In conventional valves, which component is used to move the spool?
A. torque motor
B. mechanical servo valve
C. solenoid
D. all the above
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What is the advantage of DC solenoid coils?
A. DC solenoid coils have high rush in current
B. DC solenoid coils have constant level of current
C. DC solenoid coils have rating of 220 V DC
D. all the above
In which control valve energy consumption reduces as load decreases?
A. conventional direction control valve
B. proportional direction control valve
C. both a and b
D. none of the above
Which of the following is a characteristic of servo valve?
A. open loop system
B. closed loop system
C. less contamination
D. all the above
What is the function of a pressure switch or relay?
A. pressure switch is used to start a motor
B. pressure switch is used to stop a motor
C. pressure switch is used to deenergize a solenoid
D. all the above
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