6.8 Troubleshooting without Fault Display n Connected Machinery Vibrates When Motor Rotates Excessive Motor Oscillation and Erratic Rotation Unexpected Noise from Connected Machinery Note: The drive may have trouble assessing the status of the load due to white noise generated when using Swing PWM (C6-02 = 7).
n Oscillation or Hunting n Motor Rotates After the Drive Output is Shut Off n ov or Speed Loss Occurs When Starting into a Rotating Load n Output Frequency is not as High as Frequency Reference n Buzzing Sound from Motor at 2 kHz Troubleshooting 6 n Motor Does Not Operate When the RUN Button on the Digital Operator is Pressed SIEP C710606 33A OYMC AC Drive – J1000 User Manual 137 Cause Possible Solutions Poor balance between motor phases. Check drive input power voltage to ensure that it provides stable power. Cause Possible Solutions The carrier frequency is at the resonant frequency of the connected machinery. Adjust the carrier frequency using parameters C6-02 through C6-05.
The drive output frequency is the same as the resonant frequency of the connected machinery. • 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. Cause Possible Solutions Insufficient tuning. Adjust Hunting prevention Gain Setting (n1-02). The frequency reference is assigned to an external source and the signal is noisy. • 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).
The cable between the drive and motor is too long. • Reduce the length of the cable. Cause Possible Solutions Low DC Injection Braking and the drive cannot decelerate properly. • 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). Cause Possible Solutions The load is already rotating when the drive is trying to start it. • Stop the motor using DC Injection braking. Restart the motor. • Increase the value of b2-03 (DC Injection Braking Time at start). • Set a multi-function input terminal for external Speed Search command (H1-=“61” or “62” during restart).
Cause Possible Solutions Frequency reference is set within the range of the Jump Frequency. • Adjust the parameters used for the Jump Frequency function (d3-01, d3-02). • Enabling the Jump Frequency prevents the drive from outputting the frequencies specified in the Jump Frequency range. Upper limit for the frequency reference has been exceeded. • Set the maximum output frequency and the upper limit for the frequency reference to more appropriate values (E1-04, d2-01). • The following calculation yields the upper value for the output frequency = E1-04 x d2-01 / 100 Large load triggered Stall Prevention function during acceleration. • Reduce the load.
• Adjust the Stall Prevention level during acceleration (L3-02). Cause Possible Solutions Exceeded 110% of the rated output current of the drive while operating at low speeds. • If the output current rises too high at low speeds, the carrier frequency automatically reduces and causes a whining or buzzing sound. • If the sound is coming from the motor, disable carrier frequency derating (L8-38 = “0”). • Disabling the automatic carrier frequency derating increases the chances of an overload fault (oL2). Switch to a larger capacity motor if oL2 faults occur too frequently. Cause Possible Solutions The LOCAL/REMOTE mode is not selected properly. Press the LOCAL/REMOTE button to switch.
The LO/RE LED should be on for LOCAL mode. The drive is not in drive mode. A run command will not be issued. Exit to the drive mode and cycle the run command. The frequency reference is too low. • If the frequency reference is set below the frequency set in E1-09 (Minimum Output Frequency), the drive will not operate. • Raise the frequency reference to at least the minimum output frequency.