Larry Stutts wrote:
I recently read what the annual PM requirements are for circuit breakers and the testing requirements are for circuit breakers that have tripped under load.
I have been in a lot of plants, and I can't say for sure that the manufacturer's testing requirements are observed in the majority of facilities I have been in.
Testing is just part of "properly maintained". Lubrication, verification of factory adjustments, and at some point full refirbishment are all requirements from the OEM's to be properly maintained. The only facilities that really do this are nuclear plants and some high end facilities (Data centers, NASA, etc...)