The ETU320 electronic trip unit gives you adjustable long-time pickup (Ir) from 320 A to 800 A and short-time pickup (Ii) from 1200 A to 8000 A, with response times tr adjustable 0.5 to 17 s. That range lets you coordinate selectivity with downstream breakers without oversizing the main. Breaking capacity is 187 kA at 240 V, 121 kA at 415 V, and 53 kA at 690 V — figures that put it in the high-interrupting category for industrial mains. At 415 V it clears a 121 kA fault without external fuses, which covers most LV switchgear secondary-side faults.
Thermal performance and derating
That's a wide flat curve — you don't lose headroom in a warm enclosure until you push past 65 °C.
Dimensions are 210 mm wide, 320 mm high, 120 mm deep — a standard SENTRON 3VA2 frame size.