25 MaintenanceType 
25.3 Interval
Description: Regular interval between two maintenances. Use of AnalogItemType for flexible units (e.g. months, days, operating hours, m).
Example: 1000 h
Online versions of OPC UA specifications and information models.
Description: Regular interval between two maintenances. Use of AnalogItemType for flexible units (e.g. months, days, operating hours, m).
Example: 1000 h