An electrical component manufacturer noted that some circuit breakers were failing at lower current levels than expected during periodic QC checks. Problems with internal assembly were suspected but disassembly would disturb internal components, making failure analysis impossible.
The company's internal QC testing culled out nonconforming parts, but couldn't determine what went wrong. X-ray radiography was used to view internal assembly in-situ and identify the problem - improper wire routing within the assembly caused early failure.
Inside view of a typical breaker showing the variety of materials and interconnected components.