What is the RPM of a High Speed Ceiling Fan?
The RPM of a high speed ceiling fan depends on a few factors. Blade size, the number of blades, and the amount of air moved all go into the equation. Therefore, there is no single RPM number for a high speed ceiling fan.
Amount of Air Moved
Typically given as CFM, or cubic feet per minute, this is what most people will actually notice when industrial ceiling fans are running. Of course, they won't stop and mention a particular figure. However, everyone will know whether or not it feels windy. The more CFM a fan moves, the windier it will typically feel. However, if the fan is up high enough, the sensation of breeziness will be diminished.
Number and Size of Fan Blades
The more blades a fan has, the slower it can go while still delivering the same CFM. This is also true of blade size. When a fan has a combination of a large or long blade size and a large number of blades, it can spin very slowly and still move an amazing amount of air. An industrial 60" ceiling fan will often seem to be moving at a low rate of speed, yet can produce quite breezy results at its higher settings.
Variable Speed Operation
Some fans have the option to vary their speeds. This is a great feature since full power doesn't have to be used when it isn't needed. Of course, the RPM of these high speed ceiling fans changes with the setting used.
Why Are They Called High Speed Ceiling Fans if They Often Spin Slowly?
Many people automatically think a fan has to move quickly to blow a large amount of air in a short time. This is a natural assumption, since if a human wants to do a lot of something in a short time, he or she has to speed up. Many home fans are fairly weak at low speeds, too, and this cements the assumption.
Industrial ceiling fans, on the other hand, are engineered to use other methods besides raw speed to get the job done. Their manufacturers typically don't refer to them as "high speed" because even though the fans can go fast, they generally don't have to except in extreme circumstances. Instead, the fans use bigger blades and more of them to be able to transfer a lot of air quickly.
Of course, speeding up these big fans moves even more air, but in an industrial situation, it is generally better to get a bigger fan instead of a faster one. This is more efficient, and therefore, costs less to run. It is also easier on the motor, so the fan will last longer.
It is also important to note that in some cases, the goal is to move a lot of air down from the ceiling without making it feel windy. This gets trapped heat back down to where the people are, thereby reducing the need to run a furnace. In this case, the best speed will get the job done quickly, but without producing a cooling wind in the process.
Shop Industrial Fans Direct for a wide selection of ceiling fans, for industrial and commercial applications.