Well pump trips breaker at start, but then starts when breaker reset
Excellent points. I work with specifications and qualified components in the marine industry, so I am aware of compliance requirements.
The breaker panel is over 30 years old. It lists only breakers made by the same manufacturer instead of to a specification or testing criteria.
I suspect that in this case, the other manufacturers of circuit breakers have created their equivalents so they could get in on the market. Not sure I can resurrect the total historical picture, or really want to.
In my work I often deal with similar issues. Manufacturers want you to use their products over a competitor's, so they list only their products for replacement. Or, other companies develop equal or better products, either before or after, then the installed equipment.
In my particular case, by virtue of experiencing installation, I know the fit is good and contacts are tight. With regard to contact area, the physics behind the rating will govern the design. The GE breaker is UL approved for 20A. Because of this approval, I know that all of the parameters governing design, including contact area, are sufficient.
Yes, one should not carelessly substitute components. Thanks for the insight.