The Siemens 3VA2063-4HM42-0AA0 is a SENTRON molded case circuit breaker (MCCB) rated for 63 A continuous current (Iu) across the full 40 °C to 70 °C ambient range — no derating needed up to that ceiling. It carries a 4-pole configuration with the N-conductor protection adjustable between OFF and 100 %, giving you flexibility on grounded or ungrounded systems. The ETU330 electronic trip unit handles the overcurrent release, and the interrupting ratings are substantial: 121 kA at 240 V AC, 75.6 kA at 415 V and 440 V, 52.5 kA at 500 V, and 3 kA at 690 V. That 121 kA at 240 V means this breaker can safely clear a fault on a high-capacity transformer secondary without the arc flashing over — a real consideration on industrial services where available fault current runs north of 100 kA. Rated insulation voltage is 800 V, and the operating voltage at AC goes to 690 V, so it handles 480 V and 600 V class systems with headroom.
The 3VA2063-4HM42-0AA0 measures 140 mm wide, 181 mm tall, and 86 mm deep — a standard SENTRON 3VA frame size that drops into a DIN-rail or panel-mount footprint.