(1) Earthing of support of overhead lines up to 33 kV shall be provided as under, namely: –
(a) all metal supports and all reinforced and pre-stressed cement concrete supports of overhead lines and metallic fittings attached thereto, shall be permanently and effectively earthed by providing a continuous [भाग III—खण्ड 4] भारतकाराजपत्र:असाधारण 131 earth wire and securely fastened to each pole and connected with the earth at each support and the metallic fittings attached thereto shall also be permanently and effectively earthed;
(b) metal cross arms and insulator pins for Plain Cement Concrete and Pre-Stressed Cement Concrete poles shall be bonded together and normally earthed at every pole;
(c) for locations involving railways, electric line crossings and special structures, pipe or rod type earthing shall be provided;
(d) all steel poles on which switches, transformers, fuses are mounted shall be earthed;
(e) for poles of the electric lines below 650 V guarding arrangement with continuous earth wire or messenger wire in case of aerial bunched cable shall be provided and shall be connected to earth at three equidistant points in every km; and
(f) each stay-wire shall be similarly earthed unless insulator of same voltage class as that of line has been placed in it at a height not less than three metre from the ground and shall be provided with insulated tube up to three metre height from the ground.
(2) For 66 kV and above voltage class overhead line, earthing and requirement of earth wire shall be as per the regulations notified by the Authority under clause (e) of sub-section (2) of section 177 of the Act.