Hitachi WJ Series

Chapter 9 Inverter Functions
9-2-16
9.2.11 Setting Frequency Command by Calculation Operation
 How to multiply the frequency command by a particular gain value?
 How to set the frequency command according to the sum of two input values?
 How to switch between forward and reverse rotation by subtracting the frequency command?
 To use the result of the frequency calculation function as the output frequency command, set
the "Frequency input source selection [A001]
*1
" to "Calculation function result (10)".
 The frequency calculation function can also be used for the PID feedback input. In such a case,
set the "PID feedback input source selection [A076]" to "Calculation function result (10)".
Code
Item
Description
Data
[A001]
*1
Frequency input
source selection
The calculation operation set in [A143] is performed on the input
values from the command input sources set in [A141] and [A142].
The result of this calculation is then used as the output frequency
command.
10
[A076]
PID feedback input
source selection
The calculation operation set in [A143] is performed on the input
values from the command input sources set in [A141] and [A142].
The result of this calculation is then used as the PID feedback value.
10
[A141]/
[A142]
Frequency input
selection 1/2 for
calculation function
Parameter setting ([A020]
*1
)
00
Remote operator potentiometer [POT]
01
[Ai1] voltage input
02
[Ai2] current input
03
Modbus communication
04
Communication option board
05
Pulse input
07
[A143]
Calculation function
operator selection
Addition: [A141] + [A142]
00
Subtraction: | [A141] - [A142] | (Absolute value)
01
Multiplication: [A141] × [A142]
02
*1. "2nd-motor control [SET]" target parameter. The second control parameter is also subject to setting.
 "Remote control Speed-UP funtion [FUP]/Remote control Speed-DOWN function [FDN]" are
disabled for the frequency calculation function. The frequency cannot be changed by the keys
on the keypad while the "Output frequency monitor [d001]", "Output frequency scale conversion
monitor [d007]", or "Output frequency setting or monitor [F001]" is displayed.
 The same setting can be applied to [A141] and [A142]. The multiplication operation can also be
used to calculate the square of a command input source.
■ Example of the frequency calculation function
(Example 1) Applying gain
[A141] = [Ai1] voltage input
[A142] = Parameter ([A020] = 3 Hz)
[A143] = Multiplication (02)
Frequency command
Operation
result
frequency
command
3 Hz
20 Hz
60 Hz
[A142] =
[A020] setting
[A141] =
[Ai1] input
(Example 2) Addition
[A141] = [Ai1] voltage input
[A142] = [Ai2] current input
[A143] = Addition (00)
(Example 3) High-speed forward rotation and
Low-speed reverse rotation
[A141] = [Ai1] voltage input
[A142] = Parameter ([A020] = 10 Hz)
[A143] = Subtraction (01)
Frequency command
Operation
result
Frequency
command
10 Hz
40 Hz
50 Hz
[A142] =
[Ai2] input
[A141] =
[Ai1] input
40 Hz
Frequency command
Operation
result
Frequency
command
10 Hz
40 Hz
[A142] =
[A020] setting
[A141] =
[Ai1] input
10 Hz
30 Hz
10 Hz
Forward
rotation
Reverse
rotation
Q
A
!