Alarm limits and trends are defined against service definitions. They permit the entry of process or equipment measurements that need to be taken while carrying out an inspection.
The lower alarm limit defines the minimum reading that is acceptable; the upper alarm defines the maximum acceptable reading. The trend indicates the largest change in reading between each subsequent measurement.
Alarms and trends can only be specified against service definitions that have an order type that permits multiple operations to be assembled under the same work order. If the order type does not permit this, these fields will be hidden.
A service definition associated with a bearing inspection may specify that the temperature should be between 50 degrees (lower) and 75 degrees (upper), and should not increase more than 2 degrees per month (the trend and frequency).
Clearly if the temperature is above the maximum, there is a problem (maybe lack of lubrication, misalignment etc). If the temperature trend is increasing more than 2 degrees per inspection (indicating an increased failure probability), there could also be a problem.
When an operation is fed back, a reading entry will be requested. The entered reading will then be compared with the expected values. If outside the tolerances, a service definition will be automatically produced to investigate the problem. The equipment owner will also be electronically informed.