Fan Controllers /Watts per Channel

[Zarathustra[H]]

Hey all,

Quick question.

Fan controllers typically have a rated number of watts per channel.

What happens if you plug a fan in that exceeds that wattage?

Does it just spin up to the max RPM it can handle at the specified wattage (good) or does something bad happen (fuses blown, fire, smoke, death, destruction, etc.)?

 

[FnordMan]

Usually the latter, there's reasons that the controller is only rated like that as that's all the equipment can handle. The fan on the other hand won't care and will still try and draw full power which leads to a bad end.

 

[Zarathustra[H]]

Usually the latter, there's reasons that the controller is only rated like that as that's all the equipment can handle. The fan on the other hand won't care and will still try and draw full power which leads to a bad end.

Hmm.

That is too bad.

I am trying to come up with a method to control the fans in a used HP DL180 G6 server I just picked up used on eBay.

The HP engineers were over-cautious when they designed it (probably a good thing for its original datacenter application) using a "sea of sensors" to measure everything in the box and adjust the fans accordingly via PWM. Problem is when you insert a PCIe card it doesn't recognize, it errs on the side of caution cause it doesn't know how hot it is, and sets all fans to max speed, and these are 60mm Sunon fans maxing out at 16k rpm and producing a lot of noise. Enough so that even when it's in my basement it would be too loud.

My plan was to use one of those temperature sensor based PC fan controllers (like the NZXT Sentry range) to monitor temps and adjust fans accordingly, problem is they max out at ~10W and these fans are 18W fans.

The Gelid SpeedTouch6 actually allows for 30W per channel, but it for some crazy reason has a predetermined non-configurable target temperature, allowing for less flexibility.

I wonder what would happen if I were to combine the voltage outputs from two channels on something like an NZXT Sentry 2 and put the two corresponding temp sensors together. Would that result in ~20W per channel, or would it cause some sort of malfunction?

Any other recommendations? Essentially looking any way to automatically control these beasts based on temperature, so I don't have to hear the server in the basement from my bedroom two floors up, and don't need hearing protection when in the basement!

Appreciate any suggestions!

 

[Zarathustra[H]]

It would be easier if there were some sort of temperature probe fan controller with all 4pin headers rather than relying on voltage modulation. Then I could just pull the PWM signal from the fan controller, and wire the 12v and ground direclty to a molex connector coming from the PSU, but I ahve not been able to find a controller like this.

They all seem to rely on voltage modulation. I have one ONE model with PWM, it is a Zalman 3.5" model, but it only has 1 PWM port and 3 3pin ports. I'd get 4 of them, but they are like $70 each...

I read somewhere else that someone said you could somehow wire in a transistor so it relies on the signal from the controller for voltage, but pulls all the amps from the PSU over a molex connector, but I am not THAT electrically inclined and have not been able to find any more details on this.

 

[Zarathustra[H]]

I mean, I could just replace the fans with 4 60mm deltas which use much less wattage, but I ahven't been able to find their static pressure specification anywhere, and I am concerned it's not up to par with the Sunon's.

 

[Tsumi]

I would not combine outputs. That can lead to problems if they're not operating at the exact same voltage.

I believe the Lamptron FC Touch has configurable temperature thresholds, and is 30 watts per channel. The problem with it is that it is full throttle until the temperature drops below the threshold, then it idles.

Why not look into making your own PWM controller using Arduino units?

 

[Zarathustra[H]]

I would not combine outputs. That can lead to problems if they're not operating at the exact same voltage.

I believe the Lamptron FC Touch has configurable temperature thresholds, and is 30 watts per channel. The problem with it is that it is full throttle until the temperature drops below the threshold, then it idles.

Why not look into making your own PWM controller using Arduino units?

That sounds like it would be an awesome solution, apart from the fact that I have a very limited understanding of what an arduino unit is, and very very limited programming knowledge.

I understand its some sort of PLC, correct? I have no idea what would be involved in hooking it up to temperature sensors and sending out a PWM signal

edit:

Just looked up arduino on Wikipedia. Look like cool little devices, but I would be learning C from scratch in order to program it...

 

[Tsumi]

It's simpler than C, they have a bunch of small tutorials to get you started. The most relevant tutorials for you would be analog read and analog write. Analog read would read your temperature probes, and analog write would basically be your PWM output.

 

[Zarathustra[H]]

It's simpler than C, they have a bunch of small tutorials to get you started. The most relevant tutorials for you would be analog read and analog write. Analog read would read your temperature probes, and analog write would basically be your PWM output.

Sounds like this would be the ideal solution long term, but it looks like I have some learning and reading to do.

I'm going to try for an interim solution first.