GB/T 5095.2-1997 Electromechanical components for electronic equipment Basic testing procedures and measuring methods-Part 2: General examination,electrical continuity and contact resistance tests,insulation tests and voltage stress tests
Electromechanical components for electronic equipment Basic testing procedures and measuring methods-Part 2: General examination,electrical continuity and contact resistance tests,insulation tests and voltage stress tests
The tests contained herein, when required by the detail specification, shall be used for electromechanical components within the scope of Technical Committee No. 48 . They may also be used for similar devices when specified in a detail specification.
1 Test 1a: Visual Examination
1.1 Object
The object of this test is to detail standard methods for the visual examination of electromechanical components within the scope of Technical Committee No. 48.
1.2 General
The visual examination checks identification, appearance, workmanship and finish of an item against the relevant specification. Optical aids, as specified in Sub-clause 1.4; should be used when specified by the detail specification.
The visual examination is to a certain extent a subjective method. Care must be taken to come to a fair judgement. Defects, deviations from a given standard or changes due to stresses must be carefully differentiated according to their importance or significance.
1.3 Features to be examined
The following features shall be examined:
a) workmanship and finish;
b) marking;
c) materials;
d) surface finish, for example:
- traces of corrosion;
- colour (comparison with applicable colour standards or samples;
- degree of lustre (comparison with applicable standard, for example Boll's scale or sample);
- roughness, grooves, waves, scratches, furrows, holes, pores, depressions, crests, scales, cracks, burrs, flash, etc.;
- foreign material in and on the surface.
e) internal conditions of translucent materials (for example cavities, gaseous inclusions and flow lines, including inclusions of foreign matter);
f) condition and location of a lubricant (as far as can be visually ascertained);
g) loosened and detached parts (especially after stress).
1.4 Method of visual examination
The visual examination shall be carried out by one of the following methods:
a) with the naked eye (normal strength of vision, normal colour perception, at the most favourable viewing distance and with suitable illumination); or
b) with magnifiers, if specified.
For the purpose of this standard, special methods, for example using polarized light (for observing internal tensions in materials) or other indicators (for observing internal material cracks or pores), are not permitted unless explicitly required by the detail specification.
1.5 Details to be specified
GB/T 5095.2-1997 The following standards are cited：
GB/T 5095.2-1997 Cited by the following standards：
