Renishaw ATOM Installation Manual page 50

Fault Cause
LED on the readhead appears
AGC is switched on and the signal
white with flashes of other level is < 70%
colours as the readhead is
moved along the axis
LED on the readhead is double The readhead is not seeing
flashing blue even after moving
a reference mark
it past the reference mark
several times
No reference mark output
Reference mark is not Only the chosen reference mark
repeatable that has been used in the calibration
sequence is repeatable, other reference
marks may not be phased
LED on the readhead is
The reference mark is not phased
flashing red or blank over
the reference mark
Multiple reference marks output Unused reference marks have not been
deselected or FPC is damaged
50 ATOM linear encoder system
Possible solutions
• Check the readhead optical window and scale are clean and free from contamination.
• Restore factory defaults (page 47) then check the LED is green along the full axis and recalibrate the system (page 45).
If it is not green check the alignment of the readhead.
• Ensure you are moving the readhead past your chosen reference mark several times.
• Check the scale / readhead orientation.
• Check the scale / readhead alignment.
• Check the readhead optical window and scale are clean and free from contamination.
• Check that the readhead variant is the correct type for the chosen scale (see the ATOM
data sheet (Renishaw part no. L-9517-9563) for details of readhead configuration).
• Ensure you are not moving the readhead too fast during calibration mode (maximum speed < 100 mm / sec).
• Calibrate the system (page 45)
• If the system completes calibration mode, then it has successfully seen and calibrated the reference mark. If
you still cannot see a reference mark then check the system wiring.
• If the system does not calibrate the reference mark (LED on the readhead double flashes blue), see above for
possible solutions.
• Ensure you are using the reference mark that has been calibrated for referencing your system.
• The readhead bracket must be stable and not allow any mechanical movement of the readhead.
• Check any unused reference marks have been deselected.
• Clean the scale and readhead optical window and check for damage then recalibrate the system over the chosen
reference mark.
• Ensure you are using the reference mark that has been calibrated for referencing your system as only this reference
mark will be guaranteed to remain phased.
• The LED may flash blank or red when passing other reference marks if they have not been deselected (page 21).
• Clean the scale and readhead optical window and check for scratches then recalibrate the system over the chosen
reference mark (page 45).
• All unused reference marks should be deselected (page 21) as only the calibrated reference mark will be repeatable.
• Check alignment of deselection stickers.
• Replace damaged FPC (if applicable).
™ miniature encoder system