WEBVTT

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Why is a transformer core normally earthed

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at one intended point?

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The connection controls the core's electrical potential.

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An unintended second contact can close a

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loop through the core,

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frame and tank.

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When changing magnetic flux links that loop,

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circulating current can produce local heating.

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A metal chip,

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displaced sheet or damaged insulation can create

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that extra contact.

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Keep the build clean and protect core-to-frame

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insulation.

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Before energization, use the approved inspection and

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test procedure, with the results recorded.

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Compare the condition after transport with the

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factory baseline.

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One intended connection,

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protected insulation, and verified assembly:

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that is the control.