What this MCCB carries
The Siemens 3VA1063-2ED42-0BA0 is a SENTRON molded case circuit breaker (MCCB) rated 63 A at 40 °C, with the TM210 thermal-magnetic overcurrent release — meaning the thermal pickup is fixed at 63 A and the magnetic short-circuit pickup is 10× In (630 A). That makes it a straight line-protection breaker, not a motor-protection or adjustable version; you spec it for feeder or distribution circuits where the load current is known and stable. It is a 4-pole unit with an undervoltage release (UVR) built in — the UVR trips the breaker when supply voltage drops below a set threshold, which is standard for emergency-stop or undervoltage protection schemes in European panel designs. The UVR is the design-of-auxiliary-release type, so it's factory-integrated, not a field-add accessory. Breaking capacity is voltage-dependent: 52.5 kA at 240 V, 32 kA at 415 V, 13.6 kA at 440 V, and 7.5 kA at both 500 V and 690 V. At 415 V — common for three-phase distribution in many markets — the 32 kA rating covers most industrial transformer-fed fault levels. The 690 V figure (7.5 kA) is useful for mining or marine applications where the line-to-line voltage is higher.
Thermal derating and panel fit
The breaker holds its full 63 A rating from 40 °C up to 50 °C, then derates linearly: 62 A at 55 °C, 61 A at 60 °C, 60 A at 65 °C, and 58 A at 70 °C. If your panel ambient runs at 55 °C or higher, you lose 1–5 A of headroom — factor that into the feeder sizing, especially if the panel is tightly packed or near heat sources. Maximum power loss is 19.8 W at rated load. That's moderate for a 63 A 4-pole MCCB — expect some heat rise inside the enclosure, but it won't drive a ventilation requirement unless the panel is densely populated with other high-loss devices.