YASKAWA CIMR-VU BA0001 Technical Manual page 306

6.9 Troubleshooting without Fault Display
n Oscillation or Hunting
Cause
Insufficient tuning in Open Loop Vector Control
Auto-Tuning has not yet been performed (required for
Open Loop Vector Control).
Insufficient tuning in V/f Control.
Gain is too low when using PID control.
The frequency reference is assigned to an external
source and the signal is noisy.
The cable between the drive and motor is too long.
n PID Output Fault
Cause
No PID feedback input.
The level of detection and the target value do not
correspond with each other.
Reverse drive output frequency and speed detection.
When output frequency rises, the sensor detects a
speed decrease.
n Insufficient Motor Torque
Cause
Auto-Tuning has not yet been performed (required for
OLV Control).
The control mode was changed after performing Auto-
Tuning.
Only Line-to-Line Resistance Auto-Tuning was
performed.
n Motor Rotates After the Drive Output is Shut Off
Cause
Low DC Injection Braking and the drive cannot
decelerate properly.
306
Adjust the following parameters in the order listed.
An increase in gain should be followed with an increase in the primary delay time constant.
• C4-02 (Torque Compensation Primary Delay Time)
• n2-01 (Speed Feedback Detection Control [AFR] Time Constant 1)
• C3-02 (Slip Compensation Primary Delay Time)
The response for torque compensation and slip compensation will drop as the time constant is
increased.
Perform Auto-Tuning.
Set motor parameters after calculating the proper values.
Change the motor control method to V/f Control (A1-02 = "0").
Reduce the gain.
• n1-02 (Hunting Prevention Gain Setting)
• n1-03 (Hunting Prevention Time Constant Setting)
Check the period of oscillation and adjust P, I, and D settings accordingly.
• Ensure that noise is not affecting the signal lines.
• Separate main circuit wiring and control circuit wiring.
• Use twisted-pair cables or shielded wiring for the control circuit.
• Increase the analog input time filter constant (H3-13).
• Perform Auto-Tuning.
• Reduce the length of the cable.
• Check the multi-function analog input terminal settings.
• Set multi-function analog input terminal A1 or A2 for PID feedback (H3-02 or H3-10 = "B").
• A signal input to the terminal selection for PID feedback is necessary.
• Check the connection of the feedback signal.
• Check the various PID-related parameter settings.
• No PID feedback input to the terminal causes the value detected to be 0, causing a PID fault
and the drive to operate at max frequency.
• PID control keeps the difference between target and detection values at 0. Set the input level
for the values relative to one another.
• Use analog input gains H3-03/11 to adjust PID target and feedback signal scaling.
Set PID output for reverse characteristics (b5-09 = "1").
Perform Auto-Tuning.
Perform Auto-Tuning again.
Perform Rotational Auto-Tuning.
• Adjust the DC Injection braking settings.
• Increase the value of b2-02 (DC Injection Braking Current).
• Increase the b2-04 (DC Injection Braking Time at Stop).
YASKAWA ELECTRIC SIEP C710606 18F YASKAWA AC Drive – V1000 Technical Manual
Possible Solutions
Possible Solutions
Possible Solutions
Possible Solutions