What this MCCB is and what it does
The Siemens 3VA2163-5MN32-0BL0 is a SENTRON molded case circuit breaker (MCCB) configured for motor protection. Rated continuous current Iu is 63 A, and the rated insulation voltage Ui is 800 V. Breaking capacity is the headline here: 187 kA at 240 V AC, 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 17 kA at 690 V. Those figures mean this MCCB can safely interrupt a bolted fault up to 187 kA at the lower voltage level — critical for high-fault installations like transformer secondaries or large motor control centers where available fault current exceeds typical 25 kA or 65 kA breakers.
Ratings and what they mean for your panel
The 63 A rating holds flat from 40 °C through 50 °C — no derating needed in a warm enclosure at those temperatures. At 55 °C it derates to 60.48 A, at 60 °C to 59.22 A, at 65 °C to 57.96 A, and at 70 °C to 56.7 A. If your panel ambient runs above 50 °C, you need to account for that 4–6 A drop at the top end. Physical fit: 105 mm wide, 181 mm tall, 86 mm deep. That width is standard for a 3-pole 63 A MCCB frame. Maximum power loss is 75 W. That's the heat the breaker dissipates at full rated current — factor it into your enclosure thermal calculation if you're stacking multiple MCCBs in a confined cabinet. Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. The storage limit governs handling and warehousing, not running conditions.
Motor protection specifics and auxiliary options
This variant is explicitly a motor protection version, equipped with phase failure detection and an undervoltage release (UVR) as the auxiliary release type. The UVR trips the breaker when supply voltage drops below a threshold — standard for preventing automatic restart after a brownout on motor circuits. Auxiliary contact configuration is 2 auxiliary switches + 1 trip alarm switch + 1 electrical alarm switch HQ. That gives you two N.O./N.C. signal contacts for status feedback, plus dedicated alarm contacts for trip indication — enough for remote monitoring without an external interface module. The integrated auxiliary trip is order code 3VA9608-0BB11, and the supplied basic switch is 3VA2163-5MN32-0AA0. Those are the internal subcomponents — useful if you're ordering spare parts for the assembly.