Electric Motor
Motors for Hazardous Areas
Electrical drives/motors that are operated in hazardous areas must be built and engineered so that they cannot become an ignition source. This applies not only to normal operating and starting, but also… Read more
Nov 02, 2012 | By Edvard
Energy and Power
Application of 4-pole Switchgear Devices
The majority of low-voltage switchgear is equipped with three contacts in the main circuit, which switch three-phase loads in all poles. In some applications switchgear with four main poles is… Read more
Oct 31, 2012 | By Edvard
Energy and Power
Smart and safe protective shutdown of LV system with selectivity
From the point of view of the operational safety and reliability of an entire low-voltage installation, it is usually desirable to specifically isolate the part of a system affected by… Read more
Oct 30, 2012 | By Edvard
Cables
Corrosion Types Encountered With Power Cables
Introduction Anodic Corrosion (Stray DC Currents) Cathodic Corrosion Galvanic Corrosion Chemical Corrosion AC Corrosion Local Cell Corrosion Other Forms of Corrosion There are numerous types of corrosion, but the ones… Read more
Oct 25, 2012 | By Edvard
Energy and Power
Safety Clearance Recommendations for Transformer
Clearance from Outdoor Liquid Insulated Transformers to Buildings (NEC) Clearance between Two Outdoor Liquid Insulated Transformers (NEC) Dry Type Transformer in Indoor Installation (NES 420.21) Dry Type Transformer in Outdoor… Read more
Oct 24, 2012 | By jiguparmar
Cables
The Good, The Bad and The Ugly Cable Insulation
The fundamental understanding of cable insulation properties forms the foundation for assessment of cable operability. These same fundamentals provide the basis for evaluating whether various electrical and physical tests and… Read more
Oct 23, 2012 | By Edvard
Cables
Cable engineering in substations and power plants
Is it true that single core cable should be unarmored because eddy currents are induced in armor of single core cable which will cause additional losses? If true then why… Read more
Oct 22, 2012 | By Asif Eqbal
Electric Motor
Few Words About Three-Phase Alternator
The three-phase alternator, as the name implies, has three single-phase windings spaced such that the voltage induced in any one phase is displaced by 120º from the other two. A… Read more
Oct 20, 2012 | By Edvard
Energy and Power
Testing and Commissioning of Current Transformer
1. Objective 2. Test Equipment Required 3. Test procedures Mechanical Check and Visual Inspection Insulation Resistance Test Polarity Test Secondary/Loop Resistance Test Burden Test (optional test) Magnetization Curve Test (optional… Read more
Oct 19, 2012 | By Edvard
Energy and Power
Simplify Downstream Installation with Cascading
Cascading provides circuit breakers placed downstream of a limiting circuit breaker with an enhanced breaking capacity. The limiting circuit breaker helps the circuit breaker placed downstream by limiting high short-circuit… Read more
Oct 16, 2012 | By Edvard
Energy and Power
NEC Requirements for Emergency Systems
Emergency systems are generally installed in buildings that are or can be occupied by 1000 or more persons or are more than 75 ft high. These are buildings where artificial… Read more
Oct 12, 2012 | By Edvard
Energy and Power
Safety Clearance Recommendations for Electrical Panel
Working Space around Indoor Panel/Circuit Board (NES 312.2) Clearance around an Indoor electrical panel (NEC 110.26) Clearance for Conductor Entering in Panel (NES 408.5) Clearance between Bare Metal Busbar in… Read more
Oct 10, 2012 | By jiguparmar
Energy and Power
Fire-Fighting Precautions in Power Substation
The layout of the plant and the design of the building play a major part in reducing the spread of fire and the effect of explosions. For example, equipment and… Read more
Oct 09, 2012 | By Edvard
Energy and Power
Disturbances In LV Networks Due To Surges
There are two types of surge: those generated by a lightning impact and those resulting from electrical switchgear switching operations. Surges resulting from lightning strokes (see figure below) can affect… Read more
Oct 06, 2012 | By Edvard
Energy and Power
How to Protect Capacitor Banks?
Capacitor banks are used to compensate for reactive energy absorbed by electrical system loads, and sometimes to make up filters to reduce harmonic voltage. Their role is to improve the… Read more
Oct 05, 2012 | By Edvard
