![]() Each measurement point is based on the average or mean of 30 or more readings or samples. Measurement noise is the uncertainty caused by the noise or instability of the measurement readings. Note: Each uncertainty is rounded to two decimal places after calculations are applied. Reference junction accuracy (for UUT – Type S) Reference junction accuracy (for reference probe)ġ586A readout accuracy (for UUT – Type S) Measurement noise/stability of UUT (n≥30)ġ586A readout accuracy (for reference probe) Measurement noise/stability of reference (n≥30) Thermocouple calibration system uncertainty evaluation at 1000 ☌ Type B standard uncertainties More will be explained in the "Combining uncertainties" section of this document. For example, in most cases, k = 2 corresponds to a 2-sigma or 95 % confidence interval. The k value corresponds to a confidence interval. Or, an uncertainty is divided by a conversion divisor to estimate its standard uncertainty (k=1) value. The difference between standard and expanded is that the standard uncertainty has been multiplied by some coverage factor, typically stated in the form of a value of k, to become an expanded uncertainty. The following uncertainty analysis lists each uncertainty in both standard and expanded form. This uncertainty analysis is comprehensive but is simplified for a general technical audience so it may be important to consult with your local NMI (National Metrology Institute) for further details or with your accreditation body (for accredited calibration labs). Each uncertainty has been given a code and a corresponding discussion is provided. It offers one method for aggregating some of the most important contributors to the system uncertainty. Temperature source: 9118A Thermocouple Calibration Furnaceįigure 1 presents a sample uncertainty budget.Readout: 1586A Super-DAQ Precision Temperature Scanner with DAQ-STAQ Multiplexer.Reference probe: 5650 Type S Thermocouple with reference junction.This section gives an example of how to prepare an uncertainty budget for a system comprised of the following equipment when calibrating a thermocouple at 1000° C: There are several calibration uncertainties to be evaluated in determining the total uncertainty of a thermocouple calibration system.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |