Flying leads improve air flow in compact fans

Motors with flying leads can be an excellent solution for axial fans and other applications where space is limited. Not only is it easier to connect the motor, it also improves air flow and has a more compact design.


Hoyer now provides motors with flying leads, which means more flexibility when it comes to connections and the design of applications.

A motor with flying leads has wires that protrude from the motor housing itself, rather than being connected via a terminal box mounted on the motor. This makes it easier to fit the motor if space is limited.

Perfect for axial fans

This applies to an axial fan, for instance, whose motor and fan are inside a tube. It can be difficult for installation technicians and service personnel to reach the electrical components. This is when it is very beneficial to use a motor with flying leads that can be connected to a terminal box attached to the outside of the unit itself.

“Not only is an axial fan with a motor with flying leads easier to connect to, it also delivers improved performance and airflow because there is no large, square terminal box in the way of airflow. It also means you can have a more compact design,” says Adam Slupinski, Segment Manager, HVAC, Hoyer.

“Depending on the aerodynamic design, primarily of the impeller, significantly better performance can be achieved. We’ve seen examples where fan manufacturers have improved the efficiency of their fans by 5–10 percent by using flying leads.”

For ATEX and maritime use as well

Hoyer primarily supplies motors with flying leads for customised solutions with several different industries, such as ventilation for tunnels, mining operations, and ships, as well as well as fans for snow guns.

Hoyer supplies motors with flying leads for all standard type approvals and modifications, for example low and high temperatures, ingress protection class IP66 and ATEX zones 1 and 2.

This means that the motor and the fan can be configured to meet a wide range of different needs, including:

Motor sizes: from IEC 80 – IEC 315 (and up to IEC 355 in the near future)

Ingress protection class: up to IP66 – can also be carried out in accordance with II 3D Ex tc IIIB T120/II 3G Ex ec IIC T3

Cables: standard halogen-free cables and marine-approved cables for temperature resistance up to 90 degrees Celsius