Also should be clear by now that about the time a particular design/product line is obsoleted is the point where we know what expected lifetimes are! You make your best guess. Manufacturers try to stick to known/good product designs but you just don’t know.
Case in point is the biggest recent innovation in circuit breakers is the magnetic actuator. In a VCB it can be built with just one moving part. Tavrida makes an incredibly compact MV VCB based on this. ABB started using it much earlier with their Mag Gard but it has a bunch more linkages. In theory these should have 40+ year life and the drastically simpler mechanism should be superior to traditional latching designs. Neither company “invented” it. A little known British engineering company did. So is it superior? For that matter is the Tavrida going to hold up over time? We’ve only got 10-15 years if operating data but it’s looking good so far.
A counter example exists. People said/felt the same way about solid state protection relays too. On paper electronic components should beat out an induction disk electro-mechanical mechanism. Yet they started failing in only 10 years. I’ve even seen just plain bad designs. GE Wavepro breakers have had contact tips literally fall off the breakers in 18 months of service in more than one facility.
