Why do ceiling fans go from high to low? Why not start from the lowest speed setting and move up to the highest one?
If you own a fan or have ever operated one, you have noticed that it starts with the highest speed setting after being switched on.
There are many theories about why fans go from OFF to the HIGH-speed setting.
They include the operation of the fan, which requires that it start from the highest speed setting simply as a matter of convenience.
Below, we will look at why fans go from Off to High and then lower speeds. We will also examine whether it is practical and whether there are different modes of operation.
Why is the high setting first on fans?
Here are various reasons why most fans go from off to the highest speed setting:
1. Some fans might not start on a low-speed setting
One of the major theories behind the speed settings of fans is the high current required for the motor start.
In some types, especially those with heavy blades, the low-speed setting will not supply enough current to start spinning the motor, causing it to stall.
Therefore, starting with the high-speed setting is practical, which provides a higher current draw.
Once the motor starts, the current required to keep it spinning reduces, meaning that you can lower the speeds without causing a stall.
2. Low resistance in low-speed settings can fry the fan
Another theory for fans going from off to high is the resistance in the motor. There is very little resistance when a ceiling fan is in the rest mode (OFF).
Once the motor starts moving, it produces a back EMF, creating resistance. The higher the speed, the more the back EMF, hence the higher the resistance.
As you already know, motors start with a high current to overcome the stationary position. However, the current spike can fry a fan due to the low resistance.
You have the highest speed setting after OFF guarantees a high resistance, which prevents the components from frying.
3. It is more convenient to go from OFF to High
The other theory explaining why fans go from OFF then HIGH to LOW has to do with convenience. Firstly, the motor experiences a high surge in current immediately after starting.
Therefore, it is more logical to utilize the current by positioning the highest speed setting first.
Secondly, most people only use the highest speed settings, especially in hot areas. Therefore, it is much simpler to go directly from OFF to HIGH when starting and then HIGH to OFF when switching off.
Should ceiling fans be started on high?
There are several theories about why fans start on HIGH, and they all have their merits. However, most of these theories are based on the operation of older fan models, and things have changed drastically over the years.
Today, there are fans with lighter blades that don’t require much current to overcome the load required to start.
Modern circuits can also overcome the resistance issue. The components are much harder to fry.
As for design convenience, some fans use remotes or buttons. They can start on any speed setting. Therefore, while most fans start on the high setting, it is not a must that they do.
Fans going from OFF to HIGH then lower speed setting is common. There are several good reasons why manufacturers have been doing this.
But, with the current technologies, this seems like simply a design practice that caught on. However, the practice might be no longer useful for fans that can not start on any speed setting.