sizing vfd 3

[tomato5]

need assistance to sizevfd to run a pump to deliver 400 gpm and 150 ft head, and also 600 gpm at 200 ft make any assumptioms take 50 hertz

tyvm

 

[LionelHutz]

Well, you simply pick a VFD that matches the motor once you figure out the motor you will be using.

 

[jraef]

Yes, first size the pump for the task, the motor for the pump, then the VFD for the motor.


"Will work for salami"

 

[TenPenny]

Roughly 25 hp for the 400 gpm unit, and 40-50hp for the 600 gpm unit.

 

[jraef]

That's making some assumptions about the pump efficiency, and likely that it is water that he is pumping.

HP = GPM x Ft. (head) x specific gravity of the fluid / 3960 x pump efficiency. So 400 x 150 (SG of water being 1) / 3960 = 15HP, so you must be assuming about a 60% efficiency to get to 25HP.

On the other one I get 30HP w/o eff, so same thing, at 60% eff it comes to 50HP.

Those are conservative number, good for estimating I suppose.




"Will work for salami"