[Cause]
An internal exception occurred.
[Countermeasure]
Please obtain a mirror backup through the abnormal status recording function ("Abnormal status recording" in the auxiliary menu) and contact the service center before performing other operations (power off and inching operation) after this alarm occurs. If the status recording function cannot be used during an abnormality, please record the situation and operation steps before the alarm is issued, obtain an image backup, and contact the service center.