How to Determine Thermocouple System Accuracy To determine your system accuracy when you have a separate meter and probe, add the tolerance of the meter to the tolerance of the probe. The diagram at right shows the accuracy versus temperature for a typical thermocouple meter and probe. For example, using the diagram, the meter error at 250°C is ±0.5°C and the probe error at 250°C is ±1.0°C, thus the system accuracy would be ±1.5°C or better. The result is often conservativethe actual system accuracy is usually better. Glass thermometers, labels, paints, bimetal thermometers, hand-held infrared thermometers, and digital indicators include a general system accuracy statement. National Institute of Standards and Technology (NIST) documentation gives you the actual system accuracy. Knowing the actual system accuracy gives you the ability to compensate or calibrate your instruments measurements for greater accuracy. View our complete listing of our NIST temperature calibration services | |