What this 800 A MCCB delivers
It carries 800 A continuously at 40 °C ambient and holds that rating through 60 °C, then derates to 767 A at 65 °C and 703 A at 70 °C — useful to know if the breaker lives in a hot enclosure or next to other heat sources. Breaking capacity is 242 kA at 240 V AC, 187 kA at 415 V and 440 V, 121 kA at 500 V, and 74 kA at 690 V. The ETU320 electronic trip unit gives adjustable long-time pickup (Ig) from 17 A minimum and short-time/short-circuit pickup (Ii) adjustable from 1,200 A to 8,000 A. Neutral protection is configurable OFF, 50%, or 100% of the phase setting.
Dimensions are 280 mm wide, 320 mm high, 120 mm deep — a substantial frame that needs a clear panel area and adequate bending radius for 800 A cable or busbar connections. Maximum power dissipation is 231 W at rated current, which factors into enclosure thermal design and ventilation requirements.