What this MCCB carries and where it lands
The Siemens SENTRON 3VA1112-6MH36-0AF0 is a 3-pole molded case circuit breaker (MCCB) rated for starter protection duty — meaning it's built to sit ahead of a motor starter or contactor, handling both overload and short-circuit interruption in one package. Continuous current is 125 A at 40 °C, and it holds that rating all the way to 50 °C before it starts to derate: 122 A at 55 °C, 120 A at 60 °C, 117 A at 65 °C, and 114 A at 70 °C. That's a shallow derate curve, so you don't lose much capacity in a warm enclosure. Breaking capacity is the headline: 220 kA at 240 V, 154 kA at 415 V, 75.6 kA at 440 V, and 8.5 kA at 690 V. At 415 V — common for industrial three-phase — that 154 kA gives you serious fault-current headroom. The TM120M thermal-magnetic release handles the overload curve; no undervoltage release, no ground-fault monitoring, no communication module on this variant. Just a clean, hard-wired MCCB with a trip indicator and a 1 aux + 1 trip alarm switch (HQ version) for status feedback to the PLC.
DIN-rail fit and panel integration
Footprint is 130 mm high × 76.2 mm wide × 70 mm deep. That's a standard SENTRON 3VA form factor — it clips onto the DIN rail and leaves room for side-by-side mounting with other 3VA breakers. The IP40 front rating means it's fine inside a closed panel; no washdown rating, so don't put it on the outside of a food-grade cabinet.
What the ratings mean for your BOM line
Starter-protection variant with TM120M release and auxiliary contacts. Footprint 130 × 76.2 × 70 mm matches 3VA1112 frame. Verify trip unit before replacing a 3VA1112-5EF32-0CA0.
Operating range and storage limits
Operates from -25 °C to 70 °C; storage -40 °C to 80 °C. Rated insulation voltage 800 V, max DC operational voltage 500 V. Latching endurance 15,000 cycles.