The Siemens 3VA2450-5HK32-0AC0 is a current-production IEC frame 630 molded-case circuit breaker in the 3VA2 series, carrying a 55 kA interrupting rating at 415 V (class M). The ETU340 electronic trip unit gives you adjustable overload protection from 200 A to 500 A and a fixed short-circuit pickup of 14 x In (7 kA at the 500 A rating), which is a deliberate selectivity band for motor feeder or transformer secondary protection.
Frame 630 means the physical size and busbar pattern match the 630 A frame — the In rating of 500 A is a trip-unit derate within that frame, so the breaker body and terminals are rated for 630 A continuous. The busbar connection variant (not plug-in or rear-terminal) is the one you want for a fixed-mounted panel where the breaker bolts directly to a busbar stack. Two changeover auxiliary switches (form C) are built in, giving you NO/NC status feedback without adding external aux blocks — handy for remote indication or PLC input without extra wiring.
Deployment context
This is a panel-mounted breaker — it bolts into a switchboard or distribution enclosure on the busbar system, not a snap-on DIN rail mount. The 55 kA class M rating is typical for main or tie breakers in 400 V industrial switchboards where the available fault current sits in the 50–65 kA range. The ETU340 is the standard electronic trip for line protection (cable/feeder protection), not motor protection — no motor-starting curve or ground-fault option in this variant.