Cables and Connectors and HALT
Kirk and Fred discussing the benefits and limits of using HALT for finding issues with cables and connectors, and common cause for many failures or intermittent operation in electronic hardware.
Join Kirk and Fred as they discuss the challenge of testing and finding issues with connectors and some of the common failure mechanisms that they have observed in failure analysis.
- The complexity of connectors, the many types of connectors and the many things that can cause failures.
- HALT vibration can actually mask or remove a common cause of failures in connectors, such as fretting corrosion, but thermal and vibration HALT may detect strain and wire routing issues, noting that continuous monitoring under stress is critical to defect detection.
- How cable testing may not be valid if the automated mechanical test conditions do not correlate to use stresses.
Enjoy an episode of Speaking of Reliability. Where you can join friends as they discuss reliability topics. Join us as we discuss topics ranging from design for reliability techniques, to field data analysis approaches.
For more information about Kirk’s Consulting services, please see his Accelerated Reliability Solutions website please click here
To see or purchase Kirk’s new book co-authored with John Paschkewitz, “Next Generation HALT and HASS: Robust Design of Electronics and Systems” please click on this link.
We always appreciate your feedback and questions. Thanks for listening.
Viswanatha Chenna says
Why cables are not considered in reliability prediction analysis?
Fred Schenkelberg says
First off, do not do reliability prediction analysis using parts count or part stress analysis. If using tabulated failure rates the result is pretty much meaningless and certainly does not predict future reliability performance.
When modeling the reliability performance of an item, you may consider cables as an element. Estimate via testing or field data the probability of failure distribution for the salient failure mechanisms and include that information in your model. For electrical cables, stresses like tension, abrasion, and chemical erosion/cracking may lead to shorts.
In most situations, with nominal applied stresses on the cable, as in a desk top computer, the chance of cable failure is very low – thus time spent of higher risks of failure make more sense. Each situation is different and the set of components, subsystems included in the reliability model should attempt to account for the majority of risks of failure over time.
So, if the analysis method does not include cables – that may or may not be a problem for your situation. You can always add cables if you want (and have meaningful data).