Refer to the drawing of a valve motor control circuit (see figure below).
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.
If the valve is currently closed, when will the alarm actuate?
A. As soon as PB2 is pushed.
B. Ten seconds after PB2 is pushed if the valve is still closed.
C. Immediately upon pushing PB2 and for the next 10 seconds if the valve remains closed.
D. Ten seconds after PB2 is pushed if the valve is still stroking open.
Show Answer
Answer: B
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