The heavy-duty rating (PhD 75 kW, IhD 84 A) covers higher peak demands or variable-torque loads such as centrifugal fans or pumps, where the drive must handle a 20% overload for 60 seconds. The light-overload rating (PlD 90 kW, IlD 93 A) sits between the two, suited for applications with infrequent overloads. For a given motor, match the duty class to the load profile — a 90 kW fan can run on the normal-duty rating, but a 75 kW extruder screw requires the heavy-duty headroom.
Physical Integration and Environment
The drive is wall-mounted, frame size R7, with an IP21 enclosure and NEMA Type 1 rating. The wall-mount form factor saves floor space but requires clearance around the heatsink for airflow; plan for at least 200 mm above and below the drive for proper convection cooling.