As a follow up on my AC Motors series, I thought it would be a good idea to provide a short overview of work, power and torque as it applies to the AC motor.
Couplings are often forgotten until a project is nearing its end.
Named for a technique commonly used on failing pumps, "percussion maintenance" - where a technician beats on the pump's stalled motor with a hammer or rubber mallet - often indicates motor deficiencies in his diaphragm pump.
The low voltage motors market is highly consolidated, with the top five participants accounting for more than 75 percent of the market revenues as of 2009. Low voltage alternating current (AC) motors dominate the industry, generating 92.1 percent of market revenues for 2009. That number is expected to increase to 95.9 percent by 2016, with a Combined Annual Growth Rate (CAGR) of 7.6 percent between 2006 and 2016. Low voltage direct current (DC) motors, on the other hand, are expected to have a negative 3.4 percent CAGR between those years.
Last month, we studied the properties and effects of resistive, inductive and capacitive loads in an AC circuit.
Proper alignment of the pump shaft with the driver can reduce vibration and significantly improve reliability.
Although a number of AC motor designs are used, the induction motor is, by far, the most common and will be the topic of this column.
Because operational costs ride on efficiency determinations, accurate measurements of losses occurring within the motor are paramount. The reliability of efficiency data is key to any energy-savings plan, and knowing the meaning behind the rating can make or break a smart purchasing decision.
Construction features are key to vertical motor application and maintenance.
The pump industry is the largest purchaser of electric motors in the United States.
Due to the expense and labor required, most facilities need to maximize the life of their motors.
Most of us probably never notice the spinning cylinder mounted between the pump and motor, except how easy it is to dis/assemble when a pump or motor is changed out.
Due to the expense and labor required, most facilities need to maximize the life of their motors. Electrical, insulation resistance and thermal measurement are three tests that can troubleshoot motors, drives and associated electrical panels and prolong their operational lifetime. Thermal imagers can detect potential problems and insulation resistance and electrical tests can determine the cause.
All electric motors (motors) have a housing that contains the working components of the motor. In the U.S., the enclosure describes this housing.
One of the major impacts on motor life is common sense—or maybe the lack thereof!
A large wastewater processing plant experienced continual problems with its influent raw wastewater pumps for several years.
It is impossible to balance line-to-line voltages perfectly in a three-phase circuit.
Mechanically generated sparks, electrostatic discharge and high surface temperatures are all potential ignition sources in explosive atmospheres.
Last September, we spoke about the importance of pipe-to-piping alignment, evaluating actual numbers, and tabulating stress values as they approach yield stress of pipe at various values of misalignment. This time, we will discuss the effects of pump-to-motor misalignment, beyond hype or generalities, by numerically quantifying the conclusions.