preventive maintenance

regular maintenance and repairs in order to prevent serious deterioration

Preventive maintenance (PM) has the following meanings:The care and servicing by personnel for the purpose of maintaining equipment and facilities in satisfactory operating condition by providing for systematic inspection, detection, and correction of incipient failures either before they occur or before they develop into major defects. Maintenance, including tests, measurements, adjustments, and parts replacement, performed specifically to prevent faults from occurring.
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1. The care and servicing by personnel for the purpose of maintaining equipment and facilities in satisfactory operating condition by providing for systematic inspection, detection, and correction of incipient failures either before they occur or before they develop into major defects. [JP1] 2. Maintenance, including tests, measurements, adjustments, and parts replacement, performed specifically to prevent faults from occurring. (188 )

(PM) To bring down a machine for inspection or test purposes.
See provocative maintenance, scratch monkey.
(1995-02-15)

maintenance preformed to equipment to try to prevent future random failures of the equipment or cleans to improve the quality of the equipment output. Preventive maintenance is performed on a scheduled basis based on elapsed time, number of runs or number of wafers processed.

see Preventive Maintenance