Switchgear
The apparatus used for switching, controlling and protecting the electrical circuits and equipment is known as switchgear. The term ‘switchgear’ is a generic term that includes a wide range of switching devices like circuit breakers, switches, switch fuse units, off-load isolators, HRC fuses, contactors, miniature circuit breakers, ELCBs, GFCIs etc.
Why Do We Use Transmission Switching in Electricity Supplies?
A transmission switching system is an essential component of the electricity supply network. It enables electricity transmission from one line to another for end users. It also helps ensure that
What is Switchgear? | Features, Components and Classification
What is Switchgear? Definition of Switchgear: The apparatus used for switching, controlling and protecting the electrical circuits and equipment is known as switchgear. The term ‘switchgear’ is a generic term
What are Protective Relays? | Types and Working
What is a Protective Relay? The protective relay was invented more than 160 years ago. During the last 60 years, it has undergone considerable change, the most obvious of which
Vacuum Circuit Breaker (VCB) – Principle, Construction and Working
What is VCB? VCB stands for Vacuum Circuit Breaker. In vacuum circuit breakers, the vacuum is used as the arc quenching medium. Vacuum offers the highest insulating strength. So it
Types of Electrical Relays
We have already discussed the working of electrical relays. Now we are going through different types of electrical relays. There are two basic classifications of relays: Electromechanical Relays Solid State
Type B Miniature Circuit Breaker ( Type B MCB)
A Type B MCB is a common type of miniature circuit breaker used to protect low power domestic circuits and residential application from overcurrent and short circuit faults. The MCB
Substation Earthing System Design
We have already given an introduction to substation earthing system in an article published earlier. Today we are going to discuss the design of substation earthing system. Before 1960s the
Substation Earthing System ( Grounding System ) – Earthing Mat
The substation earthing system comprises of a grid (earth mat) formed by a horizontal buried conductors. Read about design of substation earthing system here. The grounding system in substation is very
Substation Bus Configuration / Scheme: The Definitive Guide
In this article, you will learn different types of substation bus configuration and their application. The equipment and buses installed in the substation switchyard are arranged and connected in specific
Steam Power Stations – Arrangement and Working
Steam power stations convert the heat energy of coal combustion into electrical energy. A steam power station basically works on the Rankine cycle. Steam is produced in the boiler by utilizing
Solid State Relays (Static Relays)
What is a Static Relay? There are two basic classifications of relays – Electromechanical Relays and Solid State Relays (Static relay). One main difference between them is electromechanical relays have
Shackle insulator (Spool Insulator): Types, Construction & Working
Shackle insulators are one type of overhead insulator used to provide insulation to conductors on low voltage power lines. It is also known as a spool insulator or a butterfly
SF6 Circuit Breakers – Construction, Types and Working
In an SF6 Circuit breaker, sulphur hexafluoride gas is used as the arc quenching medium. The sulphur hexafluoride gas (SF6) is an electronegative gas and has a strong tendency to absorb
Sag in Overhead Transmission Lines
The difference in level between points of supports and the lowest point on the conductor is called sag in overhead transmission lines. Sag in Hot and Cold Day While erecting
Primary and Back-up Protection in Power System
Primary and Back-up Protection Primary protection (Main protection) is the essential protection provided for protecting an equivalent/machine or a part of the power system. As a precautionary measure, addition protection
Power Transformer Testing Methods – Type, Routine & Special Tests
An electrical power transformer has to go through a number of transformer testing procedures for confirming its specifications and performances. In this article, you will learn different types of transformer
Percentage Reactance in Power System (Transformer, Generator or Reactor)
Percentage reactance of power system elements such as generator, transformer and reactor are extensively used in short circuit calculation when any fault occurs in the system. Most faults in the
Parallel Operation of Single Phase Transformers
By parallel operation of single-phase transformers, we mean two or more transformers are connected to the same supply bus bars on the primary side and to a common bus bar/load on
Low Voltage Switchgear
As per IEC 60947, switchgears with rated voltages up to 1000 V ac and 1500 V dc are termed as low voltage switchgear. The term ‘switchgear’ is a generic term
Low Voltage Circuit Breakers – Design and Construction Basics
In this article, we are going to study the basics of low voltage circuit breaker design and construction. The operation and arc extinction of different types of circuit breakers were
Load Forecasting – Purpose, Classification and Procedure
What is Load Forecasting? Electrical energy cannot currently be stored in large amounts. It has to be generated whenever there is a demand for it. It is, therefore, imperative for
Introduction to Gas Turbine Power Plant
The gas turbine power plant obtains its power by utilizing the energy of burnt gases and air, which is at high temperature and pressure by expanding through several rings of
Introduction to Gas Insulated Substations / Switchgears (GIS)
Gas-insulated substations (GIS) have been used in power systems over the last three decades because of their high reliability, easy maintenance, small ground space requirement, etc. This article is an
Insulation Resistance Test (IR Test) or Megger Test
Insulation Resistance or IR Test is carried out by maintenance engineers to ensure the healthiness of the overall insulation system of electrical equipment. It reflects the presence or absence of
IEC 61850 – Substation Automation – Fundamentals
What is IEC 61850? IEC 61850 is a standard for the design of electrical substation automation. It is the base for all developments in substation automation. IEC 61850 is a
How RCCB/ELCB Protects You from Death?
Earthing does not guarantee that humans will be safe when they come into contact with live conductors. Although relays may be installed to detect earth leakages, typically their settings are
GFCI (Ground Fault Circuit Interrupter) – Working, Types, Installing and Troubleshooting
A ground fault circuit interrupter (GFCI or GFI) is an inexpensive electrical switchgear device that can either be installed in your electrical system or built into a power cord to protect
Function of Protective Relays in Power System
We usually think of an electric power system in terms of its more impressive parts – the big generating stations, transformers, high-voltage lines, etc. While these are some of the basic elements,
Disconnect Switches (Isolator) in Substation: Types, Design and Working
A disconnect switch is a mechanical device that conducts electrical current and provides an open point in a circuit for isolation of circuit breakers, circuit switchers, power transformers, capacitor banks,
Difference between Dielectric Testing & Insulation Resistance Measurement
All electrical installations and equipment comply with insulation resistance specifications so they can operate safely. Whether it involves the connection cables, the sectioning and protection equipment, or the motors and generators,