Hitachi WJ Series

Chapter 9 Inverter Functions
9-9-14
9.9.7 Restarting after Overvoltage/Overcurrent
 Overvoltage or overcurrent rarely occurs, so how to restart the system when there is no problem
in the system?
 How to continue to run the system when overvoltage or overcurrent occurs?
 When overvoltage or overcurrent occurs, the inverter can be set to trip or restart without
tripping using "Restart mode selection after overvoltage/overcurrent error [b008]".
 When restart is selected, the restart operation is repeated the number of times specified in
"Number of retries after overvoltage/overcurrent [b010]", and then the inverter trips after the
specified reties are finished.
 When frequency correspondence restart is performed ([b008] = 02, 03), the restart mode is
active frequency matching restart at the frequency of the previous output interruption. For
details, refer to "9.7.3 Starting with Frequency Matching".
 To perform an active frequency matching restart ([b008] = 04), refer to "9.7.4 Starting with
Active Frequency Matching" for details.
 When overcurrent continues to occur, this may be caused by acceleration time specified too
short, excessive loads, or the motor being locked.
 When overvoltage continues to occur, this may be caused by deceleration time specified too
short, excessive loads, or the motor rotated by an external force.
 Even when the restart operation is selected, if the trip factor has not been solved after the "Retry
wait time after overvoltage/overcurrent error [b011]", the inverter will detect the trip again. In
this case, increase the retry wait time.
Code
Item
Description
Data
[b008]
Restart mode selection
after overvoltage/
overcurrent error
Trip occurs.
00
The inverter restarts from 0 Hz.
01
Performs the frequency matching restart
(= Active frequency matching restart at the
frequency of the previous output interruption).
02
After frequency matching restart (= Active
frequency matching restart at the frequency of
the previous output interruption), deceleration
stop and trip occur.
03
Performs the active frequency matching restart.
04
[b010]
Number of retries after
overvoltage/overcurrent
Sets the number of retries for when there is an
overvoltage/overcurrent.
1 to 3 (times)
[b011]
Retry wait time after
overvoltage/overcurrent
error
Sets the wait time from when overvoltage or
overcurrent is detected until the restart.
0.3 to 100.0 (s)
Q
A
!