Hitachi SJ Series, User Manual

Page: 310 / 786

12-13-3
Chapter 12
Inverter Function
12.13.2 Restraining to avoid overcurrent
• Impact load can cause overcurrent tripping.
• I would like to avoid tripping against momentary
current increase.
• I want to accelerate while suppressing the motor
current.
• I want to prevent tripping caused by sudden
fluctuation of load.
• Setting [bA120] overcurrent suppression selection
to 01 enables the overcurrent suppression function.
• This function suppresses the overcurrent caused
by steep current
increase due to sudden acceleration, etc.
Parameters
• Disable this function when using for elevators, etc.
Suppressing the current causes insufficient torque,
which may result in sliding down of the panier or
anything hanging.
• The overcurrent tripping may take place even if this
function is enabled if the current increases sharply
due to shock load, etc.
• This function will be automatically enabled during
DC braking.
• If the overcurrent suppression function is enabled,
the overcurrent suppression function will be
activated when the motor current exceeds the set
value for [bA121] with momentary current increase.
*1) See "12.14.4 Starting with frequency pull-in" for
details.
Item Parameter Data Description
Overcurrent suppression
selection
[bA120]
00 Disabled
01
Enabled (Overcurrent suppression is
activated.)
Overcurrent suppression
level
[bA121]
Inverter
rated current
×
(0.00~2.00)
Sets the operation level of the
overcurrent suppression function.
Overcurrent suppression
level
when resuming with
frequency pull-in
[bb-46]
Inverter
rated current
×
(0.00~2.00)
Sets the operation level of the
overcurrent suppression function
when activated with frequency
pull-in.*
1)
Q
A
!