Retro C Calibration Will Not Hold or Changes After Restart

Use this guide when an axis can be calibrated but later returns to the wrong position, loses its setting after a restart, requires frequent recalibration, or produces different measurements each time it returns to the same command.

Applicability

Field	Detail
Product	Retro C
Subsystem	Carriage, angle, centerline, horizontal conveyor, or material-feed positioning
Hardware generation	All Retro C generations
Skill level	Maintenance technician working with Enventek Support for software-setting changes
Lockout/tagout	Required before inspecting encoders, chains, slides, couplings, brakes, shafts, or mechanical stops
Estimated time	20–45 minutes for diagnosis
Tools or parts	Accurate measuring tool, paint marker if approved, and the applicable calibration reference

Before You Begin

Do not begin with another full calibration. First identify whether the problem is a repeatability failure, a mechanical shift, unstable encoder feedback, a power interruption, or a setting that was not saved. Recalibrating an unstable mechanism can temporarily hide the cause and make later diagnosis harder.

Record:

• The affected movement.
• Commanded and measured positions.
• Whether the error is always in the same direction.
• Whether the error appears immediately, after several cycles, or only after restart.
• Any encoder, stall, overrun, or drive message.
• The last repair, collision, obstruction, or power loss.

Find the Type of Calibration Loss

1. Test repeatability before changing calibration

Move the affected axis away from a known reference and command it back through the normal controlled procedure. Repeat this several times without editing the calibration value. Measure from the same points each time.

• Same measured position every time, but the displayed value is wrong: calibration or saved configuration may be incorrect.
• Different measured position on repeated returns: investigate mechanical movement or encoder feedback before calibrating.
• Correct until restart, then wrong: confirm that the setting was saved and that startup completed without a power or storage problem.

Use the machine or facility tolerance approved for that movement. Do not invent a tolerance from a different axis.

2. Inspect for slipping or movement under load

Lock out the machine and inspect the affected encoder coupling, collar, set screw, sprocket, chain, gearbox connection, brake, and mounting hardware. Look for polished shaft marks, cracked couplings, loose fasteners, chain slack, or a component that can rotate independently of its shaft.

If permitted, place alignment marks across coupled parts. After reinstalling guards and performing a controlled movement, lock out again and confirm that the marks have not shifted.

3. Check for binding or mechanical stops

Debris, dry or tight slides, misalignment, excessive chain tension, and contact with a mechanical stop can prevent the axis from reaching the same position consistently. Correct the mechanical cause before recalibrating.

For an angle or centerline that stalls or reaches a stop, use Recover and Recalibrate a Stuck Angle or Centerline. For carriage hunting or length drift, use Carriage Stalling, Hunting, or Losing Length After Calibration.

4. Verify encoder feedback

During a controlled manual movement, confirm that the displayed count changes smoothly, in the correct direction, and returns to a consistent value. A count that jumps, freezes, reverses, or changes while stationary must be corrected before calibration.

• Use Retro C Encoder Counts Move in the Wrong Direction for reversed feedback.
• Use Encoder Unplugged Error: Diagnosis and Recovery for a disconnected or faulted encoder.
• Use Encoder Wiring Diagram when an approved wiring check is required.

5. Review the power-loss history

If power was lost while the saw was moving, compare all affected positions before running production. Determine whether the problem affects one axis or several systems. Use Recover Retro C After an Unexpected Power Loss for the controlled recovery sequence.

6. Recalibrate only the affected movement

Once mechanical movement and encoder feedback are stable, follow the article for that movement. A full saw calibration is not required when only one verified movement is out of calibration. If several unrelated positions changed at the same time, contact Enventek Support before overwriting multiple reference values.

For the full procedure, use Full Saw Calibration.

7. Verify before and after restart

After saving the calibration, test the affected movement repeatedly. Record the displayed and measured result, then restart through the approved procedure and perform the same test again. This separates an unsaved setting from a mechanical or feedback problem.

What Correct Looks Like

• The axis returns to the same measured position on repeated commands.
• Encoder counts move smoothly in the correct direction.
• Couplings, collars, chains, brakes, and mounting hardware do not shift.
• The saved position remains correct after an approved restart.
• No encoder, stall, overrun, or drive warning returns.
• A controlled verification cut or measurement meets the approved tolerance.

When to Contact Enventek

Contact Enventek Technical Support if several unrelated calibrations change together, the displayed value is unstable, a setting will not remain saved, or the correct tolerance/reference is unknown. Provide the movement name, repeated measurements, before-and-after restart results, encoder status, and the last power or mechanical event.

Search Terms

saw out of calibration, calibration won’t hold, loses calibration, wrong after restart, position drift, length changes, needs calibration again