The Siemens 3VA2063-5KQ32-0AA0 is a SENTRON molded case circuit breaker rated for 63 A continuous current across the full 40 °C to 70 °C ambient range — no derating needed up to that ceiling. Its 187 kA breaking capacity at 240 V handles high-fault utility feeds without cascading upstream breakers, and the ETU860 electronic trip unit gives you adjustable time-current curves for selective coordination. Ground fault monitoring is built in via summation current formation on the line conductor, so this one device covers both overcurrent and ground-fault protection in a single panel slot.
What the ratings mean on the panel
At 105 mm wide and 86 mm deep, this 3-pole MCCB fits standard SENTRON mounting footprints — bolts into the same bus-bar pattern as the 3VA2 family. The 63 A frame carries the same interrupting ratings whether the panel ambient sits at 40 °C or 70 °C (–), so you don't lose headroom in a hot enclosure. IP40 on the front means it's protected against tools and wires above 1 mm, standard for switchboard interiors; no washdown rating, so keep it inside the cabinet.
Field-service note
The 5.4 W maximum power loss is low enough that you don't need forced ventilation around it in a typical panel. Mechanical endurance is 20,000 operations — that's a lifetime of routine switching, not a daily cycling device. If you're swapping one in on site, the 181 mm height clears most standard distribution sections. No special tools needed beyond a Torx driver for the line and load lugs.