The VW3A99ACA03 is a steel air duct from the Altivar Process Modular range — an installation accessory for single-drive architecture. It's the outlet power cooling air duct for one standard power module, designed to integrate the drive into a single IP54 cabinet.
What it does in the cabinet
This steel duct directs the hot exhaust air from the power module out of the enclosure. Without it, heat recirculates inside the cabinet, derating the drive or tripping thermal protection. It's a single-drive architecture part — one duct per power module. If you're building a multi-drive cabinet with shared bus, this isn't the piece you need.