What this MCCB is and what the ratings mean for fit
The Siemens 3VA2110-5KP32-0CL0 is a SENTRON molded case circuit breaker (MCCB) for line protection, rated 100 A continuous current (Iu) with an ETU850 electronic trip unit. The 100 A rating holds flat from 40 °C to 50 °C, then derates to 96.25 A at 55 °C, 92.5 A at 60 °C, 88.75 A at 65 °C, and 85 A at 70 °C — so if the panel ambient runs above 50 °C, the breaker's effective capacity drops; size the load accordingly. Its interrupting ratings are substantial: 187 kA at 240 V, 121 kA at 415 V and 440 V, 79 kA at 500 V, and 4.25 kA at 690 V. That 187 kA at 240 V means it can safely clear a fault at that level without upstream devices needing to coordinate — useful on high-capacity transformer secondaries or busway taps where available fault current is high. Three-pole construction, 800 V rated insulation voltage (Ui). The ETU850 electronic trip gives adjustable curves and communication capability — this variant includes a communication function and an undervoltage release (UVR). It also carries 2 auxiliary switches, 1 trip alarm switch, and 1 electrical alarm switch (HQ version), plus a trip indicator. No ground-fault monitoring or phase-failure detection on this unit.
Panel fit and mounting
Dimensions: 105 mm wide, 181 mm high, 86 mm deep. That 105 mm width is the standard 3-pole MCCB footprint for this SENTRON frame size — it fits the same panel cutout and bus-bar spacing as other 3VA2-series 3-pole breakers. The 86 mm depth leaves room behind the door for the rotary handle or motor operator if fitted later. Operating temperature range is -25 °C to 70 °C; storage range -40 °C to 80 °C. Maximum power loss is 12.5 W — negligible for panel thermal budgeting but worth noting if the enclosure is tightly packed and sealed.