Hitachi SJ Series, User Manual

Page: 340 / 786

12-14-13
Chapter 12 Inverter Function
12.14.8 Making torque rise faster
• How to make torque rise faster
• The motor starts rotating slowly after an operation
command is given.
• This function is to preliminarily establish magnetic
flux by applying an excitation current via the forcing
terminal [FOC] command.
• This function operates if the input terminal function
066 [FOC] is assigned.
• When [AA115] Stop mode selection is set to 00
■
Parameter
* 1) See "12.14.3 Starting by picking up frequency".
• If torque at starting is insufficient, it may improve by
adjusting the boost amount at starting [HC111],
[HC112] or the speed response [HA115].
See "12.9 Selecting the Motor Control Mode
according to Motor and Load".
• This function is effective when the IM sensorless
vector control, IM zero-speed range sensorless
vector control, or IM vector control with sensor is
selected for the control mode [AA121].
• If [FOC] is assigned to the input terminal function,
operation will not be accepted unless [FOC] is
turned on.
• If [FOC] is turned off during operation, the inverter
will be operated according to [AA115] Stop mode
selection. If a free run occurs, restart will take place
according to the setting for the restart after free-run
stop.
• When [AA115] Stop mode selection is set to 01
*2) See "12.14.4 Starting with frequency pull-in".
• If torque at starting is insufficient, it may improve by
using the torque bias function. See "12.11.6
Operating with torque command added".
Item Parameter Data Description
Input terminal function [CA-01]~[CA-11] 066 Forcing function [FOC]
Stop mode selection [AA115]
00
Performs the deceleration stop when the
operation command is off.
01
Performs the free-run when the operation
command is off.
Restart after free-run stop [bb-40]
00 Performs the 0 Hz restart.
01 Performs frequency matching restart.* 1)
02 Performs frequency pull-in restart.* 2)
Retry wait time after
instantaneous power
failure/under-voltage
[bb-26] 0.3~100.0(s)
Sets the wait time after the operation
command.
Q
A
!
!
FOC
FW
Output
frequency
The inverter does not run
because FOC terminal =
OFF.
Excitation
current flows.
Deceleration stop
Excitation current does not flow.
FOC
FW
Output
frequency
The inverter does not
run because FOC
terminal = OFF.
Restart after free-run stop
Free-running
Excitation
current flows.
Excitation current does not
flow.