Hitachi L700 Series, Instruction Manual, Page: 89 / 263

Chapter 4 Explanation of Functions
4 - 27
(2) PID operation
1) P operation
The proportional (P) operation stands for the operation in which the change in operation quantity is in
proportion to the change in target value.
2) I operation
The integral (I) operation stands for the operation in which the operation quantity increases linearly over
time.
3) D operation
The derivative (D) operation stands for the operation in which the operation quantity changes in
proportion to the rate of change in the target value.
The PI operation is a combination of the P operation 1) and I operation 2). The PD operation is a
combination of the P operation 1) and D operation 3). The PDI operation is a combination of the P
operation 1), I operation 2), and D operation 3).
(3) PV source setting
Select the terminal to be used for the feedback signal with the PV source setting function (A076).
The terminal to input the target value follows the frequency source setting (A001). The terminal selected by
the PV source setting (A076) is excluded.
If the control circuit terminal block ("01") has been specified for frequency source setting "A001", the
setting of AT selection (A005) is invalid.
The table below shows how the PID target value is selected according to the setting of "A006" when the
analog input is selected by the PV source setting and the control circuit terminal block ("01") is specified for
"A001".
PV source setting (A076)
PID target value
A006=00 A006=01 A006=02 A006=03
00 (OI-L)
O + O2
(non-reversible)
O + O2
(reversible)
O
01 (O-L)
OI + O2
(non-reversible)
OI + O2
(reversible)
OI
10 (operation
result)
Operation targets include the
input to the OI terminal. O + O2
(non-reversible)
O + O2
(reversible)
O
Operation targets include the
input to the O terminal. OI + o2
(non-reversible)
OI + O2
(reversible)
OI
Operation targets are the inputs
to the OI and O terminals. O2
(reversible)
A072
A072
Change in steps
Target value
Operation quantity
Linear change
Large
Small
Large
Small
A073 A073
Target value
Operation quantity
Small
Large
Small
Large
A074
A074
Target value
Operation quantity
Large
Small
Large
Small