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Calibration of Thermistors for Precision Temperature Measurements

정밀온도측정을 위한 서미스터 교정

  • Gam, Kee-Sool (Division of Physical Metrology, Korea Research Institute of Standards and Science) ;
  • Kim, Yong-Gyoo (Division of Physical Metrology, Korea Research Institute of Standards and Science) ;
  • Yang, In-Seok (Division of Physical Metrology, Korea Research Institute of Standards and Science)
  • 감기술 (한국표준과학연구원 기반표준본부) ;
  • 김용규 (한국표준과학연구원 기반표준본부) ;
  • 양인석 (한국표준과학연구원 기반표준본부)
  • Received : 2011.08.11
  • Accepted : 2011.09.02
  • Published : 2011.09.30

Abstract

We demonstrated that high-stability thermistors can be calibrated with an uncertainty less than 1 mK, if the error due to the heat conduction is minimized. We first investigated the effect of the self-heating of typical thermistor probes to see how accurate we need to determine the effect of self-heating. We, then, calibrated thermistors and fitted the results using various modeling equations. We found out that the heat conduction is an important factor in achieving the calibration uncertainty under 1 mK for thermistors when the diameter of the probe is as thick as 10 mm. Therefore, we controlled the room temperature within $0.5^{\circ}C$ to minimize the heat conduction error during the calibration. The calibration with an uncertainty below 1 mK was possible when the stabilization time for each calibration was long enough to obtain a good thermal equilibrium.

Keywords

References

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