What the 63 A rating and 76 kA breaking capacity mean for fit
The Siemens SENTRON 3VM1163-3EE32-0AA0 is a 3-pole molded case circuit breaker (MCCB) rated for line protection, carrying 63 A continuously at 40 °C without derating. The TM220 thermal-magnetic release provides inverse-time overload protection and instantaneous short-circuit trip — the 220 designator indicates a fixed thermal pickup of 63 A and a magnetic trip threshold of 10x In (630 A), so it holds motor inrush without nuisance tripping. Breaking capacity reaches 76 kA at 240 V AC, 53 kA at 415 V, and 32 kA at 440 V; at 500 V it still interrupts 12 kA. That 76 kA at 240 V means this breaker clears high-fault currents on 240 V delta or line-to-line circuits without upstream fuses — critical for panel SCCR compliance under UL 508A.
Thermal derating and panel integration
The 63 A rating holds flat from 40 °C through 50 °C (63 A), then derates to 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 50 °C panel ambient — common in enclosed switchgear — you still get full 63 A; above that, plan for the derated value. The 70 mm depth, 76.2 mm width, and 130 mm height fit standard SENTRON panel cutouts; IP40 on the front protects against tool entry but not washdown, so mount inside a sealed enclosure in wet environments. Power loss at rated load is 17 W maximum — negligible for panel thermal budgeting.