单项选择题
A probable cause for a turbo generator tripping out on overspeed is a sudden（）
A.loss of field excitation B.total loss of load C.large increase in load D.loss of steam pressure
单项选择题 All of the following operating characteristics are listed on the name-plates of motors used aboard ship except the（）
单项选择题 When would you ground an electric hand tool?（）
单项选择题 The load between two steam-driven alternators operating in parallel may be adjusted by varying （）
