ASTM E2821-20 - Standard Specification for Compacted Mineral-Insulated, Metal-Sheathed Cable Used in Industrial Resistance Thermometers

1.1 This specification covers the requirements for compacted, mineral-insulated, metal-sheathed (MIMS) cables used to manufacture metal-sheathed, industrial resistance thermometers referred to in this document as Resistance Temperature Detectors or RTDs.

1.2 The materials of construction include copper, nickel-clad copper, copper-45 % nickel (constantan), or nickel conductors, an austenitic stainless steel or nickel-chromium alloy sheath, and either magnesia (MgO) or alumina (Al₂O₃) insulation.

1.3 The cable diameter is between 0.093 and 0.500 in. (2.33 and 12.70 mm) and contains between two and eight conductors, set in various design configurations and wire spacings.

1.4 The values of temperature in this specification are based on the International Temperature Scale of 1990 (ITS-90).

1.5 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.