The Siemens 3VA1063-3ED36-0JA0 is a SENTRON molded case circuit breaker (MCCB) rated 63 A at 40 °C, holding that same 63 A all the way up to 50 °C before it starts a gentle thermal derating curve — 62 A at 55 °C, 61 A at 60 °C, 60 A at 65 °C, and 58 A at 70 °C. That means in a warm panel you still get nearly full rated current; no need to oversize for ambient headroom unless you're above 70 °C. The interrupting ratings tell the real story: 75.6 kA at 240 V, 52.5 kA at 415 V, 32 kA at 440 V, and 7.5 kA at both 500 V and 690 V. At 690 V the 7.5 kA is still adequate for most motor branch circuits, but verify against your transformer's through-fault capability. It's line-protection design, meaning it's sized to protect cable and bus rather than a specific motor or transformer.
The 3VA1063-3ED36-0JA0 measures 130 mm high, 76.2 mm wide, and 70 mm deep — a 3-pole frame that fits standard MCCB panel cutouts. The shunt trip is wired separately — it's not an undervoltage release, so it requires a sustained control voltage to hold the breaker closed.