EC Fans for Ventilation

What is a fan and how does it work?

A fan is a set composed of a motor and blades whose main function is to displace a gas (usually air) from one place to another.

Which are the main types of fans?

Helicoidal/axial fans

We call them axial fans when the air flow that they generate passes in a parallel direction to its axis. Axial fans can move large volumes of air with very little pressure.

Radial/centrifugal fans

They are called centrifugal fans when their air flow is driven out radially to its axis. We can differentiate them into two major groups:

Centrifugal fans with forward curved impellers

Centrifugal fans with backward curved impellers

Cross-flow fans

In a cross-flow fan the air flow emerges in a tangential direction to its axis.

Applications

The fans are mostly used in the sectors of air conditioning, ventilation and heating (HVAC). Their main functions are to renew the indoor air replacing stale air with fresh air or increase air circulation for ventilation or cooling.

Our main applications are:

• Air conditioning
• Ventilation
• Extraction
• Heating
• Air curtains
• Refrigeration
• Wind turbines
• Clean rooms
• Compressed air treatment
• Electrical machines
• Electrical cabinets

EC stands for Electronically Commutated, and it combines AC and DC voltages bringing the best of both worlds.

The motor runs on a DC voltage, but with a single phase 230VAC or three phase 400VAC supply. The motor incorporates voltage transformation within the motor.

The non-rotating part of the motor (stator) is extended to make room for an electronic PCBoard which includes power transformation AC to DC, as well as the controls.

An EC motor (Electronically Commutated) is a brushless, direct current, external rotor type of motor. In commutation electronics, an AC voltage is changed into a direct voltage by a commutator.

The motor position is dependent upon voltage supplied via an inverter module (similar to the principle of a frequency inverter).

The EC commutation electronics are different from a frequency inverter in that they decide how the motor phases in the stator are supplied with current (commutation) depending on position, rotation direction and default.

Permanent magnets in the rotor produce a magnetic field which is required for full load production. A high efficiency, low noise, and continuous motor speed control is possible with this. An assembly flange on the rotor is used for impeller assembly. Depending on the motor type, a terminal box is available with cable screw connections or connection cable for easy and quick connection. Depending on the application area is possible to adopt further control functions (e.g. constant pressure control, volume flow control, temperature control).

Conventional DC motors have a housing which contains all the assembly groups like carbon brushes, the collector, bearing, armature with winding, etc. They are arranged one after another. With the EC motor assembly, more space is saved and a collector and carbon brush are not necessary. Therefore the motor is significantly shorter and consequently has advantages with regard to dimensions when installing and quiet operation.

The slightly higher investment costs for EC fans in comparison with conventional motors are mostly amortized within the shortest operation time because of the low energy consumption and lower installation costs (no transformer control, frequency inverter, or phased angle control is necessary).

Fascinatingly efficient. EC technology preserves the environment and reduces costs at the same time.

Advantages of EC technology

• Very high degree of efficiency
• Integrated controller (continuous control)
• Very simple connection
• Additional functions (pressure control, airflow, speed, temperature, air quality, etc.)
• Smaller-sized motor for the same level of performance
• Less power consumption

Videos comparing AC Fans vs EC Fans