ASTM A927/A927M-11
(Test Method)Standard Test Method for Alternating-Current Magnetic Properties of Toroidal Core Specimens Using the Voltmeter-Ammeter-Wattmeter Method
Standard Test Method for Alternating-Current Magnetic Properties of Toroidal Core Specimens Using the Voltmeter-Ammeter-Wattmeter Method
SIGNIFICANCE AND USE
This test method is a derivative of Test Method A697/A697M specifically designed for testing of toroidal cores which are not covered in Test Method A697/A697M and for testing at magnetic flux densities above the knee of the magnetization curve.
Specimen size typically ranges from 1 to 1.25 in. [25.4 to 31.8 mm] in inside diameter to 1.5 in. [38.1 mm] in outside diameter with weights ranging from 30 to 60 g. Provided the test equipment is suitably chosen, there is no obvious limit to the overall size of core that can be tested. If basic material properties are desired, then the requirements of 5.1 must be observed.
The reproducibility and repeatability of this test method are such that this test method is suitable for design, specification acceptance, service evaluation, and research and development.
When testing under sinusoidal flux conditions at magnetic flux densities approaching saturation, highly peaked magnetizing waveforms will be present, and the test instruments used must have crest factor capabilities of at least 3; otherwise erroneous results will be obtained.
SCOPE
1.1 This test method covers the determination of several ac magnetic properties of either laminated ring or toroidal tape wound cores made from flat rolled product.
1.2 This test method covers test equipment and procedures for determination of specific core loss, specific exciting power, and peak permeability for power and audio frequencies (50 to 20 000 Hz) under sinusoidal flux conditions.
1.3 This test method, because of the use of a feedback-controlled power amplifier, is well suited for determination of ac magnetic properties at magnetic flux densities above the knee of the magnetization curve and is particularly useful for testing of high-saturation iron-cobalt alloys (for example, alloys listed in Specification A801), although use of this test method is not restricted to a particular type of material.
1.4 This test method shall be used in conjunction with Practice A34/A34M and Terminology A340.
1.5 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the 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 and health practices and determine the applicability of regulatory limitations prior to use.
General Information
Relations
Buy Standard
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: A927/A927M − 11
Standard Test Method for
Alternating-Current Magnetic Properties of Toroidal Core
Specimens Using the Voltmeter-Ammeter-Wattmeter
1
Method
This standard is issued under the fixed designationA927/A927M; the number immediately following the designation indicates the year
of original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.
A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 2. Referenced Documents
2
2.1 ASTM Standards:
1.1 This test method covers the determination of several ac
A34/A34MPractice for Sampling and Procurement Testing
magnetic properties of either laminated ring or toroidal tape
of Magnetic Materials
wound cores made from flat rolled product.
A340Terminology of Symbols and Definitions Relating to
1.2 This test method covers test equipment and procedures
Magnetic Testing
fordeterminationofspecificcoreloss,specificexcitingpower,
A697/A697MTestMethodforAlternatingCurrentMagnetic
and peak permeability for power and audio frequencies (50 to
Properties of Laminated Core Specimen UsingVoltmeter-
20000 Hz) under sinusoidal flux conditions.
Ammeter-Wattmeter Methods
A801Specification for Wrought Iron-Cobalt High Magnetic
1.3 This test method, because of the use of a feedback-
Saturation Alloys (UNS R30005 and K92650)
controlled power amplifier, is well suited for determination of
ac magnetic properties at magnetic flux densities above the
3. Significance and Use
knee of the magnetization curve and is particularly useful for
3.1 This test method is a derivative of Test Method A697/
testing of high-saturation iron-cobalt alloys (for example,
A697M specifically designed for testing of toroidal cores
alloys listed in Specification A801), although use of this test
which are not covered in Test Method A697/A697M and for
method is not restricted to a particular type of material.
testing at magnetic flux densities above the knee of the
1.4 This test method shall be used in conjunction with
magnetization curve.
Practice A34/A34M and Terminology A340.
3.2 Specimen size typically ranges from 1 to 1.25 in. [25.4
to 31.8 mm] in inside diameter to 1.5 in. [38.1 mm] in outside
1.5 The values stated in either SI units or inch-pound units
diameter with weights ranging from 30 to 60 g. Provided the
are to be regarded separately as standard. The values stated in
test equipment is suitably chosen, there is no obvious limit to
each system may not be exact equivalents; therefore, each
the overall size of core that can be tested. If basic material
system shall be used independently of the other. Combining
properties are desired, then the requirements of 5.1 must be
values from the two systems may result in non-conformance
observed.
with the standard.
3.3 The reproducibility and repeatability of this test method
1.6 This standard does not purport to address all of the
are such that this test method is suitable for design, specifica-
safety concerns, if any, associated with its use. It is the
tion acceptance, service evaluation, and research and develop-
responsibility of the user of this standard to establish appro-
ment.
priate safety and health practices and determine the applica-
3.4 When testing under sinusoidal flux conditions at mag-
bility of regulatory limitations prior to use.
netic flux densities approaching saturation, highly peaked
magnetizing waveforms will be present, and the test instru-
ments used must have crest factor capabilities of at least 3;
otherwise erroneous results will be obtained.
1
This test method is under the jurisdiction ofASTM Committee A06 and is the
2
direct responsibility of Subcommittee A06.01 on Test Methods. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved Aug. 1, 2011. Published August 2011. Originally contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
approved in 1994. Last previous edition approved in 2004 as A927/A927M–04. Standards volume information, refer to the standard’s Document Summary page on
DOI: 10.1520/A0927_A0927M-11. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1
---------------------- Page: 1 ----------------------
A927/A927M − 11
4. Apparatus current and rms voltage to an accuracy of 60.5% or better;
otherwise, separate instruments meeting this accuracy require-
4.1 The apparatus for testing under this test method shall
ment must be used.
consist of as many of the components, described below and
schematically illustrated in Fig. 1, as required to perform the 4.5 Flux Voltmeter—The flux voltmeter must be a true
measurements. average responding, high-impedance voltmeter calibrated to
read =2 π/4 times the
...
This document is not anASTM standard and is intended only to provide the user of anASTM 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:A927/A927M–04 Designation:A927/A927M–11
Standard Test Method for
Alternating-Current Magnetic Properties of Toroidal Core
Specimens Using the Voltmeter-Ammeter-Wattmeter
1
Method
This standard is issued under the fixed designationA927/A927M; the number immediately following the designation indicates the year
of original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.
A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This test method covers the determination of several ac magnetic properties of either laminated ring or toroidal tape wound
cores made from flat rolled product.
1.2 This test method covers test equipment and procedures for determination of specific core loss, specific exciting power, and
peak permeability for power and audio frequencies (50 to 20000 Hz) under sinusoidal flux conditions.
1.3 This test method, because of the use of a feedback-controlled power amplifier, is well suited for determination of ac
magnetic properties at magnetic flux densities above the knee of the magnetization curve and is particularly useful for testing of
high-saturation iron-cobalt alloys (for example, alloys listed in Specification A801), although use of this test method is not
restricted to a particular type of material.
1.4 This test method shall be used in conjunction with Practice A34/A34M and Terminology A340.
1.5Thevaluesandequationsstatedincustomary(cgs-emuandinch-pound)orSIunitsaretoberegardedseparatelyasstandard.
Within this standard, SI units are shown in brackets except for the sections concerning calculations where there are separate
sectionsfortherespectiveunitsystems.Thevaluesstatedineachsystemmaynotbeexactequivalents;therefore,eachsystemshall
be used independently of the other. Combining values from the two systems may result in nonconformance with this standard.
1.5 The values stated in either SI units or inch-pound units are to be regarded separately as standard.The values stated in each
system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the
two systems may result in non-conformance with the 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 and health practices and determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
2
2.1 ASTM Standards:
A34/A34M Practice for Sampling and Procurement Testing of Magnetic Materials
A340 Terminology of Symbols and Definitions Relating to Magnetic Testing
A697/A697M Test Method for Alternating Current Magnetic Properties of Laminated Core Specimen Using Voltmeter-
Ammeter-Wattmeter Methods
A801 Specification for Wrought Iron-Cobalt High Magnetic Saturation Alloys (UNS R30005 and K92650)
3. Significance and Use
3.1 This test method is a derivative of Test MethodA697/A697M specifically designed for testing of toroidal cores which are
not covered in Test Method A697/A697M and for testing at magnetic flux densities above the knee of the magnetization curve.
3.2 Specimen size typically ranges from 1 to 1.25 in. [25.4 to 31.8 mm] in inside diameter to 1.5 in. [38.1 mm] in outside
diameter with weights ranging from 30 to 60 g. Provided the test equipment is suitably chosen, there is no obvious limit to the
overall size of core that can be tested. If basic material properties are desired, then the requirements of 5.1 must be observed.
3.3 The reproducibility and repeatability of this test method are such that this test method is suitable for design, specification
acceptance, service evaluation, and research and development.
3.4 Whentestingundersinusoidalfluxconditionsatmagneticfluxdensitiesapproachingsaturation,highlypeakedmagnetizing
1
This test method is under the jurisdiction ofASTM CommitteeA06 on Magnetic Properties and is the direct responsibility of SubcommitteeA06.01 on Test Methods.
Current edition approved Oct.Aug. 1, 2004.2011. Published October 2004.August 2011. Originally approved in 1994. Last previous edition approved in 19992004 as
A927/A927M–99.A927/A927M–04. DOI: 10.1520/A0927_A0927M-0411.
2
ForreferencedASTMstandards,visittheASTMwebsite,www.astm.org,orcontactASTMCustomerServiceatservice@astm.org.For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM Inte
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.