Adjust The Output Torque Of The Motor (Current); Manual Torque Boost (Pr. 0, Pr. 46, Pr. 112) - Mitsubishi Electric FR-A720-0.4K Instruction Manual

Adjust the output torque of the motor (current)

4.8 Adjust the output torque of the motor (current)

Purpose
Set starting torque manually
Automatically control output current
according to load
Compensate for motor slip to secure
low-speed torque
Limit output current to prevent inverter
trip
4.8.1

Manual torque boost (Pr. 0, Pr. 46, Pr. 112)

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.
Three types of starting torque boost can be changed by switching terminals.
Parameter
Name
Number
0 Torque boost
Second torque
46
boost
Third torque
112
boost
(1) Starting torque adjustment
⋅ On the assumption that Pr. 19 Base frequency voltage is 100%, set the output voltage at 0Hz in % in Pr. 0 (Pr. 46, Pr. 112).
⋅ 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.
142
Parameter that must be Set
Manual torque boost
Advanced magnetic flux
vector control
Slip compensation
Stall prevention operation
Initial Value
0.4, 0.75K
1.5K to 3.7K
5.5K, 7.5K
11K to 55K
75K or more
9999
9999
100%
Output
voltage
Pr.0
Setting
Pr.46
range
Pr.112
Output
0
frequency
(Hz)
Pr. 0, Pr. 46, Pr. 112
Pr. 71, Pr. 80, Pr. 81, Pr. 89, Pr. 450,
Pr. 451, Pr. 453, Pr. 454,
Pr. 569, Pr. 800
Pr. 245 to Pr. 247
Pr. 22, Pr. 23, Pr. 66,
Pr. 154, Pr. 156, Pr. 157
V/F V/F V/F
Setting
Range
6%
4%
3% 0 to 30% Set the output voltage at 0Hz as %.
2%
1%
Set the torque boost value when the
0 to 30%
RT signal is on.
9999 Without second torque boost
Set the torque boost value when the
0 to 30%
X9 signal is on.
9999 Without third torque boost
Base
frequency
Refer to Page
142
144
147
148
Description