TechArchive

Original article date: November 1999 Looked at another way, the latest frequency inverters use the motor as a sensor! We asked PER ZELLMAN of Emotron to explain In recent years, the development of frequency inverters has moved at a rapid pace. Terms like vector modulation, vector control, field-oriented control and direct torque control have been [...]

Original article date: November 1997 Linear Drives has doubled the performance of its distinctive tubular linear motors. High-Peter Kelly, Chief Executive of Linear Drives and the inventor of the original tubular linear motor, explains what this means in practice. The direct thrust electric linear drive is used to construct the new LD range of linear [...]

Original article date: November 1998 Electric motors are required to run more quietly and smoothly. Several techniques can be applied in combination to meet the objective. Tony Cuff of NSK-RHP explains. As electric motors function at increasingly higher speeds and higher operating temperatures selecting the right bearings is crucial to ensuring long life. However this [...]

Original article date: May 2000 PM-driven dynamometers to 300kWAndy Gardner of Meiden Europe explains why permanent magnets keep the heat down in dynamometers – and why it’s a good thing. Permanent magnet motors are now being used by Meidensha Corporation for a new range of dynamometers with continuous ratings up to 300kW that eliminates gears, [...]

Original article date: June 1999 Emotron launched the MSF range of soft starters to coincide with the industry fair at Hanover. A new starting method means that mechanical and electrical stresses can be significantly reduced Soft starters are used for gentle starting and stopping of induction motors. Pumps compressors mills fans and saws are applications [...]

Original article date: October 1998 Three-phase induction moors can be braked mechanically or electrically. This article from Siemens describes the methods available for electrical braking. All methods of electrical braking are based on the retarding force exerted on a conductor moving in as magnetic field and carrying induced current. There is no reliance on friction [...]

This article was originally written in the period 1995-2000 Energy-efficient motors cost more than the standard, so can they always be usually justified on a payback basis? This advice from Allen-Bradley. All major manufacturers produce both standard motors and high efficiency motors. Although energy-efficient motors cost more than the standard line, they are usually justified [...]

Original article date: November 1998 Choosing an electric motor and gearbox would appear simple until you appreciate there are more than 100 million possible combinations of motor and frame coupled with a variety of gearboxes. The best starting point is probably to look at the chosen application and to examine three different basic motor types [...]

Original article date: June 2000 You can do your bit towards cutting greenhouse gases by employing energy saving variable speed drives and high efficiency AC motors, says ABB’s JAMES HAIGH You’ve probably noticed that energy saving is back on the agenda. Big time. Government initiatives at the Rio Summit and the Kyoto Protocol are aimed [...]

Original article date: February 2000 Does it make any difference if a stepper driver uses digital signal processing (DSP)? GEOFF SORE from Smartdrive explains why he believes that it gives many advantages Using digital signal processing (DSP) technology for digital stepper-motor control offers a number of advantages to the machine builder and the end-user, but [...]