What the interrupting ratings mean for your fault duty
The 3VA2025-6KQ32-0AA0: This breaker clears 242 kA at 240 V, 187 kA at 415 V and 440 V, 121 kA at 500 V, and still holds 3 kA at 690 V. Those are the maximum fault currents it can safely interrupt without welding or rupturing — sized for high-available-fault panels, typically close to a transformer or generator bus. At 690 V the 3 kA figure is a derate; if your system runs that voltage with fault currents above 3 kA, step up to a higher-rated frame.
Thermal performance — flat 25 A from 40 to 70 °C
Rated current holds at 25 A across the entire operating temperature band, from 40 °C through 70 °C. No derating curve to calculate — the ETU860 handles it electronically. Ambient at 70 °C is common inside sealed cement-plant or steel-mill enclosures; this breaker eats the dust and runs without a current haircut.
Trip unit and protection features
The ETU860 electronic overcurrent release gives you adjustable N-conductor protection (OFF, 40% to 160% of Iu) and ground-fault monitoring via summation current formation on the L-conductor. Communication function is onboard, so it talks to a higher-level system for metering and trip events. No undervoltage release, no voltage trigger, no trip indicator on this variant — those are separate accessory add-ons.
Physical fit and panel integration
Dimensions are 105 mm wide, 181 mm high, 86 mm deep. That's a standard SENTRON 3VA2 frame footprint — it mounts on a DIN rail or bolts into a panel baseplate. IP40 on the front means it's sealed against solid objects over 1 mm but not against water ingress; keep it inside a cabinet, not in a washdown zone.