Purpose of Disconnect Switches In HV Substation
Purpose of Disconnect Switches In HV Substation (on photo: Siemens Goab switch)Types and Characteristics Switches may be of several types, the common characteristic is that none are designed to...
View ArticleD.M.C.R. Protection Relay for Oil Transformer
DMCR - Detection, Measurement and Control Relay for Hermetically Sealed Oil TransformerContentIntroduction to D.M.C.R.Faults detected on live transformer unit:Dielectric fluid level is detected as...
View ArticleUnderground Residential Distribution Layouts
Underground Residential Distribution LayoutsUnderground ConstructionWhere general appearance, economics, congestion, or maintenance conditions make overhead construction inadvisable, underground...
View ArticlePower Measurement In a Three-Phase System
Power Measurement In a Three-Phase System (on photo: Traditional power meter)WattmeterElectrical power is measured with a wattmeter. A wattmeter consists of a current coil connected in series with...
View ArticleDifferences Between Earthed and Unearthed Cables
Differences Between Earthed and Unearthed CablesIntroductionIn HT electrical distribution, the system can be earthed or unearthed.The selection of unearthed or earthed cable depends on distribution...
View ArticleComparison of Protection Relay Types
Comparison of Protection Relay Types (photo by switchgearsupport.com) Comparison TableThis comparison summarize characteristics of all protection relay types described in previously published...
View ArticleHigh Voltage Substations Overview (part 1)
Substations and Distribution Substations Overview (Photo by Ipco Group)Introduction High voltage substations are interconnection points within the power transmission and distribution systems between...
View ArticleHigh Voltage Substations Overview (part 2)
High Voltage Substations Overview (part 2) Continued from first part: High Voltage Substations Overview (part 1) Distribution SubstationsTransformers are used for the transformation of high and medium...
View ArticleManipulating Energized Conductors With Hot Stick
Manipulating Energized Conductors With Hot Stick (photo by lineman.co.nz)Types of Hot SticksHot sticks are poles made of an insulating material.They have tools and/or fittings on the ends which allow...
View ArticleWhat is transformer rating based on?
What is transformer rating based on? (on photo: Transformer produced by Japanese transformer manufacturer Kitashiba Electric Co., Ltd.)Temperature & InsulationIn the U.S., transformers are rated...
View ArticleTypes and Applications Of Overcurrent Relay (part 1)
Types, applications and connections of Overcurrent relay (on photo: Transmission lines from Gillam to Churchill)Index Types of protection:Unit Type ProtectionNon-unit schemesOvercurrent...
View ArticleConnections Of Overcurrent Relay (part 2)
Connections Of Overcurrent Relay (part 2) Continued from first part: Types and Applications Of Overcurrent Relay (part 1) Connections of Overcurrent and Earth Fault Relays1. 3 Nos O/C relay for...
View ArticleHow to Monitor Wind Speed?
How to monitor wind speed? (Photo by: Andy @ Flickr)Wind Speed – Mistery Or Not?When considering wind power, most people ask what the average annual wind speed is and how to get that number. The usual...
View ArticleDid Tesla Discover the Secrets of Antigravity?
The first of four candid photos taken of Tesla at a press conference at the Hotel New Yorker July 10, 1935, his seventy-ninth birthday. Nikola Tesla has been credited for the creation of much of the...
View ArticleHow Motor Really Works?
Figure 1 - A motor action The basic working of a motor is based on the fact that when ‘a current carrying conductor is placed in a magnetic field, it experiences a force’.If you take a simple DC...
View ArticleHow Do We Define Hazardous Areas?
How Do We Define Hazardous Areas? (On photo: Flammable liquid warning)What is the hazardous area?The first requirement is to know what a hazardous area is. The principal factors relevant to the...
View ArticleMedium Voltage Switchgear (1) – Basics of Switching Devices
Medium Voltage Switchgear (1) – Basics of Switching DevicesIntroduction to Medium VoltageAccording to international rules, there are only two voltage levels:Low voltage: up to and including 1kV AC (or...
View ArticleMedium Voltage Switchgear (2) – Selection of Switching Devices
Medium Voltage Switchgear (2) – Selection of Switching Devices Continued from first part: Medium Voltage Switchgear (1) – Basics of Switching Devices 3. Selection of Switching Devices Switching...
View ArticleUsing High-Speed Grounding Switches
Using High-Speed Grounding Switches Automatic high-speed grounding switches are applied for protection of power transformers when the cost of supplying other protective equipment is deemed...
View ArticleDirect Starting Of Squirrel-Cage Induction Motors
Direct Starting Of Squirrel-Cage Induction MotorsIntroductionThe direct starting (Direct On Line, DOL) is the simplest and most cost-efficient method of starting a motor.This is assuming that the...
View Article