[Cause]
PowerWaveErrorCode No.91 occurred. The sensing lead polarity could not be updated correctly.
[Countermeasure]
Check the control board status. If there is no improvement, Before performing other operations (power-off and jogging operations) after this alarm occurs, use the abnormal-condition recording function (“Abnormal Condition Record” in the auxiliary menu) to obtain an image backup and contact the service center. If the abnormal-condition recording function cannot be used, record the conditions and operating steps leading up to the alarm, obtain an image backup, and contact the service center.