Question 234Electricity & Electronics - 1st Asst/Chief

70% to pass

What is the function of a shading coil as used in an AC magnetic controller?

Aprevent flux buildup in the operating coil
Breduce chatter and noise in the contactor
Cenergize the operating coil and 'pull in' the contacts
Deliminate arcing when the contacts close
AI Explanation

The correct answer is B) reduce chatter and noise in the contactor. The shading coil in an AC magnetic controller is used to reduce chatter and noise in the contactor. The shading coil creates a phase shift in the magnetic field, which helps to dampen the vibrations and prevent the contacts from chattering when they close. This ensures smooth and quiet operation of the contactor. The other options are incorrect because: A) the shading coil does not prevent flux buildup in the operating coil, C) the shading coil does not energize the operating coil or pull in the contacts, and D) the shading coil does not eliminate arcing when the contacts close.

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