The Siemens 3VA1220-4EF42-0HA0 is a SENTRON molded case circuit breaker (MCCB) designed for line protection in distribution panels. It carries a 200 A continuous rating at 40 °C across all four poles, with a thermal-magnetic TM240 overcurrent release that handles both overload and short-circuit conditions without a separate trip indicator. The interrupting ratings are substantial: 121 kA at 240 V AC, 75.6 kA at 415 V, 52.5 kA at 440 V, 17 kA at 500 V, and 11.9 kA at 690 V — so it can be applied in high-fault-capacity main or feeder positions where SCCR coordination matters. This unit includes a factory-installed shunt trip (STL) auxiliary release, meaning it can be remotely tripped via a control voltage for emergency stop or load-shedding schemes. The insulation voltage is rated 800 V, and the breaker measures 140 mm wide by 158 mm tall by 70 mm deep — a standard 4-pole MCCB footprint that fits SENTRON panelboard and switchboard mounting patterns.
Thermal derating and ambient limits
The 200 A rating holds steady from 40 °C up to 50 °C. Above that, derating is linear: 194 A at 55 °C, 188 A at 60 °C, 182 A at 65 °C, and 176 A at 70 °C. If the panel ambient runs hot — say, adjacent to a transformer or in a non-ventilated enclosure — use the 55 °C or 60 °C column for sizing. The operating temperature range is -25 °C to 70 °C, with storage from -40 °C to 80 °C. Maximum power loss at rated load is 42 W, which matters for thermal budgeting inside a sealed cabinet.