What this MCCB carries — the ratings that decide the fit
The Siemens 3VA1163-5EF32-0CH0 is a SENTRON 3-pole molded case circuit breaker rated for 63 A continuous at 40 °C, with no derating needed up to 50 °C — it holds 63 A across that range. At 55 °C it still carries 62 A, and at 70 °C it's 58 A, so for a panel running warm you lose only a few amps, not a frame size. The interrupting capacity is 187 kA at 240 V, stepping down to 121 kA at 415 V, 75.6 kA at 440 V, and 17 kA at 500 V and 690 V — this is a high-breaking-capacity device sized for fault currents on large distribution transformers or close-coupled switchgear. Insulation voltage is rated 800 V, so it's comfortable on 480/277 V or 600 V systems. Power loss at full load is 19.8 W, which matters for enclosure thermal rise calculations. This variant is configured for line protection — not motor or generator protection — with an undervoltage release (UVR) built in, plus two auxiliary switches and one trip alarm switch (HQ). The UVR means the breaker trips when control voltage drops, which is standard for emergency-stop or safety-related disconnect circuits. No communication function or ground-fault monitoring on this order code, so it's a straightforward thermal-magnetic MCCB for feeder or branch-circuit protection in a panel.
Panel fit and mounting
The breaker measures 130 mm tall, 76.2 mm wide, and 70 mm deep — a 3-pole frame that fits standard Siemens 3VA1 panel footprints and busbar systems. Depth of 70 mm means it clears most gland plates and backpanel wiring ducts without interference. The 3VA1 series uses screw-clamp terminals; wire range and torque values are on the nameplate. For a panel builder, the 76.2 mm width (3 inches) per pole is the key fill-factor number when laying out a multi-breaker distribution block.