ASTM F1662-95(2002)

NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
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Designation: F 1662 – 95 (Reapproved 2002)
Standard Test Method for
Verifying the Specified Dielectric Withstand Voltage of a
Membrane Switch
This standard is issued under the fixed designation F 1662; 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 (e) indicates an editorial change since the last revision or reapproval.
1. Scope 5. Apparatus
1.1 This test method covers the verification of a specified 5.1 Electric Device, suitable to provide a controlled dc or ac
dielectric withstand voltage of a membrane switch. voltage.
2. Terminology 6. Procedure
2.1 Definitions: 6.1 Pretest Setup:
2.1.1 dielectric withstand voltage—the maximum voltage a 6.1.1 Measure the insulation resistance between the two test
dielectric can withstand without a visual change from a voltage points. Record insulation resistance as R .
i
discharge or specified change of insulation resistance, or both. 6.1.2 Connect two test points on the switch assembly to the
2.1.2 insulation resistance, R—the electrical resistance be- voltage source.
tween test points. 6.2 In-Process Test—Constant Voltage Method:
2.1.3 membrane switch—a momentary switching device in 6.2.1 Adjust voltage and frequency to a specified level.
which at least one contact is on, or made of, a flexible 6.2.2 Apply voltage to switch assembly for a specified
substrate. interval.
2.1.4 test points—two preselected mutually insulated loca- 6.3 In Process Test—Ramp Voltage Method:
tions on switch assembly. 6.3.1 Set the following parameters to specified levels (if
applicable):
3. Significance and Use
6.3.1.1 Voltage ramp rate, and
3.1 Dielectric withstand voltage testing is useful for design 6.3.1.2 Maximum ramp voltage.
verification, quality control of materials, and workmanship.
6.3.2 Perform test.
3.2 This test is designed to determine product integrity and 6.4 Disconnect switch assembly from power supply.
resistance at voltage levels that exceed normal operating levels.
6.5 Inspect switch assembly for visual change.
3.3 Specific areas of testing are, but not limited to:
6.6 Measure the insulation resistance using the same proce-
3.3.1 Conductor/dielectric/conductor crossing point, dure used in 6.1.1.
3.3.2 Close proximity of conductors, and
6.7 Record insulation resistance as R .
f
3.3.3 Any other conductive surface such as shielding or
7. Calculation
metal backing panel.
3.4 Dielectric withstand voltage testing may be destructive 7.1 Calculate the change in the insulation resistance as
and units that have been tested should be considered unreliable follows:
for future use.
DR 5 Change in Insulation Resistance 5 ? R 2 R ?
i f
4. Int
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