AC, DC, and EC motors, not to be confused with AC and DC current, or a certain Australian rock band, are arguably the most important part of a fan. At the end of the day they all do the same thing – making a fan spin, but each type of motor does it slightly differently to the others. So, what’s the difference between AC, DC and EC motors? AC motors (alternating current) AC motors use a permanent magnet on the outside, with an electromagnet in the middle (attached to the shaft) and carbon brushes for power to create rotational force. These motors have been around for years, and are typically cheap and simple. They get the job done. The main downside is their limited speed control options, and higher energy usage, and louder operation due to friction from the brushes. Brushless DC motors (direct current) To put it simply, brushless DC motors are an inverse of AC motors. They use a permanent magnet on the inside, with a set of electromagnets on the outside to create rotational energy. These electromagnets require an additional controller and transformer outside of the main motor unit to function. These motors tend to be significantly more energy efficient (~30% on average), durable, and quieter than their AC counterparts, lending themselves nicely to continuous applications. Brushless DC motors also typically offer finer control over the fans speed. However, they are often more expensive due to the additional components and complexity. Note – the controller and transformer are typically built into the fan, so no additional steps are needed to make it function. EC motors (electronically commutated) EC motors are a slight improvement on their DC counterparts. They function very similarly, with a permanent magnet on the inside and a set of electromagnets on the outside, but they have a controller directly integrated into the motor. Having an integrated controller means more space within the fan chassis can be devoted to the motor, leading to small efficiency increases. Just like brushless DC motors, EC motors are significantly more energy efficient (~30%) compared to AC motors, and are note EC motors have similar downsides to brushless DC. Smaller and more complex components mean the fan is more expensive. What’s the difference between Brushless DC and EC motors? Practically speaking, they are the same thing. Technically speaking, it’s all about the location of the motors ‘brain’ and transformer. It is either inside the motor (EC), or outside the motor (DC). Neither require additional work to install, as the componentry is still all stored within the fan’s housing. What does this mean for you when choosing a fan? The simple answer is that you can use EC and brushless DC interchangeably. If your customer wants a quiet, energy efficient option, any brushless (EC or DC) fan will meet their needs. For our full range of energy efficient, brushless fans, check out our page here: https://simx.co.nz/categories/extraction/continuous-extract-ventilation