Fan Speed Controller for Return Pump Control?

Because power consumed equals work done. Move more water, use more power. Throttle a pump, decrease power used.

You will probably need a pressure rated pump though for that head.

 

D@mn you guys got to me to fast. I've been doing reading since making that post and I'm now fairly comfortable with the idea of less water movement = less power consumption. Thanks though powerman.

 

I'm real comfortable with it. It's been paying my bills for 20 years.

VFDs are more efficient, but running fans at half speed is simply moving less air. There are losses involved, but the work to be done in any system is the cubic feet needed moved. System engineers still design a fan to move the required air. Nobody installs twice the fan they need just so they can run it at half speed. If a situation calls for less output, it is more efficient to reduce speed than it is to throttle flow. But as was mentioned those are 3 phase industrial applications.

You still will need a pressure pump that can give the adequate flow at the head pressure you need. It may very well do 1200 gph at zero feet, just make sure it can do the 600 gph at 11 feet. My skimmer only processed 350 gph. My fuge which was fed independently only needed 100 gph. So we are only talking a NEED of 450 gph. Like I said I did 600-650 gph.

Just figure up what you need and then work to supply that. Moving more than that is unnecessary.

 

On various work applications I use 6" 500 CFM oversized fans at ~70% to reduce noise. A larger fan spinning lower RPM produces the same airflow with only the noise of the air itself and no mechanical hum.

Right. Thats the trick. Finding the minimum threshold.


On the topic I found something related in the 1350 Coral Tank thread on RC.
http://www.reefcentral.com/forums/showpost.php?p=17764957&postcount=4769