What it is and what it does
The Siemens 3VA2163-5KP32-0BA0 is a 3-pole SENTRON molded case circuit breaker (MCCB) rated for line protection, with a continuous current of 63 A across the full ambient range from 40 °C through 70 °C — no derating needed as the panel warms up. Breaking capacity hits 121 kA at 415 V and 187 kA at 240 V, so it handles high-fault utility feeds without cascading upstream. At 690 V the rating drops to 3.7 kA — that's the limit for 690 V secondary circuits. An undervoltage release (UVR) is built in — the breaker trips if control voltage drops, which is standard for emergency-stop chains or mains-loss protection on motor feeders.
Panel fit and integration
Mounts on a standard DIN rail. Dimensions: 105 mm wide, 181 mm tall, 86 mm deep (4.13 x 7.13 x 3.39 inches). Rated insulation voltage is 800 V — the MCCB is safe for 690 V line-to-line panels with margin. Power loss maxes at 6.5 W, so thermal rise inside the cabinet is minimal; no forced venting required for a single unit.