The 400F series DC Axial Fan is suitable for high air performance with moderate pressure build-up. The flow of air through the fan blades is parallel to the rotation axis. They are extremely flat and space-saving integrated motor. Every single type of fan can be optimally integrated in the respective device concept. The highly economical brushless motor technology of these fans provides unique variety of intelligent innovations. The DC fans have electronically commutated drives with electronic protection against reverse polarity. The DC fans with sleeve and ball bearings are powered by class E insulated motors. They can be operated on voltages that are up to 50% lower and 25% higher than their nominal voltage. This enables the air performance to be adapted to the cooling requirements and allows the noise to be reduced, even if the fan does not have a control input. Closed-loop speed control and function monitoring are becoming increasingly important in many applications.