If There Is Low Speed Control Accuracy At High-Speed Rotation In Open-Loop Vector Control Method; If The Motor Overheats; If There Is Mechanical Oscillation - YASKAWA FSDrive-MV1S Instructions Manual

If There is Low Speed Control Accuracy at High-speed Rotation in Open-
loop Vector Control Method
The motor's rated voltage is high.
The Inverter's maximum output voltage is determined by its input voltage. (For example, if 3300 VAC is input,
then the maximum output voltage will be 3300 VAC.) If, as a result of vector control, the output voltage refer-
ence value exceeds the Inverter output voltage maximum value, the speed control accuracy will decrease. Use
a motor with a low rated voltage (i.e., a special motor for use with vector control), or change to flux vector
control.

If the Motor Overheats

Take the following steps if the motor overheats.
The load is too big.
If the motor load is too heavy and the motor is used with the effective torque exceeding the motor's rated
torque, the motor will overheat. Some motor rating are given for short period performance and are not contin-
uous ratings. Reduce the load amount by either lightening the load or lengthening the acceleration/decelera-
tion time. Also consider increasing the motor capacity.
The ambient temperature is too high.
The motor rating is determined within a particular ambient operating temperature range. The motor will burn
out if it is run continuously at the rated torque in an environment in which the maximum ambient operating
temperature is exceeded. Lower the motor's ambient temperature to within the acceptable ambient operating
temperature range.
Autotuning has not been performed for vector control
Vector control will not perform if autotuning has not been performed. Perform autotuning, or set the motor
constants through calculations.

If There is Mechanical Oscillation

Use the following information when there is mechanical oscillation.
The machinery is making unusual sounds.
The following cause is possible.
There may be resonance between a machine's characteristic frequency and the output fre-
quency of the Inverter.
To prevent this from occurring, either use the jump frequency functions in constants d3-01 to d3-04 or install
rubber padding on the motor base to reduce oscillation.
Troubleshooting
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