Ratings and fit
The Siemens 3VM1163-3EE36-0AA2 is an IEC frame 160 molded-case circuit breaker, 3-pole, rated In=63A with a breaking capacity Icu=25kA at 415V AC. That 25kA rating under the class N designation means it's sized for downstream distribution panels where fault currents stay under that threshold — not for main service entrance duty where 50kA or higher is typical. Overload protection is adjustable via the TM220 thermal-magnetic trip unit: Ir from 44A to 63A, so you set it to match the cable or load continuous current, not the breaker frame. Short-circuit magnetic pickup is fixed at Ii=10 x In, or 630A, which keeps it selective with downstream MCBs on most lighting and small motor circuits.