Hitachi WJ C1 Series User Manual

Chapter 9 Inverter Functions
9-7-4
9.7.4 Starting with Active Frequency Matching
 How to start the inverter so that it quickly follows the command frequency regardless of the
rotation speed frequency when the motor is idling?
 How to have the inverter follow the frequency command quickly during trip retry, free run stop,
reset, and supplying power, etc.?
 The active frequency matching restart function allows the motor to quickly pull from idle motor
rotation speed to a set frequency and restart while suppressing current increase. For more
details on this operation, refer to "(Example 1) Active frequency matching restart ".
 The active frequency matching function can be set for each of the following functions.
- Instantaneous power failure/undervoltage restart ([b001] = 04)
- Overcurrent/overvoltage restart ([b008] = 04)
- Restart after free-run release ([b088] = 02)
- Restart after reset release or powering-on ([C103] = 02)
 When restarting after free-run release or reset release, the inverter restarts once the free-run or
reset is released, and the standby duration set in the "Retry wait time after instantaneous power
failure/undervoltage error [b003]" since the RUN command turns on has elapsed.
 The active frequency matching restart function is only available with induction motor drives.
 When the RUN command input source is set to the RUN key on the keypad, the RUN command
is turned off when "Free run stop [FRS]" or "Reset [RS]" is turned on. If restart after free-run
release or restart after reset release is set, pressing the RUN key on the keypad to start operation
will start the retry operation. In case of an instantaneous power failure, undervoltage,
overvoltage, or overcurrent retry operation, the RUN status from the keypad is maintained.
Code
Item
Description
Data
[b028]
Active frequency
matching restart
level
Sets the current limit value at the active
frequency matching restart.
(0.2 to 2.0) × rated current (A)
(ND mode)
(0.2 to 1.5) × rated current (A)
(LD mode)
[b029]
Active frequency
matching restart
constant (speed)
Sets the deceleration time when the current is
increased.
0.1 to 3000.0 (s)
[b030]
Active frequency
matching restart
speed selection
Starts at the frequency of the previous output
interruption.
00
Starts at the maximum frequency setting.
01
Starts at the current command frequency.
02
Retry wait time after instantaneous power
failure/undervoltage error [b003]
(1) Output will start at the frequency set
by [b030] after the retry wait time
elapses.
(2) Meanwhile, output power is gradually
increased to prevent the occurrence
of overcurrent and other issues.
(Dashed line in the figure on the left)
(3) If the output current exceeds [b028],
deceleration occurs in the output
frequency as per [b029] to suppress
the output current.
(4) Normal operation is possible when
the output frequency and output
voltage counterbalance each other.
Free running
Interrupting
factor
Output frequency
(Output voltage
(dashed line))
Motor speed
Active frequency
matching restart
Output
current
Active frequency matching restart level [b028]
(1)
(3)
(2)
(4)
◼ (Example 1) Active frequency matching restart
[b030]
A
Q
!

Hitachi WJ C1 Series Specifications

General

Brand	Hitachi
Model	WJ C1 Series
Category	Inverter
Language	English