You know and trust the major brands of breakers, fuses, and motors available in the market. If you install a 200A breaker, you have confidence knowing it's not going to blow up with a 150A load or fail to open upon overload. Unfortunately, there's a problem that can turn this trust on its head. That problem is the imposter part.
The availability of counterfeit products is well known. For example, fake breakers may look and feel very much like the real deal. However, their internal components are inferior, underrated, and, most likely, untested. This may result in a repair ending up more like sabotage. While this is certainly not the intent of the purchasing agent or electrician, it's what happens when parts are bought without the proper due diligence.
Your first line of defense is to establish a relationship with a reputable electrical distributor, retailer, remanufacturing company, or surplus equipment dealer. These firms have processes in place to prevent counterfeit parts from entering their system.
In Part 2, we'll look at other ways to prevent disaster by counterfeit.