Question 320Electricity & Electronics - QMED
70% to passAs shown in the illustration, assuming power is available at the control circuit, which listed action will occur FIRST when the "off-run" switch is placed in the "run" position? Illustration EL-0017
AThe disconnect switch (DS) contacts close.
BThe "OL" relay contacts close.
CThe contactor coil "M" energizes.
DThe main contacts
AI Explanation
The correct answer is C) The contactor coil "M" energizes. When the "off-run" switch is placed in the "run" position, the first action that will occur is the energization of the contactor coil "M". This is because the contactor coil is the first component in the control circuit that needs to be activated to allow the flow of power to the rest of the system. The disconnect switch (DS) contacts and the "OL" relay contacts will only close after the contactor coil "M" has been energized, as they are downstream components in the circuit. The other answer choices are incorrect because they represent actions that occur later in the sequence, after the contactor coil "M" has been energized.
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