Different fan controls (was: Panaflo -- at last!)

Pjotor · Post by **Pjotor** » Fri Oct 08, 2004 1:05 am

Just got my three Panaflo L1A fans in the mail. So what?

Well, these fans are sold only by one (1) company in Sweden. They have been out of stock for at least a year

, so it's been extremely frustrating reading about these fans and not being able to use them myself. Now, if only a Swedish reseller would get those SmartDrives too...

BTW, all of them are "Japanaflo" models -- just checked. I can't wait to slap one of those babies in my ZM400B-APS.

For those in Sweden: They are available at www.overclockers.se. Get'em while they're hot!

Pjotor · Post by **Pjotor** » Fri Oct 08, 2004 1:06 pm

Update: L1A mounted in PSU. I didn't know it would make such a difference (for the better).

I'm much happier now!

ascii · Post by **ascii** » Fri Oct 08, 2004 3:52 pm

Grattis, mannen!

jones_r · Post by **jones_r** » Fri Oct 08, 2004 5:01 pm

I'm pretty disappointed with the Panaflo L1A. Can't spin at less than 700 rpm.

Post by **Rusty075** » Fri Oct 08, 2004 5:28 pm

jones_r wrote:I'm pretty disappointed with the Panaflo L1A. Can't spin at less than 700 rpm.

Why would you want it to?

That would require less than 5volts. An L1A at 5v is essentially inaudible, (something like 2dBa @1m) unless you have absolutely no background noise at all.

jones_r · Post by **jones_r** » Fri Oct 08, 2004 6:01 pm

Rusty,
The L1A at 700 rpm is audible to me when the room is very quiet. It is the only fan in my computer (the psu is cooled by passive phase change coolant, and the VGA card by the VM101 fanless heatsink).

Using the original 80mm fan that came with the HT-101, it cools my XP2400 (2000 MHZ) CPU at both idle/load when spinning at only 380 rpm (about 4 CFM).
At 380 rpm, when the fan does not touch the heatsink, I can say it is almost totaly inaudible, even when the environment is silent. The Panaflo at 700 rpm is like an F16 in comparison.

Edward Ng · Post by **Edward Ng** » Fri Oct 08, 2004 6:37 pm

Looks like you'll need to look into an alternate fan entirely, or at least a better sample of an 80mm L1A.

That, or maybe add some noise to your environment to cover it up, like music!

Post by **Rusty075** » Fri Oct 08, 2004 6:37 pm

Whatever works for you is all that matters, obviously.

Out of curiousity, how are you controlling the voltage and monitoring the RPM's?

burcakb · Post by **burcakb** » Fri Oct 08, 2004 10:16 pm

Yeah? rpm? how?

FWIW, I'm also displeased with the noise of the japanaflos I have. They make a chug chug bearing sound even at 5V that I can hear from where I sleep. However, considering the airflow capacity and lifetime noise characteristics, I find them a more reliable fan to use in PSUs.

I feel the acoustifan (or any globe fan in general) or the nexus has much better sound characteristics than the panaflo. They usually fail in the cfm department though

Edward Ng · Post by **Edward Ng** » Fri Oct 08, 2004 10:22 pm

burcakb wrote:...I feel the acoustifan (or any globe fan in general) or the nexus has much better sound characteristics than the panaflo. They usually fail in the cfm department though

Glad to see I'm not the only one who feels this way...

...now if only we can find a cheaper 80mm or 92mm, sleeve-bearing fan by Globe!

-Ed

jones_r · Post by **jones_r** » Sat Oct 09, 2004 8:08 am

Out of curiousity, how are you controlling the voltage and monitoring the RPM's?

Rusty, I'm using the T-Balancer.

Edward Ng · Post by **Edward Ng** » Sat Oct 09, 2004 8:24 am

In that case, Russ--you were right!

Post by **Rusty075** » Sat Oct 09, 2004 9:02 am

jones_r wrote:Rusty, I'm using the T-Balancer.

As an experiment, try connecting the L1A directly to the 5v line. L1A's really don't like PWM. You'll lose all the nice features of the T-Bal, but it would let you hear what the L1A really sounds like at 700 RPM.

(it's also possible that you've got a cruddy sample of an L1A...that seems to be happening to me more and more)

jones_r · Post by **jones_r** » Sat Oct 09, 2004 9:04 am

In that case, Russ--you were right!

Maybe, and then maybe not. PWM noise is not something that all fans suffer from, and it doesn't seem like the sample of L1A that I got (made in Japan) suffer from it at all (the noise @700 is kind of a constant quiet whine). The only thing is that it can't spin below 700 rpm reliably. Once I will get the attenuators which do DC conversion, we'll know if he was right or wrong.

I don't have any way to check the L1A @ 5V.

Edit,
Now that I checked again (put my ear right against it), the L1A does seem to make the PWM noise (constant clicking noise), and the reason I didn't hear it before, is because the whine is louder and hence cover the clicking noise.

silvervarg · Post by **silvervarg** » Sun Oct 10, 2004 11:33 pm

Jones_r:
The only thing is that it can't spin below 700 rpm reliably. Once I will get the attenuators which do DC conversion, we'll know if he was right or wrong.

I don't have any way to check the L1A @ 5V.

The attenuators does not do DC conversion, they simply smooth out the PWM curve a bit more. Do you trust the RPM value of the fan controller? I woudn't.
Have you tried to connect the fan via a fanmate set to lowest setting (that will give you about 5V). This makes a huge difference to the panaflos I use.

frosty · Post by **frosty** » Mon Oct 11, 2004 7:18 am

Pjotor, congratz, sweet are they not? I still recall my noisey Adda's and how they would not undervolt or start at 5 v and how cool it was last summer to install those swirling 80 l's.

Curios to see what your freight would have been to Sweden if someone here had just sold you some of theirs?

Pjotor · Post by **Pjotor** » Mon Oct 11, 2004 10:21 am

frosty wrote:Pjotor, congratz, sweet are they not? I still recall my noisey Adda's and how they would not undervolt or start at 5 v and how cool it was last summer to install those swirling 80 l's.

Curios to see what your freight would have been to Sweden if someone here had just sold you some of theirs?

Thanks frosty.

I have used Adda fans before -- although the noise haven't concerned me, their air transport capabilities have. Too weak for me to dare put one in the PSU.

Freight costs -- I have absolutely no idea. I got them for SEK 125 a piece (close to 17 USD

) but hey, what could i do? I got three of them though, so it should last a while.

Too bad they don't come in other sizes than 80mm (in Sweden, that is).

jones_r · Post by **jones_r** » Tue Oct 12, 2004 7:30 am

The attenuators does not do DC conversion, they simply smooth out the PWM curve a bit more.

That's not entirely correct, the attenuators do DC conversion, in fact that's the only thing they do. And btw, The T-Balancer PWM's are smoothed to begin with.

Do you trust the RPM value of the fan controller? I woudn't.

Even if it's not totally accurate, setting the controller lower than 380 rpm makes no perceivable change in SPLs, so It doesn't really matters. Also, when I lower the rpm's further down from 380, everything feels very linear, there are no big jumps at all, the rotors just keep slowing a bit more, until they stop at 0 %.

Have you tried to connect the fan via a fanmate set to lowest setting (that will give you about 5V). This makes a huge difference to the panaflos I use.

No, I have no fanmate. The difference in SPLs between the panaflo at 100% and 40% (lowest precent before it stops spinning) is huge, but still isn't as quiet as the other fan at 380 rpm.

ferdb · Post by **ferdb** » Wed Oct 13, 2004 8:21 am

My 80mm Panaflo L1A's run down to about 300rpm, although not with the T-balancer. The T-balancer PWM seems to cause a lot of problems with fans at low speeds including adding noise. I find it essential to HEAVILY filter the T-balancer outputs. Try putting something like a 47 ohm resistor in series with the fan and a 1000uf 16v cap across the fan. Adjust the resistor value to give you the speed range you want. Fanmates are just a transistor hooked up as an emitter follower with a pot connected to the base of the transistor to vary the output voltage. They are pure DC output, the drawback is a limited power rating because they get hot.

Jan Kivar · Post by **Jan Kivar** » Thu Oct 14, 2004 7:25 am

ferdb wrote:Fanmates are just a transistor hooked up as an emitter follower with a pot connected to the base of the transistor to vary the output voltage. They are pure DC output, the drawback is a limited power rating because they get hot.

Nope, they're based on a regulator circuit, like this.

Cheers,

Jan

silvervarg · Post by **silvervarg** » Tue Oct 19, 2004 2:46 am

Silvervarg:
The attenuators does not do DC conversion, they simply smooth out the PWM curve a bit more.

Jones_r:
That's not entirely correct, the attenuators do DC conversion, in fact that's the only thing they do. And btw, The T-Balancer PWM's are smoothed to begin with.

Rechecking at http://www.mcubed-tech.com/eng/produkte.htm and reading about the attenuators you can clearly see that they do not[/b) do DC conversion. They simply smooth out the PWM curve a bit.

In fact the attenuator is only a fan Y-splitter with a single condensator.
And a pretty hefty price for that condensator I might add.

Even mcubed-tech themself do not state that it does DC conversion. They say that it does "converts digital voltage into curves". Pure DC is not a curve, it is a line.

Look at the PDF file for the attenuator. You can see a rather good image of what the attenuator is.

ferdb · Post by **ferdb** » Wed Oct 20, 2004 9:30 am

Jan Kivar wrote:
ferdb wrote:Fanmates are just a transistor hooked up as an emitter follower with a pot connected to the base of the transistor to vary the output voltage. They are pure DC output, the drawback is a limited power rating because they get hot.
Nope, they're based on a regulator circuit, like this.

Cheers,

Jan

You are quite right. My first impression when I looked at the PCB was that it was merely an emitter follower circuit with the base connected to an adjustable voltage divider. But when I pried the heatsink back enough to actually read the part number it turns out to be an LM7805. I'm not entirely convinced that it's a better solution than a simple emitter follower however. The drop out voltage is higher so the maximum voltage out is lower with the 7805 than it would be with an emitter follower. The minimum output voltage is also restricted to no less than 5V, whereas there is no such restriction on an emitter follower. In some cases I've had to insert a series resistor with a fan because the Fanmate wouldn't let me run it as slow as I wanted. The 7805 is also more expensive than a simple transistor, but this may not have a very important impact on the cost to market of the device vs the markup. Another side effect I have noticed is that at certain voltage range settings it will break into a low level RF oscillation. Nothing large enough to have any impact on it's function, but possibly an interference source.

Thanks for correcting my misinformation.