1、Designation: D1830 99 (Reapproved 2012)D1830 17Standard Test Method forThermal Endurance of Flexible Sheet Materials Used forElectrical Insulation by the Curved Electrode Method1This standard is issued under the fixed designation D1830; the number immediately following the designation indicates the
2、year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S.
3、Department of Defense.1. Scope1.1 This test method provides a procedure for evaluating thermal endurance of flexible sheet materials by determining dielectricbreakdown voltage at room temperature after aging in air at selected elevated temperatures. Thermal endurance is expressed interms of a temper
4、ature index.1.2 This test method is applicable to such solid electrical insulating materials as coated fabrics, dielectric films, compositelaminates, and other materials where retention of flexibility after heat aging is of major importance (see Note 4).1.3 This test method is not intended for the e
5、valuation of rigid laminate materials nor for the determination of thermal enduranceof those materials which are not expected or required to retain flexibility in actual service.1.4 The values stated in acceptable metric units are to be regarded as the standard. The values in parentheses are for inf
6、ormationonly.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety safety, health, and healthenvironmental practices and determine theapplicability of regulatory
7、limitations prior to use. For a specific hazard statement, see 10.1.1.6 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommenda
8、tions issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D149 Test Method for Dielectric Breakdown Voltage and Dielectric Strength of Solid Electrical Insulating Materials atCommercial Power FrequenciesD374 Test Methods for Th
9、ickness of Solid Electrical Insulation (Metric) D0374_D0374MD5423 Specification for Forced-Convection Laboratory Ovens for Evaluation of Electrical Insulation2.2 Institute of Electrical and Electronics Engineers Publications:3IEEE No. 1 General Principles for Temperature Limits in the Rating of Elec
10、trical EquipmentIEEE No. 101A Guide for the Statistical Analysis of Thermal Life Test Data (including Appendix A)2.3 IEC Publications:IEC 216 Guide for the Determination of Thermal Endurance Properties of Electrical Insulating Materials (Parts 1 and 2)43. Terminology3.1 Definitions:1 This test metho
11、d is under the jurisdiction of ASTM Committee D09 on Electrical and Electronic Insulating Materials and is the direct responsibility of SubcommitteeD09.01 on Electrical Insulating ProductsCurrent edition approved Jan. 1, 2012Nov. 1, 2017. Published January 2012December 2017. Originally approved in 1
12、961. Last previous edition approved in 20052012as D1830 99 (2005).(2012). DOI: 10.1520/D1830-99R12.10.1520/D1830-17.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to t
13、he standards Document Summary page on the ASTM website.3 Available from Institute of Electrical and Electronics Engineers, Inc. (IEEE), 445 Hoes Ln., P.O. Box 1331, Piscataway, NJ 08854-1331.4 Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036.
14、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. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior edi
15、tions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.1.1 temperature index, na number which permits
16、 comparison of the temperature/time characteristics of an electricalinsulating material, or a simple combination of materials, based on the temperature in degrees Celsius which is obtained byextrapolating the Arrhenius plot of life versus temperature to a specified time, usually 20 000 h.3.1.2 therm
17、al life, nthe time necessary for a specific property of a material, or simple combination of materials, to degradeto a defined end point when aged at a specific temperature.3.1.3 thermal life curve, na graphical representation of thermal life at a specified aging temperature in which the value of ap
18、roperty of a material, or a simple combination of materials, is measured at room temperature and the values plotted as a functionof time.3.2 Definitions of Terms Specific to This Standard:3.2.1 thermal endurance grapha straight-line plot of the logarithm of thermal life in hours versus the reciproca
19、l of the absoluteaging temperature in kelvins (also known as the Arrhenius plot).4. Summary of Test Method4.1 Specimens are aged in air at a minimum of three temperatures above the expected use temperature of the material. Dielectricbreakdown voltage tests in air at room temperature are periodically
20、 made to determine the time of aging at each test temperaturerequired to reduce the breakdown voltage to a value of 12 kV/mm (300 V/mil) of original thickness. These thermal life values areused to construct a thermal endurance graph by means of which temperature indices may be are estimated correspo
21、nding to athermal life as specified in the material specification or as agreed upon between the user and the supplier.NOTE 1This test method is not applicable to materials having an initial dielectric breakdown voltage of less than 12 kV/mm (300 V/mil) of originalthickness unless lower endpoint valu
22、es are agreed upon or indicated in the applicable material specifications.5. Significance and Use5.1 Amajor factor affecting the life of insulating materials is thermal degradation. Other factors, such as moisture and vibration,may are able to cause failures after the material has been weakened by t
23、hermal degradation.5.2 Electrical insulation is effective in electrical equipment only as long as it retains its physical and electrical integrity. Thermaldegradation may is able to be characterized by weight change, porosity, crazing, and generally a reduction in flexibility, and isusually accompan
24、ied by an ultimate reduction in dielectric breakdown voltage.6. Apparatus6.1 Electrode Test FixtureThe fixture shall be in accordance with the dimensions shown in Fig. 1 and Fig. 2. Electrodes shallbe of polished brass, with the upper electrode having a mass of 1.8 6 0.05 kg (4.0 6 0.1 lb).6.2 Diele
25、ctric Breakdown Test SetThe set shall meet the requirements of Test Method D149.Insulation Thickness Dimension R Dimension H Dimension Dmm in. mm in. mm in. mm in.0.18 0.007 4.55 0.179 8.15 0.321 8.71 0.3440.25 0.010 6.48 0.255 6.22 0.245 2.45 0.4900.30 0.012 7.77 0.306 4.93 0.194 4.94 0.588Toleranc
26、e for R and D = 60.03 mm (0.001 in.)Tolerance for H = 60.05 mm (0.002 in.)FIG. 1 Curved Electrode DetailsD1830 1726.3 OvensOvens shall meet the requirements of Specification D5423 Type II.6.4 MicrometerThe micrometer shall be of the dead-weight type specified in Methods C or D of Test Methods D374,
27、havinga pressor foot 6.35 6 0.03 mm (0.25 6 0.001 in.) in diameter and an anvil of at least 50 mm (2 in.) in diameter and shall exerta pressure of 0.17 6 0.01 MPa (25 6 2 psi) on the anvil.7. Test Specimens7.1 Test specimens shall be at least 250 mm (9.84 in.) long by 130 mm (5.12 in.) wide, with th
28、e machine direction parallel tothe longer direction.7.2 A set of test specimens consists of five specimens. Prepare one set for initial (unaged) tests and five sets for each agingtemperature chosen (15 sets for three temperatures).7.3 In the case of coated glass fabrics, make tests on 0.18-mm (0.007
29、-in.) material having 0.08-mm (0.003-in.) or 0.10-mm(0.004-in.) base cloth, or on 0.25-mm (0.010-in.) or 0.30-mm (0.012-in.) material having respectively 0.10-mm (0.004-in.) or0.13-mm (0.005-in.) base cloth.NOTE 2Experience has shown that unrealistically extended life data usually result when the ba
30、se fabrics of glass exceed the thicknesses specifiedpreviously for the corresponding coated thicknesses. Similar data are not available for other types of coated fabrics, and the user of this test method isurged to investigate this relationship to determine similar limitations, if any.8. Test Specim
31、en Selection8.1 Select test specimens from the sample in such manner that they are randomly distributed among the sets.NOTE 3This can be is conveniently accomplished by the following procedure, as an example: In the case of full-width material in rolls or sheets,select an area sufficient to provide
32、a panel about 1 m (3.28 ft) wide by 3 m (9.84 ft) long. Using a suitable marking device, construct a grid of 7 linesspaced 130 mm (5.12 in.) across and 12 lines spaced 250 mm (9.84 in.) (9.84 in.) down, with an edge margin of about 50 mm (1.97 in.) on each side.This will provide 84 boxes, each delin
33、eating a test specimen. Number the boxes consecutively across and down the grid. Using a set of random numbers,obtain a selection of 16 sets of test specimens. In the case of slit material in rolls, number specimens as removed from the roll and obtain a randomselection of test sets as in 8.1.FIG. 2
34、Curved Electrode and HolderD1830 1739. Selection of Test Temperatures9.1 Expose the material at not less than three temperatures. Any temperature that gives a thermal life of less than 100 h isconsidered too high to be used in this evaluation. Choose the lowest temperature such that (1) a thermal li
35、fe of at least 5000 h5000 h is obtained and (2) it shall not be more than 25C higher than the estimated temperature index. Exposure temperatures shalldiffer by at least 20C.9.2 Select exposure temperatures in accordance with those shown in Table 1 as indicated by the anticipated temperature indexof
36、the material under test. It is recommended that exploratory tests be first made at the highest temperature to obtain dataestablishing the validity of the 100 h minimum life requirement (see 9.1), and that this be used as a guide for the selection of thelower test temperatures.10. Procedure10.1 WARNI
37、NGLethal voltages are a potential hazard during the performance of this test. It is essential that the testapparatus, and all associated equipment electrically connected to it, be properly designed and installed for safe operation. Solidlyground all electrically conductive parts which it is possible
38、 for a person to contact during the test. Provide means for use at thecompletion of any test to ground any parts which were at high voltage during the test or have the potential for acquiring an inducedcharge during the test or retaining a charge even after disconnection of the voltage source. Thoro
39、ughly instruct all operators asto the correct procedures for performing tests safely. When making high voltage tests, particularly in compressed gas or in oil, itis possible for the energy released at breakdown to be suffcient to result in fire, explosion, or rupture of the test chamber. Designtest
40、equipment, test chambers and test specimens so as to minimize the possibility of such occurrences and to eliminate thepossibility of personal injury. If the potential for fire exists, have fire suppression equipment available.10.2 Thickness MeasurementMake 16 thickness measurements before aging, usi
41、ng one specimen from each set prepared.Determine the thickness in accordance with Methods C or D of Test Methods D374, holding the pressor foot on the specimen for2 s before taking a reading. Compute the average thickness in millimetres or inches.10.3 Dielectric Breakdown Voltage (Unaged)Condition o
42、ne set of specimens for at least 48 h at 23 6 1C and 50 6 2 %relative humidity. Determine the dielectric breakdown voltage in air at room temperature by the short-time test of Test MethodD149, using a rate of voltage rise of 500 V/s. Make one measurement on each specimen and compute the average diel
43、ectricbreakdown voltage for the set.10.4 Aging of SpecimensTag five sets of specimens by any reliably permanent means and expose the sets in the oven at thehighest temperature. Position the sets so that free movement of air exists across both sides of the specimens.NOTE 4For materials that tend to w
44、arp appreciably in heat, specimens may be are weighted (in cases where the oven is designed for vertical airmovement) or mounted on restraining frames. In either case, the method of restraint shall allow for normal shrinkage during aging and not induceelongation or stress in the specimens. In cases
45、where the specimens become warped, the operator shall endeavor to select portions of the specimens fordielectric breakdown voltage tests so that the electrodes do not prematurely damage the specimens by distortion.10.5 Testing of Specimens:10.5.1 Remove one set of specimens after completion of the c
46、ycle shown in Table 1. Condition the set for 4 h at 23 6 1C and50 6 2 % relative humidity.10.5.2 Immediately make one dielectric breakdown voltage measurement in air at room temperature on each specimen of theset and compute the average breakdown voltage. Return the set to the aging oven.10.5.3 Remo
47、ve the same set at the end of the next aging period, condition as prescribed in 10.5.1 and again measure thebreakdown voltage on each specimen. Compute the average breakdown voltage for the set, this time discarding the set.10.5.4 Using this procedure, test the remaining sets until all sets have bee
48、n tested twice, giving a total of ten average breakdownvoltage measurements.TABLE 1 Suggested Exposure Temperatures and Cycle DurationsACycleDuration,daysTemperatures Corresponding to the Estimated Temperature Index Range, CClass 105B Class 130 Class 155 Class 180 Class 200 100109 110119 120129 1301
49、39 140149 150159 160169 170179 180189 190199 200209 210219 220229 2302391 170 180 190 200 210 220 230 240 250 260 270 280 290 3002 160 170 180 190 200 210 220 230 240 250 260 270 280 2904 150 160 170 180 190 200 210 220 230 240 250 260 270 2807 140 150 160 170 180 190 200 210 220 230 240 250 260 27014 130 140 150 160 170 180 190 200 210 220 230 240 250 26028 120 130 140 150 160 170 180 190 200 210 220 230 240 25049 110 120 130 140 150 160 170 180 190 200 210 220 230 240A Taken from IEC Publication 216-1.B Classes shown correspond to those des
