Buy ASTM Da() Standard Test Method for Dielectric Breakdown Voltage and Dielectric Strength of Solid Electrical Insulating Materials at. Dielectric Strength ASTM D, IEC Scope: Dielectric Strength is a measure of the electrical strength of a material as an insulator. Dielectric strength is. ASTM DA – Designation: D – 97a (Reapproved ) An American National Standard Standa.
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Breakdown values obtained in insulating liquid may not be comparable with those obtained in air. Motor-driven controls are preferable for making short-time see D — 97a 6. 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.
Dielectric Strength ASTM D149, IEC 60243
Standards which refer to this method should determine for the material with which that standard is concerned the applicability of this precision statement to that particular material. Solidly ground all electrically conductive parts that any person might come into contact with during the test.
If the time to breakdown cannot be adhered to, the time shall be made a part of the report. Use appropriate means, such as exhaust vents, to reduce ozone concentrations to acceptable levels in working areas. If breakdown occurs prior to the end of the holding period at any step, the dielectric withstand voltage, Vws, for the specimen is taken as the voltage at the last completed step. Discharges may occur in any internal voids or bubbles that are present or may develop.
Hence, its importance will depend to a large extent upon the nature of the material being tested. C The electrodes surfaces shall be polished and free from irregularities resulting from previous testing. Standards which refer to this method need to determine for the material with which that standard is concerned the applicability of this precision statement to that particular material.
Results may be affected also by the material from which the electrodes are constructed, since the thermal and discharge mechanism may be inuenced by the thermal conductivity and the work function, respectively, of the electrode material. Do not allow the peak qstm to exceed 1. Except in cases where the effect of exposure on dielectric strength is being investigated, it is customary to control or limit the relative humidity effects by standard conditioning procedures.
With the addition of instructions modifying Section 12, this test method is also suitable for use for proof testing. Validating the specifications, value and safety of your raw materials, products and assets. The breakdown mechanisms astmm operate in combination rather than singly. Weak spots within the volume under stress sometimes determine the test results.
Assurance Testing Inspection Certification. Ordinarily the rate is selected to approximate the average rate for d14-97a step-by-step test. Last previous edition approved in as D — 97a.
This type of failure, usually associated with slowrise tests at elevated temperatures, may in some cases be reversible, that is, recovery of the dielectric strength may occur if the specimen is allowed to cool to its original test temperature before reapplying voltage. Techniques that may be used to prevent ashover, or to reduce partial discharge corona include: Method A is the most commonly-used test for quality-control tests.
Some of these effects can be incorporated in laboratory tests, and a better estimate of the material will result, but the? The nature of the insulating liquid and the degree of previous use are factors 4 in? First, the condition of a material as installed in apparatus is much different from its condition in this test, particularly with regard to the con?
Metal baths must be grounded. In this case, the times to failures shall be made a part of the report.
Active view current version of standard. Within the limits specied in this method the inuence of wave form is not signicant.
Generally speaking, the effect of the electrode material is difficult to establish because of the scatter of experimental data. ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this standard.
Dielectric Strength ASTM D, IEC
Test results are also affected by the electrode geometry. Reference shall be made to the standard governing the material to be tested to determine which, if either, material is preferable. Test results are also affected by the electrode geometry. Do not use another document, including those listed in f149-97a appendix, as a model for reference to this test method unless there is conformity with 5.