GREETINGS: easy one, IF the pump is a name brand, and a FRANKLIN motor what size?? hp. ?? Be sure and grease the coupling internally between the pump and motor, BE certain the motor is VERY well grounded, and BE CERTAIN there is complete electricial disconnect between all power, even the neutral...
GREETINGS: I vote for the dial indicator(S)... ALSO be sure the pump base is grouted in place, the piping does not pull the pump out of allignment, and recheck after a day or two... I have been known to use TWO(2) dial indicators, one behind, the other to check for shaft paraellness ?, or 180...
MY MONEY was on WRONG rotation TOO.... It does happen... There are phase meters from amprobe that allow you to hook up LARGE motors right the first time.
GREETINGS: HARMONICS... WELL ALLEN BRADLY has a new VFD drive out, it has 6, 12, or even more pulses on the input side to balance out the input SPIKES...We see these problems on oil well pumps ... down -hole submersiables A tough app. LAST VFDS are now sweet, I started out 34 years ago with only...
GREETINGS; How long was the pump run with no , discharge piping attached?? If you operated it for more than a few seconds, the IMPELLER could have unseated itself from the wear/sealing ring, or even pulled the thrust bearing out of its housing and, not allowed it to "fall" back in place... I...