What this 3VA1 breaker carries
The Siemens 3VA1163-6MH32-0HC0 is a 3-pole IEC molded-case circuit breaker on the 160 A frame, fitted with a TM120M thermal-magnetic trip unit rated 63 A. Its breaking capacity class H delivers 70 kA Icu at 415 V AC — enough for high-fault utility or transformer-fed panels where SCCR headroom matters. The trip block is configured for starter protection (AM characteristic), meaning it coordinates with a contactor/overload pair rather than providing its own overload function; short-circuit pickup Ii is adjustable 5 to 15 times In. This order code includes a shunt trip (STL) release rated 12–30 V DC or 24 V AC 50/60 Hz, plus two HQ auxiliary switches for remote status indication. A nut keeper kit is factory-fitted, which simplifies panel mounting on busbar or backplate studs.
What the ratings mean for panel fit
The 70 kA Icu at 415 V means this breaker can safely interrupt faults up to that level without upstream fuses or a current-limiting device — a key spec for main or tie-breaker positions in industrial switchboards where the available fault current is high. The 63 A TM120M trip provides motor-starting inrush tolerance (AM curve) while the adjustable Ii (5–15× In) lets you fine-tune magnetic pickup to the branch load. The shunt trip coil draws from a separate 12–30 V DC or 24 V AC supply, so it can be wired to an emergency-stop relay or remote pushbutton without loading the breaker's own control circuit. The two HQ auxiliary switches change state with the main contacts, giving the PLC or annunciator a direct status signal.