Series 2 fans to get 6v each. What about RPM sensor wire?

[tempoct]

Can I still use them separately?

Says I plan to do the following setup, which suggested by several members;

+12V _____+Fan1-_____+Fan2____G

Fan1 and Fan2 are identical. This case, I leave the RPM sensor wire alone for both fans.

Or I can do this?

• +12V _____+Fan1-_____+Fan2____G
  ....................|...................|
  ....................|...................| RPM2
  ....................| RPM1..........|
  ....................|...................|
  .............MB fan socket 1...|
  .........................................|
  ..................................MB fan socket 2

Good to go?
(fans are Panaflow 60mm FBA06A12L1A)

[Tibors]

Here is my solution with only tacho for Fan2. I don't think you can use the tacho for Fan1 since that fan does not have a proper ground.

Do you really need both tacho signals?
If both fans run normally, then they should run at (about) the same speed.
If Fan1 breaks down and shorts, then Fan2 will go at full speed.
If Fan 1 breaks down and doesn't short, then Fan2 will stop too.

[TomZ]

I agree with Tibors, the "high" fan is referenced to approx. 6V instead of ground, so the MB won't be able to measure the speed.

Will the fans start reliably at 5V? Maybe you should just connect them both to the +5V rail?

[tempoct]

I don't know if the fan will start reliably @ 5v. I plug it in the 5v rail and it start. Not sure how reliable it is. The spec on Panasonic site indicate minimum voltage is 7v.
Anyway, the fan is SO smooth. MUCH better than the "SilenX" I have So happy about the panaflo now.
I also have the 80mm version in the shipment. I might try it out @ 5v as a single intake.

[tempoct]

Note: For the 60mm, Digikey actually ship the NMB instead of Panaflo. I guess they are the same thing now (since they merged)

I originally tested them @ 5v and they are quite smooth, however, they are loud @ 12v. The series 6v setup is still too loud for me now

The 6v series start up has a little doubt in reliability. I test by put my finger to stop one of them or both of them, it take about 1s+ to restart itself. When one fan is stopped, another fan tends to do the same thing. I guess it might have to do with the variable internal resistance of the fan itself.

So, I decide to run parallel on 5v line instead. They are quiet but barely move air. I might need to add the in-take fan.

For the 80mm, I got the Panaflo brand. Made in Japan. It's loud! Not sure why... even @ 5v. It's louder than the 60mm NMB I mentioned above (@5v). The bearing sounds not smooth.

Do I need any "breaking-in" for the Panaflo? I'm kinda frustrate with it.

[BrianE]

For the 80mm, I got the Panaflo brand. Made in Japan. It's loud! Not sure why... even @ 5v. It's louder than the 60mm NMB I mentioned above (@5v). The bearing sounds not smooth.

Do I need any "breaking-in" for the Panaflo? I'm kinda frustrate with it.

It might be old or factory seconds... I don't think Panaflos are made in Japan anymore, and haven't been for a while. Does it have a serial number on the label? Something like 5Hxxxx or something with a number and then a letter?

It'd be bad if junk Panaflos are still being sold these days. They used to be very popular here, but people found they weren't that quiet and stores selling "seconds" didn't help. They are pretty durable though.

[tempoct]

The only other number I found is 4C19ED... Is this the serial number?

[Chris Chan]

4c is march 2004, they are not good fans. Dorothy Bradbury explained in an old thread that March-May 2004 the chinaflos weren't good - the factories got lazy and the management in Japan wasnt checking up on them so they were building stuff with worse tolerances. After the Minebea takeover the China factory straightened out, now 4H and up fans are good as japanaflos.