Mitsubishi Electric 800 Series Instruction Manual (Function page 136

 Setting the torque bias amount automatically using terminal 4 (Pr.840 =
"3", Pr.846)
• The settings of C38 Terminal 4 bias command (torque/magnetic flux), C39 Terminal 4 bias (torque/magnetic flux),
C40 Terminal 4 gain command (torque/magnetic flux), C41 Terminal 4 gain (torque/magnetic flux) and Pr.846
Torque bias balance compensation can be set automatically according to the load.
• To set the torque bias amount with a voltage input to terminal 4, set Pr.858 Terminal 4 function assignment = "6".
• Set the terminal 4 to accept input of load detection voltage, set "3" in Pr.840 Torque bias selection, and adjust the
parameter settings according to the following procedures.
Setting C38, C39 (Pr.932)
Drive with no load
Setting C40, C41 (Pr.933)
Drive under the
maximum load
Setting Pr.846
Drive with a balanced
load
NOTE
• To perform a torque bias operation after the automatic setting is completed, set Pr.840 to "1" or "2".
 Torque bias operation (Pr.844, Pr.845)
• The torque start-up can be made slower by setting Pr.844 Torque bias filter ≠ "9999". The torque start-up operation at
this time is the time constant of the primary delay filter.
• Set the time for continuing the output torque simply by using the command value for the torque bias in Pr.845 Torque bias
operation time.
Torque bias filter
primary delay time
*1 When pre-excitation is not performed, the torque bias functions at the same time as the start signal.
When the speed
stabilizes, read C38,
C39 (Pr.932)
When the speed
stabilizes, read C40,
C41 (Pr.933)
Read Pr.846
Speed
Torque bias
Pr. 844
constant
Output torque
Time when torque is
Pr. 845
generated by
torque bias setting
∗1
Pre-excitation LX
Start signal
Press .
(C38, C39 (Pr.932)
setting completed)
Press .
(C40, C41 (Pr.933)
setting completed)
Press .
The torque balance
compensation for
power driving is
completed.
The load input at no load
is set as the terminal 4
bias, and a terminal 4 bias
command is automatically
set according to the load.
The load input at the
maximum load is set as
the terminal 4 gain, and a
terminal 4 gain command
is automatically set
according to the load.
The load input at a
balanced load is
automatically set as a
torque bias balance
compensation for power
driving.
10
135
5. Speed Control
5.7 Torque bias
1
2
3
4
5
6
7
8
9