Seasonic MagFlow 120 mm 1225 PWM Case Fan Review ITTSB.EU

[Kiriakos GR]

I got motivated after the single MagFlow DC Fan testing, so to proceed and at triple DC fan testing. 

Unfortunately I believe that Seasonic it should return back at R&D room for further corrections.

At my single DC fan tests, I did spot at PWM signal circuit a critical sensitivity issue.
Now at double or triple DC fan setup, the problem becomes MORE SEVERE and or obvious.

PWM this is a signal generated by a chip over the motherboard, this dictates FAN speed due percentage change.
DC Fan industry white paper they inform that any DC fan it should obey at PWM range of 30% up to 99%.
This is also obvious at Seasonic MagFlow DC Fan at single unit testing, and so there is no problem.

At DC fan combination setup, of several connected MagFlow DC Fan in series (parallel signal input connection), a FAIL issue detected.

Triple MagFlow at 75% PWM we have a FAIL condition so them to operate.
At 80% PWM all three DC fan operates up to 99% PWM.

My technical opinion, there is a wrong control chip selection within MagFlow 1225.
PWM input this is extremely insensitive.   
At Seasonic they should immediately investigate, to catch-up the issue prior the arrival of customer complains.

   

[Kiriakos GR]

I did some further research about PWM specifications white paper just for me to be at 150% at the safe side regarding doubts.

From Noctua PWM specifications white paper

PWM control input signal

As specified by Intel (c.f. “4-Wire Pulse Width Modulation (PWM) Controlled Fans”, Intel
Corporation September 2005, revision 1.3), the square wave type PWM signal has to be
supplied to the PWM input (pin 4) of the fan and must conform to the
following specifications:
• Target frequency: 25kHz, acceptable range 21kHz to 28kHz
• Maximum voltage for logic low: VIL=0,8V
• Absolute maximum current sourced: Imax=5mA (short circuit current)
• Absolute maximum voltage level: VMax=5,25V (open circuit voltage)
• Allowed duty-cycle range 0% to 100%

At single MagFlow testing, I had to boost signal voltage level higher than VMax=5,25V, and actually I had to boost my signal generator at max and up to 6.8V

The first simplest explanation of what got wrong with MagFlow design, this is PWM input issue, this has tremendously low input resistance (low impedance), this causes unwanted loading at PWM signal and source.
By doubling or tripling the load over the PWM signal source, the driving signal voltage output, this gets out of specifications, and its not sufficient any more so to drive two or more fans.

The second simplest explanation of what got wrong with MagFlow design, internal chip this is unable to perform signal PUL-UP and to amplify PWM signal as needed.

I did notify Seasonic by Twitter, I did report the issue at Seasonic Nils (EU), now the ball this is at their court.
In summary, MagFlow 120mm it does have issues,  I am unaware if newer MagFlow-RGB this has also similar problems.

I would expect that Seasonic will do a public announcement, about of what they will plan to do.
If they try to hide this under the carpet ? Then too bad for them.   
 
   

[Kiriakos GR]

Last major chapter DC motor technology in Use 

Seasonic this is not a DC fan manufacturer, it just used other expert partners, so them to build their MagFlow fan.
Seasonic  mention hydro-bearings at the specs, but this is not 100% true.
Seasonic made their Unboxing-Magflow-3-Pack.mp4 (video), just at a few frames they do appear motor internals, along Noctua SSO2 axle support system.

I am not trying to present my talent as best industry Spy 
But I will demonstrate my last pack of findings at the photographs below.   

In summary:
WIDESKY Design Corporation CO., LTD  Taiwan  (R.O.C.)  = exterior design
Electric DC motor = OEM factory which also produces Noctua SSO2 technology.
The unknown information, this is whom is THE GENIUS which provided the DC motor control PCB? 

My closure:
Seasonic within past months it delivered several three-pack samples at unworthy hands, all product reviews which I did read they are worthless.
Very few bothered to test a single DC fan, and no one tested the complete three fan combination.

I am a Professional tester (certified electrician) along over 30 years of field experience, I hope that SEASONIC they will shown as generous to me, and pay few bills of my Blog as thanks for the delivered professional feedback.
Simple as that...   

[overvolt]

As far I know from latest production of AWG ( signal generators), they have medium amplification up to 10Vpp.
Kiriakos did use at this test his AWG of 16Vpp.

And so, there is no doubt that Kiriakos did use one of most powerful AWG of our times.

[Kiriakos GR]

As far I know from latest production of AWG ( signal generators), they have medium amplification up to 10Vpp.
Kiriakos did use at this test his AWG of 16Vpp.

And so, there is no doubt that Kiriakos did use one of most powerful AWG of our times.

Well I have and a another powerful one, the PHILIPS PM5134 Function generator at 20Vpp, but 10Vpp for pulses.
https://www.ittsb.eu/DMM-Test-tools.html
But neither this monster succeed to fightback the primary issue.   

[Andrew-88]

My closure:
Seasonic within past months it delivered several three-pack samples at unworthy hands, all product reviews which I did read they are worthless.
Very few bothered to test a single DC fan, and no one tested the complete three fan combination.

I am a Professional tester (certified electrician) along over 30 years of field experience, I hope that SEASONIC they will shown as generous to me, and pay few bills of my Blog as thanks for the delivered professional feedback.
Simple as that...

I do not have much of faith that Seasonic will react with the appropriate respect at Kiriakos, for the received professional feedback.
Only a serious western brand will do that, so to protect consumers and their fame.

Corsair become also reseller of keyboards and of other computers accessories, many are true FAIL products.
Never hold them self's responsible, never did any products recall.