Siemens 3VA1112-6EF36-0CH0 — SENTRON MCCB, 125 A, 3-Pole Line Protection
The Siemens 3VA1112-6EF36-0CH0 is a SENTRON molded case circuit breaker (MCCB) rated for line protection, carrying a continuous current of 125 A at 40 °C through 50 °C, derating to 114 A at 70 °C. The 3-pole unit delivers a breaking capacity of 220 kA at 240 VAC, 154 kA at 415 VAC, and 75.6 kA at 440 VAC — figures that govern its suitability for high-fault panels where SCCR coordination is critical. An undervoltage release (UVR) is integrated per the design, and the auxiliary switch configuration includes two auxiliary switches plus one trip alarm switch (HQ). The rated insulation voltage is 800 V, and maximum power loss is 30.6 W.
Breaking Capacity and Selectivity
The 220 kA at 240 V is the headline interrupting rating; the 154 kA at 415 V and 75.6 kA at 440 V are the values that matter for European 400 VAC panels. At 500 V and 690 V the rating drops to 17 kA — still sufficient for most motor branch circuits at those voltages, but the margin narrows. These are the figures a site electrical engineer uses for arc-flash incident-energy calculations and selective coordination studies.
Thermal Derating and Panel Integration
The 125 A rating holds flat from 40 °C to 50 °C, then derates linearly to 114 A at 70 °C. For a panel OEM wiring a 125 A MCCB into a 76.2 mm wide (3 in) DIN-rail footprint, the 70 mm depth and 130 mm height leave clearance for gland plates and busbar routing. The operating temperature range is -25 °C to 70 °C, with storage from -40 °C to 80 °C.