ASTM D specifies that for insulating fluids to qualify ASTM D – Standard Test Method for Dielectric Breakdown Voltage of Insulating Liquids Using. Page 1. Page 2. Page 3. Page 4. ASTM D DIELECTRIC BREAKDOWN VOLTAGE OF LIQUIDS. This test method describes two procedures, A and B, for determining the electrical breakdown.
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Originally approved in ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this standard. This disk is acceptable, however, consideration should be given to machining the disk to a sharp edge because any degradation will make it unacceptable.
Referenced Documents purchase separately The documents listed below are referenced within the subject standard but are not provided as part of the standard. Automatic equipment should be used to control the voltage rate of rise because of the difficulty of maintaining a uniform voltage rise manually.
Obtain the new mean breakdown value for the ten breakdowns. If the sample shows evidence of free water, the dielectric breakdown test should be waived, and the sample shall be reported as unsatisfactory.
The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Size px x x x x These examples represent samples that may have large differences between replicate tests. A superscript epsilon e indicates an editorial change since the last revision or reapproval. When testing high-viscosity liquids in this range, the sample should be allowed to stand until it reaches room temperature.
Apply the test voltage as specified in Section 4 until operation of the interrupting equipment. The equipment should produce a straight-line voltage-time curve over the operating range of the equipment.
Calibrate and label automatic controls in terms of rate-of-rise. If the breakdown voltage is judged in the proper range for the sample with a known breakdown value, the test cup is prepared for testing other samples. This test method should be used as recommended by professional organization standards such as IEEE C Prior to starting the test, the sample shall be inspected for the presence of moisture, sludge, metallic particles, or other foreign matter.
The voltage stress distribution between the parallel disk electrodes used in this test method are quasi-uniform and there is substantial stress concentration at the sharp edges of the flat disk faces. Resurfacing may be necessary in order to remove deep pit marks or edge damage.
This standard is subject to revision at any time by the responsible technical committee and must be reviewed every wstm years and if not revised, either reapproved or withdrawn. The breakdown test uses ac voltage in the power-frequency range from 45 to 65 Hz.
Procedure A may be used once the single operator precision of It is important to avoid touching the electrodes or the cleaned gage with the fingers or with portions of the tissue paper or chamois that have been in contact with the hands. Record on the label of the sample container identification of the device from which the sample was obtained, the date, and temperature of the sample at the time of collection Note 1. The use of Procedure B will result in a more d77 value of breakdown voltage when testing such liquids.
Link to Active This link will always route to the current Active version of the standard. The mean of the five breakdowns may be reported as the breakdown s877, provided the range criteria of Note the sharp edge fits into the radius gage and only one side of the gage fits up against the disk while the other side has considerable space.
Current edition approved Oct. Procedure B, modified in accordance with Section 17 of Test Methods Dis acceptable for testing silicone dielectric liquids if the requirements of 1. Procedure A may be used once the single operator precision of has been demonstrated. Take care to avoid touching the electrodes or the inside of the 8d77 after cleaning.
The power-frequency breakdown voltage of a liquid is reduced by the presence of contaminants such as cellulosic fibers, conducting particles, dirt, and water. It is d877 responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
All residue from the buffing must be removed before the electrodes are reinstalled in the test cup. Alternate procedures utilizing electrode shapes and configurations similar to those in the apparatus and in Test Method D should be used for oil-filled equipment utilizing well-rounded and insulated electrodes.
The top of the cup shall be maintained at least We need your help to maintenance this website.
The use of Procedure B will result in a more accurate value of breakdown voltage when testing such liquids.