YASKAWA Z1000U Technical Manual page 241

Cause
PID control is enabled, and the drive is consequently
adjusting the output frequency to match the PID
setpoint. The drive will only accelerate to the
maximum output frequency set in E1-04 while PID
control is active.
u
Excessive Motor Oscillation and Erratic Rotation
Cause
Poor balance between motor phases.
Hunting prevention function is disabled.
u
Deceleration Takes Longer than Expected
Cause
L3-04 is set incorrectly.
The deceleration time is set too long.
Insufficient motor torque.
Load exceeded the internal torque limit determined by
the drive rated current.
u
Noise From Drive or Motor Cables When the Drive is Powered On
Cause
Relay switching in the drive generates excessive noise.
u
Ground Fault Circuit Interrupter (GFCI) Trips During Run
Cause
Excessive leakage current trips GFCI.
u
Connected Machinery Vibrates When Motor Rotates
n Unexpected Noise from Connected Machinery
Cause
The carrier frequency is at the resonant frequency of
the connected machinery.
The drive output frequency is the same as the resonant
frequency of the connected machinery.
YASKAWA SIEP YAIZ1D 01C Z1000U HVAC MATRIX Drive Bypass Technical Manual
If PID control is not necessary for the application, disable it by setting b5-01 to 0.
Check drive input power voltage to ensure that it provides stable power.
Set n1-01 to 1 to enable Hunting Prevention.
Check the Stall Prevention level during deceleration (L3-04).
Set deceleration time C1-02 to a more appropriate value.
• Assuming parameter settings are normal and that no overvoltage occurs when there is
insufficient torque, it is likely that the demand on the motor has exceeded the motor capacity.
• Use a larger motor.
Switch to a larger capacity drive.
• Lower the carrier frequency (C6-02).
• Install a noise filter on the input side of drive input power.
• Install a noise filter on the output side of the drive.
• Place the wiring inside a metal conduit to shield it from switching noise.
• Ground the drive and motor properly.
• Separate the main circuit wiring and the control lines.
• Make sure wires and the motor have been properly grounded.
• Check the wiring and rating of peripheral devices.
• Increase the GFCI sensitivity or use GFCI with a higher threshold.
• Lower the carrier frequency (C6-02).
• Reduce the length of the cable used between the drive and the motor.
• Disable the internal EMC filter.
Adjust the carrier frequency using parameter C6-02.
• Adjust the parameters used for the Jump frequency function (d3-01 through d3-04) to skip the
problem-causing bandwidth.
• Place the motor on a rubber pad to reduce vibration.
6.9 Troubleshooting without Fault Display
Possible Solutions
Possible Solutions
Possible Solutions
Possible Solutions
Possible Solutions
Possible Solutions
6
241