What this breaker is and what it does
The Siemens 3VA1163-5MH36-0BC0 is a 3-pole IEC frame 160 molded-case circuit breaker with a 55 kA breaking capacity at 415 V — class M, meaning it handles high fault currents typical of industrial distribution panels and motor branch circuits. Rated In = 63 A, it ships with a TM120M thermal-magnetic trip unit set for starter protection; note the 'without overload protection' qualifier means the thermal element is omitted, leaving only the magnetic short-circuit pickup adjustable from 5 to 15 times In. That makes this breaker a pure short-circuit protector for a motor starter combination — the overload relay handles the thermal protection separately.
What the ratings mean for fit
The 55 kA Icu at 415 V tells you this breaker can safely interrupt a fault current up to that level without welding contacts or venting arc gas — critical for panel SCCR compliance. The adjustable short-circuit pickup (5–15 x In = 315–945 A magnetic trip) lets you coordinate with downstream motor starters and avoid nuisance trips on inrush. Clamp terminals accept copper or aluminum conductors up to the frame's rated cross-section; the undervoltage release (UVR) at 24 V DC drops the breaker on loss of control voltage, standard for emergency-stop or safety circuits. Two HQ auxiliary switches provide status feedback to the PLC or HMI.