Methods for assessing homogeneity and interchangeability of thermocouple wires

✍ Scribed by L.L. Sparks; R.L. Powell

• Book ID: 103050903
• Publisher: Elsevier Science
• Year: 1972
• Tongue: English
• Weight: 334 KB
• Volume: 12
• Category: Article
• ISSN: 0011-2275
• DOI: 10.1016/0011-2275(72)90136-1

✦ Synopsis

Chemical and physical imperfections and inhomogeneities in thermocouple wire cause spurious voltages whenever these imperfections are subjected to temperature gradients. Thermocouple wires from different spools (or even from widely separated lengths on the same spool) usually exhibit significant differences in their thermoelectric properties. For accurate thermometry it is important to know the range of spurious voltages to be expected from a specific material Simple laboratory methods are described for determining the effects of short-range inhomogeneities or long-range variations. Examples of results from tests are discussed in order to point out both the usefulness and the limitations of the methods.