Meters are used by the system to schedule recurring maintenance work such as lubrication, visual inspections, and planned replacement. Meters may be set up to indicate calendar based time such as days, weeks, months, and years, but may also be defined as process meters such as run-time, number of operations and tonnage. The meter are used to hold both forecast and actual meter usage.
Meters-based maintenance schedules are most effective when the equipment's failure characteristics are condition-related, for example when deterioration is due to usage rather than time. Unlike with paper based control systems, using computer systems and advanced planning tools , it is now feasible to schedule regular maintenance work based on its actual usage. In seasonal operations, this reduces the amount of maintenance required off-season, when the equipment is not being used.
Meters can be linked to any level within the equipment structure although in most configurations, there will be a consistent set of meters at all levels.
Meter readings can be specified manually into the system or transferred automatically from the M3 manufacturing application. In the case of actual meter readings, the values then cascade down the structure to lower levels. Forecast meter readings are held only at the 'planning position' levels within the structure.
Different types of meters can be assigned to equipment for planning purposes. For example, a pump could have both a calendar meter of weeks and an operation meter of running hours. When scheduling maintenance, these meters will ‘compete’ so an inspection can be generated every 200 running hours or once a month, whichever comes first (the work order request generated by this process will indicate which meter actually triggered the service on this occasion).
A special type of meter called absolute meter exists. In this case, the service linked to the meter is triggered when a particular event occurs. For example when the thickness of a set of brakepads is less than 4mm, then trigger a service to replace them.