Ventilation systems are responsible for the supply and exchange of air in defined areas. A differentiation is made between ventilation and air-conditioning technology and process air technology. Whereas process air technology is divided into the areas of supply, extraction, filtering and drying, ventilation and air-conditioning technology is divided into the areas of external air plants and circulation systems.

The movement of air (extraction) is undertaken using fans (blowers) that are equipped with electrical drives. The torque-load characteristic of fans increases as a quadratic function of the speed. An increased start-up torque must be considered. If the drives are speed controlled, defined air volumes and pressure ratios can be provided without losses.

Conventional speed-control of fan motors is currently implemented using frequency inverters. At Eaton, the frequency inverters are designated with the series designations M-Max and H-Max.

If a constant fan speed is required during operation – implying a constant volume of air – soft starters are used for controlled soft starting. At Eaton, these device series are designated as DS7, DS6 and DM4. This component can limit both the start-up current as well as the permissible torque. This is particularly important on fans with large blades. Eaton has developed the HVAC drive profile “Kick Start” designed to overcome the increased level of starting torque.