What the 250 A and ETU550 mean for fit
Line protection version means it is set up for feeder or main breaker duty, not motor protection. Breaking capacity is the real selector here: 187 kA at 240 V, 121 kA at 415 V and 440 V, 79 kA at 500 V, 5.1 kA at 690 V. At 415 V this handles most industrial distribution fault levels without cascading upstream. Temperature derating is published: full 250 A up to 50 °C, then 238 A at 55 °C, 225 A at 60 °C, 213 A at 65 °C, 200 A at 70 °C. If this breaker lands in a non-ventilated enclosure or next to heat-generating gear, the 55 °C row is the realistic planning number.
Auxiliaries and release configuration
No undervoltage release, no ground fault monitoring, no phase failure detection on this variant. Panel cutout and mounting pattern match the other 3VA2 breakers in this frame size.