Refer to the drawing of a valve motor control circuit (see figure below) for a valve that is currently fully open and has a 10-second stroke time.
Note: Limit switch (LS) contacts are shown open regardless of valve position, but relay contacts are shown open/closed according to the standard convention for control circuit drawings.
The operator takes the control switch to CLOSE momentarily and the valve begins to close.
Five seconds later, the operator takes the switch to OPEN momentarily and then releases the switch.
Which one of the following describes the valve response after the switch is released?
A. The valve will stop closing and remain partially open.
B. The valve will stop closing and then go fully open.
C. The valve will close fully and remain fully closed.
D. The valve will close fully and then go fully open.
Show Answer
Answer: C
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