What it is and what it does
The Siemens SENTRON 3VA1110-4FE42-0AA0 is a 4-pole molded case circuit breaker (MCCB) rated for line protection, carrying a continuous current Iu of 100 A. It uses a TM220 thermal-magnetic overcurrent release — the thermal element handles overloads, the magnetic element clears short-circuits — and is built for distribution panels where a 4-wire (3-phase + neutral) feed needs coordinated protection in one compact package.
Breaking capacity — what the numbers mean for your panel
This MCCB delivers 121 kA at 240 V AC, 76 kA at 415 V AC, and 53 kA at 440 V AC. At 500 V and 690 V AC it still holds 11.9 kA. Those figures are the interrupting capacity — the maximum fault current the breaker can safely clear without welding contacts or rupturing the case. For a 100 A frame, 121 kA at 240 V is high-range; it means this breaker can sit on a transformer secondary or a high-capacity bus where available fault current is substantial, without needing a current-limiting upstream device.
Thermal derating — don't size by the 100 A label alone
The 100 A rating holds from 40 °C through 50 °C. At 55 °C it derates to 98 A, at 60 °C to 96 A, at 65 °C to 94 A, and at 70 °C to 91 A. If this breaker lands in a warm enclosure — near transformers, drives, or in a non-climate-controlled electrical room — use the 55 °C or 60 °C column for sizing. The TM220 release compensates thermally, so the trip curve shifts with ambient; the continuous current table is the safe conductor-sizing reference.
Mounting and integration
The 3VA1110-4FE42-0AA0 measures 130 mm high, 101.6 mm wide, and 70 mm deep. It mounts on a DIN rail or directly to a backplate via screw terminals. The front face carries IP40 protection — fine for a dry indoor panel, but keep it behind a gland plate or enclosure door if washdown or dust is present. The 4-pole footprint is wider than a 3-pole MCCB; verify the DIN-rail space in your enclosure before cutting the backplate.