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Does anyone know of a small size DC fan?

Does anyone know of a small size DC fan?

Does anyone know of a small size DC fan?

It needs to fit in a 1U rack space (1.75"). I have found one at 1.57" square but it is still a touch big. Obviously I am looking for the best CFM available.


RE: Does anyone know of a small size DC fan?

The fan you have founf is a 40 x 40. They are usually measured in mm. They make them as small as 25 x 25 (.984").
But the CFm is only around 1.9 to 2. Ive used them before Poewer supplies.
I have also but in 2 40 x 40 in a 1U box, but had to due some stuff with the sheet metal to fit the fans in it (clearance cuts ahd to be put in to the sheet metal).

You could look at Rodaletech.com

Hope this helps,

RE: Does anyone know of a small size DC fan?

In case you have a doubt on 1.57" fans, I can assure you that they are used in 1U inclosures normally (1U = 1.75"). You have to give it another try once you need better CFM.

RE: Does anyone know of a small size DC fan?

Alpharam is correct.  40mm fans are the most popular fans in 1U enclosures.  If you don't care about noise, a 40x40x28mm fan at 10,000 rpm has a max flow over 15CFM, max pressure over 0.5".  Of course, you can also put multiple fans in series or parallel to boost performance.

There are also 25, 30, and 35mm fans but performance drops significantly.

There are many good sources.  Try NMB, Delta, EBM, or Nidec.

Good luck


RE: Does anyone know of a small size DC fan?

40x40 fans should fit 1U with room to spare. (1.75 front panel - 1.645 Chassis height)

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