Operating Instructions

Descriptions of Parameter Settings
Adjustment and Application
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● With a large motor load, a part of the drive output voltage is absorbed by the stator winding resistor; therefore,
the air gap magnetic field is insufficient. This causes insufficient voltage at motor induction and results in
excessive output current but insufficient output torque. Auto-torque compensation can automatically adjust the
output voltage according to the load and keep the air gap magnetic fields stable to get the optimal operation.
● In the V/F control, the voltage decreases in direct proportion with decreasing frequency. The torque decreases
at low speed because of a decreasing AC resistor and an unchanged DC resistor. The auto-torque
compensation function increases the output voltage at low frequency to get a higher starting torque.
● When the compensation gain is set too high, it may cause motor over-flux and result in a too large output
current of the drive, motor overheating or trigger the drive’s protection function.