This is the blog of Ronald Bartels that wanders on and off the subject of problem management (that is how it started), but it is best described by Ray who says this is Daddy's thoughts! Like the best music is from the Eighties and a wee dram helps in solving most inconveniences.
Low-voltage air circuit breakers: the case for preventive maintenance
It has also been found that, if a circuit breaker is not tested and maintained according to the manufacturer’s instructions, the failure rate could be very high. An IEEE study shows that failure probability could reach 50% in five years and that 73% of all circuit breaker failures are disruptive to plant operations and require the technical teams’ emergency efforts to rectify. All of this can be reduced greatly if preventive maintenance is performed.