What this 63 A MCCB is and what it does
The Siemens 3VA1063-4ED42-0DH0 is a SENTRON molded case circuit breaker (MCCB) designed for line protection — the main feed into a panel or a branch circuit that needs a solid, coordinated overcurrent break. This is a 4-pole unit rated at 63 A continuous at 40 °C, and it holds that same 63 A all the way up to 50 °C ambient; you don't start losing headroom until 55 °C (62 A) and it's still at 58 A at 70 °C. That thermal margin matters when this breaker sits in a packed enclosure next to other heat sources. Breaking capacity is where this part earns its keep: 121 kA at 240 V, 75.6 kA at 415 V, 52.5 kA at 440 V, and 11.9 kA at both 500 V and 690 V. That tells you this is built for high-fault industrial networks — not a light-duty panelboard breaker. The rated insulation voltage is 800 V, so it's comfortable on 480/277 V or 600 V systems with healthy margin.
Panel fit: dimensions and integration
The 3VA1063-4ED42-0DH0 measures 130 mm tall, 101.6 mm wide, and 70 mm deep. That 70 mm depth is the dimension you care about for enclosure depth clearance — it's shallow enough to fit most standard 200 mm deep panels with room for wiring gutters. The 101.6 mm width is 4 inches exactly, which is the standard footprint for a 4-pole SENTRON frame at this rating. Mounting is via the standard MCCB DIN-rail or screw-mount pattern; no oddball cutout needed. Maximum power dissipation is 19.8 W. In a sealed enclosure that's not negligible — if you're stacking several of these, account for the heat rise. Operating range is -25 °C to 70 °C, storage from -40 °C to 80 °C, so it's fine for unheated warehouses or outdoor cabinets in temperate climates.
What's inside: auxiliary and release configuration
Factory-equipped with two auxiliary switches and one trip alarm switch (the HQ type). The undervoltage release (UVR) is also built in — that's the coil that drops the breaker if control voltage falls below a threshold, common in safety circuits or emergency-stop chains. The basic switch assembly carries its own order code (3VA10634ED420AA0) if you ever need to replace just the switching mechanism. No ground-fault monitoring on this variant, no communication module, no voltage-trip feature.