×
Start where you are. Use what you have. Do what you can.
--Your friends at LectureNotes
Close

Power System-2

by Aayush PatidarAayush Patidar
Type: NoteInstitute: Rajiv Gandhi Proudyogiki Vishwavidyalaya Bhopal Views: 13Uploaded: 4 months ago

Share it with your friends

Suggested Materials

Leave your Comments

Contributors

Aayush Patidar
Aayush Patidar
THE INDIAN ELECTRICITY RULES, 1956 (AS AMENDED UPTO 25TH NOV., 2000) INTRODUCTION The Central Electricity Board had made IE rules in exercise of the powers conferred by section 37 of the Indian Electricity Act, 1910 (9 of 1910) for regulating the generation transmission supply and use of electrical energy and generally to carry out the purposes and Objects of the said act . The salient provisions of the Indian electricity rules are briefly discussed here in :Chapter I – Contains definations Chapter II-Provides required qualifications for appointment of inspectors and officers to assist the inspector under rule 4 and 4A Chapter III- provides the procedure for licence Rule 3 Provides provision for authorization by a supplier or a consumer, or the owner, agent or manager of a mine, or the agent of any company operating in an oil-field or the owner of a drilled well in an oil field or a contractor for the time being under contract with a supplier or a consumer to carry out duties incidental to the generation, transformation, transmission, conversion, distribution or use of energy. Chapter IV - General safety requirements Rule 29 Stipulates that “All electric supply lines and apparatus shall be of Indian Electricity Rules, 1956 sufficient ratings for power, insulation and estimated fault current and of sufficient mechanical strength, for the duty which they may be required to perform under the environmental conditions of installation, and shall be constructed, installed, protected, worked and maintained in such a manner as to ensure safety of human beings, animals and property” Rule 30 Stipulates that “The supplier shall ensure that all electric supply lines, wires, fittings and apparatus belonging to him or under his control, which are on a consumer’ s premises, are in a safe-condition and in all respects fit for supplying energy and the supplier shall take due precautions to avoid danger arising on such premises from such supply lines, wires, fittings and apparatus.” It also provides that: (1) Service-lines placed by the supplier on the premises of a consumer which are underground or which are accessible shall be so insulated and protected by the supplier as to be secured under all ordinary conditions against electrical, mechanical, chemical or other injury to the insulation. (2)The consumer shall, as far as circumstances permit, take precautions for the safe custody of the equipment on his premises belonging to the supplier. (3) The consumer shall also ensure that the installation under his control is maintained in a safe condition. Rule 31 Stipulates requirement to provide Cut-out on consumer’s premises (1)The supplier shall provide a suitable cut-out in each conductor of every service-line other than an earthed or earthed neutral conductor. Where more than one consumer is supplied through a common service-line, each such consumer shall be provided with an independent cut-out at the point of junction to the common service. (2)Every electric supply line other than the earth or earthed neutral conductor of any system or the earthed external conductor of a concentric cable shall be protected by a suitable cut-out by its owner. Rule 32 Stipulates Identification of earthed and earthed neutral conductors and position of switches and cut-outs therein and conditions required to be complied with.
Rule 33 Stipulates that the supplier shall provide and maintain earthed terminal on consumer’s premises near the point of commencement of supply as defined under rule 58. Rule 35 Stipulates that the owner of every medium, high and extra-high voltage installation shall affix permanently in a prominent position a danger notice in Hindi English or local language of the district, with a sign of skull and bones. Rule 36 Stipulates to ensure adequate safety precautions before handling of electric supply lines and apparatus . Rule 41 Stipulates that distinction of different circuits shall be ensured by means of indication of permanent nature. Rule 44 Stipulates requirement of affixing instructions for restoration of persons suffering from electric shock in English or Hindi and the local language of the district. Rule 44 A Provides that “If any accident occurs in connection with the generation, transmission, supply or use of energy in or in connection with, any part of the electric supply lines or other works of any person and the accident results in or is likely to have resulted in loss of human or animal life or in any injury to a human being or an animal, such person or any authorised person of the State Electricity Board/Supplier , not below the rank of a junior Engineer or equivalent shall send to the Inspector a telegraphic report within 24 hours of the knowledge of the occurrence of the fatal accident and a written report in the form set out in Annexure XIII within 48 hours of the knowledge of occurrence of fatal and all other accidents. Where practicable a telephonic message should also be given to the Inspector immediately the accident comes to the knowledge of the authorised officer of the State Electricity Board/Supplier or other person concerned.” Rule 45 Stipulates precautions to be adopted by consumers, Owners, occupiers, electrical contractors, electrical workmen and suppliers for electrical installation work. ChapterV- General conditions relating to supply and use of energy Rule 48 Precaution against leakage before connection Rule 49 Stipulates the requirement of notice in writing to be given to the consumer to inspect and test the consumer’ s installation for Leakage on consumer’s premises . Rule 50 Stipulates the provisions to be observed for the supply and use of energy(a)The following controls of requisite capacity to carry and break the current are to be placed after the point of commencement of supply to the installation, such equipment being in addition to any equipment installed for controlling individual circuits or apparatus:(i) a linked switch with fuse(s) or a circuit breaker by low and medium voltage consumers. (ii) a linked switch with fuse(s) or a circuit breaker by HV consumers having aggregate installed transformer/apparatus capacity up to 1000 KVA to be supplied at voltage upto 11KV and 2500 KVA at higher voltages (above 11 KV and not exceeding 33KV). (iii) a circuit breaker by HV consumers having an aggregate installed transformer/apparatus capacity above 1000 KVA and supplied at 11 KV and above 2500 KVA supplied at higher voltages (above 11 KV and not exceeding 33KV)
Rule 51 Stipulates the Provisions applicable where energy at converted, transformed or used: medium, high or extra-high voltage is supplied, Rule 54 Stipulates that a supplier shall not permit the voltage at the point of commencement of supply to vary from the declared voltage: (i) in the case of low or medium voltage, by more than 6 per cent, or; (ii) in the case of high voltage, by more than 6 per cent on the higher side or by more than 9 percent on the lower side, or; (iii) in the case of extra-high voltage, by more than 10 per cent on the higher side or by more than 12.5 per cent on the lower side. Rule 55 Stipulates that Declared frequency of Ac supply to consumer to varry from the declared frequency by more than 3%. Rule 56 Stipulates that the supplier may affix one or more seals to meters and cut outs and no person other than the supplier shall break any such seal. Rule 57 Stipulates the provision to ensure correctness of Meters, maximum demand indicators and other apparatus on consumer’s premises Rule 58 States the Point of commencement of supply- “The point of commencement of supply of energy to a consumer shall be deemed to be the point at the incoming terminal of the cut-outs installed by the consumer under rule 50.” Rule 59 Provides Precautions to be taken against failure of supply and notice of failures to be given . Rule 76 Stipulates Maximum stresses “ Factors of safety” (i) for metal supports - 1.5 (ii)for mechanically processed concrete supports - 2.0 (iii)for hand-moulded concrete supports - 2.5 (iv)for wood supports - 3.0 (b) The minimum factor of safety for stay-wires, guard-wires or bearer-wires shall be 2.5 (c) The minimum factor of safety for conductors shall be 2. Rule 77 Stipulates Clearance above ground of the lowest conductor of an overhead line, including service lines, (1) Erected across a street shall at any part thereof be at a height of less than(a) for low and medium voltage lines 5.8 metres (b) for high voltage lines 6.1 metres (2) Erected along any street shall at any part thereof be at a height less than(a) for low and medium voltage lines 5.5 metres (b) for high voltage lines 5.8 metres (3) Erected elsewhere than along or across any street shall be at a height less than (a) for low, medium and high voltages lines upto and including 11,000 volts,if bare 4.6 metres (b) for low, medium and high voltage lines upto and including 11,000 volts, if insulated 4.0 metres (c) for high voltage lines above 11,000 volts 5.2 metres (4) For extra-high voltage lines the clearance above ground shall not be less than 5.2 metres plus 0.3 metre for every 33,000 volts or part thereof by which the voltage of the line exceeds 33,000 volts; Provided that the minimum clearance along or across any street shall not be less than 6.1 metres. Rule 79 Clearance from buildings of low and medium voltage lines and service lines-
(1)Where a low or medium voltage, overhead line passes above or adjacent to or terminates on any building, the following minimum clearances from any accessible point, on the basis of maximum sag, shall be observed:(a) for any flat roof, open balcony, varandah roof and lean-to-roof(i) when the line passes above the building a vertical clearance of 2.5 metres from the highest point (ii)when the line passes adjacent to the building a horizontal clearance of 1.2 metres from the nearest point, and (b)for pitched roof(i )when the line passes above the building a vertical clearance of 2.5 metres immediately under the lines, and (ii) When the line passes adjacent to the building a horizontal clearance of 1.2 metres. Rule 80 Clearances from buildings of high and extra-high voltage lines Where a high or extra-high voltage overhead line passes above or adjacent to any building or part of a building it shall have on the basis of maximum sag (1) Vertical clearance above the highest part of the building immediately under such line, of not less than(a) for high voltage lines upto and including 33,000 volts 3.7 metres (b) for extra-high voltage lines 3.7 metres plus 0.30 metre for every additional 33,000 volts or part thereof. (2) Horizontal clearance between the nearest conductor and any part of such buildingshall, on the basis of maximum deflection due to wind pressure, be not less than(a) for high voltage lines upto and including 11,000 volts 1.2 metres (b) for high voltage lines above 11,000 volts and up to and including 33,000 volts 2.0 metres For extra-high voltage lines 2.o metres plus 0.3 metre for every additional33,000 volts for part thereof. Rule 81 Conductors at different voltages on same supports- Where conductors forming parts of systems at different voltages are erected on the same supports, the owner shall make adequate provision to guard against danger to linesman and others from the lower voltage system being charged above its normal working voltage by leakage from or contact with the higher voltage system and the methods of construction and the clearances between the conductors of the two systems shall be subject to prior approval of the Inspector. Rule 85 Stipulates Maximum interval between supports.-All conductors shall be attached to supports at intervals not exceeding the safe limits based on the ultimate tensile strength of the conductor and the factor of safety prescribed in rule 76. Rule 87 Lines crossing or approaching each other:Minimum clearances in metres between lines crossing each other Sl No. 1 2 3 4 5 Nominal system voltage . Low &Medium 11-66KV 110-132KV 220KV 400 KV 11-66 KV 110-132KV 220KV 400KV 2.44 2.44 3.05 4.58 5.49 3.05 3.05 3.05 4.58 5.49 4.58 4.58 4.58 4.58 5.49 5.49 5.49 5.49 5.49 5.49

Lecture Notes