What is the Space Allowed for Installing the Fan?
You should think about the space for the fan as early as possible. It is widely accepted that most of the electric and electronic systems will be getting hotter and hotter. That is to say that the role of cooling is becoming more important. Do not do your industrial, structural and functional design without considering the need of cooling at the same time. The smaller the space allowed, the higher the speed of the fan may be needed, and therefore, more noise.
How to Specify a Fan in Terms of its Dimensions
The most common practice when specifying a fan in terms of its dimension is to identify the width (length) and height of the housing. For a fan of square or round shape, you can use its width (square) or diameter (round) along with its height to communicate. For example, a square fan of 60mm x 60mm with a height of 25mm can be named as “sixty by twenty five”. However, if the shape of the fan housing is not square for some reason, the only thing we can do is to specify all the dimensions.