Axair Fans has established long term partnerships with manufacturers ECOFIT s.a. (France) and ROSENBERG Gmbh (Germany) and are able to offer Energy Efficient EC fans and air movement products. Both Ecofit & Rosenberg develop and manufacture their own motors and fans. The Ecofit EC range use motors from 65 up to 113Wa, the Rosenberg range use motors from 1.1 up to 3.4Kwa motors.
EC Technology stands for Electronically Commutated and combines AC and DC voltages, which is essentially a fan with a brushless DC motor, bringing the best of both technologies. The EC motor is running on a DC voltage but with a single phase 230 Volts AC supply (115 Volts option). The effect is minimum power consumption, infinite control possibilities (through 0-10V signal or PWM), but with a standard 230 volts 50/60Hz supply. Unlike the DC motor, which requires a separate controller (often considered as expensive, cumbersome and impractical), EC technology incorporates voltage transformation within the motor. The non-rotating part of the motor (stator) has been extended to make room for an electronic PCB board which includes power transformation AC to DC, as well as the controls. The whole aspect is similar to a standard AC external rotor motor but with a slightly deeper base.
The results are reduced energy consumption producing an increased efficiency of 70% on current models (compared with 50% maximum in the AC single phase direct alternative). The electronically commutated motor can be offered with a number of options, such as Hall effect sensor or alarm output. The EC programming is also suitable for constant speed or constant pressure control.
DC motors already have low power consumption but if used in an AC application, the power needed to convert AC to DC, requires a bulky, inefficient transformer. The EC motor incorporates voltage transformation within the motor. The non-rotating part of the motor (stator) is extended to make room for an electronic PCB board which includes power transformation AC to DC, as well as the controls.
All the features of the external rotor motor are kept, including compact assembly, easy speed controllability, efficiency and characteristics.
With an EC motor the electronic circuitry stands in lieu of the traditional mechanical commutation meaning the right amount is being supplied in the right direction at exactly the right time providing precise motor control.
EC technology motors have a near flat efficiency curve which barely varies across the speed range. A range of which is not limited by synchronous speeds or susceptible to voltage variations like its AC counterpart. Its AC equivalent will operate at a precise point on the curve which equates to its maximum efficiency, either side of this point and the efficiency diminishes.
Typical AC motors have losses in terms of power consumption (copper + iron losses), slippage and frictional losses (mechanical power). EC motor have no slippage losses, reducing losses and increasing efficiency.
By comparing 2 backward curved centrifugal impellers, one in AC and the other in EC.
The Rosenberg EC motor (EC = electronically commutated) is an inverter-fed synchronous motor with permanent magnets in an external rotor design. The AC mains voltage is rectified by the commutation electronics of the EC motor. A downstream inverter provides the motor with the motor voltage depending on the load, similar to the principle of a frequency inverter. In conjunction , all parameters of the commutation electronics and are optimally matched to each other. The intelligent EC commutation electronics decide how the motor windings in the stator are supplied with current (commutation) depending on the position of the motor, direction of rotation and speed set point. Permanent magnets generate the magnetic counterfield in the rotor, the torque required for rotation is generated from the interaction of the stator and rotor fields. A mounting flange on the rotor is used for stable impeller mounting. The simple and quick electrical connection is made either via a terminal box with cable glands or a connection cable, depending on the motor series. The use of deep-groove ball bearings closed on both sides with specially matched grease ensures maintenance-free and low-noise operation. The winding insulation meets thermal class F. Through the use of intelligent electronics, a wide variety of control and regulating functions can be taken by the EC motor depending on the area of application (infinitely variable speed control, pressure control, volume flow control, temperature control, air quality control).
✔️ High Efficiency
✔️ Low power consumption
✔️ Integrated monitoring function (motor temperature, locked rotor and many more)
✔️ Simple connection (Plug & Play)
✔️ Expanded functionality (pressure control a.s.o.)
✔️ Compact design
|Model||Fan/motor type||Supply||Motor power||Speed|
|DKHR 315-2SW-098||AC 3 phase fan 2 pole motor||400Volts 50Hz||1.52Kwa||2750rpm|
|GKHR 315-CIW.098||EC 3phase fan||380/480Volts 50/60Hz||1.41Kwa||2950rpm|
|Model||Point 1 - 2603m³/h at 900 Pa||Point 2 - 2000mm³/h at 166Pa||Point 3 - 3300mm³/h at 450Pa|
|DKHR 315-2SW.098.6FA (Fan power)||Power : 1.42kW||Power : 0.62 kW||Power : 1.41 kW|
|Efficiency : 37.5%||Efficiency : 14%||Efficiency : 28%|
|GKHR 315-CIW.098.5FA (Total power)||Power : 1.33 kW||Power : 0.27 kW||Power : 1.04 kW|
|Efficiency : 49.6%||Efficiency : 38%||Efficiency : 45%|
Let’s assume a laminar flow workstation requiring 13200m³/h at 450Pa. This requires 4 off Ø315 backward curved fans. Now let us assume that this workstation operates for 50 weeks of the year and for 8 hours per day at full speed. During non working hours to maintain the work area, the fans are run at roughly half the airflow.
Let’s compare the power consumed :
|AC fan||2800hrs @ 4 x 1.41kW = 5.64kW||15,792 kWh|
|5600hrs @ 4 x 0.62kW = 2.48kW||13,888 kWh|
|Total A||29,680 kWh|
|EC fan||2800 hrs @ 4 x 1.04kW = 4.16kW||11,648 kWh|
|5600 hrs @ 4 x 0.27kW = 1.08kW||6,048 kWh|
|Total B||17,696 kWh|
|A minus B||11,984kWh saved with the EC fan|