Description: time period during which all the performance requirements are met; Name: usefull life
Description: Time interval from first use until the instant when a limiting state is reached ; Name: useful life
Description: permanent operation, short-term operation or periodic operation characterized by one of more loads and which remains unchanged during a certain period, or, in the case of non-periodic operation, where the load and speed generally change within the permissible operating range; Name: Operation type time sequence of the drive