Hitachi SJ700D-004L, Instruction Manual

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Chapter 4 Explanation of Functions
4-91
4.2.98 Torque monitoring function
The torque monitoring function allows you to monitor the
estimated motor output torque when the V/F characteristic curve
selection is the sensorless vector control, 0Hz-range sensorless
vector control, or vector control with sensor.
To monitor the output torque on the digital operator, select code
"d012" on the digital operator.
To monitor the output torque as a signal output from the control circuit terminal block, see Section 4.2.77, "FM
terminal," or 4.2.78, "AM and AMI terminals."
If the constant torque characteristic (VC), reduced-torque characteristic (1.7th power of VP), or free V/f characteristic is
specified for the V/F characteristic curve selection (A044/A244), this function is disabled, and the display on the digital
operator and the signal output from the control circuit terminal block are unpredictable.
The torque monitored by this function is displayed as a ratio to the torque the motor outputs when rotating in
synchronization with the frequency corresponding to the motor's rated output. (The latter torque is 100%.)
Since this function estimates the output torque from the motor current, the accuracy of monitoring is about 20% when
the inverter drives a motor that has the same output ratings as the inverter.
Item Function code Data or range of data Description
V/F characteristic curve
selection
A044/A244
03 Sensorless vector control
04 0Hz-range sensorless vector control
05
Vector control with sensor (not available for
A244)
[FM] siginal selection
[AM] siginal selection
[AMI] siginal selection C027
C028
C029 02 Output torque
11 Output torque (signed) (only for C028)
Motor capacity selection H003/H203
0.20 to 75.0 (kW)
<0.2 to 160(kW)>
Motor pole selection H004/H204 2, 4, 6, 8, or 10 (poles)
(NOTE) <>:applied for 75 to 150kW
4.2.99 Forcing function (FOC)
The forcing function allows you to apply an exciting
current via an input terminal to the inverter to pre-build magnetic
flux when "03" (sensorless vector control), "04" (0Hz-range
sensorless vector control), or "05" (vector control with sensor) is
specified for the V/F characteristic curve selection (A044/A244).
To use this function, assign function "55" (FOC) to an intelligent input terminal.
After the FOC function is assigned, the inverter will accept operation commands only when the FOC terminal is turned
on.
If the FOC terminal is turned off while the inverter is operating the motor, the inverter sets the motor into the
free-running state. If the FOC terminal is turned on subsequently, the inverter restarts the motor according to the
setting of the restart mode after FRS (b088).
A044/A244: V/F characteristic curve selection,
1st/2nd motors
C027: [FM] siginal selection
C028: [AM] siginal selection
C029: [AMI] siginal selection
H003/H203: Motor capacity, 1st/2nd motor
H004/H204: Motor poles setting, 1st/2nd motors
Related code
A044/A244: V/F characteristic curve selection,
1st/2nd motors
C001 to C008: Terminal [1] to [8] functions
Related code
FOC
FW(RV)
Output frequency
Exciting current flows.
The inverter does not operate
the motor because the FOC
terminal is off.
Free running
Restarting according to the
setting of "b088
"