【判断题】【消耗次数:1】
电气设备的金属外壳,必须按规定进行接零或接地保护。
正确
错误
参考答案:
复制
纠错
相关题目
【判断题】 一切电气设备的金属外壳接地是避免人身触电的保护接地。
①  正确
②  错误
【单选题】 配电箱的金属材料,铁制盘及电气的金属外壳,可不做保护接地(或保护接零)。( )
①  正确
②  错误
【判断题】 TN方式供电系统是将电气设备的金属外壳与工作零线相接的保护系统,称作接零保护系统,用?TN?表示。
①  正确
②  错误
【判断题】 保护零线应由工作接地线、总配电箱电源侧零线或总漏电保护器电源零线处引出,电气设备的金属外壳必须与保护零线连接
①  正确
②  错误
【单选题】 电气设备外壳接地属于( )。
①  工作接地
②  防雷接地
③  保护接地
④  大接地
【判断题】 接零保护指的是将用电设备的人体可触及的金属外壳通过接地线与用电设备电源的中性点(也称为供电系统的接零点)连接。
①  正确
②  错误
【判断题】 做防雷接地机械上的电气设备,保护零线必须同时作重复接地。
①  正确
②  错误
【判断题】 保护接零适用三相四线制中线接地系统中的电气设备,同一供电电路上不允许部分设备接地,部分设备接零。
①  正确
②  错误
【判断题】 桥式起重机所有的电气设备外壳均应接地
①  正确
②  错误
【判断题】 施工现场灯具金属外壳不应接保护零线
①  正确
②  错误
随机题目
【单选题】 It was for this reason ___ her uncle moved out of New York and settled down in a small village.
①  which
②  why
③  that
④  how
【单选题】 The car salesman took the customer for a driver in the new model in order to ___ its improved features.
①  advocate
②  demonstrate
③  exhibit
④  reveal
【单选题】 I caught a___ of the car before it disappeared around the bend.
①  glance
②  glimpse
③  glare
④  stare
【单选题】 Alice ___her father that both she and her husband would be happy if he would live with them.
①  convinced
②  reinforced
③  pledged
④  required
【单选题】 Never in my wildest dreams ___ these people are living in such poor conditions.
①  I could imagine
②  ?could I imagine
③  ?I couldn’t imagine
④  ?couldn’t I imagine
【单选题】 It was ___ back home after the experiments.
①  not until midnight did he go
②  until midnight that he didn’t go
③  not until midnight that he went
④  until midnight when he didn’t go
【判断题】 Mark often attempts to excape to be fined whenever he breaks traffic regulations.
①  正确
②  错误
【单选题】 The patients believe that the doctor knows exactly how to put them ___.
①  right
②  correct
③  perfect
④  well
【判断题】 It was because he was too clumsy to drive a car that Jim hadnt learned to drive.
①  正确
②  错误
【单选题】 Half of the workers here ___ under 30 ___.
①  is/years
②  are/year old
③  is/years old
④  are/years of age