SOLVED Delta fan pulsing

[Yevans]

Hi all,

I am hoping that some of you may be able to help with a little quandry of mine. I currently have two delta fans as I am looking to put them on my H80 to see how low I can get my temps to fall, regardless of the deafening sound.

However, I have an AFC1212DE which works perfectly fine when attached to my NZXT Sentry controller, but my FFB1212EH does not. This instead constantly cycles through off and on as if the voltage is being regulated in a strange way before it reaches the fan itself, but all other fans work fine. I have them both attached to 3 pin headers so I can't see what the problem is.

Any help would be appreciated as this is annoying the hell out of me!

Thanks in advance all!

 

[mjw21a]

Not too sure mate. I made sure when I got my Delta's that I got PWM fans, and each fan draws power directly from my PSU. Funny thing is that on my H100 the fans never ever ramp up beyond their minimal speed. A good thing too as they're audible from downstairs even then, and they're only pushing 80CFM each at that point.

 

[muddocktor]

That sounds to me like they might be overloading your fan controller or something of that nature. What kind of wattage per channel is the fan controller rated for? Those FFB fans of yours pull 17.4 watts in steady state and probably pull close to 30 watts at first startup, until they get up to speed.

 

[Yevans]

That's the strange thing, unless I have wired these fans wrong they are both pwm. The noise at full wack i want is just crazy. The girlfriend isn't too keen on it but I want those temps down!

Hmmm, that's what I thought at first, but the controller can supply 50w per channel so even at peak it should be alright. Plus I think the fan that is working fine draws more power. When I increase the supply to the fan it simply pulses at a higher speed as if it is still trying but not getting past the pulse issue.

 

[mjw21a]

You could always rewire the fans so that its drawing power straight from the PSU and use the PWM function to control fan speed.....

 

[Yevans]

You could always rewire the fans so that its drawing power straight from the PSU and use the PWM function to control fan speed.....

For this do you mean to wire the power through a molex and run the PWM pin through the fan controller?

 

[mjw21a]

Yup. So long as the controller can do pwm.

 

[muddocktor]

Yeah, just split the hot and negative wires out of the 4 pin plug, then wire them to a regular 4 wire molex connector such as used to supply old skool IDE hard drives and IDE DVD drives. You can even use the PWM mobo headers to control the fan speeds instead of your fan controller if you want to. I have my monster Sanyo Denki counter-rotating Beast rigged up that way because of the tremendous power draw of it.

 

[mjw21a]

Its easily the best way to run hi performance fans..... Although my fans do have a habit of tripping the over voltage and powering down my PSU.... I really should wire them of separate connectors

You want the red and black wires going to one of these:



The position of the red on my fans is the far left pin and the black the one to the right. The two right pins will be vacant.

 

[Yevans]

Ah thanks, that may help. After a bit of digging I found my fan controller doesn't do PWM, simply ramps up and down the voltage to control the fan. Running the PWM from my motherboard may well be the best way to go about it. Just gotta find a free molex now...

 

[amora]

Err just in case no ones made this clear.
Don't drive the motor using the mobo headers, you'll kill your mobo header.

Only use the PWM signal pin from the mobo, don't try to power it from the mobo technically by using a transistor you can drive any motor using pwm

 

[mjw21a]

Err just in case no ones made this clear.
Don't drive the motor using the mobo headers, you'll kill your mobo header.

Only use the PWM signal pin from the mobo, don't try to power it from the mobo technically by using a transistor you can drive any motor using pwm

The red and black wires are the voltage wires, and a molex will not plug into a mainboard header

 

[Yevans]

Err just in case no ones made this clear.
Don't drive the motor using the mobo headers, you'll kill your mobo header.

Only use the PWM signal pin from the mobo, don't try to power it from the mobo technically by using a transistor you can drive any motor using pwm

Haha don't worry I am definitely not doing that, I don't particularly want the fan to try and draw 20W+ from the mobo! That would be one costly mistake.

 

[amora]

The red and black wires are the voltage wires, and a molex will not plug into a mainboard header

No true bud. "Molex" is a company, MOLEX INC.. Your use of the word is to describe the 4-pin female connector coming from your PSU, which is correct, it is a Molex brand connector. In fact Molex encompasses all sorts of headers and connectors. That tiny female fan tale you plug into your mobo? That to is a Molex connector.

In the non electronic community the word molex is used as a generic term. It isnt lol

Just an FYI

 

[amora]

Haha don't worry I am definitely not doing that, I don't particularly want the fan to try and draw 20W+ from the mobo! That would be one costly mistake.

Although power(watts) is derived and related to ohms law given by V = I*R, and consequently P= I * V.

It's actually the current(I), which will destroy your motherboard.

ie at 20watts you're "drawing" 1.2ampers of current

 

[freeagent]

I have the same problem when I run fans off of mine that dont have a sense wire (yellow)

If you can attach a fan that has sense wire, then just splice a connection useing the + - and you can use the afc as a slave, while controlling rpm's with wichever fan has the sense wire.

Or you can plug it into a fan header on your mobo and control the power thru the bios..

I use the optional_fan headers on my board, because they deliver better power control rather then useing the built in fan profile set by the manufacturer

 

[amora]

Oh one other thing, don't try to split the PWM signal wire to many ways, It's rather weak and sometimes will cease to function. I'm also unsure of how much amperage the pin can source so you might want to use transistors to amplify the signal...

Video demoing this coming in about 5 min, still uploading to the tube...

 

[mjw21a]

No true bud. "Molex" is a company, MOLEX INC.. Your use of the word is to describe the 4-pin female connector coming from your PSU, which is correct, it is a Molex brand connector. In fact Molex encompasses all sorts of headers and connectors. That tiny female fan tale you plug into your mobo? That to is a Molex connector.

In the non electronic community the word molex is used as a generic term. It isnt lol

Just an FYI

That would be why included a picture of one dude, to avoid confusion.

 

[Yevans]

Thanks for the help all. Just the beast of the two is sat pushing through my cooler and it is providing temps better than 2 gentle typhoons even at its lowest speed setting (albeit it at a slightly greater noise level). Next plan is to put another as a pull to see what it will give. Even with diminishing gains it could be interesting.