The Siemens SENTRON 3VA2510-5KQ32-0BA0 is a 3-pole molded case circuit breaker rated for 1000 A continuous current at 40 °C, with a breaking capacity of 187 kA at 240 V, 121 kA at 415 V, and 53 kA at 690 V. The ETU860 electronic trip unit gives you adjustable long-time (tr 0.5 to 25 s) and short-time (tsd 0.05 to 0.5 s) delay settings, plus ground fault monitoring via summation current formation on the L-conductor. This is a line protection version — meaning it's configured for feeder and main breaker duty, not motor branch circuit protection. The communication function means it can talk to a higher-level system for monitoring and control, which matters if you're building a switchboard with power management or remote trip indication.
Thermal derating — the real-world current you can actually pull
At 60 °C it drops to 955 A, at 65 °C to 885 A, and at 70 °C to 815 A. The maximum power loss is 123 W, which factors into enclosure ventilation calcs.
Physical fit — panel and enclosure integration
Dimensions: 320 mm height, 210 mm width, 120 mm depth. That's a standard SENTRON 3VA form factor for this current class — mounts on a mounting plate or into a switchboard chassis, not a DIN rail.
Selectivity and coordination — what the trip settings buy you
The ETU860 allows you to set long-time pickup Ir up to 1000 A, with delay tr adjustable from 0.5 to 25 seconds. Short-time pickup and delay (tsd) range from 0.05 to 0.5 seconds. That gives you real selectivity with downstream breakers — you can delay the trip long enough for a branch breaker to clear a fault without taking the main offline. Ground fault monitoring via summation current formation lets you detect leakage without a separate GFCI module, which simplifies wiring in solidly-grounded systems.