630 A MCCB with ETU850 — what the ratings mean for the panel
The Siemens 3VA2463-5KP32-0AG0 is a 3-pole SENTRON molded case circuit breaker (MCCB) rated for 630 A continuous current Iu, with an ETU850 electronic trip unit that provides adjustable long-time, short-time, instantaneous, and ground-fault protection curves. This is the line-protection version — no undervoltage release, no voltage trigger, no phase-failure detection built in — so it is sized for main feeder or large subfeed duty where the trip unit handles the coordination, not auxiliary relays. The interrupting ratings are the headline: 187 kA at 240 V, 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 17 kA at 690 V. That 187 kA figure at 240 V means this breaker can safely clear a fault on a high-capacity 240 V transformer secondary without the arc re-striking or the case rupturing — it is sized for high-fault-current service entrances, not just branch panels. Temperature derating is published across the full operating range: 630 A at 40 °C ambient, stepping down to 450 A at 70 °C. If this breaker lands in a hot switchroom or a non-climate-controlled enclosure, the 70 °C figure (450 A) is the one that governs the load it can actually carry — not the 630 A nameplate. Maximum power loss is 162 W, which matters for enclosure thermal management.
Communication and auxiliary contact configuration
This MCCB includes a communication function, which on the 3VA platform typically means it can interface with a fieldbus or Ethernet gateway for power monitoring and remote trip indication — useful for a plant-wide energy management system or a PLC-driven shutdown sequence. The auxiliary contact version is specified as 1 auxiliary switch + 1 trip alarm switch HP, giving one N.O./N.C. set for status and a separate alarm contact that changes state only on a trip event, not on manual open. The basic switch (the breaker mechanism without the trip unit) is order code 3VA2463-5KP32-0AA0, and the integrated auxiliary trip is 3VA9608-0BB11 — these are the spare-part codes if the ETU850 or the auxiliary switch needs replacement separately.
Where this MCCB fits in the system
A 630 A MCCB with 187 kA interrupting capacity and electronic trip is typically the main breaker in a 240 V or 415 V distribution panel feeding downstream subpanels, motor control centers, or large single loads (chillers, compressors, large pumps). The ETU850 supports adjustable long-time pickup and delay, short-time pickup and delay, instantaneous pickup, and ground-fault — so it can be coordinated with downstream breakers and fused switches. The 800 V rated insulation voltage (Ui) covers 690 V systems with margin. Operating temperature range is -25 °C to +70 °C, storage from -40 °C to +80 °C. The 162 W maximum power loss at full load means the enclosure must be sized to dissipate that heat — a standard steel enclosure without forced ventilation will rise above the 40 °C ambient that the full 630 A rating assumes.