This document discusses electrical grounding and earthing systems. It begins by introducing grounding and earthing, and distinguishing between ground and neutral conductors. It then describes different types of earthing systems according to the IEC standard, including TN, TT, and IT networks. The document also covers different types of grounding used in radio communications, AC power installations, and lightning protection. It discusses the concept of virtual ground and multipoint grounding. Overall, the document provides an overview of electrical grounding and earthing systems, their uses, and important concepts.
What is Grounding?
• Importance of Grounding
• Types of Grounding
• Applications of Grounding in power system
• Instruments employed in Grounding
• Grounding procedure & calculations
• Hazards due to lack of Grounding
• Good Grounding practice
• IEEE rules regarding Grounding
• Conclusion
PPT on earthing, grounding and isolation made by the students of SVIT,Vasad under the valuable guidance of the faculties teaching us Electronics and Electrical workshop(EEW) under the course of GTU.
A switchgear or electrical switchgear is a generic term which includes all the switching devices associated with mainly power system protection. It also includes all devices associated with control, metering and regulating of electrical power system. Assembly of such devices in a logical manner forms a switchgear. This is the very basic definition of switchgear.
⋗To get more with details
https://www.youtube.com/channel/UC2SvKI7eepP241VLoui1D5A
The apparatus used for switching, controlling & protecting the electrical circuits & equipments are known as switchgear.
The switchgear equipments is essentially used with switching & interrupting currents either under normal or abnormal operating condition.
It consists of devices such as switches, fuses, circuit breakers, relays etc.
Basically every electric circuit needs a switching device & a protecting device.
What is Grounding?
• Importance of Grounding
• Types of Grounding
• Applications of Grounding in power system
• Instruments employed in Grounding
• Grounding procedure & calculations
• Hazards due to lack of Grounding
• Good Grounding practice
• IEEE rules regarding Grounding
• Conclusion
PPT on earthing, grounding and isolation made by the students of SVIT,Vasad under the valuable guidance of the faculties teaching us Electronics and Electrical workshop(EEW) under the course of GTU.
A switchgear or electrical switchgear is a generic term which includes all the switching devices associated with mainly power system protection. It also includes all devices associated with control, metering and regulating of electrical power system. Assembly of such devices in a logical manner forms a switchgear. This is the very basic definition of switchgear.
⋗To get more with details
https://www.youtube.com/channel/UC2SvKI7eepP241VLoui1D5A
The apparatus used for switching, controlling & protecting the electrical circuits & equipments are known as switchgear.
The switchgear equipments is essentially used with switching & interrupting currents either under normal or abnormal operating condition.
It consists of devices such as switches, fuses, circuit breakers, relays etc.
Basically every electric circuit needs a switching device & a protecting device.
Grounding or earthing offers two principal advantages. First, it provides protection to the power system. Secondly, earthing of electrical equipment ensures the safety of the persons handling the equipment.
In electrical engineering, a protective relay is a relay device designed to trip a circuit breaker when a fault is detected. The theory and application of these protective devices is an important part of the education of a power engineer who specializes in power system protection.
This presentation provides information about different types of protective relaying system.
Unit I: Introduction to Protection System:
Introduction to protection system and its elements, functions of protective relaying, protective zones, primary and backup protection, desirable qualities of protective relaying, basic terminology.
Relays:
Electromagnetic, attracted and induction type relays, thermal relay, gas actuated relay, design considerations of electromagnetic relay.
Unit-II: Relay Application and Characteristics:
Amplitude and phase comparators, over current relays, directional relays, distance relays, differential relay.
Static Relays: Comparison with electromagnetic relay, classification and their description, over current relays, directional relay, distance relays, differential relay.
Unit-III Protection of Transmission Line:
Over current protection, distance protection, pilot wire protection, carrier current protection, protection of bus, auto re-closing,
Unit-IV: Circuit Breaking:
Properties of arc, arc extinction theories, re-striking voltage transient, current chopping, resistance switching, capacitive current interruption, short line interruption, circuit breaker ratings.
Testing Of Circuit Breaker: Classification, testing station and equipments, testing procedure, direct and indirect testing.
Unit-V Apparatus Protection:
Protection of Transformer, generator and motor.
Circuit Breaker: Operating modes, selection of circuit breakers, constructional features and operation of Bulk Oil, Minimum Oil, Air Blast, SF6, Vacuum and d. c. circuit breakers.
FUNDAMENTALS OF POWER SYSTEM PROTECTION
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Electrical fault is the deviation of voltages and currents from nominal values or states. Under normal operating conditions, power system equipment or lines carry normal voltages and currents which results in a safer operation of the system.
How is power transformer protected??? This provides a basic understanding of power transformer. Furthermore, the protective relay application on power transformer is included.
To sense/detect the fault occurrence and other abnormal conditions at the protected equipment/area/section.
To operate the correct circuit breakers so as to disconnect only the faulty equipment/area/section as quickly as possible, thus minimizing the damage caused by the faults.
To operate the correct circuit breakers to isolate the faulty equipment/area/section from the healthy system in the case of abnormalities like overloads, unbalance, undervoltage, etc.
To clear the fault before the system becomes unstable.
To identify distinctly where the fault has occurred.
Practical Electrical Wiring Standards - National Rules for Electrical Install...Living Online
Internationally there has been steady progress towards the harmonisation of electrical wiring standards. European standards are based on the international IEC 364 under the umbrella of Harmonisation Document HD 384. The format of these is reflected in the ETCI national rules ET 101: 2008 and the UK IEE wiring regulations BS 7671:2008.
This workshop is designed to provide up to date information and training on the current edition of National Rules ET 101: 2008. It will consist of in-depth teaching on all aspects of the national rules and their application with many practical examples and sample design calculations. The workshop includes references to safety, maintenance, inspection and testing. In addition, it provides a summary of some of the basic principles necessary for a good understanding of electrical installation technology.
MORE INFORMATION: http://www.idc-online.com/content/practical-electrical-wiring-standards-national-rules-electrical-installations-et-1012008-2
Grounding or earthing offers two principal advantages. First, it provides protection to the power system. Secondly, earthing of electrical equipment ensures the safety of the persons handling the equipment.
In electrical engineering, a protective relay is a relay device designed to trip a circuit breaker when a fault is detected. The theory and application of these protective devices is an important part of the education of a power engineer who specializes in power system protection.
This presentation provides information about different types of protective relaying system.
Unit I: Introduction to Protection System:
Introduction to protection system and its elements, functions of protective relaying, protective zones, primary and backup protection, desirable qualities of protective relaying, basic terminology.
Relays:
Electromagnetic, attracted and induction type relays, thermal relay, gas actuated relay, design considerations of electromagnetic relay.
Unit-II: Relay Application and Characteristics:
Amplitude and phase comparators, over current relays, directional relays, distance relays, differential relay.
Static Relays: Comparison with electromagnetic relay, classification and their description, over current relays, directional relay, distance relays, differential relay.
Unit-III Protection of Transmission Line:
Over current protection, distance protection, pilot wire protection, carrier current protection, protection of bus, auto re-closing,
Unit-IV: Circuit Breaking:
Properties of arc, arc extinction theories, re-striking voltage transient, current chopping, resistance switching, capacitive current interruption, short line interruption, circuit breaker ratings.
Testing Of Circuit Breaker: Classification, testing station and equipments, testing procedure, direct and indirect testing.
Unit-V Apparatus Protection:
Protection of Transformer, generator and motor.
Circuit Breaker: Operating modes, selection of circuit breakers, constructional features and operation of Bulk Oil, Minimum Oil, Air Blast, SF6, Vacuum and d. c. circuit breakers.
FUNDAMENTALS OF POWER SYSTEM PROTECTION
FUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTIONFUNDAMENTALS OF POWER SYSTEM PROTECTION
Electrical fault is the deviation of voltages and currents from nominal values or states. Under normal operating conditions, power system equipment or lines carry normal voltages and currents which results in a safer operation of the system.
How is power transformer protected??? This provides a basic understanding of power transformer. Furthermore, the protective relay application on power transformer is included.
To sense/detect the fault occurrence and other abnormal conditions at the protected equipment/area/section.
To operate the correct circuit breakers so as to disconnect only the faulty equipment/area/section as quickly as possible, thus minimizing the damage caused by the faults.
To operate the correct circuit breakers to isolate the faulty equipment/area/section from the healthy system in the case of abnormalities like overloads, unbalance, undervoltage, etc.
To clear the fault before the system becomes unstable.
To identify distinctly where the fault has occurred.
Practical Electrical Wiring Standards - National Rules for Electrical Install...Living Online
Internationally there has been steady progress towards the harmonisation of electrical wiring standards. European standards are based on the international IEC 364 under the umbrella of Harmonisation Document HD 384. The format of these is reflected in the ETCI national rules ET 101: 2008 and the UK IEE wiring regulations BS 7671:2008.
This workshop is designed to provide up to date information and training on the current edition of National Rules ET 101: 2008. It will consist of in-depth teaching on all aspects of the national rules and their application with many practical examples and sample design calculations. The workshop includes references to safety, maintenance, inspection and testing. In addition, it provides a summary of some of the basic principles necessary for a good understanding of electrical installation technology.
MORE INFORMATION: http://www.idc-online.com/content/practical-electrical-wiring-standards-national-rules-electrical-installations-et-1012008-2
Practical HV and LV Switching Operations and Safety RulesLiving Online
In this workshop, we will take a look at the theoretical aspects of safety as well as the practical and statutory issues. One of the main causes of electrical accidents is said to be incorrect isolation of the circuits where work is to be done. To ensure safety of operators and maintenance personnel, proper switching procedures are necessary and more so when the circuits have multiple feeds and are complex. The possibility of voltage being fed back from secondary circuits needs to be considered as well. This workshop emphasises on the isolation procedures to ensure proper and safe isolation of HV, LV and secondary circuits.
Electrical safety is not just a technical issue. Accidents can only be prevented if appropriate safety procedures are evolved and enforced. This includes appropriate knowledge of equipment and systems imparted through systematic training to each and every person who operates or maintains the equipment. We will cover all these aspects in detail.
MORE INFORMATION: http://www.idc-online.com/content/practical-hv-and-lv-switching-operations-and-safety-rules-25
ppt of Three phase fault analysis with auto reset for temporary fault and tri...Vikram Rawani
it's the final ppt which we have made for the project hope you will like it and make use most of it. it will definitely help you guys .
all the best (Y) :)
It is necessary to take safety precautions at home since your kids might end up playing with electricity. Here are a few tips for electrical safety which you can share with your kids. Call Caddell Electric for further assistance. http://www.dallaselectricrepair.com/
SYSTEM NEUTRAL EARTHING
-DEFINITION OF SYSTEM EARTHING
-Comparative Performance For Various Conditions Using Different Earthing Methods
-EQUIPMENT SIZING
- APPENDIX FOR TYPICAL EARTHING TRANSFORMER SIZING
- APPENDIX GIVING GUIDELINE FOR SIZING OF COMMON BUS CONNECTED MEDIUM RESISTANCE EARTHING
Part one of a three part series covering grounding and its role in protecting personnel, equipment, and integrity of electrical signals. The first installment reviews circuit grounding and its importance, along with the use of earth ground in the US AC power system. Suitable for readers of all technical levels.
The complete 3-part series on best-practices for grounding electrical equipment produced by Acromag.
When wiring or connecting circuits, electrical equipment, and electrical instruments, there is a connection that you probably don’t give much thought to, and one that consequently reigns as one of the greatest sources of instrument error and malfunction. The connection is your connection to Ground.
Electrical systems must be grounded in order to work properly. The earth often serves as an ideal ground because of its large mass and ability to absorb charge, but ground can be any electrical connection that is able to freely conduct electricity, and grounding a circuit does not always refer to making a physical connection to earth ground.
How Earthing works. What is earthing all in one for students and others? Types of Earthing. description that is needed. You can get to know how important Earthing is.
This application note discusses practical design of earthing electrodes, including the calculation of earthing resistance for various electrode configurations, the materials used for electrodes and their corrosion performance. Equations are given for many common electrode geometries, including horizontal strips, rods, meshes, cable screens and foundations.
Despite the fact that these formulae are derived under the false assumption that soil is boundless and homogenous and ignore the fact that the ground resistivity changes with moisture content, the values obtained, although approximate, are useful in predicting and optimising performance.
Green computing is the environmentally responsible and eco-friendly use of computers and their resources. In broader terms, it is also defined as the study of designing, manufacturing/engineering, using and disposing of computing devices in a way that reduces their environmental impact.
Cloud computing is a type of Internet-based computing that provides shared computer processing resources and data to computers and other devices on demand. It is a model for enabling ubiquitous, on-demand access to a shared pool of configurable computing resources (e.g., computer networks, servers, storage, applications and services),
Cloud computing is a type of Internet-based computing that provides shared computer processing resources and data to computers and other devices on demand. It is a model for enabling ubiquitous, on-demand access to a shared pool of configurable computing resources (e.g., computer networks, servers, storage, applications and services),
Artificial intelligence (AI) is intelligence exhibited by machines. In computer science, the field of AI research defines itself as the study of "intelligent agents". Robotics is the interdisciplinary branch of engineering and science that includes mechanical engineering, electrical engineering, computer science, and others.
Artificial intelligence (AI) is intelligence exhibited by machines. In computer science, the field of AI research defines itself as the study of "intelligent agents".
Robotics is the interdisciplinary branch of engineering and science that includes mechanical engineering, electrical engineering, computer science, and others. Robotics deals with the design, construction, operation, and use of robots,[1] as well as computer systems for their control, sensory feedback, and information processing.
Light Fidelity (Li-Fi) is a bidirectional, high-speed and fully networked wireless communication technology similar to Wi-Fi. The term was coined by Harald Haas[1] and is a form of visible light communication and a subset of optical wireless communications (OWC) and could be a complement to RF communication (Wi-Fi or cellular networks), or even a replacement in contexts of data broadcasting.
1. ELECTRICAL GROUNDING AND
EARTHING SYSTEMS
Presented By:
T.Sidharth Sankar Achary
Regd No-1021106019
7th sem.
Electrical Engg.
2. CONTENTS
INTRODUCTION.
DIFFERENCE BETWEEN GROUND AND NEUTRAL.
TYPES OF EARTHING SYSTEMS.
TYPES OF GROUNDING.
USES.
CONCEPT OF VIRTUAL GROUND.
MULTIPOINT GROUND.
CONCLUSION.
REFERENCES.
3. INTRODUCTION
In electricity supply systems, an earthing system defines the
electrical potential of the conductors relative to that of the
Earth's conductive surface.
The choice of earthing system has implications for the safety and
electromagnetic compatibility of the power supply.
A protective earth (PE) connection ensures that all exposed
conductive surfaces are at the same electrical potential as the
surface of the Earth, to avoid the risk of electrical shock if a
person touches a device in which an insulation fault has
occurred. It also ensures that in the case of an insulation fault, a
high fault current flows, which will trigger an over current
protection device (fuse, MCB) that disconnects the power
supply.
A functional earth connection serves a purpose other than
providing protection against electrical shock.
4. DIFFERENCE BETWEEN
GROUND AND NEUTRAL.
Ground or earth in a mains (AC power) electrical wiring system
is a conductor that exists primarily to help protect against faults
and which in normal operation does not carry current.
Neutral is a circuit conductor that may carry current in normal
operation, and which is usually connected to earth. In house
wiring, it is the center tap connection of the secondary winding
of the power company's transformer.
In a polyphase or three-wire AC system, the neutral conductor is
intended to have similar voltages to each of the other circuit
conductors, and similar phase spacing. By this definition, a
circuit must have at least three wires for one to serve as a neutral.
In the electrical trade, the conductor of a 2-wire circuit that is
connected to the supply neutral point and earth ground is also
referred to as the "neutral". This is formally described in the US
and Canadian electrical codes as the "identified" circuit
conductor.
5. TYPES OF EARTHING SYSTEMS
International standard IEC 60364 distinguishes three families of
earthing arrangements, using the two-letter codes TN, TT, and
IT.
The first letter indicates the connection between earth and the
power-supply equipment (generator or transformer):
T : direct connection of a point with earth (French: terre);
I : no point is connected with earth (isolation), except perhaps
via a high impedance.
The second letter indicates the connection between earth and the
electrical device being supplied:
T : direct connection with earth, independent of any other earth
connection in the supply system;
N : connection to earth via the supply network.
12. TYPES OF GROUNDING
In radio frequency communications
In AC power wiring installations
Circuit ground versus earth.
In lightning protection
13. In radio frequency communications
An electrical connection to earth for as a reference potential for
radio frequency antenna signals.
High frequency signals can flow to earth through capacitance,
capacitance to ground is an important factor in effectiveness of
signal grounds.
An ideal signal ground maintains zero voltage regardless of how
much electrical current flows into ground or out of ground.
The resistance at the signal frequency of the electrode-to-earth
connection determines its quality, and that quality is improved by
increasing the surface area of the electrode in contact with the
earth, increasing the depth to which it is driven, using several
connected ground rods, increasing the moisture of the soil,
improving the conductive mineral content of the soil, and
increasing the land area covered by the ground system.
14. In AC power wiring installations
In a mains (AC power) wiring installation, the ground is a wire
with an electrical connection to earth, that provides an alternative
path to the ground for heavy currents that might otherwise flow
through a victim of electric shock.
These may be located locally, be far away in the suppliers
network or in many cases both.
This grounding wire is usually but not always connected to the
neutral wire at some point.
The ground wire is also usually bonded to pipe work to keep it
at the same potential as the electrical ground during a fault.
Water supply pipes often used to be used as ground electrodes
but this was banned in some countries when plastic pipe such as
PVC became popular.
This type of ground applies to radio antennas and to lightning
protection systems.
15. Circuit ground versus earth
In an electrical circuit operating at signal voltages (usually less
than 50 V or so), a common return path that is the zero voltage
reference level for the equipment or system.
Voltage is a differential quantity, which appears between two
points having some electrical potentials. In order to deal only
with a voltage (an electrical potential) of a single point, the
second point has to be connected to a reference point (ground)
having usually zero voltage.
This signal ground may or may not actually be connected to a
power ground.
A system where the system ground is not actually connected to
earth is often referred to as a floating ground.
16. In lightning protection
A ground conductor on a lightning protection system is used to
dissipate the strike into the earth.
17. USES
A power ground serves to provide a return path for fault
currents and therefore allow the fuse or breaker to disconnect
the circuit.
Filters also connect to the power ground, but this is mainly to
stop the power ground carrying noise into the systems which the
filters protect, rather than as a direct use of the power ground.
In Single Wire Earth Return (SWER) electrical distribution
systems, costs are saved by using just a single high voltage
conductor for the power grid. This system is mostly used in
rural areas where large earth currents will not otherwise cause
hazards.
Signal grounds serve as return paths for signals and power at low
voltages (less than about 50 V) within equipment, and on the
signal interconnections between equipment.
20. VIRTUAL GROUND CONCEPT
If two opposite power sources are connected each other by a
conductive medium so that their opposite output quantities are
superposed (summed), zero or reference level result referred to
as virtual ground appears somewhere along the medium.
In this "conflict" point, the efforts of the "fighting" sources are
"neutralized". The process is associated with continuous energy
wasting from both the sources as a result of a continuous energy
flow through the medium.
Shortly, virtual ground phenomenon is summing of opposite
equal quantities associated with continuous energy wasting;
virtual ground represents the result of summing two opposite
equal quantities.
21. MULTI POINT GROUND
A Multipoint Ground is an alternate type of electrical installation
that attempts to solve the Ground Loop and Mains hum
problem by creating many alternate paths for electrical energy to
find its way back to ground.
The distinguishing characteristic of a multipoint ground is the
use of many interconnected grounding conductors into a loose
grid configuration.
There will be many paths between any two points in a
multipoint grounding system, rather than the single path found
in a star topology ground.
22. CONCLUSION
Grounding and Earthing systems form the first line
of defense in every type of electrical systems. The
system may be a generator/transformer/housing
installation/generating station/etc. So it is strictly
advised to know the basic concepts of grounding as
far as electrical engg. is concerned.