Electric Motor
Motor protection depending on size and voltage level
Motor protections vary widely depending on the size of the motor and voltage level involved, thus only the more common ones are discussed in this technical article. Index Motor Instantaneous Over-current Protection Motor Timed Over-Current Protection Thermal OverLoad Motor Ground… Read more
Aug 30, 2012 | By Edvard Csanyi
Electric Motor
Basics of 3-phase Induction Motor (part 4)
When a motor is expected to operate in unfavorable conditions such as: Intermittent overloading Higher ambient temperatures A restricted temperature rise as for a spinning mill, A refinery or a hazardous area Frequent starts, stops and reverses or any such… Read more
Aug 07, 2012 | By Asif Eqbal
Electric Motor
Basics of 3-phase Induction Motor (part 3)
Continued fro second part – Basics of 3-phase Induction Motor (part 2) Technical data to be specified by purchaser before purchasing a 3 phase induction motor: No. Technical data to be specified Data 1. General data about ambient temperature and… Read more
Aug 03, 2012 | By Asif Eqbal
Electric Motor
Basics of 3-phase Induction Motor (part 2)
Continued from first part – Basics of 3-phase Induction Motor (part 1) For the purpose of standardization, the preferred rated voltages of three phase induction motor shall be in accordance with IS 12360: 1988. The voltages for three phases, 50… Read more
Aug 02, 2012 | By Asif Eqbal
Electric Motor
Basics of 3-phase Induction Motor (part 1)
This article will deal with those concepts of 3 phase induction motor which are essential prerequisite for proper selection, procurement, installation and maintenance of the same. Before any actual discussion on motor is started It will better to have a… Read more
Aug 01, 2012 | By Asif Eqbal
Electric Motor
AC Adjustable Speed Drive (ASD) – An Overview
The simplest and least expensive way to control the speed of a process or piece of equipment is to operate all the equipment at full speed. Many applications require the speed of a process or piece of equipment to be… Read more
Jul 19, 2012 | By Edvard Csanyi
Electric Motor
Thermal (Overload) Motor Relay Protection
The majority of winding failures in motor are either indirectly or directly caused by overloading (either prolonged or cyclic), operation on unbalanced supply voltage, or single phasing, which all lead through excessive heating to the deterioration of the winding insulation… Read more
Jul 14, 2012 | By Edvard Csanyi
Electric Motor
Soft Starter In Industrial Applications
An induction motor connected directly to the power supply draws a constant magnetizing current at full speed, no matter what the load is. At anything less than full load, power factor of the induction motor is less than its rated… Read more
Jun 16, 2012 | By Edvard Csanyi
Electric Motor
Advantages of Variable Speed Motors
Most motors are designed to operate at a constant speed and provide a constant output. While in many cases this may be more than adequate, it is not in all. Two-speed induction motors can improve efficiency for refrigerators, air conditioners,… Read more
Jun 13, 2012 | By Edvard Csanyi
Electric Motor
Measurement of insulation resistance (IR) – Part 2
This article goes into details of insulation resistance values measured by Megger tester on many different kinds of equipment, such as switchgear, electrical wires & cables, electric motors, transmission & distribution lines, and other power system equipment. An insulation tester… Read more
Apr 29, 2012 | By Jignesh Parmar
Electric Motor
Direct On Line (DOL) Motor Starter
Different starting methods are employed for starting induction motors because Induction Motor draws more starting current during starting. We use a variety of starters in order to protect the windings from being damaged by the high current flow that is… Read more
Apr 22, 2012 | By Jignesh Parmar
Electric Motor
Star-delta motor starter explained in details
Where is Star-Delta motor starter used? Well, the majority of induction motors are started directly on line (DOL), but when very big motors are started in this manner, the large starting current surges produce a disruption in the voltage on… Read more
Apr 10, 2012 | By Jignesh Parmar
Electric Motor
The direct current (DC) motor – Principle of operation
DC motors have been used in industrial applications for years. Coupled with a DC drive, DC motors provide very precise control DC motors can be used with conveyors, elevators, extruders, marine applications, material handling, paper, plastics, rubber, steel, and textile… Read more
Apr 05, 2012 | By Edvard Csanyi
Electric Motor
Why do we find electric motor drive very important?
Electric motors impact almost every aspect of modern living. Refrigerators, vacuum cleaners, air conditioners, fans, computer hard drives, automatic car windows, and multitudes of other appliances and devices all use electric motors to convert electrical energy into useful mechanical energy…. Read more
Feb 29, 2012 | By Edvard Csanyi
Electric Motor
Internal losses that reduce efficiency of a DC generator
There are four internal losses that contribute to lower efficiency of a DC generator. Copper losses Eddy-current losses Hysteresis losses Mechanical losses Copper loss is the power lost as heat in the windings; it is caused by the flow of… Read more
Feb 03, 2012 | By Edvard Csanyi
