The time used to test the machine or system to insure that no faults exist or malfunctions are present by using special diagnostic routines for circuit testing or to discern status of conditions or components.

• 用于测试机器或系统，保证其无故障运行或无工作不正常所需的时间，其间采用特殊诊断例行程序来检测电路，判定条件状态或部件状态。