Siemens 3VA2225-4JQ42-0AA0 — 250 A SENTRON MCCB with ETU560 Trip Unit
It carries the ETU560 electronic trip unit, which supports adjustable N-conductor protection (OFF, 20% to 100%) and includes a communication function for integration into monitored distribution systems. Breaking capacity is specified across multiple voltage levels: 121 kA at 240 V, 75.6 kA at both 415 V and 440 V, 52.5 kA at 500 V, and 4.5 kA at 690 V. This selectivity profile suits it for main or branch feeder duty in low-voltage switchgear where high fault currents at lower voltages are expected.
Thermal Derating and Ambient Constraints
Above that, derating applies linearly: 238 A at 55 °C, 225 A at 60 °C, 213 A at 65 °C, and 200 A at 70 °C. For a panel OEM wireman, this means the breaker can be installed in a warm enclosure without immediate down-rating, provided the internal ambient stays at or below 50 °C. Above that, the load schedule must be adjusted. The IP40 front protection keeps debris and accidental contact out of the breaker face, but the body is not sealed against washdown — install in a dry location or a secondary enclosure.
Dimensions: 181 mm height, 140 mm width, 86 mm depth. The 140 mm width across four poles is the key panel-space constraint — standard for a 4-pole MCCB in this frame size. Depth of 86 mm leaves clearance for rear bus connections and wiring troughs in a typical 600 mm deep enclosure.