SRVO-121: Excessive acc/dec time
Internal servo alarm: the computed acceleration time came out too long - a motion-planning fault FANUC wants diagnostic data for, not something fixed at the pendant.
What it means
Internal servo alarm: the computed acceleration time came out too long - a motion-planning fault FANUC wants diagnostic data for, not something fixed at the pendant.
Common causes
Ranked by what technicians most often find, most likely first.
- Internal motion software condition; not a configuration or mechanical issue a tech can isolate on site.
How to fix it
- Run Diagnostic Log (FNCT > Diagnostic log) before any other operation, take an image backup, and contact FANUC with both. If the log can't run, document the exact events leading up to the alarm.
Quick facts
- Category
- Servo
- Affected series
- R-30iB; R-30iB Mate; R-30iB Plus; R-30iB Mate Plus
- Alarm family
- SRVO