Robotics in Manufacturing

Mastering & calibration

Mastering After Motor Replacement

For a maintenance technician who has just replaced an axis motor or pulsecoder and needs to restore accurate positioning before returning the robot to production. Single-axis mastering is the typical remaster path for this case.

Intermediate~45 min9 steps
  1. Step 1.

    Support the arm before any brake release

    Before releasing a brake for install or checks, support the arm on a solid support. The arm can fall if it is not supported.

    Caution: Never release a brake on a gravity-loaded axis without a solid mechanical support in place.

  2. Step 2.

    Power up and clear alarms

    Turn on the controller and confirm the new motor communicates. Clear any initial encoder alarms and perform a pulse reset if required for the axis.

  3. Step 3.

    Confirm the axis moves correctly

    In T1 low-speed joint jog with the deadman held, verify the axis moves in the expected direction without unusual noise or resistance.

    Caution: Keep the cell clear of other personnel while jogging.

  4. Step 4.

    Jog to the mastering position

    Bring the replaced axis to the mastering position appropriate for the method you'll use.

  5. Step 5.

    Perform single-axis mastering

    On the pendant, press MENU, then 0 NEXT, then 6 SYSTEM, and select Master/Cal. Choose item 5 SINGLE AXIS MASTER. The screen lists each axis with columns ACTUAL POS, MSTR POS, SEL, and ST. For the replaced axis, set SEL to 1 (if the axis has an interaction pair that must be mastered together, set SEL to 1 for both). Enter the MSTR POS for that axis, which is usually 0. Press F5 EXEC to run the single-axis master. SEL returns to 0 and ST updates when it's done.

  6. Step 6.

    Calibrate and power-cycle

    Run CALIBRATE, then restart the controller so the new mastering takes effect.

  7. Step 7.

    Run a full range check

    Jog the axis through its full range at low speed to confirm no unexpected limits or alarms.

  8. Step 8.

    Verify against a production point

    Run the robot to a known taught position and confirm it matches expected accuracy.

  9. Step 9.

    Back up the updated mastering data

    On the pendant, go to File, press F4 BACKUP, and save System files. Mastering data is stored as SYSMAST.SV.

Common questions

How long does Mastering After Motor Replacement take?
Mastering After Motor Replacement is rated Intermediate and takes about 45 minutes across 9 steps.
What tools do I need?
You will need Teach pendant, Mechanical support for the affected arm segment.
What should I do before starting?
New motor or pulsecoder is mechanically installed and correctly wired.. Brake and encoder cabling verified before power-up.. The affected axis has been supported so it cannot fall..
What is the first step?
Support the arm before any brake release. Before releasing a brake for install or checks, support the arm on a solid support. The arm can fall if it is not supported.

Attribution

Procedure steps on this page are checked against the site's editorial safety rules and manufacturer-manual sourcing standards.

Last reviewed: 2026-07-21.

Edited by Mike Ramsey / Reliable Media.Editorial process