The Siemens SENTRON 3VA2063-6JQ42-0AA0 is a 4-pole molded case circuit breaker rated for 63 A continuous current across the full ambient range from 40 °C to 70 °C — no derating needed up to that ceiling, which simplifies panel thermal budgeting in a crowded enclosure. Its breaking capacity hits 242 kA at 240 V and 187 kA at 415 V, so it handles high-fault utility feeds without cascading upstream; the 3 kA at 690 V covers the rare 690 V distribution bus. Designed for line protection (cable and busbar feeder duty), it includes a ground-fault monitoring version that uses summation current formation on L + N, and a communication function for integration into a higher-level monitoring system. The absence of a trip indicator and undervoltage release means the buyer should verify whether those features are needed elsewhere in the BOM.
The breaker occupies 140 mm width, 181 mm height, and 86 mm depth — a standard MCCB footprint for 4-pole 63 A frames.