산업용 백금저항온도계를 위한 향상된 내삽식
Improved Interpolating Equation for Industrial Platinum Resistance Thermometer
2
조회
0
다운로드
1
인용
0
참고문헌
키워드
초록
We propose an improved interpolating equation to express temperature-resistance characteristics for modern industrial platinum resistance thermometers (PRTs). Callendar-van Dusen equation which has been widely used for platinum resistance thermometer fails to fully describe temperature characteristics of high quality PRTs and leaves systematic residual when the calibration point include temperatures above 300 °C. Expanding Callendar-van Dusen to higher-order polynomial drastically improves the uncertainty of the fitting even with reduced degrees of freedom of the fitting. We found that in the fourth-order polynomial fitting, the third-order and fourth-order coefficients have a strong correlation. Using the correlation, we suggest an improved interpolating equation in the form of fourth-order polynomial, but with three fitting parameters. Applying this interpolating equation reduced the uncertainty of the fitting to 32 % of that resulted from the traditional Callendar-van Dusen. This improvement was better than that from a simple third-order polynomial despite that the degrees of the freedom of the fitting was the same.
Abstract
We propose an improved interpolating equation to express temperature-resistance characteristics for modern industrial platinum resistance thermometers (PRTs). Callendar-van Dusen equation which has been widely used for platinum resistance thermometer fails to fully describe temperature characteristics of high quality PRTs and leaves systematic residual when the calibration point include temperatures above 300 °C. Expanding Callendar-van Dusen to higher-order polynomial drastically improves the uncertainty of the fitting even with reduced degrees of freedom of the fitting. We found that in the fourth-order polynomial fitting, the third-order and fourth-order coefficients have a strong correlation. Using the correlation, we suggest an improved interpolating equation in the form of fourth-order polynomial, but with three fitting parameters. Applying this interpolating equation reduced the uncertainty of the fitting to 32 % of that resulted from the traditional Callendar-van Dusen. This improvement was better than that from a simple third-order polynomial despite that the degrees of the freedom of the fitting was the same.
참고문헌 (10)
- 감기술, "백금저항온도센서를 이용한 국가교정기관의 교정능력 평가 및 실험방법", 센서학회지, 14(4), pp.231~236 (2005), 한국센서학회
- J. V. Nicholas, "Traceable Temperatures, 2nd Ed", pp.206~207 (2001), John Wiley & Sons
- H. Preston-Tomas, "The international temperature scale of 1990 (ITS-90)", Metrologia, 27(1), pp.3~10 (1990)
- "ASTM Standard E 1137", E 1137M - 04, Standard specification for industrial platinum resistance thermometers, 2004
- "IEC 60751, Industrial platinum resistance thermometers and platinum temperature sensors", International Electrotechnical Commission, ~ (2008)
- "지시 저항 온도계", 한국산업규격 KSC 1604, ~ (1987)
- "JIS C 1604, Resistance thermometer sensors", Japanese Standards Association, ~ (1997)
- "International Recommendation OIML R 84, Platinum, copper, and nickel resistancethermometers (for industrial and commercial use)", International Organization of Legal Metrology, ~ (2003)
- L. Crovini, "Accurate thermometry by means of industrialplatinum resistance thermometers", Measurement, 10(1), pp.31~38 (1992)
- P. Marcarino, "ITS-90 approximation by means of nonstandard platinum resistance thermometers", TEMPMEKO-2001: 8th symposium on temperature and thermal measurement in industry and science, Berlin, pp.85~90 (2001)