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… Read more
Jul 19, 2012 | By Edvard Csanyi

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… Read more
Jul 14, 2012 | By Edvard Csanyi

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… Read more
Jun 16, 2012 | By Edvard Csanyi

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…. Read more
Jun 13, 2012 | By Edvard Csanyi

Direct On Line (DOL) Motor Starter
Different starting methods are employed for starting induction motors because Induction Motor draws more starting current during starting. To prevent damage to the windings due to the high starting current… Read more
Apr 22, 2012 | By jiguparmar

Star-delta motor starter explained in details
Most induction motors are started directly on line, but when very large motors are started that way, they cause a disturbance of voltage on the supply lines due to large… Read more
Apr 10, 2012 | By jiguparmar

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,… Read more
Apr 05, 2012 | By Edvard Csanyi

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… Read more
Feb 29, 2012 | By Edvard Csanyi

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… Read more
Feb 03, 2012 | By Edvard Csanyi

Three phase induction motors – Operating principle
An electric motor converts electrical energy into a mechanical energy which is then supplied to different types of loads. A.c. motors operate on an a.c. supply, and they are classified… Read more
Feb 03, 2012 | By Henry James

Synchronous Motor Construction
Synchronous motors convert electrical power to mechanical power and synchronous generators convert mechanical power to electrical power; and synchronous condensers supply only reactive power to stabilize system voltages. Synchronous motors, generators, and… Read more
Jan 14, 2012 | By Edvard Csanyi

How to select AC converter for VSD?
Altough manufacturers’ catalogues try to make it easy as possible, there are many variables associated with the selection and rating of the optimum electric motor and AC converter for a… Read more
Jan 06, 2012 | By Edvard Csanyi

NEC Code for Size of Cable for Motor
Size of Cable for Branch circuit which has Single Motor connection is 125% of Motor Full Load Current Capacity. What is the minimum rating in amperes for Cables supplying 1… Read more
Dec 30, 2011 | By jiguparmar

The Cage Induction Motor Explained In Details
This simplest form of AC induction motor or asynchronous motor is the basic, universal workhorse of industry. Its general construction is shown in Fig. 1. It is usually designed for… Read more
Dec 29, 2011 | By Edvard Csanyi

Motor starting problem and high motor inrush currents
Electric motor protection device depends on the accurate and correct selection of overload(s), fuses and/or circuit breakers. Over the years the protective devices have been selected according to the applicable… Read more
Dec 23, 2011 | By Edvard Csanyi
