Pumps & Systems, March 2013
Last year, a Pumps & Systems reader asked about matching variable frequency drives (VFDs) and motors.
Advanced motor protective relays provide superior protection for motors and pumps. pump system optimization
Last month, we ended with a discussion of the relationship between peak and RMS (or effective) voltage.
Following the development of variable frequency converter drives during the 1990s, totally enclosed fan-cooled (TEFC) AC induction motors became viable options for replacing DC motors in pumping applications.
With highly reliable electrical systems, protective relays may be called upon to operate very infrequently.
After spending money on a powerful new pump and the motor to run it, the next big decision is how to connect the two in a way that maximizes their efficiencies and protects them from normal wear and tear.
Proper alignment of the pump shaft with the driver can reduce vibration and significantly improve reliability.
A flexible coupling's primary functions are connecting two shafts, transmitting power from a driver shaft to a driven shaft and accommodating the misalignment between them.
Couplings are often forgotten until a project is nearing its end.
It has been said that Washington, D.C., is the home of the largest invertebrate population in the U.S.