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You test, and still devices including transformers, semiconductors, circuit boards, motors, and inductors fail. A Southwest Research Institute study says to check the wires. Although many mechanisms can cause a wire to fail, each one leaves a signature that helps engineers and failure analysts diagnose the environmental factors and failure cause or causes. So, how do you track failures?
Stranded wire is spliced on long runs. The stranding machines that join groups of wire togeather turn at high speed while the wires are pulled thru the machine providing the tiwst. Sometime the welds or splices as they call them in the wire industry dont hold. Sparks inside a sheilded strands can degrade the other strands causing failures. Even if company order wire with no splices good luck. People running 10 to 20 machines get confused to which ones get splices and the ones that don't. An order for NO splices requires each break to bE HAND PULLED pulled all the way thru a stranding machine 20 to 30 feet and treaded every 4 or 5 ft thru rollers and guide tubes instead they weld (splice) the break mark it and start the machine to pull the splice thru wher it is cut out and a bew reall started. This is much easier than pulling the splice by hand, but for what ever reason operators miss splices or the company makes changing out reels a pain so operators will ignor a few breaks.
How would you track wire when you don't know what you have. You can pass a current thru it to discover exactly how many splices or welds you have in a cable length.
If you never do anything you never have problems.
I think what SRI is saying is to do a post-mortem on cable or device failures -- then see if you can track those back to problems i your system or with the cable itself.
As for testing up-front on the cable...you could specify a stress test (expensive) as is done with some high power cable. The post-mortem with regular feedback to you cable vendor usually gets some results (the squeaky wheel concept). But you need to back up your claims.