What it is and what the ratings mean
The Siemens 3VM1463-4EE42-0AA0 is a SENTRON molded case circuit breaker (MCCB) for line protection, rated 630 A continuous at 40 °C across all four poles. That 630 A holds flat through 50 °C — only starts to derate above 55 °C, dropping to 583 A at 70 °C. So for most panel environments below 50 °C, you get full rated current without a derate factor to calculate. Breaking capacity runs 121 kA at 240 V AC, 76 kA at 415 V and 440 V, and 53 kA at 500 V AC. That 121 kA at 240 V is the headline number — it tells you this breaker can clear a massive fault on a low-voltage distribution bus without welding contacts or venting arc gas into the panel. It carries a TM220 overcurrent release — thermal-magnetic, fixed, no electronic adjustment. That means the thermal element handles overload protection and the magnetic element handles short-circuit; no dip switches or rotary dials to set. The 220 designation is Siemens' internal code for the trip curve family. Rated insulation voltage Ui is 800 V, operating voltage 690 V AC, and max DC operating voltage 500 V. Four poles, so it switches all three phases plus neutral (or a fourth phase in delta systems). No undervoltage release, no shunt trip, no communication module — this is a straight thermal-magnetic breaker for basic distribution.
Where it fits
Mounts in a standard switchboard or panel enclosure. Front IP40 protection — fine for indoor distribution boards, not for washdown or outdoor exposure without a secondary enclosure. Dimensions: 248 mm tall, 184 mm wide, 110 mm deep. That 184 mm width is the panel cutout dimension to plan for; it's a 4-pole frame, so wider than a 3-pole equivalent. Maximum power loss is 193 W at full rated current. That's the heat you need to vent from the enclosure — factor it into your thermal calculation if the panel is densely packed.