Temperature Measurement · Glossary

What is Thermocouple Extension Cable?

extension and compensating cableTemperature Measurement

Thermocouple extension cable carries the thermocouple signal to the instrument using wires that match the thermocouple characteristics.

Thermocouple Extension Cable Explained

Extension cable uses the same alloys as the thermocouple. Compensating cable uses cheaper alloys that match the output only over a limited temperature range, mainly for noble metal types.

Using copper cable from the head to the instrument moves the cold junction to the head, which is not measured, so large errors appear.

Calculators for Thermocouple Extension Cable

CalculatorThermocouple CalculatorFree online calculator with formula and worked example.CalculatorThermocouple TableFree online calculator with formula and worked example.

Free Tools

ToolThermocouple Color CodesFree interactive tool on instrumentationblog.in.

Frequently Asked Questions

What is Thermocouple Extension Cable?

Thermocouple extension cable carries the thermocouple signal to the instrument using wires that match the thermocouple characteristics.

How do I identify the cable type?

By the colour code of the standard used, such as IEC 60584-3, and the marking on the sheath.

Can I join extension cable with copper terminals?

Avoid it in a temperature gradient; use thermocouple terminals or keep both joints at the same temperature.

Learn more on the blog

Thermocouple and RTD installation precautions

A practical guide on instrumentationblog.in with more detail on thermocouple extension cable and how it is applied on real plants.

Read Full Article

More Temperature Measurement Terms

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