Insulators. In general, the type and material of the insulators shall be selected based on the characteristics of the zones crossed by the lines, taking into consideration the good practices and experiences of the transmission lines built in Peru and in similar zones. In this regard, the CONCESSIONAIRE shall investigate what contaminating agents or potential sources of contamination are present in the zones crossed by the line, which may affect the insulators’ operation. The insulation coordination studies that involve insulators shall comply with standards IEC 60815-1 and IEC 60815-2, in particular with regard to contamination. From the results of this research, the CONCESSIONAIRE shall determine the measures to minimize the impact of contamination, such as line section layout, increase of creepage distance, use of rings to improve the performance of insulators contaminated in wet areas, etc. The results of the study shall also allow for the selection of the material and insulator type to be used. Insulators shall ensure the insulation level required against atmospheric surges, switching surges and industrial frequency surges, for the same altitude conditions previously discussed and the insulation levels defined in Point 2.2.3 of this annex. In all cases, the proper mechanical strength of the insulators shall be verified, in accordance with the work conditions they are subjected to; evaluating, if necessary, the use of double chains or insulators with a greater breaking load.
Insulators. In general, the type and material of the insulators shall be selected based on the characteristics of the zones that cross the lines, taking into consideration the good practices and experiences of the transmission lines built in Peru and in similar zones. In this regard, the Concession Holder shall investigate what contaminating agents or potential sources of contamination are present in the zone, which may affect the insulators’ operation. The insulation coordination studies shall comply with standards IEC 60815-1 and IEC 60815-2, in particular with regard to contamination From the results of this research, the measures to minimize the impact of contamination, such as the use of glass insulators with silicone liner, line section layout, increase of creepage distance, use of equipotential rings to improve the performance of insulators contaminated in wet areas, etc., shall be determined. The insulators of 220 kV lines shall be selected from the tempered glass or porcelain types, with a homogeneous structure and standard and/or anti-mist (fog) type, with forged steel or galvanized malleable iron metal parts, provided with lock pins manufactured with corrosion- resistant material. The insulator chains shall be comprised of the number of units required to ensure a suitable creepage length according to a) the contamination level of the areas crossed by the lines, b) their altitude above sea level and c) the maximum voltage level of the system. Similarly, these chains shall ensure the insulation level required against atmospheric surges, switching surges and industrial frequency surges, for the same altitude conditions previously discussed and the insulation level defined in section 2.2.4 of this annex. The number of insulators to be considered per suspension chain -based on the altitude and voltage level of the facilities- is the one indicated as a reference below, which shall be assessed in the Pre-Operability Study:
Insulators. Each insulator shall be of such pattern, design and material that, when mounted on its pin, it will withstand, without injury, and without being pulled off the pin, the ultimate strength of the conductor which it supports.
Insulators. Bus support insulators shall be interchangeable, high creep, high strength, wet process, fine glazed porcelain. Alternatively good quality cast resin insulators.
Insulators. In general, the type and material of the insulators will be selected according to the characteristics of the areas crossed by the lines, taking into account the good practices and experiences of previous transmission lines built in Peru in similar areas. In that sense, the Concessionaire must research those contaminants or potential sources of contamination existing in the area that could affect the performance of the insulators. Based on the results of the research, it is necessary to determine the measures minimizing the impact of the contamination, such as: use of silicone insulated glass insulators, layout of the line routing, increase of the leakage line, use of equipotential rings improving the performance of contaminated insulators in wet areas, etc. 500 kV and 220 kV line insulators shall be evaluated between between homogeneous, standard, anti-fog tempered or porcelain glass, with forged steel or malleable galvanized iron, provided with locking pins made of corrosion-resistant material. Insulator chains will be made up of the necessary number of units to ensure adequate leakage length according to the level of contamination of areas through which the lines cross, their altitude above sea level and the maximum voltage level of the system. Similarly, these chains must guarantee the required insulation level against surges of atmospheric surges, switching undervoltages and overvoltages at industrial frequency, for the same previously mentioned altitude conditions and the levels of insulation defined in section 2.2.5 of this Annex. The number of insulators to be considered by suspension chain, according to altitude and facility voltage level, which will be evaluated in the Pre-Operative Study, is the following: Altitude Units per suspension chain In the case of larger angle, terminal and anchor structures, the chains will use an additional (01) insulator to those used in the suspension chains. The Concessionaire will establish the technical characteristics of insulators to be used in the lines, in such a way as to ensure adequate insulation levels; however, as a reference, the following are required insulator characteristics: Characteristics Value Type of insulator Fog Insulating material Tempered glass Manufacturing standard IEC -60305 Disc diameter 330 mm Spacing per insulator 146 mm Leakage line length 440 mm Breaking load 160 kN In all cases adequate mechanical insulator strength must be verified, according to the working conditions to which they ...
Insulators. 6.1 Bus support insulators shall be interchangeable, high creep, high strength, wet process, fine glazed porcelain. Alternatively good quality cast resin insulators.
6.1 Insulator shall be mounted in such a way so as to permit easy removal or replacement without disassembly of the bus. The insulator mounting plate shall be designed for cantilever loading to withstand the short circuit.
6.2 The conductor shall be fastened on the insulator through fixed and slip joints so as to allow conductor expansion or contraction without straining the insulator.
6.3 Space heater shall be provided preferably located near to each insulator to avoid moisture condensation within bus-duct. No and wattage rating of space heater shall be decided by the tenderer.
Insulators. Generally, the type and material of insulators will be selected according to the characteristics of the areas that cross the lines, taking into account the good practices and experiences of transmission lines built in Peru and similar areas. In this sense, the Concessionaire shall investigate those contaminating agents or potential sources of contamination existing in the area and that affect the performance of the insulators. From the results of the investigation indicated shall be determined the measures that reduce the pollution impact. The insulators of the lines shall be evaluated among the types of tempered glass or porcelain, of homogeneous structure, standard type, with metallic parts of forged steel or malleable galvanized iron, provided with locking pins manufactured with corrosion resistant material. The chains of insulators will be composed by the number necessary of units to guarantee a suitable leak length according to the pollution level of the areas where the lines cross, the altitude of them on sea level and the maximum system voltage level. In the same way these chains shall guarantee the isolation level required before lighting overvoltages, operating overvoltages and overvoltages at industrial frequency, for the same conditions of altitude previously indicated and the isolation levels defined in paragraph 2.2 of this annex. The number of insulators to consider per suspension chain, according to the altitude and the voltage level of installations, will be evaluated in the Pre Operability Study. In the case of structures of greater angles, terminals and anchoring the chains shall use one
(01) additional insulator to those used in the suspension chains. The Concessionaire shall establish the technical characteristics of insulators that will be used in the lines, so as to guarantee the adequate isolation levels. In all cases shall be verified that the mechanical resistance of insulators is the adequate, according to the working conditions to which they are submitted,; evaluating, if necessary, the use of double strings or insulators with greater breaking load.
Insulators. 4.1.6.1 Scope
Insulators. Entire area of both sides of spring units to be covered with Perm-a-later wire insulators with a maximum
Insulators. All wires crossing the track shall be supported at each end and each line conductor shall be supported by means of insulator units. The insulator may be of the suspension, tension or pin type as required. All insulator units and their attachments to the conductors shall be capable of supporting the transmission /distribution lines with the factor of safety of not less than three, when any conductor affecting the transmission /distribution lines is broken. Where the transmission /distribution lines is supported by multiple strings of tension or suspension insulators by a common yoke or straddle wires, each insulator unit with its connection shall consist of not less than two separate strings and each strings shall be of such strength that, with one string broken the remaining string or strings shall be capable of withstanding the maximum loads with a factor of safety of three under the worst loading conditions. Where the transmission /distribution lines is supported by pin type insulators in duplicate with a bridle wire, each insulator unit with its connection to the conductor shall have a factor of safety of three under the worst loading condition and with the other unit broken. The use of duplicate conductors bound together across the crossings span shall not be permitted.
