5 steps to choose the best motor for your application
For line-operated motors, loads fall into three general categories: constant torque, torque that changes abruptly, and torque that change gradually over time. Bulk material conveyors, extruders, positive displacement pumps, and compressors without air unloaders run at relatively steady levels of… Read more
Dec 03, 2011 | By Edvard Csanyi
Guideline to Design Electrical Network for Building (Small Area)
Find out built up area in Sqft.of per flat per House/Dwelling unit. Multiply area in Sqft. by Load/Sqft according to following table: Type of Load Load/Sqft Industrial 100 Watt/Sqft Commercial 30 Watt/Sqft Domestic 15 Watt/Sqft Apply the diversity factor and… Read more
Dec 02, 2011 | By Jignesh Parmar
Transient Voltage Surge Suppressors
Transient Voltage Surge Suppressor (TVSS) is a device that every data center or mission critical facility should have. Why should every data center have one and what does it do you ask? The purpose of a TVSS is to eliminate… Read more
Dec 01, 2011 | By Edvard Csanyi
Overvoltages Caused by Direct Lightning Strokes
A lightning stroke is defined as a direct stroke if it hits either the tower or the shield wire or the phase conductor. This is illustrated in Figure 1. When the insulator string at a tower flashes over by direct… Read more
Nov 29, 2011 | By Edvard Csanyi
Fire Properties Of Cables
This is an area of increasing public and legislative concern, and therefore of increasing interest to engineers. There have been major advances in the fire performance of cables in recent years, and table below lists some of the relevant standards…. Read more
Nov 21, 2011 | By Edvard Csanyi
Partial Discharge Testing On Power Cable Systems
Partial discharge measurement is an important method of assessing the quality of the insulation of power cable systems, particularly for extruded insulation materials. This article considers partial discharge from two points of view: the measurement of all partial discharges occurring… Read more
Nov 18, 2011 | By Edvard Csanyi
Energy Demand Factor, Diversity Factor, Utilization Factor, and Load Factor
This technical article duscusses the five most important factors that are employed in the energy management: Demand Factor, Diversity Factor, Load Factor, Utilization Factor, and Coincidence Factor. The management of energy demand requires the efficient utilization of energy resources, the… Read more
Nov 14, 2011 | By Jignesh Parmar
Moving Iron Instruments – Voltmeter and Ammeter
Moving-iron instruments are generally used to measure alternating voltages and currents. In moving-iron instruments the movable system consists of one or more pieces of specially-shaped soft iron, which are so pivoted as to be acted upon by the magnetic field… Read more
Nov 13, 2011 | By Bipul Raman
Installation of Distribution-to-Utilization Voltage Transformers
Aerial transformer installations may utilize a three-phase unit or banked single-phase units. Transformers, either singly or in banks, having an individual unit or combined capacity greater than 300 kVA will not be mounted on single wood poles. Special structural considerations… Read more
Nov 11, 2011 | By Edvard Csanyi
Medium voltage circuit breaker operating sequence
Rated switching sequence according to IEC, O – t – CO – t’ – CO. (cf. opposite diagram): O – Represents opening operation CO – Represents closing operation followed immediately by an opening operation Slow: O – 3 min –… Read more
Nov 10, 2011 | By Edvard Csanyi
Working Principle of Earth Leakage Circuit Breaker (ELCB) and Residual Current Device (RCD)
The operation of an earth leakage circuit breaker (or shorten ELCB) is based on the fact that the algebraic sum of the currents in any healthy single phase, three phase and three phase and neutral system is zero. This simply… Read more
Nov 07, 2011 | By Jignesh Parmar
DC motor and generator – design, application and operation
History will recognize the vital role played by DC motors in the development of industrial power transmission systems, the dc machine being the first practical device to convert electrical power into mechanical power. Inherently straight forward operating characteristics, flexible performance… Read more
Nov 06, 2011 | By Edvard Csanyi
The Importance of the Correct PPE
Whilst awareness of the dangers of arc flash has continued to increase over the last few years, the number of incidents that are still occurring on a daily basis are shockingly high. Arc flash incidents are the greatest threat to… Read more
Oct 29, 2011 | By cgoulds
What is the difference between MCB, MCCB, ELCB, and RCCB
This technical article briefly describes the most common breaker-related protection devices in low-voltage applications: MCB, MCCB, ELCB, and RCCB. We’ll describe their main characteristics and limitations and try to solve some misunderstandings and differences that many young engineers mix up…. Read more
Oct 25, 2011 | By Jignesh Parmar
Aluminium or copper busbar trunking? Myth busted!
Following years of copper being the material of choice for high power busbar trunking in the UK, yet aluminium reigning supreme in the rest of the world, Schneider Electric takes a look at the case for aluminium over copper busbar… Read more
Oct 19, 2011 | By Edvard Csanyi
