If There Is Mechanical Vibration; The Application Is Making Unusual Sounds; Oscillation And Hunting Occur With V/F Control; Oscillation And Hunting Occur With V/F W/Pg Control - YASKAWA F7 User Manual

http://www.aotewell.com
If the Ground Fault Interrupter Operates When the Drive is Run
The Drive's output is a series of high frequency pulses (PWM), so there is a certain amount of leakage current. This may cause
the ground fault interrupter to operate and cut off the power supply. Change to a ground fault interrupter with a higher leakage
current detection level (i.e., a sensitivity current of 200mA or greater per Unit, with an operating time of 0.1s or more), or one
that incorporates high frequency countermeasures (i.e., one designed for use with a Drive). It will also help to change the
Drive's Carrier Frequency Selection (C6-02) to lower the carrier frequency. In addition, remember that the leakage current
increases as the cable is lengthened.

If There is Mechanical Vibration

Use the following information when there is mechanical vibration.

The application is making unusual sounds.

The following causes are possible:
There may be resonance between the mechanical system's natural frequency and the carrier frequency.
This is characterized by the motor running with no noise generation, but the machinery vibrates with a high-pitched whine. To
prevent this type of resonance, adjust the carrier frequency with parameters C6-02 to C6-05.
There may be resonance between the mechanical system's natural frequency and the output frequency of
the Drive.
To prevent this from occurring, use the jump frequency function in parameters d3-01 to d3-04, or have the driven motor and
load balanced to reduce vibration.

Oscillation and hunting occur with V/F control.

The torque compensation parameter settings may be incorrect for the machine. Adjust parameters C4-01 (Torque
Compensation Gain), C4-02 (Torque Compensation Primary Delay Time Parameter), n1-02 (Hunting Prevention Gain),
C2-01 (S-curve Characteristic Time at Acceleration Start), and C3-02 (Slip Compensation Primary Delay Time) in order.
Lower the gain parameters and raise the primary delay time parameters.

Oscillation and hunting occur with V/F w/PG control.

The Speed Control Loop Gain ASR) parameter setting (C5-01) may be incorrect for the machine. Change the gain to a more
effective level.
If the oscillation cannot be eliminated in this way, set the Hunting Prevention Selection n1-01 = 0 (disabled). Then try
re-adjusting the gain.
Oscillation and hunting occur with Open-Loop Vector control.
The torque compensation parameter settings may be incorrect for the machine. Adjust parameters C4-01 (Torque
Compensation Gain), C4-02 (Torque Compensation Primary Delay Time Parameter), C2-01 (S-curve Characteristic Time at
Acceleration Start), and C3-02 (Slip Compensation Primary Delay Time) in order. Lower the gain parameters and raise the
primary delay time parameters.
Vector Control may not perform optimally if Auto-Tuning has not been performed. Therefore, perform Auto-Tuning.
Alternatively, change the Control Method Selection (A1-02) to V/F Control (0 or 1).
Tel: +(86) 755 8660 6182
Aotewell
Diagnostics & Troubleshooting 6 - 25
Aotewell
Email: Sales@aotewell.com
http://www.aotewell.com