Brushless fan

I bought a brush-less fan PFB1212UHE for £14. It seemed like a good deal - I was mostly concerned with the air flow and static pressure. It would have been better to buy an AC fan, because I need a 60W 12V power supply to control it. That's going to double the price... At one point I also thought I was going to need a brushless motor controller, but it just runs on 12V, and has an output signal which is one pulse per revolution. I guess that makes variable speed control relatively easy.

It really is a powerful fan! It weights 380g and can levitate a couple of millimetres off the desk.


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