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ASTM B389-81(2020)

(Test Method)

Standard Test Method for Thermal Deflection Rate of Spiral and Helical Coils of Thermostat Metal

Standard Test Method for Thermal Deflection Rate of Spiral and Helical Coils of Thermostat Metal

SIGNIFICANCE AND USE
5.1 This test method simulates, to a practical degree, the operation of the thermostat metal coil.  
5.2 The thermal deflection properties of a coil may vary from lot-to-lot of thermostat metal material. This method is useful for determining the optimum thickness and length of the material for a given deflection specification.  
5.3 This method is useful as a quality test to determine acceptance or rejection of a lot of thermostat metal coils.
SCOPE
1.1 This test method covers the determination of the thermal deflection rate of spiral and helical coils of thermostat metal.  
1.2 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.  
1.3 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 become familiar with all hazards including those identified in the appropriate Safety Data Sheet (SDS) for this product/material as provided by the manufacturer, to establish appropriate safety, health, and environmental practices, and determine the applicability of regulatory limitations prior to use.  
1.4 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
Published
Publication Date
30-Sep-2020
ICS
29.120.20 - Connecting devices
Technical Committee
B02 - Nonferrous Metals and Alloys
Drafting Committee
B02.10 - Thermostat Metals and Electrical Resistance Heating Materials
Current Stage
Ref Project

Relations

Refers
ASTM E77-14 - Standard Test Method for Inspection and Verification of Thermometers
Effective Date
01-May-2014
Refers
ASTM E77-07 - Standard Test Method for Inspection and Verification of Thermometers
Effective Date
01-Dec-2007
Refers
ASTM E77-98(2003) - Standard Test Method for Inspection and Verification of Thermometers
Effective Date
01-Nov-2003

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ASTM B389-81(2020) - Standard Test Method for Thermal Deflection Rate of Spiral and Helical Coils of Thermostat MetalASTM B389-81(2020) - Standard Test Method for Thermal Deflection Rate of Spiral and Helical Coils of Thermostat Metal
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ASTM B389-81(2020) - Standard Test Method for Thermal Deflection Rate of Spiral and Helical Coils of Thermostat Metal
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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.
Designation: B389 −81 (Reapproved 2020)
Standard Test Method for
Thermal Deflection Rate of Spiral and Helical Coils of
Thermostat Metal
This standard is issued under the fixed designation B389; 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.
1. Scope differing expansivities of the components, tends to alter its
curvature when its temperature is changed.
1.1 Thistestmethodcoversthedeterminationofthethermal
3.2 thermal deflection rate, n—the ratio of angular rotation
deflection rate of spiral and helical coils of thermostat metal.
to temperature change. It is a measure of the coil’s thermal
1.2 The values stated in inch-pound units are to be regarded
activity. It may have the units of angular degrees per degree
as standard. The values given in parentheses are mathematical
Fahrenheit, or Celsius, and is expressed by the equation
conversions to SI units that are provided for information only
D=(A −A )/(T −T ) where A and A are angular positions
2 1 2 1 2 1
and are not considered standard.
at temperature T and T respectively.
2 1
1.3 This standard does not purport to address all of the
3.3 spiral coil, n—a part made by winding strip on itself.
safety concerns, if any, associated with its use. It is the
Fig. 1 and Fig. 2 show typical spiral coils, which can be wound
responsibility of the user of this standard to become familiar
with the low-expansive side inside or outside, mounted on the
with all hazards including those identified in the appropriate
specimen holder.
Safety Data Sheet (SDS) for this product/material as provided
3.4 helical coil, n—a part made by winding strip in a form
by the manufacturer, to establish appropriate safety, health,
wherein the plane of the width of the strip is parallel to the
and environmental practices, and determine the applicability
axial length. Fig. 3 shows a typical helical coil, which can be
of regulatory limitations prior to use.
wound with the low-expansive side inside or outside, and
1.4 This international standard was developed in accor-
right-hand or left-hand, mounted on the specimen holder.
dance with internationally recognized principles on standard-
ization established in the Decision on Principles for the
4. Summary of Test Method
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
4.1 The test for thermal deflection rate of spiral and helical
Barriers to Trade (TBT) Committee.
coils consists of measuring the angular rotation that a coil
undergoes in response to a known temperature change.
2. Referenced Documents
2.1 ASTM Standards: 5. Significance and Use
E77 Test Method for Inspection and Verification of Ther-
5.1 This test method simulates, to a practical degree, the
mometers
operation of the thermostat metal coil.
5.2 The thermal deflection properties of a coil may vary
3. Terminology
from lot-to-lot of thermostat metal material. This method is
3.1 thermostat metal, n—a composite material, usually in
useful for determining the optimum thickness and length of the
the form of sheet or strip, comprising two or more materials of
material for a given deflection specification.
any appropriate nature, metallic or otherwise, that, by virtue of
5.3 This method is useful as a quality test to determine
acceptance or rejection of a lot of thermostat metal coils.
This test method is under the jurisdiction of ASTM Committee B02 on
6. Apparatus
Nonferrous Metals and Alloys and is the direct responsibility of Subcommittee
B02.10 on Thermostat Metals and Electrical Resistance Heating Materials.
6.1 Temperature Bath—A stirred liquid bath or uniformly
Current edition approved Oct. 1, 2020. Published October 2020. Originally
heated enclosure in which the specimen and mounting fixture
approved in 1962. Last previous edition approved in 2016 as B389 – 81 (2016).
DOI: 10.1520/B0389-81R20.
can be placed shall be used. An adjustable heating source is
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
desirable for maintaining the specimen at the desired tempera-
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
tures with a variation in temperature throughout the specimen
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. not to exceed 0.5°F (0.3°C).
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
B389 − 81 (2020)
and the top end allowed to rotate freely with a temperature
change. Preferably the end of the coil with the center tab shall
be considered the bottom and secured by clamping or press-
fitting the tab into a slotted arbor similar to that described in
6.4.1 for spiral coils.The depth of the slot shall be such that the
full height of the tab shall be held. If the coils do not have a
center tab, the arbor shall contain provisions for attaching the
coil with screws, rivets, or by welding. A transmission pointer
can be affixed to the top end. The center line of the coil, the
transmission pointer, and the protractor shall coincide.
6.4.3 Deviations from these procedures of holding may be
necessary when simulating the mounting used in the device for
which the coil was designed, or in cases where coils are press
fitted on arbors. In these cases, the details of mounting should
be mutually agreed upon between the manufacturer and the
purchaser.
6.5 Transmission Pointer:
6.5.1 Spiral Coils—To the outer end of the spiral coil shall
be attached a pointer that will transmit the rotation of the coil
so that it can be read on the protractor. The pointer shall be of
lightweight construction and attached to the coil by suitable
means so that the movement of these portions of the coil that
do not normally contribute to the movement of the coil with a
temperature change shall not influence the rotation of the
pointer. The pointer, when using the fixture shown in Fig. 1,
shall be so positioned that its tip shall ride slightly above the
divisions of the protractor, but shall not touch the protractor at
any time during the test. The pointer, when using the fixture
shown in Fig. 2, shall be of sufficient length so that the top may
FIG. 1 Spiral Coil
protrude from the bath when the coil is submerged.The pointer
f
...

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SCOPE
1.1 This test method covers all residential pressure connection systems. Detailed examples of application to specific types of connection systems, set-screw neutral bus connectors, and twist-on wire-splicing connectors are provided in Appendix X1 and Appendix X2.  
1.2 The purpose of this test method is to evaluate the performance of residential electrical pressure connection systems under conditions of cyclic temperature change (within rating) and high humidity.  
1.3 The limitations of the test method are as follows:  
1.3.1 This test method shall not be considered to confirm a specific lifetime in application environments.  
1.3.2 The applicability of this test method is limited to pressure connection systems rated at or below 600 V d-c or a-c RMS.  
1.3.3 This test method is limited to temperature and water vapor exposure in addition to electrical current as required to measure connection resistance.  
1.3.4 This test method does not evaluate degradation which may occur in residential applications due to exposure of the electrical connection system to additional environmental constituents such as (but not limited to) the following examples:
1.3.4.1 Household chemicals (liquid or gaseous) such as ammonia, bleach, or other cleaning agents.
1.3.4.2 Chemicals as may occur due to normal hobby or professional activities such as photography, painting, sculpture, or similar activities.
1.3.4.3 Environments encountered during construction or remodeling such as direct exposure to rain, uncured wet concrete, welding or soldering fluxes and other agents.  
1.3.5 This test method is limited to evaluation of pressure connection systems.  
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 become familiar with all hazards including those identified in the appropriate Safety Data Sheet (SDS) for this product...

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ASTM
ASTM B845-97(2024)(Guide)
Standard Guide for Mixed Flowing Gas (MFG) Tests for Electrical Contacts

SIGNIFICANCE AND USE
4.1 Preservation of a conducting surface on electrical contact is vital to the continued functioning of such contacts. Contamination of the surface with insulating layers formed by corrosion processes is one potential hazard. Laboratory testing of contacts in MFG tests is used to assess the effectiveness of design features and materials.  
4.2 MFG tests are used in development studies of processes and materials for contacts. For example, coupon specimens may be exposed to MFG tests to evaluate new contact materials, layers of new coating materials on a supporting substrate, reduced coating thicknesses, or protective surface treatments.  
4.3 MFG tests are also employed to test the durability of a finished product with respect to atmospheric corrosion. For example, finished connectors may be exposed to a MFG test and their performances compared against each other or against a set of fixed requirements. Relays or switch contacts may be exposed in the operated and non-operated conditions to compare performance.  
4.4 MFG tests are useful for determining the effectiveness of connector housings and shrouds as barriers to ingress of atmospheric corrodants to the contact surfaces. These tests can also be used to assess the screening of the metal-to-metal contact areas of mated connectors.  
4.5 MFG tests are employed as qualification tests to determine connector failure rates in application environments for which correlation between test and application has previously been established.  
4.6 This guide provides test conditions which are to be applied in conjunction with Practice B827 which defines the required test operation and certification procedures, tolerances, and reporting requirements. Where the test specifier requires certifications or tolerances different than those provided in Practice B827, the required certifications or tolerances shall be part of the test specification. Differences from the specifications in Practice B827 shall be reported in the test re...
SCOPE
1.1 The techniques described in this guide pertain to mixed flowing gas (MFG) tests containing species that are applied to evaluate devices containing electrical contacts such as slip rings, separable connectors, electromechanical relays or switch contacts. These techniques may be relevant to other devices, but it is the responsibility of the user to determine suitability prior to testing.  
1.2 The MFG tests described in this guide are designed to accelerate corrosive degradation processes. These accelerations are designed such that the degradation occurs in a much shorter time period than that expected for such processes in the intended application environment of the device being tested. Application environments can vary continuously from benign to aggressively corrosive. Connectors and contacts within closed electronic cabinets may be affected by an environment of different severity than the environment on the outside of such cabinets. In general, indoor environments are different than outdoor environments. The MFG tests described herein, being discrete embodiments of specific corrosive conditions, cannot be representative of all possible application environments. It is the responsibility of the test specifier to assure the pertinence of a given test condition to the specifier's application condition.  
1.3 The MFG tests described herein are not designed to duplicate the actual intended application environment of the device under test. An extended bibliography that provides information which is useful to test specifiers to assist them in selecting appropriate test methods is included in this guide. The bibliography covers the scope from application condition characterization, single and multiple gas effects, and material and product effects to key application and test variables as well as discussions of atmospheric corrosion processes.  
1.4 The values stated in SI units are to be regarded as standard. No other uni...

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