ASTM E1350-18

Standard Guide for Testing Sheathed Thermocouples, Thermocouple Assemblies, and Connecting Wires Prior to, and After Installation or Service

SIGNIFICANCE AND USE
5.1 These test procedures confirm and document that the thermocouple assembly was not damaged prior to or during the installation process and that the extension wires are properly connected.  
5.2 The test procedures should be used when thermocouple assemblies are first installed in their working environment.  
5.3 In the event of subsequent thermocouple failure, these procedures will provide benchmark data to verify failure and may help to identify the cause of failure.  
5.4 The usefulness and purpose of the applicable tests will be found within each category.  
5.5 These tests are not meant to ensure that the thermocouple assembly will measure temperatures accurately. Such assurance is derived from proper thermocouple and instrumentation selection and proper placement in the location at which the temperature is to be measured. For further information, the reader is directed to MNL 12, Manual on the Use of the Thermocouples in Temperature Measurement2 which is an excellent reference document on metal sheathed thermocouple uses.
SCOPE
1.1 This guide covers methods for users to test metal sheathed thermocouple assemblies, including the extension wires just prior to and after installation or some period of service.  
1.2 The tests are intended to ensure that the thermocouple assemblies have not been damaged during storage or installation, to ensure that the extension wires have been attached to connectors and terminals with the correct polarity, and to provide benchmark data for later reference when testing to assess possible damage of the thermocouple assembly after operation. Some of these tests may not be appropriate for thermocouples that have been exposed to temperatures higher than the recommended limits for the particular type.  
1.3 The tests described herein include methods to measure the following characteristics of installed sheathed thermocouple assemblies and to provide benchmark data for determining if the thermocouple assembly has been subsequently damaged in operation:  
1.3.1 Loop Resistance:  
1.3.1.1 Thermoelements,
1.3.1.2 Combined extension wires and thermoelements.  
1.3.2 Insulation Resistance:  
1.3.2.1 Insulation, thermocouple assembly,
1.3.2.2 Insulation, thermocouple assembly and extension wires.  
1.3.3 Seebeck Voltage:  
1.3.3.1 Thermoelements,
1.3.3.2 Combined extension wires and thermocouple assembly.  
1.4 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.  
1.5 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.

General Information

• Status: Historical
• Publication Date: 30-Apr-2018
• ICS: 17.200.20 - Temperature-measuring instruments
• Technical Committee: E20 - Temperature Measurement
• Drafting Committee: E20.14 - Thermocouples - Testing

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: E1350 − 18 An American National Standard
Standard Guide for
Testing Sheathed Thermocouples, Thermocouple
Assemblies, and Connecting Wires Prior to, and After
1
Installation or Service
This standard is issued under the fixed designation E1350; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
INTRODUCTION
Thermocouples are widely used in industry and provide reliable service when used within their
specified temperature range. However, if thermocouples fail in service the consequences can range
from insignificant to life-threatening. Often, a costly loss of equipment, product, or operating time will
result. The user should weigh the potential consequences of thermocouple failure when considering
which tests should be performed either prior to, during, or after installation.
This standard is a guide for the field testing of thermocouples, thermocouple assemblies, and their
connecting wires to ensure that they were not damaged during storage, installation, or use rather than
being a guide for acceptance testing of thermocouples as delivered from the vendor. The test methods
range from basic tests to verify that the thermocouple was properly installed to tests necessary for
failure analysis. Thermocouple tests such as homogeneity, capacitance, and loop-current step-response
require elaborate equipment and sophisticated analysis and are not included in this guide.
Faulty installation practices and in-service operation beyond prescribed limits are frequently the
cause of failure in properly made sheathed thermocouples. Many of the most common types of these
application errors may be identified through use of the test methods described in this document. For
further information, the reader is directed to MNL 12, Manual on the Use of Thermocouples in
2
Temperature Measurement, which is an excellent reference document on metal sheathed thermo-
couples.
1. Scope thermocouples that have been exposed to temperatures higher
than the recommended limits for the particular type.
1.1 This guide covers methods for users to test metal
sheathed thermocouple assemblies, including the extension 1.3 The tests described herein include methods to measure
wires just prior to and after installation or some period of
the following characteristics of installed sheathed thermo-
service. couple assemblies and to provide benchmark data for deter-
mining if the thermocouple assembly has been subsequently
1.2 The tests are intended to ensure that the thermocouple
damaged in operation:
assemblies have not been damaged during storage or
1.3.1 Loop Resistance:
installation, to ensure that the extension wires have been
1.3.1.1 Thermoelements,
attached to connectors and terminals with the correct polarity,
1.3.1.2 Combined extension wires and thermoelements.
and to provide benchmark data for later reference when testing
to assess possible damage of the thermocouple assembly after 1.3.2 Insulation Resistance:
operation. Some of these tests may not be appropriate for
1.3.2.1 Insulation, thermocouple assembly,
1.3.2.2 Insulation, thermocouple assembly and extension
wires.
1
1.3.3 Seebeck Voltage:
This guide is under the jurisdiction of ASTM Committee E20 on Temperature
Measurement and is the direct responsibility of Subcommittee E20.14 on Thermo-
1.3.3.1 Thermoelements,
couples - Testing.
1.3.3.2 Combined extension wires and thermocouple assem-
Current edition approved May 1, 2018. Published May 2018. Originally
bly.
approved in 1991. Last previous edition approved in 2013 as E1350 – 13. DOI:
10.1520/E1350-18.
2 1.4 This standard does not purport to address all of the
Manual on the Use of Thermocouples in Temperature Measurement, MNL 12,
ASTM. Available from ASTM International, www.astm.org. safety concerns, if any, associated with its use. It is the
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
E1350 − 18
responsibility of the user of this standard to establish appro- electrically joined to form a thermocouple, or thermocouples,
priate safety, health, and environmental practices and deter- with its associated parts.
mine the applicability of regulatory limitations prior to use. 3.2.4.1 Discussion—An assembly may include associated
1.5 This international standard was developed in accor- parts such as a terminal block and a connection head. The metal
dance with internationally recognized principles on standard- protecting tube, or sheath, has a moisture seal at the reference
ization established in the D
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: E1350 − 13 E1350 − 18
Standard Guide for
Testing Sheathed Thermocouples,
ThermocouplesThermocouple Assemblies, and Connecting
1
Wires Prior to, and After Installation or Service
This standard is issued under the fixed designation E1350; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
INTRODUCTION
Thermocouples are widely used in industry and provide reliable service when used within their
specified temperature range. However, if thermocouples fail in service the consequences can range
from insignificant to life-threatening. Often, a costly loss of equipment, product, or operating time will
result. The user should weigh the potential consequences of thermocouple failure when considering
which tests should be performed either prior to, during, or after installation.
This standard is a guide for the field testing of thermocouples, thermocouple assemblies, and their
connecting wires to ensure that they were not damaged during storage, installation, or use rather than
being a guide for acceptance testing of thermocouples as delivered from the vendor. The test methods
range from basic tests to verify that the thermocouple was properly installed to tests necessary for
failure analysis. Thermocouple tests such as homogeneity, capacitance, and loop-current step-response
require elaborate equipment and sophisticated analysis and are not included in this guide.
Faulty installation practices and in-service operation beyond prescribed limits are frequently the
cause of failure in properly made sheathed thermocouples. Many of the most common types of these
application errors may be identified through use of the test methods described in this document. For
further information, the reader is directed to MNL 12, Manual on the Use of Thermocouples in
2
Temperature Measurement, which is an excellent reference document on metal sheathed thermo-
couples.
1. Scope
1.1 This guide covers methods for users to test metal sheathed thermocouple assemblies, including the extension wires just prior
to and after installation or some period of service.
1.2 The tests are intended to ensure that the thermocouple assemblies have not been damaged during storage or installation, to
ensure that the extension wires have been attached to connectors and terminals with the correct polarity, and to provide benchmark
data for later reference when testing to assess possible damage of the thermocouple assembly after operation. Some of these tests
may not be appropriate for thermocouples that have been exposed to temperatures higher than the recommended limits for the
particular type.
1.3 The tests described herein include methods to measure the following characteristics of installed sheathed thermocouple
assemblies and to provide benchmark data for determining if the thermocouple assembly has been subsequently damaged in
operation:
1.3.1 Loop Resistance:
1.3.1.1 Thermoelements,
1.3.1.2 Combined extension wires and thermoelements.
1.3.2 Insulation Resistance:
1.3.2.1 Insulation, thermocouple assembly,
1
This guide is under the jurisdiction of ASTM Committee E20 on Temperature Measurement and is the direct responsibility of Subcommittee E20.14 on Thermocouples
- Testing.
Current edition approved June 1, 2013May 1, 2018. Published July 2013May 2018. Originally approved in 1991. Last previous edition approved in 20072013 as
E1350 – 07.E1350 – 13. DOI: 10.1520/E1350-13.10.1520/E1350-18.
2
Manual on the Use of Thermocouples in Temperature Measurement, MNL 12, ASTM. Available from ASTM International, www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
E1350 − 18
1.3.2.2 Insulation, thermocouple assembly and extension wires.
1.3.3 Seebeck Voltage:
1.3.3.1 Thermoelements,
1.3.3.2 Combined extension wires and thermocouple assembly.
1.4 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 safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized prin
...