Fan Controllers - How many fans per channel do you run?

[Flash Jordan]

Hi all

I'm currently setting up my first watercooled build, and have got pretty much everything I need ready for me to start (just waiting on a couple of bits on backorder to come back in stock). I just have a query about fan power draw and fan controllers..

I intend to run two 480mm rads in pull, with a view to later go push/pull on both. I will soon have a Lamptron FC5v2 to handle fan speeds with the intention of keeping things nice and quiet. The fans I am using will be Corsair SP120 Quiet Editions.

Now if I am understanding the maths correctly, each channel on the controller being 30w/12v would mean a total of 2.5Amps. The Corsair website has those fans at 0.08A power draw. So I should be able to (very)comfortably have one whole rad's 8 fans on one channel, the other 8 on the next, right?
I only ask as I don't think I've seen a build log, video, or any forum poster say that they have this many on one channel. I assumed it was an issue of power, but is there any other reason I should not be setting my controller up this way?

Thanks in advance!

Jordan

 

[clutchc]

All else being equal, you are correct. But keep in mind there is a current surge for a brief moment at start up of any electric motor, no matter how small. It's called 'locked rotor current'. For just a brief instant, there is a dead short until the motor begins spinning.

 

[Flash Jordan]

All else being equal, you are correct. But keep in mind there is a current surge for a brief moment at start up of any electric motor, no matter how small. It's called 'locked rotor current'. For just a brief instant, there is a dead short until the motor begins spinning.

Thanks for your reply. Is there any way of calculating this locked rotor current, or is it more of a trial and error kind of deal? I'm hoping 4 fans on one 30w channel will be possible, perhaps 8 on one would be pushing it.

 

[clutchc]

On larger motors, it is listed on the nameplate. But tiny DC motors like case fans do have that. Maybe a very accurate VOM meter with peak hold would catch it. If you have one, try it. Set it for the appropriate amp range and insert it in series with the motor. All VOM meters should be good for up to 10Amps or so, far more than that tiny motor will draw.