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
Transformers
Transformers Are Never Silent
Yes, we all know that transformers are never silent. This is actually quite impossible, but in an environmentally aware, highly regulated world, the issue is not the level of noise,… Read more
Oct 29, 2012 | By Edvard
Cables
Short Overview of LV Cable Terminations
A termination is the electrical and physical connection of a cable end to a piece of equipment or another cable. A splice is the electrical connection of a cable end to… Read more
Oct 27, 2012 | By Edvard
Electric Motor
Industrial Applications of Brushless Servomotor
A synchronous machine with permanent magnets on the rotor is the heart of the modern brushless servomotor drive. The motor stays in synchronism with the frequency of supply, though there… Read more
Oct 26, 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
Transformers
Definitions of Voltage Transformer Parameters
Rated voltage factor Rated primary voltage (Up) Rated secondary voltage Accuracy power Accuracy class Voltage ratio error Phase or phase displacement error Rated thermal limiting output The voltage transformer must… Read more
Oct 18, 2012 | By Edvard
High Voltage
Gas-Insulated Transmission Line (GIL) System Design
GIL systems are based on the successful SF6 tubular conductor technology, which has been around for several decades. GIL consist of a central aluminum conductor with a typical electrical cross… Read more
Oct 17, 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
Transformers
Heating of the Dry-type Transformer
Although transformers can be classified by core construction (shell or core type), the more functional types of standardized classifications are based on how the transformer is designed for its specific… Read more
Oct 15, 2012 | By Edvard
