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ISSUE — Bolt X Cannot Enable After Power Loss — Zero Position Reset Required

CONFIRMED RESOLVED BOTH BOLT X

Summary

After power loss mid-move, Bolt X (Yaskawa) cannot re-enable and the teach pendant reports "Cannot reset major alarm". Unlike the Staubli Bolt which uses absolute encoders, the Yaskawa requires a teach pendant zero position reset procedure before it can re-enable. The full procedure is in the Bolt X Quick Start Guide starting at page 37.

Symptoms

  • Robot will not enable on either Flair or the teach pendant after a power loss mid-move
  • Teach pendant shows: "Cannot reset major alarm"
  • Robot was at approximately 77% through a move when power was lost
  • Nothing in the arm is over limit; no E-stop is pressed
  • Power cycling and switching power sources does not resolve it

Systems Affected

  • Bolt X (Radu Stefan Fulga — confirmed)
  • Likely applicable to other Yaskawa-based systems

Software Environment

BOTH

This is a hardware/controller state issue — not software-version dependent.

Root Cause

Bolt X (Yaskawa) uses a teach pendant-managed zero calibration that can be invalidated if the robot loses power mid-motion. Unlike the Staubli Bolt which uses an absolute encoder (and doesn't need re-zeroing after power loss), the Yaskawa requires a zero-position reset procedure via the teach pendant before it can re-enable.

Solutions

Solution A — Re-set zero position via the teach pendant (QSG procedure)

CONFIRMED BOTH

Contributor(s): Gordon Eschke — 2022-07-03

Steps

  1. Refer to the Bolt X Quick Start Guide — page 37 onwards for the full zero position reset procedure.
  2. The procedure uses the teach pendant to physically move each axis to its zero reference position.
  3. After the zero position is confirmed, the major alarm should clear.
  4. The robot should then be able to enable normally.

The QSG is available at: Bolt X Quick Start Guide — printed page 37

Notes

"@Radu Stefan Fulga you will need to re-set zero position. This is covered in the QSG." — Gordon Eschke

"Ok, so, if the robot doesn't enable for me to move the motors with the teach pendant... How do I do the 0 position?" — Radu Stefan Fulga

The zero reset procedure requires the robot to be moveable with the pendant. If the pendant reports "cannot reset major alarm" and the robot will not move at all, contact MRMC support as there may be a deeper hardware fault.

Timeline

Event Date Contributor
Reported + resolved via QSG procedure 2022-07-03 ~ Radu Stefan Fulga, Gordon Eschke

Official Documentation

Document Section Notes
Bolt X Quick Start Guide — printed p.41: Bolt X recalibration Appendix 2, p.41 Bolt X Recalibration procedure

Flair Classic Manual — Ch.21 Zeroing — p.307

Flair 7 Manual — Ch.18 Zeroing — p.257

WhatsApp Excerpts

[3/7/2022, 3:25:50 am] ~ Radu Stefan Fulga: Robot will not enable on two different power sources that have been checked to work with the Bolt X. Move was at 77% speed. We tried powering everything on and off multiple times on both power sources. We lost power. Nothing in the arm is over limit, no estop is pressed.

[3/7/2022, 3:25:53 am] ~ Radu Stefan Fulga: The reset button says "cannot reset major alarm"

[3/7/2022, 3:25:53 am] ~ Radu Stefan Fulga: Robot will not enable on teach pendant either

[3/7/2022, 3:35:30 am] Gordon Eschke: you will need to re-set zero position. This is covered in the QSG

[3/7/2022, 3:40:45 am] Gordon Eschke: [QSG link] page 37 onwards

[3/7/2022, 4:20:07 am] ~ Radu Stefan Fulga: Ok, so, if the robot doesn't enable for me to move the motors with the teach pendant... How do I do the 0 position? :D

Revision History

Date Change Editor
2026-05-24 Initial extraction Tom D / Claude Code