Refer to the drawing of a valve motor control circuit (see figure below).
Pushbutton PB2 was depressed to open the valve, and the current contact and pushbutton status is as shown with the following exceptions:
LS1 is closed.
LS3 is closed.
#1 contact is closed.
#2 contact is closed.
Which one of the following describes the condition of the valve and its control circuit?
A. The valve is closed and the valve motor circuit has just been energized to open the valve.
B. The valve is closed and an open demand signal has existed for at least 10 seconds.
C. The valve is partially open and the valve motor circuit is deenergized because PB2 was prematurely released.
D. The valve is partially open and an open demand signal has existed for at least 10 seconds.
Show Answer
Answer: B
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