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VOLTAGE CONTROLLER,

VOLTAGE CONTROLLER,



Voltage fluctuation is a common phenomenon in every part of the country. The industrial units running round the clock usually face the problem of low and high voltage. 90% of industrial load is of motors. Electric motors draw considerably high current at low & high voltage. This higher current affects the electrical motors (particularly smaller capacity motors up to 7.5 H.P.) in three ways.

Higher current produces higher losses in electrical motors which causes premature failure of winding
These higher losses of electric motors also increase the losses of cables, switches, transformers and other associated equipment
For smooth continuous operation of motors, overload relays are usually set at 20% higher setting.


Automatic Voltage Controller is the most efficient equipment used to tackle this problem. We are one of the principal Industrial Automatic Voltage Controller Suppliers in India. Servo Controlled Automatic Voltage Controller that we offer has various advantages that help in saving a lot on electricity bill.

Advantages
Reduction in Breakdown of Electrical Equipment
Energy Saving
Improvement in Power Factor
Reduction in MDI
Uniform Quality of End Product
80% Depreciation as per Income Tax Act

Payback Period

Owing to its high efficiency and associated benefits, the payback period for the cost of Servo Voltage Stabilizer is from 6-12 months depending upon the input voltage variation and number of working hours of the plant. The HIGHER the input voltage the SHORTER will be the payback period.

Description of Automatic Voltage Controller
Servo Stabilizer primarily consists of the following

Linear Type Plus/Minus type Vertical Rolling Contact type Regulator
Double Wound Buck/Boost Transformer
Electronic Control Circuit and meter panel.


The regulator and buck boost transformer are oil cooled, housed in same or separate steel tanks. Radiators, if necessary are provided for effective cooling. Their core is built from grain oriented silicon steel Laminations which keep losses to the minimum and they are wound with electrolytic grade copper to minimize the losses, vacuum impregnated and oven dried as per IS. Attention for Power Consumer Units Having L.T. Connections but Not Having Their Own Distribution Transformer and situated in Commercial / residential Areas.

It has been observed that the said power consumers usually face unbalanced input voltage problem and to overcome the same should install Automatic Voltage Controller suitable for unbalanced input voltage (individual phase control).

Solar Street Lighting System

Solar Street Lighting System

Home › Products › Solar Street Lighting System






We present the finest range of Solar Street Lighting System in the market. We are considered as one of the ace Street Lighting System Suppliers in Kanpur, UP. Solar Home Lighting System offered by us provides free, renewable energy in the home with every flick of a light switch. Solar lighting can aid with this by reducing reliance on fossil fuels and the electrical grid. In addition to this, it works to save the environment as well. The use of Solar Street Lighting System is a cost effective choice.

Application Areas
Street Lighting / Highway Lighting / Bridge Lighting purposes
Park Lighting & Garden Lighting purposes


Size & Quality
Octagonal/polygonal galvanized pole from 9meter to 12 meter on wind test of 180km per hour.

ELECTRICAL GROUNDI ANDEARTHING SYSTEMS

ELECTRICAL GROUNDI  ANDEARTHING  SYSTEMS





Electrical grounding and earthing systems
Presentation Transcript
ELECTRICAL GROUNDING AND EARTHING SYSTEMS Presented By: T.Sidharth Sankar Achary Regd No-1021106019 7th sem. Electrical Engg.
CONTENTS INTRODUCTION. DIFFERENCE BETWEEN GROUND AND NEUTRAL. TYPES OF EARTHING SYSTEMS. TYPES OF GROUNDING. USES. CONCEPT OF VIRTUAL GROUND. MULTIPOINT GROUND. CONCLUSION. REFERENCES.
INTRODUCTION In electricity supply systems, an earthing system defines the electrical potential of the conductors relative to that of the Earths 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.
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 companys 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.
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.
TN NETWORK
TN-S NETWORK
TN-C NETWORK
TN-C-S NETWORK
TT NETWORK
IT NETWORK
TYPES OF GROUNDING In radio frequency communications In AC power wiring installations Circuit ground versus earth. In lightning protection
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.
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.
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.
In lightning protection A ground conductor on a lightning protection system is used to dissipate the strike into the earth.
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.
GENERAL GROUNDING
GENERATOR EARTHING
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.
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.
CONCLUSIONGrounding and Earthing systems form the first lineof defense in every type of electrical systems. Thesystem may be a generator/transformer/housinginstallation/generating station/etc. So it is strictlyadvised to know the basic concepts of grounding asfar as electrical engg. is concerned.

EARTHING SYSTEM

EARTHING   SYSTEMS



TT SYSTEM

A TT system has a direct connection to the supply source to earth and a direct connection of the installation metalwork to earth. An example is an overhead line supply with earth electrodes, and the mass of earth as a return path as shown below.


Note that only single-phase systems have been shown for simplicity.



TN-S SYSTEM

A TN-S system has the supply source directly connected to earth, the installation metalwork connected to the neutral of the supply source via the lead sheath of the supply cable, and the neutral and protective conductors throughout the whole system performing separate functions.





The resistance around the loop P-B-N-E should be no more than 0.8 ohms.





TN-C-S SYSTEM

A TN-C-S system is as the TN-S but the supply cable sheath is also the neutral, i.e. it forms a combined earth/neutral conductor known as a PEN (protective earthed neutral) conductor.

The installation earth and neutral are separate conductors.

This system is also known as PME (protective multiple earthing).



The resistance around the P-B-N-N loop should be less than 0.35 ohms.



SUMMARY OF EARTHING SYSTEMS



The TT method is used mostly in country areas with overhead transmission lines. In contrast to the TN-S system there is no metallic path from the consumer's terminals back to the sub-station transformer secondary windings. Because the earth path may be of high resistance, a residual current circuit-breaker (R.C.C.B.) is often fitted so that if a fault current flows in the earth path then a trip disconnects the phase supply.

For protection against indirect contact in domestic premises, every socket outlet requires an RCCB with a maximum rated current of 30mA.



The TN-S system of wiring uses the incoming cable sheath as the earth return path and the phase and neutral have separate conductors. The neutral is then connected to earth back at the transformer sub-station.

Remember in TN-S, the T stands for earth (terre), N for neutral and S denotes that the protective (earth) and neutral conductors are separate.



The TN-C-S system has only two conductors in the incoming cable, one phase and the other neutral. The earth is linked to the neutral at the consumer unit. The neutral therefore is really a combined earth/neutral conductor hence the name PME.



In order to avoid the risk of serious electric shock, it is important to provide a path for earth leakage currents to operate the circuit protection, and to endeavour to maintain all metalwork at the same potential. This is achieved by bonding together all metalwork of electrical and non-electrical systems to earth.

The path for leakage currents would then be via the earth itself in TT systems or by a metallic return path in TN-S or TN-C-S systems.

GENERATOR,

AC GENERATOR ALTERNATOR

DIAGRAM   OF AC ALTERNATOR