Electric motors have had a huge impact on the pump industry.
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Improved motor starters help Fabri-Kal achieve its green vision.
An argument in favor of IEEE-841's provision for motor bearing protection.
The global economic downturn has resulted in an unprecedented attempt by world governments to help stimulate their individual economies, with the hope that these combined efforts will have a cumulative effect of breaking the downward spiral and lifting the global economy out of its crisis.
Energy efficiency and reduced consumption are important issues in the pump and motor marketplace. Over the long term, electricity costs will continue to increase regardless of our actions.
The industrial motor world has a new specification available for defining the requirements of general purpose, severe duty motors in the 250- to 3,000-hp range.
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. The torque and speed characteristics of these motors are a close match to those required for centrifugal pumps.
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. We will also focus on the three-phase design as it provides a more intuitive understanding of induction and the magnetic fields that are produced. We will discuss the operation of single phase motors in the May 2011 issue.
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. Otherwise, the disc coupling never factors into our daily routine.
Latest Motors Articles
Electric motors have had a huge impact on the pump industry.
Improved motor starters help Fabri-Kal achieve its green vision.
Why and how do leading OEMs choose a variable speed motor for their equipment? While rated efficiency has been an important driver in the past and will continue to be one in the future, leading equipment and machinery manufacturers now use sophisticated variable speed technologies to radically redefine their products.
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. Though it is impossible for the maintenance department to predict when a pump will stall, such maintenance techniques are often the result of poor motor design.
Significant energy and money savings are realized when using variable speed motors controlled with drives.
For the first time, the United States Department of Energy (DOE) adopted energy conservation standards for small electric motors in February 2010. DOE determined these standards will result in significant conservation of energy, and are technologically feasible and economically justified. Motors covered under these new regulations range from ¼ to 3 hp and include single and poly phase two, four and six pole general purpose motors in NEMA 42, 48 and 56 frames and corresponding IEC equivalent motors and frames. The new regulations will take effect in 2015, which is five years after the original publish date.
A paper or an electronic work order system can be used to capture alignment data.
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.
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. We will also focus on the three-phase design as it provides a more intuitive understanding of induction and the magnetic fields that are produced. We will discuss the operation of single phase motors in the May 2011 issue.
Columns and Blogs
In this multi-part series, we will investigate several aspects of centrifugal pump efficiency.
First of Five Parts
Since the original publication of this draft standard in the January 2008 issue of Pumps & Systems, I have received feedback, encouragement, numerous questions and criticism. The draft listed three basic levels of repair.
The McGraw-Hill scientific dictionary [5] states that a volute is "a spiral casing for a centrifugal pump... designed so that speed will be converted to pressure."
