As you mentioned, one of the biggest factors we look for is ruggedness and the ability of the connector to withstand insertion forces without breakage. Recently, we switched from a surface mount connector to a through hole connector in order to improve durability in the field.
Jane, to my best knowledge most of the device manufacturing companies are just like a system integrator. They had outsourced all the major component development and manufacturing to third party vendors and finally they will assembly/integrated all such components under their case (outer covering) with brand name.
This is a nice list of technical issues that should be considered. Datasheets are usually accurate, but many companies publish data in a way that presents their product in the best possible light. Knowing what to look for beforehand is an important part of choosing the right connector.
Connectors and harnesses are big business. However, I would like to see some standardization in the medical industry. I worked for a company making some medical products. They literally said that they made a proprietary connector so the industry would have to buy more from them at high prices.
I was disappointed at their attitude towards their life saving devices. I didn't stay there for that and other reasons. Since then, I have been a big fan of standardization and open source.
Jane, isn't it amazing that something so prosaic as a connector becomes important? It is especially true in high reliability environments. Whenever I see a site or magazine geared toward the military and aerospace markets, I see lots of ads for connectors. These are essentially the same ads that have been running for many years, but the importance is still there.
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