Temperature and Pressure Coefficients of Thomas 1 Ohm Resistors

Published

August 1, 2006

Author(s)

George R. Jones Jr., Randolph Elmquist

Abstract

In preparing to move the precision 1 ohm measurement service to the new Advanced Measurement Laboratory (AML) in the spring of 2004, staff at the National Institute of Standards and Technology (NIST) first assembled a second precision 1 ohm measurement system in the AML. This allowed for the calibration service to continue uninterrupted during the transition. Both systems are fully automated and all calibrations include the measurement of laboratory ?influence factors? including the bath temperature and atmospheric pressure. Over the past year additional components have been added to these two systems which enable NIST to characterize the behavior of precision 1 ohm 'nresistors over a wide range of temperatures and pressures. These modifications include both an auxiliary thermal oil bath and a pressure chamber, each having capacity for up to three precision 1 ohm resistors. Approximately twenty resistors have gone through a battery of thermal and pressure tests at temperatures from 20 ?C to 26 ?C and at pressures from 80 kPa to 110 kPa. Tests have shown that some Thomas-type resistors experience non-reversible shifts in their values due to pressure changes.

Proceedings Title

NCSLI Workshop & Symposium

Conference Dates

August 6-10, 2006

Conference Location

Nashville, TN, USA

Conference Title

NCSL International Workshop and Symposium

Pub Type

Conferences

Download Paper

Local Download

Keywords

coefficients, precision, pressure, resistors, temperature

Citation

Jones Jr., G. and Elmquist, R. (2006), Temperature and Pressure Coefficients of Thomas 1 Ohm Resistors, NCSLI Workshop & Symposium, Nashville, TN, USA, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=32289 (Accessed October 8, 2025)