2,315
edits
Changes
→Failure Analysis
*Signal Relays (Low Current Relays)
The DC load conditions are specified in the relevant standards (for ex. Telecom Specifications).
*Switching of “dry circuits” with monitoring of the contact resistance, in some cases at elevated temperatures
Results of relay life testing using different contact materials are illustrated as an example in <xr id="fig:Automotive relays under motor load"/><!--(Fig. 13.9)-->. For each contact material, 10 relays were tested under the prescribed motor load until a failure due to non-opening was detected. For this specific load condition AgNiO15 was found to be the best suited contact material.
<div class="multiple-images">
<figure id="fig:Principle and sequence of testing with electronic load simulation">
[[File:Principle and sequence of testing with electronic load simulation.jpg|right|thumb|Figure 4: Principle and sequence of testing with electronic load simulation]]
</figure>
<figure id="fig:Automotive relays under motor load">
[[File:Automotive relays under motor load.jpg|right|thumb|Figure 5: Automotive relays under motor load: Results of electrical life testing using different contact materials]]
</figure>
</div>
<div class="clear"></div>
<br style="clear:both;"/>
===<!--13.3.6-->Failure Analysis===
The full clarification of causes for switching device failures, for example relays, is most important for quality assurance. As a starting point, the full history of the relay, such as electrical load, environmental conditions etc. must be recorded. The process flow chart in (<xr id="fig:Flow diagram for evaluation of failure cause in switching devices for communications technology"/><!--(Fig. 13.10)-->) clearly describes a proven way to conduct a failure analysis.Following all procedures of such a failure evaluation carefully, the root cause of the defect can most likely be established in order to implement preventive measures limiting future occurrences.
<figure id="fig:Flow diagram for evaluation of failure cause in switching devices for communications technology">
[[File:Flow diagram for evaluation of failure cause in switching devices for communications technology.jpg|rightleft|thumb|Figure 6: Flow diagram for evaluation of failure cause in switching devices for communications technology]]
</figure>
==References==
