Meters and troubleshootingQuestion 748 of 1506

Why is the voltmeter in a thermocouple circuit made with very high resistance?

To raise the thermocouple voltage
To let more current flow through the thermocouple wires
To avoid voltage drops along the thermocouple wire that cause errors
To make the thermocouple hotter and raise the voltage it makes

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Correct answer: To avoid voltage drops along the thermocouple wire that cause errors

Only a few millivolts are made, so even a small drop is a big error. The meter should draw almost no current.

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

Questions last reviewed: 18 October 2026

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