What this 125A MCCB is and where it fits
The Siemens 3VA1112-5MH36-0AB0 is a 3-pole IEC frame 160 molded-case circuit breaker rated 125 A with a breaking capacity class M of Icu=55 kA at 415 V. It carries the TM120M thermal-magnetic release tuned for starter protection — note the 'without overload protection' qualifier in the order-code suffix, meaning this variant is configured for short-circuit protection only (Ii adjustable 5...15 x In), intended to pair with a separate overload relay in a motor starter assembly. The clamp-type terminals accept standard power conductors, and the factory-fitted 2 auxiliary switches (HP type) provide status feedback to the PLC or safety circuit.
What the ratings mean for the panel
The 55 kA Icu at 415 V is the ultimate short-circuit breaking capacity — the breaker can safely interrupt a fault up to that level once and remain functional. For motor starter duty, the adjustable short-circuit release (Ii = 5...15 x In, so 625...1875 A) lets you coordinate with the downstream contactor and overload relay, avoiding nuisance trips on inrush while still protecting the cable. The IEC frame 160 means the physical footprint and terminal spacing match standard 160 A frame accessories (busbars, plug-in bases, door interlocks).
Deployment context
This MCCB mounts in a distribution panel or motor control center on a DIN rail or mounting plate. The clamp terminals accept copper or aluminum conductors typical of 125 A motor feeders. The two auxiliary switches (HP) give the PLC a positive indication of breaker state — useful for safety interlocks or remote monitoring in a motor control scheme.