Well, I’ve read so much information that I can’t make a decision and I’m hoping you can help. I have two basic questions: should I switch to variable and, if so, which one? Using the label on the side of my current single speed motor and the info on your website I’ve determined that I have a B661, 1.25 HP total (.75 hp x 1.67 SF), 230V, 11.2/6.0 - 5.6 amp. After calculations I’m showing that my current pump uses 1.38 kw at 3450 rpm. Since the kw will vary on the variable pumps, I’m not sure how to compare to see if it makes sense to switch to variable. Any guidance?
I would recommend the variable speed motor for your application. Something like the ECM16SQU would mate up with your pump. The ECM16SQU is a 1.65THP variable speed motor. The B661 motor will be pulling 1,288 watts while running. You can see from the chart below that a variable speed will run at dramatically lower watts if running below 3450 RPM.