The ATV9A0C45Q4: The 450 kW / 764 A normal-duty figure tells you the drive is sized for a 450 kW four-pole induction motor on a pump or fan curve. The 355 kW / 611 A heavy-duty rating is the headroom for constant-torque loads like conveyors or extruders — if your motor plate says 355 kW and your load profile is high-starting-torque, this is the number to match. Switching frequency is adjustable 2.5–8 kHz, but above 2.5 kHz you derate the output current. For a motor run at 4 kHz to quiet the windings, expect to drop to the heavy-duty current curve. STO (safe torque off) is rated SIL 3 per IEC 61508 — that meets the safety integrity level for most machinery directives without an external safety relay. The drive supplies the 24 V DC for STO internally (21–27 V range), so you wire two channels direct to the control terminals.
Integration notes
Cabinet-mount chassis with IP00 protection — you supply the enclosure to meet IP21 or IP54. The integrated EMC filter meets category C3 for 300 m of motor cable, so for a standard industrial panel you skip the external filter on the line side. Three option-card slots (A, B, C) let you add Profibus DP, PROFINET, EtherCAT, DeviceNet, CANopen, or I/O extension modules without replacing the drive.