Robotics in Manufacturing
SRVO-025

SRVO-025: Motn dt overflow

The motion command computed for the axis was too large for the servo system to accept - an internal command overflow rather than a mechanical fault.

What it means

The motion command computed for the axis was too large for the servo system to accept - an internal command overflow rather than a mechanical fault. Rare, and FANUC treats it seriously: the remedy path leads to their service organization.

Common causes

Ranked by what technicians most often find, most likely first.

  1. Internal motion command fault - software-side, not typically caused by anything a tech did at the pendant.

How to fix it

  1. Cold start: power off, hold SHIFT+RESET on the pendant, power on while still holding.
  2. If it recurs, run the Diagnostic Log function (FNCT > Diagnostic log) BEFORE doing anything else, take an image backup, and contact FANUC service with both. The diagnostic data captured immediately after the event is what makes the case solvable.

Quick facts

Category
Servo
Affected series
R-30iB; R-30iB Mate; R-30iB Plus; R-30iB Mate Plus
Alarm family
SRVO

Related codes

Verified against FANUC documentation (B-83284EN-1).Last reviewed: 2026-07-09.Editorial process