During his dutytime, for certain reason if he wants to take a short leave, he must be approved by the duty engineer and concerned supervisor.
在值班时间内因故离开岗位时要得到值班工程师和有关主管的批准。
2
Describing the specialities of the starting motor brushes are of short-timeduty system, big current density and the contact voltage drop must be as small as possible.