(1) The Electrical Inspector where the supply voltage exceeds [भाग III—खण्ड 4] भारतकाराजपत्र:असाधारण 117 the notified voltage shall not authorise the supplier to commence supply or recommence the supply, where the supply has been discontinued for a period of six months or more, or the supplier, where the supply voltage is equal to or below the notified voltage but exceeds 650 V, shall not commence supply or recommence the supply where supply has been discontinued for a period of six months or more, to any consumer unless, –
(a) all conductors and apparatus situated on the premises of the consumer are so placed as to be inaccessible except to the designated person;
(b) the consumer has provided and agreed to maintain a separate building or a locked weather proof and fire proof enclosure of agreed design and location, to which the supplier at all times shall have access for the purpose of housing his apparatus and metering equipment, or where the provision for a separate building or enclosure is impracticable, the consumer has segregated the aforesaid apparatus of the supplier from any other part of his own apparatus:
Provided that the segregation shall be made by the fire walls, if the Electrical Inspector considers it to be necessary:
Provided further that in the case of an outdoor installation the consumer shall suitably segregate the aforesaid apparatus belonging to the supplier from his own;
(c) all pole type substations are constructed and maintained in accordance with regulation 52.
(2) Where electricity at voltage exceeding 650 V is supplied, converted, transformed or used, the owner shall, –
(i) maintain safety clearances for electrical apparatus as per relevant standards specification so that sufficient space is available for easy operation and maintenance without any hazard to the operating and maintenance personnel working near the equipment and for ensuring adequate ventilation:
Provided that in case of mines, the safety clearances for electrical apparatus to be as per relevant mining regulations;
(ii) not allow any encroachment below such installation:
Provided that where the Electrical Inspector comes across any such encroachment, he shall direct the owner to remove such encroachments;
(iii) maintain minimum safety working clearances specified in Schedule V for the bare conductors or live parts of any apparatus in outdoor substations excluding overhead lines of installations of voltage exceeding 650 V;
(iv) ensure that the live parts of all apparatus within the reach from any position in which a person may require to be, are suitably protected to prevent danger;
(v) ensure that where the transformer is used, suitable provision shall be made, either by connecting with earth, a point of the circuit at the lower voltage or otherwise, to guard against danger by reason of the said circuit becoming accidentally charged above its normal voltage by leakage from or contact with the circuit at the higher voltage;
(vi) not install a substation or a switching station with apparatus having more than 2000 litre of oil in the basement where proper oil draining arrangement cannot be provided;
(vii) undertake the following measures, where a substation or a switching station with oil-filled apparatus, such as transformer, static condenser, switchgear or oil circuit breaker having more than 2000 litre of oil is installed, whether indoor or outdoors,-
(a) the separation wall or fire barrier walls of thickness and dimensions as specified in the relevant standards shall be provided between the apparatuses and between the apparatus and adjacent building if building wall adjacent to the apparatuses is not rated for four hours fire withstand rating;
(b) provisions shall be made for suitable oil soakpit and where use of more than 9000 litre of oil in any one oil tank, receptacle or chamber is involved, provision shall be made for the draining away or removal of any oil which may leak or escape from the tank, receptacle or chamber containing the same, and special precautions shall be taken to prevent the spread of any fire resulting from the ignition of the oil from any cause and adequate provision shall be made for extinguishing any fire which may occur;
(c) spare oil shall not be stored in the vicinity of any oil filled equipment in any such substation or switching station; and
(d) all the transformers and switchgears shall be maintained in accordance with the maintenance schedules prepared in accordance with the relevant standards;
118 THE GAZETTE OF INDIA : EXTRAORDINARY [PART III—SEC.4]
(viii) without prejudice to the above measures, undertake adequate fire detection and protection arrangement for quenching the fire of the apparatus;
(ix) ensure that every transformer of 10 MVA or reactor of 10 MVAR and above rating shall be provided with automatic fire fighting system as per relevant standards;
(x) undertake the following measures, where it is necessary to locate the substation, or switching station in the basement, namely: –
(a) the transformer room be in the first basement at the periphery;
(b) the direct access to the transformer room be provided from outside and the surrounding walls of four hours fire withstand rating be provided as per relevant standards;
(c) the entrances to the transformer room be provided with fire resistant doors of two hour fire rating and the door shall always be kept closed and a notice of this effect be affixed on outer side of the door;
(d) a curb of a suitable height be provided at the entrance in order to prevent the flow of oil from a ruptured transformer into other parts of the basement;
(e) the cables to primary side and secondary side have sealing at all floors and wall opening of atleast two hours fire withstand rating; and
(f) Fire Retardant Low Smoke Low Halogen cable as per relevant standards be used;
(xi) ensure that oil filled transformers installed indoors in other than residential or commercial buildings are placed on the ground floor or not below the first basement;
(xii) ensure that only dry type transformer shall be used inside the residential and commercial buildings;
(xiii) ensure that cable trenches inside the substations and switching stations containing cables are filled with sand, pebbles or similar non-inflammable materials or completely covered with non-inflammable slabs; and
(xiv) ensure that unless the conditions are such that all the conductors and apparatus may be made dead at the same time for the purpose of cleaning or for other work, the said conductors and apparatus shall be so arranged that these may be made dead in sections, and that work on any such section may be carried on by the person designated or appointed or engaged or permited under these regulations without danger.
(3) The minimum clearances specified in Schedule VI shall be maintained for bare conductors or live parts of any high voltage direct current apparatus in outdoor substations, excluding high voltage direct current overhead lines.
(4) There shall not be tapping of another transmission line from the main line for 66 kV and above class of lines:
Provided that during natural calamities, tapping may be allowed to ensure emergency power supply to affected areas till normalcy is restored.