Type A detection means it catches sinusoidal AC faults plus pulsating DC fault currents — common in modern loads with rectifiers and switching power supplies, like variable-speed drives, washing machines, or LED lighting. The 30 mA trip threshold covers personnel protection (hand-to-hand or hand-to-ground contact) under IEC 61008-1.
Rating so-what and derating
Above that, the part derates linearly: 77.57 A at 45 °C, 74.59 A at 50 °C, 70.22 A at 55 °C, 64.47 A at 60 °C, 57.35 A at 65 °C, and 48.8 A at 70 °C. Short-circuit current rating is 10 kA per IEC 61008-1, with a let-through current of 7,100 A and a permissible I²t of 110,000 A²·s. Surge current resistance is rated at 1 kA (8/20 µs waveform), so it handles lightning-induced or switching surges common in industrial environments without nuisance tripping.
Depth is 70 mm, height 90 mm, width 72 mm (4 MW). Silicon-free construction, so it's safe for use in painting or coating lines where silicone contamination could cause fisheyes or adhesion failure.