63 A MCCB with 187 kA interrupting capacity — fits the high-fault panel
The Siemens SENTRON 3VA2063-5HN36-0JH0 is a 3-pole molded case circuit breaker rated for 63 A continuous current at 40 °C, with an interrupting capacity of 187 kA at 240 V AC. That 187 kA figure means it can safely clear a fault at full short-circuit current without the arc flashing over to adjacent buswork — critical for main or feeder positions in high-capacity switchboards where upstream transformer impedance is low. The 121 kA at 415 V and 79 kA at 500 V confirm it holds up under European 400 V line-to-line service. At 690 V the rating drops to 3.4 kA, so this is not the breaker for a 690 V motor center; keep it on 240–500 V distribution. The electronic trip unit is an ETU350, a line-protection (non-selectivity-optimized) curve that trips on overload and short-circuit without the intentional delay of a selective release. That makes it a straightforward fit for feeder or branch positions where you want fast clearing, not staged coordination. No undervoltage release, no phase-failure detection, no communication module — this is a clean, no-frills breaker for standard distribution panels where the protection logic lives in the trip unit alone.
Thermal derating and endurance — what the 63 A rating actually means at panel ambient
The 63 A rating holds flat from 40 °C to 50 °C, which covers most ventilated enclosures. At 55 °C it derates to 60.6 A, at 60 °C to 58.3 A, and at 70 °C to 53.6 A. If the panel runs hot — say, a packed MCC next to a furnace line — size the breaker one frame step up or verify the actual ambient at the breaker mounting point. The mechanical endurance is 20,000 cycles, which is typical for a distribution MCCB; not a motor-switching duty cycle, but fine for infrequent manual or remote operation.
Auxiliary contacts and shunt trip — what the 3VA2063-5HN36-0JH0 carries onboard
Factory-fitted with two auxiliary switches plus one trip-alarm switch (the HQ configuration). That gives you two form-C contacts for status feedback (open/closed) and a dedicated alarm contact that changes state only on a trip event — useful for remote annunciation or a PLC input that distinguishes a manual open from a fault. The shunt trip (STL) is included for remote tripping via a control voltage; the integrated auxiliary trip module is order code 3VA9688-0BL32 if you need a replacement. The basic switch assembly (the removable switching mechanism) is 3VA2063-5HN36-0AA0.
Physical fit — 105 mm wide, 181 mm tall, 86 mm deep
The breaker occupies a 105 mm wide by 181 mm tall footprint, with a depth of 86 mm from the mounting surface to the front of the handle. That is a standard 3-pole MCCB envelope for this current class; it will drop into most SENTRON 3VA panelboard or enclosure cutouts without modification. The 105 mm width is the critical dimension for multi-breaker groupings — verify the busbar center-to-center spacing matches if you are replacing an existing unit.