Meters and troubleshootingQuestion 747 of 1506

In a thermocouple circuit, what causes the reference (cold) junction?

The power supply of the meter and its internal fuse
The ground connection at the far end of the long cable
A broken wire somewhere in the length of the cable
Where the metals join the meter leads

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Correct answer: Where the metals join the meter leads

Any joint of dissimilar metals makes a voltage, and one such joint is always at the instrument.

Source: Lessons in Electric Circuits I: DC (Kuphaldt), 9.5: Thermocouples

Questions last reviewed: 18 October 2026

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