The Helios TSD 7.0 is a voltage reduction speed controller designed for managing the operation of one or multiple 3‑phase fans. It features selectable output voltages of 0, 80, 140, 280, and 400 volts, allowing for precise fan speed regulation. The unit is enclosed in a durable IP54-rated housing that provides protection against dust and water spray. Operating at 50/60 Hz, this controller ensures reliable and flexible fan speed adjustment in various ventilation setups.