Refer to the drawing of a valve motor control circuit (see figure below) for a valve that is currently fully closed 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 OPEN.
Two seconds later, after verifying the valve is opening, the operator releases the control switch.
Which one of the following describes the alarm response after the control switch is released?
A. The alarm will activate after approximately 8 seconds.
B. The alarm will not activate until additional operator action is taken.
C. The alarm will remain activated for approximately 8 seconds, and then deactivate.
D. The alarm will remain activated until additional operator action is taken.
Show Answer
Answer: D
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