单项选择题
A.a closed loop control system B.an open loop control system C.a boiler control system D.a steering gear control system
This arrangement is （） if the elements are directly con...
单项选择题This arrangement is （） if the elements are directly connected to one another and the control action takes place without human involvement.
A.a manual closed loop B.a manual opened loop C.an automatic closed loop D.an automatic opened loop
Bourdon Tube is probably the most commonly used （） meas...
单项选择题Bourdon Tube is probably the most commonly used （） measuring instrument.
A.the absolute pressure B.the gauge pressure C.the vacuum pressure D.the differential pressure
Movement of the diaphragm or bellows is （） by a linkage...
单项选择题Movement of the diaphragm or bellows is （） by a linkage to a needle or pointer display to indicate the differential pressure between two sides of the diaphragm or bellows.
A.measured B.recorded C.transferred D.controlled
