Hitachi SJ7002 Series Instruction Manual page 199

Speed Servo ON
The servo-ON function allows you to set the inverter in a speed-servo-lock state with an
intelligent input during operation. This function is available when A044=05 vector control with
54
Opt. Code sensor for the characteristic V/f curve.
To use the servo-ON function, assign option code 54 to an intelligent input. After making the
[SON]
Symbol
input assignment, the inverter will accept an operation command only when the [SON] terminal
Valid for
is ON.
[1] to [8]
Inputs
If the [SON] terminal is turned OFF during inverter operation, the inverter output enters FRS
Required mode (free-run stop). If the [SON] is turned ON again, the inverter restarts the motor according
A044
Settings to function B088, Restart Mode After FRS.
The inverter does not allow [SON] terminal assignment and [FOC] (forcing function) assign-
Default
Requires
ment at the same time. If both are assigned, the [FOC] has priority (operates normally) and the
config.
terminal
[SON] function is not available.
frequency
Servo-ON [SON]
Current Forcing
The current forcing function applies an excitation current to pre-build magnetic flux in the
motor. The forcing function is available when one of the following vector control modes is
55
Opt. Code configured for use at the inverter output:
• A044 = 03 sensorless vector control
[FOC]
Symbol
• A044 = 04 0Hz-range sensorless vector control
Valid for
[1] to [8]
• A044 = 05 vector control with sensor
Inputs
To use current forcing, assign option code 55 to an intelligent input terminal. After making the
Required
A044, A244
input assignment, the inverter will accept an operation command only when the [FOC] terminal
Settings
is ON.
Default
Requires
If the [FOC] terminal is turned OFF during inverter operation, the inverter output enters FRS
config.
terminal
mode (free-run stop). If the [FOC] is turned ON again, the inverter restarts the motor according
to function B088, Restart Mode After FRS.
frequency
Current forcing [FOC]
Speed-servo lock states
Output
0
FW/RV
Excitation current flows
Output
0
FW/RV
SJ700
Free-run stop Restart after FRS (B088)
Inverter does not follow FW/RV
command because [SON] is OFF
Free-run stop Restart after FRS (B088)
Inverter does not follow FW/RV
command because [FOC] is OFF
4–37
Inverter
2
t
t