WorldWide Drilling Resource

Starts Per Day Part 2 So the man with the burned out motors asked me how to fix the problem. As I’ve said in the past, I like to give options. So when I asked him what his system looked like, he told me they were drawing water out of a river to a wet well, through the pump, then up a cliff to a greenhouse where they had an array of tanks and a pressure switch. Option number one was to increase the number of tanks by three. This was also a very costly and messy way to fix the problem. Option number two was to get rid of the tanks and switch, and just use a pressure regulator to send some of the water back to its source when they weren’t using it and let the pump run for 8 hours a day. A little more practical, but again requiring someone to figure how to make it work right. Option number three was to get a VFD (variable frequency drive) since it has a soft start and coast to stop, it would not require all the amperage across-the-line starting did. Yes, there was going to be some cost, but it was much more doable. I was in Honolulu once doing a training seminar on pumps and there was an associate from Lesson Motors training the same group on motors. He told the group most people think electric motors run on electricity, but they don’t. They run on smoke. Yep, I always say, “He’s dead Jim, pick up the tricorder and move on.” Once you’ve let the smoke out, you can’t put it back in, at least it isn’t worth it with smaller motors. I’ve been told 40 horse- power is the break-even point. If the motor is less, change it out; if it is that or more, maybe you should rewind it. I hope this has helped you under- stand a motor’s life is very dependent on how many starts you put it through. In my world of residential and small sprin- kler pumps, this means the tank in the system must be large enough to keep it off long enough, so it only starts the number of times suggested. You cool a submersible motor by ei- ther running it and letting the water move past it fast enough, or by making sure it goes off and stays off long enough to make up the time. Oh by the way, smaller motors, defined as ½- to ¾-horsepower, have a number of 300 starts per day single-phase. One-horsepower or greater single-phase are 100 starts per day. Three-phase is 300 starts per day up to five-horsepower and anything over is 100 per day. Good luck, and watch those starts. Bill Bill Corey may be contacted via e-mail to michele@ worldwidedrillingresource.com It’s almost too late ~ get in the Annual Buyers Meet Sellers issue. Call Brenda or Jan today! 850-547-0102 46 OCTOBER 2016 WorldWide Drilling Resource ® by Bill Corey Pentair Water Training Institute