Thermocouple Calibration - An Act of Fine Tuning

2008-10-27 12:15:42

( Business )



In electrical engineering and industry, thermocouples are a widely used type of temperature sensor and can also be used as a means to convert thermal potential difference into electric potential difference. They are cheap and interchangeable, have standard connectors, and can measure a wide range of temperatures. The main limitation is accuracy with system errors of less than one degree Celsius can be difficult to achieve.

Thermocouples measure the temperature difference between two points, not absolute temperature. In traditional applications, one of the junctions — the cold junction — was maintained at a known (reference) temperature, while the other end was attached to a probe. A thermocouple can produce current, which means it can be used to drive some processes directly, without the need for extra circuitry and power sources. Thermocouples can generally be used in the testing of prototype electrical and mechanical apparatus. For example, switch gear under test for its current carrying capacity may have thermocouples installed and monitored during a heat run test, to confirm that the temperature rise at rated current does not exceed designed limits.

As with other equipment, thermocouple needs calibration. There are thermocouple calibration services for all commonly used types of thermocouples and thermocouple materials. The temperature range for a particular calibration depends on the type of wire or thermocouple. There is also thermocouple calibration software available to perform multipoint system calibration on any measurement system and any thermocouple type, improving accuracy by up to 400%.

It is a given fact that instruments such as a thermocouple needs to be calibrated, but there is also a question of when to perform equipment calibration. Calibration frequencies to consider include manufacturer-recommended calibration interval, before and after a major critical measuring project, per requirements, annually or biannually.

Thermocouple calibration is a form of quality assurance and it ensures safety and reliability of the instrument to get the accurate test results you need.


All rights Reserved © Tradenet Services srl
Do not duplicate or redistribute in any form.