[SOLVED] Understanding case fan specs

[Khulafu]

Hi!

As the title says, I need clarification on understanding what is listed on case fan spec sheets, i.e.

Airflow: 56.3 CFM/ 95.65 m³/h
Static Pressure: 2.20 mm H₂O
Current/ Voltage: 0.08 A / 12 V

How I understand them is that these numbers are their max, like the fan achieves 56.3 CFM at maximum RPM/100%. Am I correct in this manner of understanding? It would really be appreciated if someone can affirm or correct the way I understand listings like these.

Thanks and have a good one!

 

[Lutfij]

Am I correct in this manner of understanding?
Yes though you should give or take 10% from that number due to variance in samples, i.e, +/- 10% for all values.

Make and model of said case fan? Seems to have good static pressure, if it's a 120mm case fan.

 

[Khulafu]

Am I correct in this manner of understanding?
Yes though you should give or take 10% from that number due to variance in samples, i.e, +/- 10% for all values.

Make and model of said case fan? Seems to have good static pressure, if it's a 120mm case fan.

Thanks for the reply! I just ripped it off the Arctic P12 spec sheet page as it was the first thing i could get a hold of (since im personally using 5 of them in my rig). Glad to know I've been on the right track about the spec sheets.

 

[Paperdoc]

Yes, as above. But the static pressure rating (in mm water) is a bit different. With any fan actual air flow rate depends on what resistance the air experiences, expressed as the backpressure it must overcome. So max air flow rate is at max motor speed and ZERO backpressure - free air flow with no impediment. Max Static Pressure also is measured at max motor speed as the others, but it is the imposed backpressure (by restricting air flow) at which NO actual air flow will happen. Above that backpressure there's no flow. Typically a Static Pressure over 2 mm water (as in your example) (a bit higher is even better) is a fan that CAN force reasonable air flow though a rad or heatsink fins. Case ventilation fans with few thin airflow passages to restrict them often have ratings less than 1 mm water.

 

[Khulafu]

@Paperdoc
I see, thank you for this. I am aware that these numbers are affected by a lot of variables, just not as in depth as how you have explained. I appreciate it.