID
I 0001.0s
sec. >A074 PID
D 000.00
— >A075 PID
CONV 001.00
— >A076 PID
INPUT OI