What the 3910 alarm means

A programmed Cartesian move demanded a joint speed above the axis limit; the controller rejects or halts the motion. We see this alarm constantly when servicing EFORT EC2-S controller + TSINO drives systems, and the first on-site pass usually pins down the cause.

Most common causes

  • Linear move passing near a singularity
  • Programmed TCP speed too high for the posture
  • Wrong speed override inherited from an earlier program section
Field note: Based on our handling experience the first cause is the most frequent — use it as your starting point.

Step-by-step field fix

  1. Re-teach the path to avoid the singular posture
  2. Reduce TCP speed on the failing segment
  3. Check speed override values in the program
  4. Use joint moves for large posture changes
  5. Verify by dry-running at low override
Safety first: For EFORT 3910, this alarm family points at arm motion control: after a reset the arm can move unexpectedly, and anyone inside the working envelope is at strike and pinch risk. On site you may look at after confirming power-off the first step yourself: Re-teach the path to avoid the singular posture. Beyond that it is the arm working envelope work - leave it to a professional.

How we diagnose motion alarms on site

EFORT 3910 belongs to the motion & path family. On EFORT 3910 the failing stage is matched servo drives assigned per axis in the cabinet on the EFORT robot controller - the gap between command and execution: trajectory planning, joint limits, singularities, following error and mechanical resistance. We start reading EFORT 3910 at the pendant alarm list (four-digit codes, 1xxx / 3xxx / 4xxx segments).

The chain involved in EFORT 3910 runs: program command -> trajectory planner -> joint targets -> servo execution -> actual position feedback -> deviation compare.

If Linear move passing near a singularity on EFORT 3910 comes with a feeling of drag, the direction is clear: Following error that stays high on one axis only is usually rising mechanical resistance, not a weak servo. We turn the axis by hand with the brake released to feel smoothness, and listen to the reducer for once-per-revolution knocking - a single tick per turn on an RV reducer usually means internal bearing or cycloid damage. Grease that is black, dry or carries metal powder is the plainest evidence. Left alone, this graduates from a motion alarm to a scrapped reducer.

Field notes on this page cover EFORT 3910 (Joint Speed Limit Exceeded (EC2-S)); written by the Henghuan repair team, updated 2026-10-01.

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Related Motion & Path alarms

3901 — Position Deviation Over Limit (EC2-S)
Same family: this code belongs to the Motion & path alarms family - the page collects all Motion & path-family codes we have handled, with the common inspection order and spares.
Other brands: we also keep field-fix libraries for JAKA · AUBO · ROKAE and more — see the complete alarm code hub.

Frequently asked questions

QWhat does the EFORT 3910 alarm mean?

A programmed Cartesian move demanded a joint speed above the axis limit; the controller rejects or halts the motion. We see this alarm constantly when servicing EFORT EC2-S controller + TSINO drives systems, and the first on-site pass usually pins down the cause. EFORT 3910 sits in the motion & path family; on our work orders the highest-frequency trigger for this code is "Linear move passing near a singularity".

QCan I clear a EFORT 3910 alarm myself?

Whether EFORT 3910 clears on its own depends on the outcome of "Re-teach the path to avoid the singular posture". Finish the flow with "Verify by dry-running at low override" to confirm EFORT 3910 - do not skip it. If that step is clean, the second most frequent cause on EFORT 3910 is "Programmed TCP speed too high for the posture". Two attempts and still there means stop: EFORT 3910 involves the arm working envelope, and running EFORT 3910 on can turn a repairable fault into a replacement.

QFor motion alarms like EFORT 3910, can you triage remotely first?

The commonest causes we see on EFORT 3910 are "Linear move passing near a singularity, Programmed TCP speed too high for the posture, Wrong speed override inherited from an earlier program section", so we stock the van against those. For EFORT 3910 specifically, we carry mechanical and configuration items: grease, limit switches, drag-chain segments, encoder cables and the parameter sheets for common reducers. For EFORT 3910, motion alarms can often be narrowed remotely first, so an on-site visit is not always immediate. Before we roll, tell us what EFORT 3910 shows on the pendant alarm list (four-digit codes, 1xxx / 3xxx / 4xxx segments) and what the machine was doing - phone or video triage is free.

This page on EFORT 3910 was written by the Henghuan Robotics repair team from field service experience. Alarm descriptions are our own summary for troubleshooting reference and may vary by controller and software version — when in doubt, check your EFORT documentation or contact us. Henghuan is an independent service provider, not affiliated with or endorsed by EFORT.