The Siemens 3VA1112-5MH36-0AF0 is a 3-pole IEC frame 160 circuit breaker rated 125 A with a 55 kA breaking capacity (Icu) at 415 V, placing it in breaking capacity class M. This is a motor-starting protection variant (TM120M, AM) — it provides short-circuit protection with an adjustable instantaneous trip (Ii) from 5 to 15 times In, but no overload protection, so it pairs with a separate overload relay for motor branch circuits.
The adjustable instantaneous trip (5–15 x In) lets you set the magnetic trip threshold between 625 A and 1875 A, which you coordinate with the downstream motor's locked-rotor current and upstream protective device. Because it omits overload protection, you must add a separate thermal overload relay (e.g., Siemens 3RU2 series) in the motor starter assembly.
Panel Integration
Clamp terminals accept conductors without lugging, which speeds panel wiring.