Here is a basic outline of a Preventive Maintetance for your Lensmeter:
Check all electrical, mechanical & optical Assemblies.
Inspect eyepiece and internal reticles.
Check table operation.
Check marking pen operation.
Inspect target for correct alignment.
Check optical carriage performance.
Check lamp house, socket & switch.
Ensure correct lamp is in housing to prevent melting.
Check power and axis dials for correct movement.
Check swivel mechanism for correct operation.
Verify correct calibration using Gauge Master or other certified lens set.
Clean all optics and other surfaces.