The Siemens 3VA1063-2ED36-0JH0 is a SENTRON molded case circuit breaker (MCCB) built for line protection in distribution panels. Three poles, rated 63 A continuously at 40 °C, with an 800 V rated insulation voltage — that's the backbone for a feeder or a large motor branch circuit in a 400 V industrial network. The 52.5 kA breaking capacity at 240 V tells you it handles high-fault points without cascading upstream; at 415 V it still interrupts 32 kA, which covers most secondary substation scenarios. The 70 mm depth and 76.2 mm width fit standard panel footprints, and the shunt trip (STL) auxiliary release gives remote tripping capability for emergency-stop or process-interlock circuits.
Current derating and thermal limits
The 63 A rating holds flat from 40 °C to 50 °C — no derating needed in a typical ventilated enclosure. Above that it drops gradually: 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 hot from adjacent drives or transformers, size the load at the 58 A floor to avoid nuisance tripping. Maximum power loss is 17.3 W, which matters for thermal budgeting in a sealed gland plate.
Breaking capacity by voltage
Breaking capacity drops as system voltage rises — that's the physics of arc extinction. At 240 V it's 52.5 kA; at 415 V it's 32 kA; at 440 V it's 13.6 kA; at 500 V and 690 V it's 7.5 kA. For a 400 V panel with a transformer rating under 2 MVA, the 32 kA figure usually gives enough SCCR headroom. If your available fault current exceeds that, step up to a higher-rated frame in the 3VA family.
Auxiliary switching and trip indication
This MCCB ships with two auxiliary switches plus one trip alarm switch (HQ configuration) — enough for remote status monitoring of the breaker position and a separate fault signal. The shunt trip (STL) auxiliary release lets you trip the breaker from a remote pushbutton or a safety PLC output. No undervoltage release is fitted; if you need UVR for machine-safety disconnection, that's a different variant. Trip indicator and voltage trigger are present, so the local flag shows a trip event even if the alarm contact isn't wired.
The 3VA1063-2ED36-0JH0 mounts on a DIN rail or panel-mount via the supplied base. Depth is 70 mm, width 76.2 mm (3 inches), height 130 mm — that's a compact footprint for a 63 A MCCB with auxiliary switches. The shunt trip wiring requires a separate control voltage; verify polarity on the STL coil before energizing. Panel builders should account for the 17.3 W heat dissipation when calculating enclosure ventilation.