Bses project report

COMPANY PROFILE History of Electricity in Delhi: The history of electricity in Delhi dates back to 1905 when M/s John Flemming Company was awarded the license as per Indian Electricity Act, 1903, for generation and distribution of power in Delhi. Electricity those days was a luxury and the privilege of the high ranking British officials and a few rich people. It was a rare and costly commodity with a perception of being dangerous. Infact even rich Indian accepted this at a much later stage. M/s John Fleming Company was replaced by the Delhi Tramway and Lighting Company, which was subsequently renamed as Delhi Electricity Supply & Traction Company. In 1939, The Delhi Central Electric Power Authority (DCEPA) was formed to run the services. In 1951, the DCEPA was taken over by the Delhi State Electricity Board, constituted under Indian Electricity (Supply) Act 1948. In 1958, Delhi Electricity Supply Undertaking came into existence and was once again converted to Delhi Vidyut Board in 1997. In July 2002, Delhi Vidyut Board unbundled into five successor entities – the three distribution companies, a transmission and a holding company. Two of the three distribution companies have been handed over to BSES, and one to TATA POWER.

About BSES: BSES Limited is India's premier utility engaged in the generation, transmission and distribution of electricity. Formerly, known as Bombay Suburban Electric Supply Limited, it was incorporated on 1st October 1929, for the distribution of electricity in the suburbs of Mumbai, with a pioneering mission to make available uninterrupted, reliable, and quality power to customers and provide value added services for the development of the power and infrastructure sectors. BSES caters to the needs of 2.07 million consumers over an area of 384 sq. km. with a maximum system demand of approximately 1198 MVA. With 7 decades in the field of power distribution, the

Electricity Supply Division of BSES has achieved the distinction of operating its distribution network with 99.98% on-line reliability and has a distribution loss of only 29.9%. BSES was amongst the first utilities in India to adopt computerization in 1967 to meet the increasing workload and to improve services to its customers. With a view to optimally utilize trained manpower and expertise in the field of power, the company commenced contracting activities in 1966 by undertaking turnkey electrical contracts, thermal, hydro and gas turbine installations and commissioning contracts, transmission line projects etc. BSES set up its own 500 MW Thermal Power Plant and the first 2 x 250 MW units of Dahanu Power Station were synchronized and began commercial operation during 1995- 1996. A dedicated 220 kV double circuit transmission line network with three 220 / 33 kV receiving stations have been installed to evacuate the power to the distribution area of the Company. This demonstrates BSES’ in-house capabilities ranging from engineering, operation & maintenance of power plants and transmission and distribution systems. BSES through international competitive bidding acquired an equity stake of 51% in three of the four Distribution Companies of Orissa. At present, BSES along with its subsidiaries provide electricity to more than 2.7 million consumers in an area covering about 1,23,000 sq. km with an estimated population of 34 million. In July 2002, Delhi Vidyut Board unbundled into five successor entities – the three distribution companies, a transmission and a holding company. Two of the three distribution companies have been handed over to BSES, and one to TATA POWER. As a part of its active support to the privatization process, BSES has recently acquired an equity stake of 51% in two of the three Distribution Companies of Delhi after unbundling and privatization of the erstwhile Delhi Vidyut Board. The two distribution companies, BSES Rajdhani Power Limited covering South and West areas and BSES Yamuna Power Limited covering Central and East regions provide electricity to around 22 lakhs consumers spread across an area of 960 sq kms (approx). BSES became part of the Reliance Group on January 18, 2003. BSES will be renamed ‘Reliance Energy’ to reflect the change in ownership, and to leverage brand equity of Reliance.

The new name ‘Reliance Energy’ will directly communicate association with the internationally respected Reliance Group, and reflect the larger dimension of BSES’ future plans. So presently BSES deals with mainly distribution sector in the country BSES Delhi Following the privatization of Delhi‟s power sector and unbundling of the Delhi Vidyut Board in July 2002, the business of power distribution was transferred to BSES Yamuna Power Limited (BYPL) and BSES Rajdhani Power Limited (BRPL). These two of the three successor entities distribute electricity to 22.6 lakh customers in two thirds of Delhi. The Company acquired assets, liabilities, proceedings and personnel of the Delhi Vidyut Board as per the terms and conditions contained in the Transfer Scheme. 1.5.4 BSES Rajdhani Power Limited (BRPL) BRPL distributes power to an area spread over 750 sq. km with a population density of 1360 per sq km. Its‟ over 12.2 lakh customers are spread 19 districts across South and West areas including Alaknanda, Khanpur, Vasant Kunj, Saket, Nehru Place, Nizamuddin, Sarita Vihar, Hauz Khas, R K Puram, Janakpuri, Najafgargh, Nangloi, Mundka, Punjabi Bagh, Tagore Garden,Vikas Puri,Palam and Dwarka. Since taking over distribution, BSES‟ singular mission has been to provide reliable and quality electricity supply. BSES has invested over Rs 3500 crore on upgrading and augmenting the infrastructure which has resulted in a record reduction of AT&C losses. From a high of 63. % AT&C losses in BYPL area the losses have come down to 29.8% a record reduction around 33%.Similarly, in BRPL area AT&C losses have been reduced from 52.% to 27.% - a record reduction of 29%. BSES Yamuna Power Limited (BYPL) BYPL distributes power to an area spread over 200 sq kms with a population density of 4230 per sq km. Its 10.4lakh customers are spread over 14 districts across Central and East areas including Chandni Chowk, Daryaganj, Paharganj, Shankar Road, Patel Nagar, G T Road, Karkardooma, Krishna Nagar, Laxmi Nagar, Mayur Vihar, Yamuna Vihar, Nand Nagri and Karawal Nagar. BYPL distributes

power to an area spread over 200 sq kms with a population density of 4230 per sq km. Its 10.4lakh customers are spread over 14 districts across Central and East areas including Chandni Chowk, Daryaganj, Paharganj, Shankar Road, Patel Nagar, G T Road, Karkardooma, Krishna Nagar, Laxmi Nagar, Mayur Vihar, Yamuna Vihar, Nand Nagri and Karawal Nagar.

Geographical Reach Delhi Distribution Area

Business of the Organization

Delhi Supply Division: Caters to an area of 950 sq. Kms. Supply Area covers South Delhi, East Delhi, West Delhi and Central Delhi. Consumers include houses, residential complexes, high rise buildings, commercial Complex medium and large industrial houses, government establishment like Airport, Worship places, Milk Dairy, Mother Dairy and Municipal Hospitals, Sewerage projects etc. 1. Caters to more than 22 lakh consumers.

2. Provides highly reliable and continuous supply. 3. All consumers are given metered supply only. 4. Reliability 99.99 %

Supply area

960 sq. kms(approx)

No. of Consumers Population covered System peak Power Transformer No. of Dist. Substations Dist Transformer capacity

Above 22 lakhs Above 80 lakh 5320 MW(approx) 6024 MVA 9338(approx 5178.411 MVA

Power Factor 66 kV Capacitors

0.99 459.91 MVAr

33 kV Capacitors 11 kV Capacitors

226.52 MVAr 852.97 MVAr

LT Capacitors

297.20 MVAr

DELHI DISTRIBUTION NETWORK • 66/33/11 kV Sub Transmission Network. • Receiving Stations.

SALIENT FEATURES 1. Unit type system at 66/33/11 kV radial system 2. Open Ring type system at 11 kV Mesh Network. 3. Partial Ring type system at L T Secondary Distribution level. 4. Distribution system with overhead cum underground cable

network

Chapter: 2

Substations

Pole Mounted Sub-station is a large, free standing, outdoor electrical equipment that is mostly located in residential places. Its main purpose is to step-down the lethal 11kV to 415/240V for light, commercial and residential loads (consumers)... The 11kV line is connected to the Step-Down Transformer (11kV/415V) though a gang isolator and fuses. The lighting arrestors are installed on the H.T side to protect the Sub-Station from lightening strokes. The transformer steps down the 11kV to 415V, 3phase, 4-wire supply. The voltage between any two lines is 415V, and between any line and a phase is 240V. The Oil Circuit Breaker (O.C.B), installed on the L.T side automatically isolates the transformer from the consumers in case of any fault. The Pole Mounted Sub-stations are generally used for transformer capacity up to 200kVA They should be periodically checked for dielectric strength of oil in the transformer and (OCB) In case of repair the transformer or (O.C.B) both the Gang Isolators and (O.C.B) should be shut off.

Indoor substation layout

Outdoor substation basic layout

Outdoor substation without enclosure This kind of outdoor substations based on weatherproof equipment is commonly used in countries such as UK and India for example. These substations are generally included in MV rings and include:



Two functional units dedicated to the connection of the substation to the ring One functional unit for the supply and the protection of the MV/LV power transformer generally done by a circuit breaker unit



One single MV/LV Power transformer



One LV distribution panel.



The transformer and the LV panel can be installed in dedicated outdoor type housing. Advantage and disadvantage of outdoor substation as compared to indoor substation The outdoor substation has following advantages: • The construction work needed is much

smaller than the indoor substation. • Installation cost of switchgear is low. • Adequate space between two adjoining equipment can be provided. • Erection is made in less time. • Whole structure is properly viewed, so that fault can be easily located. • The scheme extension is easier. Disadvantages of outdoor substations are, • Dust and dirt use to formulate on contact switches. This makes maintenance cost higher. • In rainy or snow falling seasons switching becomes complicated. • The installation suffers from security as unauthorized persons can easily penetrate the structure. Comparision between outdoor and indoor substation

Outdoor

Indoor

More space required

Less space required

Less time required for erection

More time required for erection

Easy future extension

Difficult future extension

Easier fault location because of equipment being in full view.

Difficult fault location because of equipment not being in full view.

Low capital cost

High capital cost

Difficult operation

Easier operation

Possibility of fault escalation is less.

Plausibility of fault escalation is more.

Step Up Substation Step up substations are associated with generating stations. Generation of power is limited to low voltage levels due to limitations of the rotating alternators. These generating voltages must be stepped up for economical transmission of power over long distance. So there must be a step up substation associated with generating station.

Step Down Substation The stepped up voltages must be stepped down at load centers, to different voltage levels for different purposes. Depending upon these purposes the step down substation are further categorized in different sub categories.

Primary Step Down Substation The primary step down sub stations are created nearer to load center along the primary transmission lines. Here primary transmission voltages are stepped down to different suitable voltages for secondary transmission purpose.

Secondary Step Down Substation Along the secondary transmission lines, at load center, the secondary transmission voltages are further stepped down for primary distribution purpose. The stepping down of secondary transmission voltages to primary distribution levels are done at secondary step down substation.

Distribution Substation Distribution substation are situated where the primary distribution voltages are stepped down to supply voltages for feeding the actual consumers through a distribution network.

Bulk Supply or Industrial Substation

Bulk supply or industrial substation are generally a distribution sub – station but they are dedicated for one consumer only. An industrial consumer of large or medium supply group may be designated as bulk supply consumer. Individual step down substation is dedicated to these consumers. Mobile Substation The mobile substations are also very special purpose sub – station temporarily required for construction purpose. For big construction purpose this substation fulfills the temporary power requirement during construction work.

Hybrid Gas Isolated substation– GIS (HGIS) Hybrid – GIS (HGIS) is a new type of high-voltage switchgear which is compact in size, reliable in operation and economical in cost. HGIS is mainly composed of Bushings (BSG), Disconnecting Switch (DS), Earthing Switch (ES), Circuit Breaker (CB), and Current Transformer

(CT), etc. Since a three-position disconnecting and earthing switch (DES) is used, HGIS features not only compactness, but also safety. Apart from compactness, HGIS requires very short time for onsiteerection. The main advantages of HGIS are reliable operation, performance, high degree of intelligence and very little requirement for maintenance. HGIS is a combination of advantages of Air Insulated Switchgear (AIS) and Gas Insulated Switchgear (GIS) equipment. Compared with AIS, HGIS greatly saves space and gets rid of the complications of installing and maintaining many equipment in the substation. Compared with the GIS, HGIS features faster and simpler erection, easier for service and replacement. 40.5 ~ 252kV HGIS is an outdoor three-phase AC transmission equipment using SF6 gas as the insulating medium. It can be used for a variety of applications viz. transmission and distribution substations, power plants, factories, railways, etc.

Main Product Features Light weight The three phases are located in separated enclosures. There is very little interference between the phases. Enclosure is an aluminum structure, light in weight, having good conductivity and no eddy current loss. 



Excellent Breaking Performance : Circuit breaker adopts the two gas chamberself-arc-extinguishing principle. It uses its own energy of the arc to improve the arc extinguishing capability. Therefore the energy used for the operating mechanism is very much reduced, and the reliability of the product is greatly improved as a result. High reliability of the operating mechanism : Circuit Breaker uses a state of art spring mechanism which requires very low operating energy and hence less maintenance. The three

phases are mechanically interlinked which ensures high level of synchronized reliability of the product. Electrical operating mechanism is used for the DS and ES of the three-position switch (DES). The DS and ES are mechanically interlocked so as to avoid fault operation, which ensures high safety and reliability. 

Easy Erection and Installation at Site : HGIS is transported as a whole unit to the site. Erection on the site is very easy and requires very little time. Only some simple connections and gas filling is needed before testing and commissioning which makes it easy to handle.



Economic Advantage : HGIS integrates Circuit Breaker (CB), Disconnecting Switch (DS), Earthing Switch (ES), Current Transformer (CT), Fast Earthing Switch (FES), Voltage Transformer (VT)), Surge/ Lightening Arrestor (SA/ LA) and other components into one module that saves significantly land and space requirement, which is a very scarce resources in large cities.

Equipments and essential parts of substations :     

Transformers RMU ( sf6 Circuit breaker ) Ring Main Unit Vaccum Circuit Breaker Air Circuit Breaker Meters

Detailed description and discussion about all these are done below .  Transformers All the three phase transformers are delta – star connected as at the consumer end single phase supply is provided so neutral can be there for a return path n main path can be any of the R-Y-B .

There are 3 main parts in the distribution transformer: 

Coils/winding –where incoming alternate current (through primary winding) generates magnetic flux, which in turn develop a magnetic field feeding back a secondary winding



Magnetic core –allowing transfer of magnetic field generated by primary winding to secondary winding by principle of magnetic induction First 2 parts are known as active parts



Tank– serving as a mechanical package to protect active parts, as a holding vessel for transformer oil used for cooling and insulation and bushing (plus auxiliary equipment where applicable)



Bushing - All materials carrying an electric charge generate an electric field. When an energized conductor is near any material at earth potential, it can cause very high field strengths to be formed, especially where the field lines are forced to curve sharply around the earthed material. The bushing controls the shape and strength of the field and reduces the electrical stresses in the insulating material.

 RMU / SF6 circuit breaker assembly A circuit breaker in which the current carrying contacts operate in sulphur hexafluoride or SF6 gas is known as an SF6 circuit breaker. SF6 has excellent insulating property and it has a high electronegativity. Therefore, it has high affinity of absorbing free electrons. Whenever a free electron collides with the SF6 gas molecule, it is absorbed by that gas molecule and forms a negative ion with the following processes.

These negative ions are much heavier than a free electron and therefore the over all mobility of the negatively charged particle in the medium is considerably reduced compared to other gases. As the mobility of charged particle is reduced, therefore the severity of arcing shall also be affected and reduced. There are 3 types of sf6 circuit breaker : 1. Single interrupter SF6 CB applied for up to 245 KV(220 KV) system. 2. Single pressure puffer type SF6 CB applied for up to 420 KV(400 KV) system. 3. Double pressure puffer type SF6 CB applied for up to 800 KV(715 KV) system.

Disadvantages of SF6 CB The SF6 gas is identified as a greenhouse gas, safety regulation are being introduced in many countries in order to prevent its release into atmosphere. Puffer type design of SF6 CB needs a high mechanical energy which is almost five times greater than that of oil circuit breaker.

Vacuum Circuit Breaker The modern vacuum bottle, which is used in both breakers and contactors, is normally made from ceramic material. It has pure oxygen-free copper main connections; stainless steel bellows and has composite weld-resistant main contact materials. A typical contact material comprises a tungsten matrix impregnated with a copper and antimony alloy to provide a low melting point material to ensure continuation of the arc until nearly current zero. Because it is virtually impossible for electricity to flow in a vacuum, the early designs displayed the ability of current chopping i.e. switching off the current at a point on the cycle other than current zero. This sudden instantaneous collapse of the current generated extremely high-voltage spikes and surges into the system, causing failure of equipment. Another phenomenon was pre-strike at switch on. Due to their superior rate of dielectric recovery, a characteristic of all vacuum switches was the production of a train of pulses during the closing operation. Although of modest magnitude, the high rate of rise of

voltage in prestrike transients can, under certain conditions produce high-insulation stresses in motor line end coils. Subsequent developments attempted to alleviate these shortcomings by the use of ‘softer’ contact materials, in order to maintain metal vapor in the arc plasma so that it did not go out during switching. Unfortunately, this led to many instances of contacts welding on closing. Restrike transients produced under conditions of stalled motor switch off was also a problem. When switching off a stalled induction motor, or one rotating at only a fraction of synchronous speed, there is little or no machine back emf, and a high voltage appears across the gap of the contactor immediately after extinction. If at this point of time the gap is very small, there is the change that the gap will break down and initiate a restrike transient, puncturing the motor’s insulation. Modern designs have all but overcome these problems. In vacuum contactors, higher operating speeds coupled with switch contact material are chosen to ensure high gap breakdown strength, produce shorter trains of pulses

 Air Circuit Breaker This type of circuit breakers, is those kind of circuit breaker which operates in air at atmospheric pressure. After development of oil circuit breaker, the medium voltage air circuit breaker (ACB) is replaced completely by oil circuit breaker in different countries. But in countries like France and Italy, ACBs are still preferable choice up to voltage 15 KV. It is also good choice to avoid the risk of oil fire, in case of oil circuit breaker. In America ACBs were exclusively used for the system up to 15 KV until the development of new vacuum and SF6 circuit breakers.

Working principle of air circuit breaker(ACB)

The working principle of this breaker is rather different from those in any other types of circuit breakers. The main aim of all kind of circuit breaker is to prevent the reestablishment of arcing after current zero by creating a situation where in the contact gap will withstand the system recovery voltage. The air circuit breaker does the same but in different manner. For interrupting arc it creates an arc voltage in excess of the supply voltage. Arc voltage is defined as the minimum voltage required maintaining the arc. This circuit breaker increases the arc voltage by mainly three different ways, 1. It may increase the arc voltage by cooling the arc plasma. As the temperature of arc plasma is decreased, the mobility of the particle in arc plasma is reduced, hence more voltage gradient is required to maintain the arc. 2. It may increase the arc voltage by lengthening the arc path. As the length of arc path is increased, the resistance of the path is increased, and hence to maintain the same arc current more voltage is required to be applied across the arc path. That means arc voltage is increased. 3. Splitting up the arc into a number of series arcs also increases the arc voltage. The first objective is usually achieved by forcing the arc into contact with as large an area as possible of insulating material. Every air circuit breaker is fitted with a chamber surrounding the contact. This chamber is called „arc chute‟. The arc is driven into it. If inside of the arc chute is suitably shaped, and if the arc can conform to the shape, the arc chute wall will help to achieve cooling. This type of arc chute should be made from some kind of refractory material. High temperature plastics reinforced with glass fiber and ceramics are preferable materials for making arc chute. The second objective that is lengthening the arc path is achieved concurrently with the first objective. If the inner walls of the arc chute is shaped in such a way that the arc is not only forced into close proximity with it but also driven into a serpentine channel projected on the arc chute wall. The lengthening of the arc path increases the arc resistance. The third objective is achieved by using metal arc slitter inside the arc chute. The main arc chute is divided into numbers of small compartments by using metallic separation plates. These metallic separation plates are actually the arc splitters and each of the small compartments behaves as individual mini arc chute. In this system the initial arc is split into a number of series arcs, each of which will

have its own mini arc chute. So, each of the arc splits has its own cooling and lengthening effect. This collectively, increases the overall arc voltage and helps in quenching.



RELAY

 Overcurrent Relays • Protection against excess current was naturally the earliest protection systems to evolve • From this basic principle has been evolved the graded over current system, a discriminate fault protection. • “over current” protection is different from “over load protection”. • Overload protection makes use of relays that operate in a time related in some degree to the thermal capability of the plant to be protected. • Over current protection, on the other hand, is directed entirely to the clearance of the faults, although with the settings usually adopted some measure of overload protection is obtained.

Types of over current relays • Based on the relay operating characteristics , overcurrent relays can be classified into three groups – Definite current or instantaneous – Definite time – Inverse time

DEFINITE-CURRENT RELAYS • This type of relay operates instantaneously when the current reaches a predetermined value.

DEFINITE TIME CURRENT RELAYS • This type of relay operates after a definite time when the current reaches a predetermined value.

INVERSE TIME RELAYS • The fundamental property of these relays is that they operate in a time that is inversely proportional to the fault current. Inverse time relays are generally classified in accordance with their characteristic curve that indicates the speed of operation. • Inverse-time relays are also referred as inverse definite minimum time or IDMT over current relays

SETTING

THE

PARAMETERS

OVERCURRENT RELAY Pick-up setting

OF

TIME

DELAY

The pick-up setting, or plug setting, is used to define the pick-up current of the relay, and fault currents seen by the relay are expressed as multiples of plug setting. • Plug setting multiplier (PSM) is defined as the ratio of the fault current in secondary Amps to the relay plug setting. • For phase relays the pick-up setting is determined by allowing a margin for overload above the nominal current, as in the following expression Pick-up setting = (OLF x Inom) / CTR Where, OLF = Overload factor that depends on the element being protected. Inom = Nominal circuit current rating, and

CTR = CT Ratio

Time dial setting • The time-dial setting adjusts the time –delay before the relay operates whenever the fault current reaches a value equal to, or greater than the relay setting. • The time-dial setting is also referred to as time multiplier setting (TMS)

DISCRIMINATION BY TIME In this method an appropriate time interval is given by each of the relays controlling the CBs in a power system to ensure that the breaker nearest to the fault location opens first.

Thermal Relays

The coefficient of expansion is one of the basis properties of any material. Two different metals always have different degree of linear expansion. A bimetallic strip always bends when it heated up, due to this inequality of linear expansion of two different metals.

Working Principle of Thermal Relay A thermal relay works depending upon the above mentioned property of metals. The basic working principle of thermal relay is that, when a bimetallic strip is heated up by a heating coil carrying over current of the system, it bends and makes normally open contacts.

Construction of Thermal Relay The construction of thermal relay is quite simple. As shown in the figure above the bimetallic strip has two metals – metal A and metal B. Metal A has lower coefficient of expansion and metal – B has higher coefficient of expansion. One heating coil is would on the bimetallic strip. When over current flows through the heating coil, it heats up the bimetallic strip. Due to the heat generated by the coil, both of the metals are expanded. But expansion of metal B is more than expansion of metal A. Due to this dissimilar expansion the bimetallic strip will bend towards metal A. The strip bends, the No contact is closed which ultimately energizes the trip coil of a circuit breaker. The heating effect is not instantaneous. As per Joule’s law of heating, the amount of heat generated,

where I is the

over current flowing through the heating coil of thermal relay. R is the electrical resistance of the heating coil. t is the time for which the current I flows through the heating coil. Hence from the above equation it is clear that, heat generator by the coil is directly proportional to the time during which the over current flows through the coil. Hence there is a prolonged time delay in the operation of thermal relay. That is why this type of relay is generally used where over load is allowed to flow for a predetermined amount of time before it trips. If overload or over current falls down to normal value before this predetermined time, the relay will not be operated to trip the protected equipment. A typical application of thermal relay is overload protection of electric motor.

Increasing efficiency and reduction of losses Introduction : In the previous financial year, BSES has reported a loss of nearly 42%, of which 6-8% are the transmission losses, rest 34-36% is the loss reported due to theft in various areas in Delhi. BSES has introduced a new DT cleaning programme to reduce the theft and installation and upgradation of new meters/HVDS or LVDS system in various areas. METHODS TO REDUCE THEFT : 1. In Delhi, BSES has introduced a new armoured cable (yellow in color) to reduce the transmission loss due to theft in various parts of the city. 2. Also, the use of new electricity meters is incorporated, the new meters are installed outside the residences and are resistant to heat, and water. 3. Regular surprise raids are carried out in various parts of the city to reduce and fine the offenders.

New Genus Meters

Electricity act, 2003 An Act to consolidate the laws relating to generation, transmission, distribution, trading and use of electricity and generally for taking measures conducive to development of electricity industry, promoting competition therein, protecting interest of consumers and supply of electricity to all areas, rationalization of electricity tariff, ensuring transparent policies regarding subsidies, promotion of efficient and environmentally benign policies, constitution of Central Electricity Authority, Regulatory Commissions and establishment of Appellate Tribunal and for matters connected therewith or incidental thereto.

INVESTIGATION AND ENFORCEMENT Section 126: (Assessment): --(1) If on an inspection of any place or premises or after inspection of the equipments, gadgets, machines, devices found connected or

used, or after inspection of records maintained by any person, the assessing officer comes to the conclusion that such person is indulging in unauthorized use of electricity, he shall provisionally access to the best of his judgement the electricity charges payable by such person or by any other person benefited by such use.

(2) The order of provisional assessment shall be served upon the person in occupation or possession or in charge of the place or premises in such manner as may be prescribed.

1[(3) The person, on whom an order has been served under subsection (2) shall be entitled to file objections, if any, against the provisional assessment before the assessing officer, who shall, after affording a reasonable opportunity of hearing to such person, pass a final order of assessment within thirty days from the date of service of such order of provisional assessment of the electricity charges payable by such person.]

(4) Any person served with the order of provisional assessment, may, accept such assessment and deposit the assessed amount with the licensee within seven days of service of such provisional assessment order upon him. Inspection receipts from the enforcement teams:

REFERENCES AND BIBLIOGRAPHY Following Websites has been used for reference :1 . www.bsesdelhi.com 2. www.electrical4u.com 3. Wikipedia