What this breaker is and what the ratings mean for fit
The Siemens 3VA2450-7MS32-0DK0 is a 3-pole IEC frame 630 circuit breaker configured for starter protection with an ETU310M trip unit, rated In=500A, and carrying a breaking capacity class C rating of Icu=110kA at 415 V AC. That 110 kA interrupting rating at 415 V means this breaker can safely clear a fault current up to 110,000 A without failing — critical for high-fault installations like large motor control centers or transformer secondaries where available fault current is substantial. The ETU310M is a microprocessor-based trip unit; here it is set for short-circuit protection only (Ii adjustable 3...15 x In), with no overload protection function, so the breaker relies on an upstream or separate overload relay for thermal protection of the connected load.
Included accessories and integration notes
This order code includes an undervoltage release rated 208-230 V AC 50/60 Hz, a nut keeper kit, and one auxiliary switch (changeover H contact). The undervoltage release trips the breaker when control voltage drops below its dropout threshold — a standard requirement for safety circuits that must disconnect on loss of control power. The auxiliary switch provides a remote status signal (open/closed) to a PLC or indicator lamp. The nut keeper kit secures the breaker in the panel; verify gland-plate clearance for the 630 A frame size before mounting.