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No. 3488 Rama 9 Rd.,
Suanluang, Bangkok
10250, Thailand
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A Big Bold Step Forward

Big Fan Series: BDC
A Leap in continuous high-torque direct drive motors
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The Best of Both Worlds

Our DC Fan Series draws from the best of two worlds. USA technological expertise on electrical torque machines and Asia’s economical production of aero-mechanical components. The result is a product that is high in both reliability and affordability.
Electric Torque Machines (ETM) of Arizona, USA designs and manufactures highly efficient continuous torque motors optimized for direct drive applications. ETM’s F-series DC Motor System is the only proven make known for its reliability in HVLS fan applications.
Features of ETM BLDC Motor
Increased efficiency and reliability
Exceptional torque per size, weight, and cost
Small, gearless system enables silent and elegant fan design
Read More About BLDC Motors
Customer Load Center (CLC) Human Machine Interface (HMI) Electronic Driver DC Motor

A Technological Marvel in Fan Assembly Design

The precision-milled fan hub and fan strut pieces ensure a flawlessly fitted connection that prevents excessive fan blade movement. A uniquely designed concave-convex joint between the fan hub and fan strut also boosts security while a vibration dampening material is used to eliminate stress on the fan hub.

The result is a very strong and heavy duty blade-to-hub connection that makes the fan blade impossible to depart from the fan assembly.
Fan Strut Fan Hub Fan Blade Bolt & Nut Concave/Convex Joint Vibration Dampening Bushing

Unique Blade Design

The tapered, twisted & tilted design of the fan blade compensates for the substantial velocity differences that stretch from one end of the blade to the other. It ensures the blades produce the same amount of airflow across the entire length of the blade. (See below diagram).

Contrast this to the commonly found extruded blade designs of other makes where the blade contour is uniform along the length of the blade, the area directly beneath the center of the fan will have much lower air velocity. This causes an empty air ‘hole’ effect below the fan. (See below diagram)
Tapered & Twisted Blade Uniform Blade Design
Compensates for the substantial velocity differences that stretch from one end of the blade to the other. As a result, air flow is even throughout the entire area covered.
Uniform ContourBlade Design
When blade contour is uniform along the length of the blade as in the case of aluminum extrusion design, an area directly below the fan has no airflow being felt.

Fan Safety Features

FAN STABILIZATION WIRES
4 Guy wires are installed to keep the fan stable without excessive oscillation during operation.
ANTI-DROP STEEL CABLE
In the unlikely event that the fan blade is dislodged, it will be secured to the fan assembly by this Anti-drop steel cable.
SAFETY LOOP-OVER WIRES
2 thick multi-strand steel wire is used to loop the entire fan over the roofing structure to prevent it from being dislodged.

DC Motor Fan Series BDC

Lighter Weight
Maintenance Free

Specification & Performance

Fan Diameter 7.3m & 3.1m

Model
BDC - 7.3
BDC - 3.1
BAC - 3.1
7.3 m
3.1 m
Blade Type
2 ply alu 5052, 2.5 mm thick
1 ply alu 5052, 1.5 mm thick
Maximum Speed
100 rpm
45 rpm
Air Flow
780,000 m³/h
203,800 m³/h
Air Covered Area
1,400 m²
280 m²
Noise Level
40 dB (A)
35 dB (A)
Drive & Motor System
F170
F13
Power Supply
50 Hz, 3Phase, 380 V
50 Hz, 1Phase, 220 V
Operation Control
HMI
HMI
Total Weight
80 kg
30 kg
Features of BLDC Motor
Increased efficiency and reliability
Exceptional torque per size, weight, and cost
Small, gearless system enables silent and
elegant fan design
Model
BDC - 7.3
BDC - 3.1
Drive & Motor System
F170
F13
Max Cont. Torque (Nm)
175
14
Max Cont. Power (W)
1,100
175
Input Power
50 Hz, 3Phase, 380 V
50 Hz, 1Phase, 220 V

7.3m Fan Zone Performance

Zone
Avg. Velocity
∆TPTD
A
3.0 - 3.5 m/s
4 - 5 °C
B
2.0 - 2.5 m/s
3 - 4 °C
C
0.5 - 1.0 m/s
2 - 3 °C
∆TPTD = Perceived Temperature Drop @ 8m Fan Height
A B C 14 m 28 m 40 m

3.1m Fan Zone Performance

Zone
Avg. Velocity
∆TPTD
A
2.0 - 2.5 m/s
3 - 4 °C
B
1.0 - 2.0 m/s
3 - 3.5 °C
C
0.5 - 1.0 m/s
2 - 3 °C
∆TPTD = Perceived Temperature Drop @ 6m Fan Height
A B C 7 m 12 m 18 m

Make It Your Own

Color your blades to match your environment. Our unique blades can be painted to provide you with an aesthetically pleasing fan unit.
Pick Your Color

Contact Us

Feel free to drop us any questions you have, or schedule a visit to see the Big Fan in person!

Come Visit Us for a Product Demo

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