Reading the duty stack: which number actually switches the motor
The ACS800-104-0440-7: Three ratings sit on the nameplate and each is a different question. Heavy-duty use is I_hd 286 A at P_hd 270 kW — the figure you size a constant-torque, high-inertia, or high-break load against. Light-overload use is I_N 367 A at P_N 355 kW — the variable-torque / light-overload profile. No-overload use is P_cont.max 355 kW with I_cont.max 382 A, and the peak the drive will hand you for short transients is I_max 571 A. Pick the curve by the load, not by the largest kilowatt figure on the page. Heat dissipation of 7 kW at full load is the dimensioning figure the panel OEM sizes the cabinet AC and the exhaust path on. Treat it as a heat source of that magnitude, not as a footnote — R8i is the frame where cooling design decides whether the drive derates in a hot enclosure.