63 A MCCB with 121 kA interrupting capacity — line protection variant
The Siemens SENTRON 3VA1063-4ED32-0JH0 is a 3-pole molded case circuit breaker rated for 63 A continuous at 40 °C, with a TM210 thermal-magnetic release and an integrated shunt trip (STL). It carries a 121 kA interrupting capacity at 240 V AC, derating to 75.6 kA at 415 V and 52.5 kA at 440 V — sufficient for high-fault utility feeds or transformer secondaries where fault current runs into the tens of kiloamps. The 63 A rating holds flat through 50 °C; above that it derates to 62 A at 55 °C, 61 A at 60 °C, 60 A at 65 °C, and 58 A at 70 °C, so the thermal curve is worth checking if the breaker sits in a warm enclosure. This is the line protection version (not motor protection), meaning the TM210 release is calibrated for cable and busbar protection rather than motor overload curves.
The closest sibling in the SENTRON 3VA family is the 3VA1010-2ED32-0AD0, which shares the same 3-pole frame, TM210 release, and shunt trip design. The delta is the continuous current rating: the 3VA1010 is a 100 A frame, while the 3VA1063 is a 63 A frame. Both use the same physical footprint — 70 mm deep, 76.2 mm wide, 130 mm tall — so a panel laid out for the 100 A version will accept the 63 A unit without rewiring or drilling new mounting holes. The interrupting ratings are identical across the voltage range; the only difference is the thermal trip threshold. If your BOM calls for 63 A and you have the 100 A variant available via RFQ confirmation, it will hold the line temporarily, but the overload protection won't coordinate properly with downstream 63 A feeders.
Panel integration — dimensions and auxiliaries
The breaker occupies a 70 mm × 76.2 mm footprint on the DIN rail or panel-mount adapter. The shunt trip (STL) is factory-installed, so no field wiring of an external trip coil is needed — just connect the control voltage to the STL terminals. The 2 aux + 1 alarm switch block is also pre-fitted, saving panel-builder labor. Rated insulation voltage is 800 V, and the operating range spans -25 °C to 70 °C ambient, with storage from -40 °C to 80 °C.