Adjust The Output Torque Of The Motor (Current); Manual Torque Boost (Pr.0, Pr.46); Simple Magnetic Flux Vector Control (Pr.80, Pr.90) - Mitsubishi Electric F700 Instruction Manual

3.2 Adjust the output torque of the motor (current)

Purpose
Set starting torque manually
Automatically control output power
according to load
Compensate for motor slip to secure
low-speed torque
Limit output power to prevent inverter
trip
Select overload according to application Load pattern selection
Change the overload current rating
specifications
3.2.1

Manual torque boost (Pr.0, Pr.46)

You can compensate for a voltage drop in the low-frequency region to improve motor torque reduction in the
low-speed range.
Motor torque in the low-frequency range can be adjusted to the load to increase the starting motor torque.
The starting torque boost can be changed by switching between terminals.
Parameter
Name
Number
0 Torque boost
Second torque boost
46
*1
*1 They can be set when Pr. 160 User group read selection = "0". (Refer to page 140.)
100%
Output
voltage
Pr.0
Setting
Pr.46
range
0 Output frequency(Hz)
(2) Set multiple base frequencies (RT signal, Pr. 46)
⋅ Use the second torque boost when changing the torque boost according to application or when using multiple
motors by switching between them by one inverter.
⋅ Pr. 46 Second torque boost is made valid when the RT signal turns on.
REMARKS
⋅ The RT signal acts as the second function selection signal and makes the other second functions valid. (Refer to page 87)
⋅ The RT signal is assigned to the RT terminal in the default setting. By setting "3" to any of Pr. 178 to Pr. 189 (Input terminal
function selection), you can assign the RT signal to the other terminal.
CAUTION
⋅ Increase the setting when the distance between the inverter and motor is long or when motor torque is insufficient in the low-
speed range. If the setting is too large, an overcurrent trip may occur.
⋅ When simple magnetic flux vector control is selected in Pr. 80, the settings of Pr. 0 and Pr. 46 are invalid.
⋅ When using the inverter dedicated motor (constant torque motor) with the 00126 or 00170, set the torque boost value to 2%.If
the initial set Pr. 71 value is changed to the setting for use with a constant-torque motor, the Pr. 0 setting changes to the
corresponding value in above.
⋅ Changing the terminal assignment using Pr. 178 to Pr. 189 (Input terminal function selection) may affect the other functions.
Please make setting after confirming the function of each terminal.
♦ Parameters referred to ♦
Pr. 3 Base frequency, Pr. 19 Base frequency voltage
Pr. 71 Applied motor Refer to page 80
Pr. 80 Motor capacity (simple magnetic flux vector control)
Pr. 178 to Pr.189 (Input terminal function selection)

Adjust the output torque of the motor (current)

Parameter that must be set
Manual torque boost
Simple magnetic flux
vector control
Slip compensation
Stall prevention
operation
Multiple rating setting
Initial Value
00023 6%
00038 to 00083 4%
00126, 00170 3%
00250 to 00770 2%
00930, 01160 1.5%
01800 or more 1%
9999
(1) Starting torque adjustment
⋅ On the assumption that Pr. 19 Base frequency voltage is 100%, set
the output voltage at 0Hz in % to Pr. 0 (Pr. 46).
⋅ Adjust the parameter little by little (about 0.5%), and check the
motor status each time. If the setting is too large, the motor will
overheat. The guideline is about 10% at the greatest.
Base
frequency
Refer to page 64
Refer to page 54
Refer to page 85
Pr.0, Pr.46
Pr.80, Pr.90
Pr.245 to Pr.247
Pr.22, Pr.23, Pr.66,
Pr.154, Pr.156, Pr.157
Pr.14
Pr.570
Setting
Description
Range
0 to 30% Set the output voltage at 0Hz as %.
Set the torque boost value when
0 to 30%
the RT signal is on.
9999 Without second torque boost
Refer to page
53
54
55
56
60
61
Pr. 1
page 62
Pr.45
page 74
Pr.47
page 64
3
53