ASTM E601-07e1
Historical Standard: ASTM E601-07e1 Standard Test Method for Measuring Electromotive Force (emf) Stability of Base-Metal Thermoelement Materials with Time in Air
SUPERSEDED (see Active link, below)
ASTM E601
1. Scope
1.1 This test method measures emf stability of base-metal thermoelement materials in air referenced to platinum at specified constant elevated temperatures using dual, simultaneous, emf indicators, or using a single emf indicator, with the test and reference emf measured alternately. This test is conducted over a period of weeks.
1.2 A calibrated platinum-rhodium/platinum thermocouple is used as a reference standard to establish the test temperature.
1.3 The useful life of a thermocouple depends on the stability of the emf generated at given temperatures for a required time interval. This method provides a quantitative measure of the stability of individual thermoelements. By combining the results of the positive (P) and negative (N) thermoelements, the stability of a thermocouple comprised of both P and N thermoelements may be obtained. The emf of an individual thermoelement is measured against platinum, which may be the platinum leg of the platinum-rhodium/platinum reference thermocouple, or an additional platinum reference.
Note 1Some thermoelements may show insignificant emf drift while undergoing relatively rapid oxidation. In these cases, failure of the thermoelement may be indicated only by a large rise in the electrical resistance of the thermocouple, as measured between the reference junctions.
Note 2See ASTM MNL 12 for recommended upper temperature limits in air.
Note 3This test method is only applicable for initially new thermoelements. Base-metal thermoelements exposed to temperatures above 200 C become thermoelectrically inhomogeneous, and stability testing of inhomogeneous thermoelements will give ambiguous results.
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 and health practices and determine the applicability of regulatory limitations prior to use.
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
ASTM Standards
E220 Test Method for Calibration of Thermocouples By Comparison Techniques
E230 Specification and Temperature-Electromotive Force (EMF) Tables for Standardized Thermocouples
E344 Terminology Relating to Thermometry and Hydrometry
E563 Practice for Preparation and Use of an Ice-Point Bath as a Reference Temperature
E1159 Specification for Thermocouple Materials, Platinum-Rhodium Alloys, and Platinum
Keywords
Comparison techniques; Single thermoelement materials; Thermocouples ;
ICS Code
ICS Number Code 17.200.20 (Temperature-measuring instruments)
DOI: 10.1520/E0601-07E01
ASTM International is a member of CrossRef.