MCCB for 480 V distribution — 65 kA SCCR, fixed-trip TM210
The Siemens 3VA4120-6ED34-3AA0 is a 3-pole molded case circuit breaker in the 3VA4 UL Frame 125 platform, rated 65 kA at 480 V AC — high enough for most North American panelboard main or feeder positions without cascading upstream. The TM210 thermal-magnetic trip unit ships with a fixed overload setting of Ir = 20 A and a fixed short-circuit pickup of Ii = 15 × In (300 A magnetic), so it arrives ready for a 20 A branch circuit; no field-adjustment dials to mis-set. This is a C-class make-to-order product (Product class C), meaning each unit is built to a specific order and cannot be returned or re-stocked — confirm the BOM line before committing. The 65 kA interrupting rating at 480 V is the headline number for coordination studies: it tells the panel designer that this breaker can clear a bolted fault up to that level without bursting, so it can sit downstream of a transformer or upstream of a distribution block without needing a current-limiting fuse ahead of it. The fixed Ir and Ii eliminate the trip-unit as a variable during arc-flash labeling — what you order is what you get on the label.