PRACTICAL LIMITS OF MEASUREMENT UNCERTAINTIES IN CALIBRATION OF STANDARD PLATINUM RESISTANCE THERMOMETERS BY COMPARISON
Abstract
Usually, SPRTs are calibrated at fixed points, but due to the high cost of a primary realization of physical quantities and time needed for the calibration at fixed points, it can be reasonable to calibrate them by comparison at the highest level.<br />The calibration by comparison is a technique most widely used to calibrate measuring instruments, not only in industry but also in many secondary calibration laboratories. Calibration procedures of a typical secondary laboratory are based on the use of transfer standards, which are usually calibrated in a primary laboratory, thus providing traceability to (inter)national standards through a process of dissemination of a unit with an associated uncertainty.<br />The aim of the paper is to show that temperature calibrations by comparison, in the range from –95 °C up to 300 °C, can result in a calibration uncertainty (<i>k</i> = 2) of 0,005 °C, which is sufficiently low for many industrial applications and secondary calibration laboratories.
Event details
- Event
- XIX IMEKO World Congress
- Place
- Lisbon, PORTUGAL
- Time
- 6 September 2009 - 11 September 2009
- Website
- http://www.imeko2009.it.pt/