Meters and troubleshootingQuestion 1126 of 1506

How is a current transformer connected to the line it measures?

Its primary is in series with the line.
Its primary is in parallel with the line.
Its secondary is in parallel with the line.
It is connected across a fuse.

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Correct answer: Its primary is in series with the line.

A CT measures the line current, so the primary carries that current, in series.

Source: Lessons in Electric Circuits II: AC (Kuphaldt), 10.7: Special Transformers and Applications

Questions last reviewed: 18 October 2026

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