SECTION 7.3 TECHNICAL SPECIFICATION OF POWER CABLES & CONDUCTOR

Transcription

1 SECTION 7.3 TECHNICAL SPECIFICATION OF POWER CABLES & CONDUCTOR 458

2 KV Cables General Where a Manufacturer s Standard or a national Standard equal to or better than the appropriate specified standard has been issued and is acceptable to the Purchaser, any material or goods supplied shall be manufactured, installed and tested in accordance with the latest revision of the relevant standard unless otherwise specified. Where any Standard referred to in this Specification has been superseded by a new standard prior to the date of the letter or invitation to Bid, the reference shall be deemed to be to such superseding standard. Deviations from this Specification or standards referred to above shall be mentioned in the Bid and shall be taken into consideration by the Purchaser before contract placement. The goods shall be designed to ensure continuity of service under all working condition at the site as the first consideration and to facilitate inspection, maintenance and repairs. All electrical components shall be adequately rated for their most onerous duty and the specified ambient temperature References The recommendations and tests specified in the standards shall be adhered to. It shall be the responsibility of the Contractor to demonstrate to the Purchaser that any proposed Standard is equal to or superior to the equivalent IEC or BS. All costs for proving such equivalence are deemed included in the Contractors Bid Prices Climatic Condition The offered XLPE U/G cables with jointing Kits must be suitable for working in the climate conditions of Bangladesh as described below: Altitude : meters above the sea level Maximum ambient temperature : 45 C Minimum ambient temperature : 5 C Humidity : 98 % Mean annual rainfall : mm No. of annual rainy days : days Average isokeraunic level : 80 days/year Pollution of ambient air : dust, salt, chemical. 459

3 General Requirement of 11KV XLPE 2x240 mm 2, 11KV XLPE 3x185 mm 2, 95 mm 2 Copper Cable 11KV, XLPE, 2Cx 240 mm 2 Copper Cable Item No. Description of Items Unit Particulars 1 System Voltage KV 11 2 Rated Voltage KV 6/10(12) 3 Cross sectional Area of Conductors mm 2 2x240 4 Insulation thickness Mm Average thickness shall not be less than 3.40 mm nominal value as per IEC However, thickness at any point may be less than nominal value provided that the difference does not exceed 0.1mm + 10% of nominal value. 5 Manufacturing process Manufactured through VCV/CCV. 6 Conductor Material Copper 7 Shape of Conductor Compact Circular 8 Type of Conductor Screen Semi-conducting XLPE 9 Conductor Temperature at end of short Circuit C 250 Straight-through joint box for 11KV XLPE, 1-Core, 2x240 mm 2 Copper cable Item No. Description of Items Particulars I Application For 11KV, 1-core, XLPE 2x240 mm 2 Copper Conductors Ii Installation For underground horizontal mounting Iii System 11KV, effectively earthed system Iv Cable conductor 2x240 mm 2 1-core, Copper Conductors V Vi Construction Kit content The joint shall be proof against ingress of moisture and water - Compression ferrules - Valid filling tape - Heat shrinkable stress control tubing - Truck resistant sealant tape - Heat shrinkable high voltage insulating tape - Heat shrinkable black/red dual wall - Estomeric tube 460

4 - Roll spring - Heat shrinkable outer jacket tube - Cable preparation kit - Solderless earth connection kit - Misc. other material - Installation instructions Indoor Termination Kits for 11KV, XLPE, 1-Core, 2x240 mm 2 Copper cable I Application For 11KV, 1-core, XLPE 300 mm 2 Copper Conductors Ii Installation For Indoor switchgear terminations Iii System 11KV, effectively earthed system Iv Cable conductor 300 mm 2 1-core, Copper Conductors V Kit content - Heat shrinkable high voltage insulating and nontracking tubing - Heat shrinkable stress control tubing - Stress relieving mastic strip - Truck resistant sealant tape - Cable preparation kit - Solderless earth connection kit - Compression lugs for 2x240 mm 2 Copper Conductors - Installation instructions Outdoor Termination Kits for 11KV, XLPE 2x240 mm 2 Copper cable I Application For 11KV, XLPE 2x240 mm 2 Copper Conductors ii Installation For outdoor installation on poles/structures iii System 11KV, effectively earthed system iv Cable conductor 240 mm 2 2-core Copper Conductors v Kit content - Heat shrinkable high voltage insulating and nontracking tubing - Heat shrinkable stress control tubing - Stress relieving mastic strip - Truck resistant sealant tape - Heat shrinkable truck resistant rain skirt - Support insulator - Cable preparation kit - Solderless earth connection kit - Compression lugs for 500 mm 2 Copper Conductors - Support insulators Tee Brackets - Installation instructions 461

5 11KV, XLPE, 3Cx 185 mm 2 Copper Cable Item No. Description of Items Unit Particulars 1 System Voltage KV 11 2 Rated Voltage KV 6/10(12) 3 Cross sectional Area of Conductors mm Insulation thickness Mm Average thickness shall not be less than 3.40 mm nominal value as per IEC However, thickness at any point may be less than nominal value provided that the difference does not exceed 0.1mm + 10% of nominal value. 5 Manufacturing process Manufactured through VCV/CCV. 6 Conductor Material Copper 7 Shape of Conductor Compact Circular 8 Type of Conductor Screen Semi-conducting XLPE 9 Conductor Temperature at end of short Circuit C 250 Straight-through joint box for 11KV XLPE, 3-Core, 185 mm 2 Copper cable i Application For 11KV, 3-core, XLPE 185 mm 2 Copper Conductors ii Installation For underground horizontal mounting iii System 11KV, effectively earthed system iv Cable conductor 185 mm 2 Copper Conductors v Construction The joint shall be proof against ingress of moisture and water vi Kit content - Compression ferrules - Valid filling tape - Heat shrinkable stress control tubing - Truck resistant sealant tape - Heat shrinkable high voltage insulating tape - Heat shrinkable black/red dual wall - Estomeric tube - Roll spring - Heat shrinkable outer jacket tube - Cable preparation kit - Solderless earth connection kit - Misc. other material 462

6 - Installation instructions Indoor Termination Kits for 11KV XLPE, 3-Core, 185 mm 2 Copper cable i Application For 11KV, 3-core, XLPE 185 mm 2 Copper Conductors ii Installation For Indoor switchgear terminations iii System 11KV, effectively earthed system iv Cable conductor 185 mm 2 Copper Conductors v Kit content - Heat shrinkable high voltage insulating and nontracking tubing - Heat shrinkable stress control tubing - Stress relieving mastic strip - Truck resistant sealant tape - Cable preparation kit - Solderless earth connection kit - Compression lugs for 185 mm 2 Copper Conductors - Installation instructions Outdoor Termination Kits for 11KV XLPE, 3-Core, 185 mm 2 Copper cable i Application For 11KV, 3-core, XLPE 185 mm 2 Copper Conductors ii Installation For outdoor installation on poles/structures iii System 11KV, effectively earthed system iv Cable conductor 185 mm 2 Copper Conductors v Kit content - Heat shrinkable high voltage insulating and nontracking tubing - Heat shrinkable stress control tubing - Stress relieving mastic strip - Truck resistant sealant tape - Heat shrinkable truck resistant rain skirt - Support insulator - Cable preparation kit - Solderless earth connection kit - Compression lugs for 185 mm 2 Copper Conductors - Support insulators Tee Brackets - Installation instructions 463

7 Technical Requirements: Cross Link Polyethylene (XLPE) cables shall be suitable for operation at voltage of 11KV between phases at continuous maximum conductor temperatures of 90 deg. C. The cable shall be suitable in all respect for use on 11KV system with a nominal three-phase fault level of 20KA. The cables and associated fittings, joints and termination shall be so designed to prevent damage to the cable or fittings, except in the immediate vicinity of the fault, in the event of an insulation failure at any point which results in a fault current to earth of 10KA for 1 sec. Each core of Power Cable shall comprise 500sqmm, 400sqmm 300 sq. mm 185 sq.mm. & 150 sqmm Copper Conductor XLPE Insulated, Copper screen and shall comply with IEC 60502, except as modified or extended by the requirement of the specification. The length of cable on a drum shall be 500 Metre continuous or as specified by the Purchaser and it shall be shipped on standard non-returnable steel drum, each drum having stencilled on its side; size, type and length of cable, together with its gross weight, net weight and contract number Conductors All conductors shall be stranded, circular and compacted and comply with IEC Copper conductor cables shall be constructed with three cores of sizes 300 mm sq.mm. & 95 sqmm Conductor Screening The conductor shall be screened with an extruded layer of semi-conducting material of 0.5mm thickness for both the cables Insulation The insulation shall consist of cross-linked polyethylene tightly extruded over the conductor screen. The insulation shall generally comply with IEC The highest possible purity of insulation material is required. The Bider shall confirm that adequate precautions are taken to remove contaminants and to eliminate the introduction of particles of contaminants during material handling or extrusion process. The Cable shall be manufactured through VCV/CCV. The insulation material shall be cross-linked by a dry process. A cross-linking process using steam curing will not be permitted Insulation Thickness The thickness of insulation shall be determined by taking the average of number of measurements and shall be not less than the values tabulated in IEC Publication Insulation thickness shall not depart from the specified nominal value by an amount exceeding the tolerances specified in IEC Publication The thickness at any point, however, is less than the specified value, provided the difference does not exceed 10 percent plus 0.1mm. The thickness of the semi conducting screens on the conductors and over the insulation shall not be included in the measurement of insulation thickness. 464

8 Insulation Screening The insulation screen shall comprise a non-metallic semi-conducting polyethylene part in combination with a metallic part. The non-metallic semi-conducting part shall be applied directly upon insulation of the core and shall comprise a layer of extruded semi-conducting polyethylene compound. The conductor screen, insulation and semi-conducting part of insulation screen layer shall be applied to the conductor in common extrusion process with dry curing system. The metallic part shall be stranded copper applied over the layer of semi conducting compound. There shall be single layer of copper wires adequately spaced apart on each core of Power cable. The non-metallic part shall be applied directly upon the insulation and shall be a layer of extruded semi-conducting compound. This screen shall be formed in such a way that it can be readily removed for jointing. The insulation screen shall be capable of withstanding a fault current of 10KA for 1 sec. without damage Over sheath The cable shall be sheathed overall with a Medium Density Polyethylene (MDPE) outer sheath. The outer sheath shall be of smooth and uniform composition and free of holes, cracks, and bisectors. As a protection against termite attack, the outer covering shall contain the termite repellent substance of Pb napthanate. The outer sheath shall have adequate strength and thickness to withstand the test voltage and mechanical tests and be suitable for ambient conditions at site. The outer sheath material shall be capable of withstanding the highest temperature achieved with the cable at its rated current without damage or deformation at site ambient conditions. The outer surface of the polyethylene outer sheath shall be as specified in IEC Armour The armour shall consist of a single layer of galvanized steel wires in accordance with IEC The joints are brazed or welded and any wire shall be not less than 01 mm from the nearest joints in any other armour wire in the complete cable Continuous Current Rating The continuous current rating of the cable shall be calculated in accordance with the procedure described in IEC based on the site ambient condition, with the insulation parameters as specified. The Cable current ratings shall base on site ambient conditions, with the general methods of installation and bonding. The maximum conductor temperature shall not exceed 90 deg. C when carrying the rated current under the most onerous site conditions. 465

9 Short Circuit Rating The cable shall be capable of withstanding the specified maximum short circuit current for the specified times without damage or permanent distortion. The temperature of the conductor at maximum fault current for the specified time shall not exceed 250 deg. C as specified in IEC Manufacturer Identification The external surface of the cable shall be marked by the following at an interval of 1000 mm with 10mm high character throughout the length of the cable: (i) 11KV, XLPE, Cable size (ii) BPDB, Manufacturers Name mm 2 PVC Copper Cable GENERAL SPECIFICATIONS : These single core cables shall be designed as per above standards and suitable for operation at a maximum voltage of 1000V line to line and suitable for use underground buried in earth or in ducts and above ground in air or in buildings under local ambient conditions. The maximum acceptable length of cable on a drum shall be 500M and shall be supplied on standard non-returnable treated wooden drum, each drum having stenciled on each side: drum number, code name of conductor, drum wound length together with gross and net weight, the manufacturer name, the purchaser's name and contract number with date. The cover of the drum should be of same treated wood. Cable construction shall be as per BS 6004:1994 or equivalent to any internationally acceptable standard. Conductors shall be circular plain annealed copper in accordance with IEC Thickness of insulation shall be in accordance with IEC The over sheath shall be an external layer of black PVC. A means of identifying the cable size and BPDB ownership shall be inscribed throughout the length of the Cable in a single line on the PVC Insulation. The letters shall be upright block characters embossed on the surface; they are being not more than 300 mm between each group. The manufacturer s name with year of manufacture and Progressive Meter Marking shall be provided throughout the length of the cable. Drum wound length of each drum may vary up to ± 5% of the total drum length as tolerance. However, the sum of total drum length shall be as per ordered quantity. Only one short length of conductor on a drum is considered for acceptance, if necessary. For the other requirements, the given data shall be considered as minimum and maximum where necessary. No negative tolerances for the diameter and thickness are acceptable. 466

10 Description Unit Requirements Cable Size mm 2 1CX150 Material PVC Insulated plain annealed copper. Numbers & Diameter of wires No/mm 19/2.52 Maximum resistance at 30 C Ω/KM Nominal thickness of insulation Mm 1.6 Nominal thickness of sheath Mm 1.8 Co lour of sheath Black Approximate outer diameter Mm 19.4 Approximate weight Kg/KM 1129 Continuous permissible service voltage Current rating at 30 C ambient temperature U/G V 600/1000 Amps 270 Current rating at 35 C ambient in air Amps 300 FEATURES AND ACCESSORIES: o Conductors shall be delivered on standard non-returnable strong wooden drum. The central hole of the drum shall be reinforced to fit on axle size 95 mm diameter. The interior of the conductor drum shall be lined with bituminous paper to prevent the conductor from being in contact with timber or Aluminium water proof paper and felt lining shall overlap at seams by at least 20 mm and the seams shall be sealed. o Drum shall be adequately protected by securely fastening substantial wooden battens around the periphery. These battens shall be secured by means of hoop metal bindings. Conductor drum shall be treated in an approved manner to resist termite and fungus attacks and shall be suitable for outside storage for a minimum period of 3 years in an equatorial climate with out undue deterioration. o The PVC covering shall be complete with PVC/A for Insulation and PVC-ST2 for Sheath as per requirement of IEC o There shall be only one length of conductor on a drum. o Treated wooden drum standard: AWPA C 1 82, C 2 83, C 16 82, P

11 mm 2 PVC Copper Cable GENERAL SPECIFICATIONS These single core cables shall be designed as per above standards and suitable for operation at a maximum voltage of 1000V line to line and suitable for use underground buried in earth or in ducts and above ground in air or in buildings under local ambient conditions. The maximum acceptable length of cable on a drum shall be 500M and shall be supplied on standard non-returnable treated wooden drum, each drum having stenciled on each side: drum number, code name of conductor, drum wound length together with gross and net weight, the manufacturer name, the purchaser's name and contract number with date. The cover of the drum should be of same treated wood. Cable construction shall be as per BS 6004:1994 or equivalent to any internationally acceptable standard. Conductors shall be circular plain annealed copper in accordance with IEC Thickness of insulation shall be in accordance with IEC The over sheath shall be an external layer of black PVC. A means of identifying the cable size and BPDB ownership shall be inscribed throughout the length of the Cable in a single line on the PVC Insulation. The letters shall be upright block characters embossed on the surface; they are being not more than 300 mm between each group. The manufacturer s name with year of manufacture and Progressive Meter Marking shall be provided throughout the length of the cable. Drum wound length of each drum may vary up to ± 5% of the total drum length as tolerance. However, the sum of total drum length shall be as per ordered quantity. Only one short length of conductor on a drum is considered for acceptance, if necessary. For the other requirements, the given data shall be considered as minimum and maximum where necessary. No negative tolerances for the diameter and thickness are acceptable. Description Unit Requirements Cable Size mm 2 1CX95 Material PVC Insulated plain annealed copper. Numbers & Diameter of wires No/mm 19/2.52 Maximum resistance at 30 C Ω/KM Nominal thickness of insulation Mm 1.6 Nominal thickness of sheath Mm 1.8 Co lour of sheath Black 468

12 Approximate outer diameter Mm 19.4 Approximate weight Kg/KM 1129 Continuous permissible service voltage V 600/1000 Current rating at 30 C ambient temperature U/G Amps 270 Current rating at 35 C ambient in air Amps 300 FEATURES AND ACCESSORIES: o Conductors shall be delivered on standard non-returnable strong wooden drum. The central hole of the drum shall be reinforced to fit on axle size 95 mm diameter. The interior of the conductor drum shall be lined with bituminous paper to prevent the conductor from being in contact with timber or Aluminium water proof paper and felt lining shall overlap at seams by at least 20 mm and the seams shall be sealed. o Drum shall be adequately protected by securely fastening substantial wooden battens around the periphery. These battens shall be secured by means of hoop metal bindings. Conductor drum shall be treated in an approved manner to resist termite and fungus attacks and shall be suitable for outside storage for a minimum period of 3 years in an equatorial climate with out undue deterioration. o The PVC covering shall be complete with PVC/A for Insulation and PVC-ST2 for Sheath as per requirement of IEC o There shall be only one length of conductor on a drum. o Treated wooden drum standard: AWPA C 1 82, C 2 83, C 16 82, P Technical Specification of ACSR MARTIN GENERAL SPECIFICATIONS: This conductor shall be designed as per above standards for operation in overhead lines in air under local ambient conditions. The conductor shall be constructed from hard drawn Aluminium and Zinc Coated Steel wires where the centre wire or wires are of Zinc Coated Steel and the outer layer or layers are of Aluminium. The wires shall be smooth and free from all imperfections not consistent with good commercial practice. No joint of any kind shall be permitted in the Zinc Coated Steel wires. In all constructions, the successive layers shall have opposite directions of lay, the outermost layer being right handed. The lay ratio of any Aluminium layer shall not be greater than the lay ratio of Aluminum layer immediately beneath it. The lay ratio of different layers shall be within the limit as per above standards. 469

13 The maximum acceptable length of conductor in a drum shall be as stated below and shall be supplied on standard non-returnable treated wooden drum, each drum having stenciled on each side : drum number, code name of conductor, drum wound length together with gross and net weight, the manufacturer's name, the purchaser's name and contract number with date. The cover of the drum should be of same treated wood. Drum wound length of each drum may vary up to ± 5% of the total drum length as tolerance. However, the sum of total drum length shall be as per ordered quantity. Only one short length of conductor on a drum is considered for acceptance, if necessary. For the other requirements, the given data shall be considered as minimum and maximum where necessary. No negative tolerances for the diameter and thickness are acceptable. ACSR MARTIN Code name ACSR MARTIN Installation Overhead Type Stranded Material Hard drawn Aluminum steel reinforced Overall diameter of the conductor mm Nominal cross sectional area of the sq. mm conductor Number/diameter of Aluminum Strand 54/4.02 mm Nominal Aluminum cross sectional area sq. mm Number/diameter of Steel Strand 19/2.41 mm Nominal Steel cross sectional area sq. mm Weight of conductor 2590 Kg/KM Drum wound length 500 M Maximum DC Resistance of Conductor at Ω/Km C Minimum breaking Load of Conductor min Kg Lay direction for Outermost Layer of Right hand Aluminium Rated Strength Min 206 FEATURES AND ACCESSORIES: o o Conductors shall be delivered on standard non-returnable strong wooden drum. The central hole of the drum shall be reinforced to fit on axle size 95 mm diameter. The interior of the conductor drum shall be lined with bituminous paper to prevent the conductor from being in contact with timber or Aluminium water proof paper and felt lining shall overlap at seams by at least 20 mm and the seams shall be sealed. Drum shall be adequately protected by securely fastening substantial wooden battens around the periphery. These battens shall be secured by means of hoop metal bindings. Conductor drum shall be treated in an approved manner to resist termite and fungus attacks and shall be suitable for outside storage for a minimum period of 3 years in an equatorial climate with out undue deterioration. 470

14 o There shall be only one length of conductor on a drum. o Treated wooden drum standard: AWPA C 1 82, C 2 83, C 16 82, P Technical Specification of ACSR Grosbeak SPECIFICATIONS: This conductor shall be designed as per above standards for operation in overhead lines in air under local ambient conditions. The conductor shall be constructed from hard drawn Aluminium and Zinc Coated Steel wires where the centre wire or wires are of Zinc Coated Steel and the outer layer or layers are of Aluminium. The wires shall be smooth and free from all imperfections not consistent with good commercial practice. No joint of any kind shall be permitted in the Zinc Coated Steel wires. In all constructions, the successive layers shall have opposite directions of lay, the outermost layer being right handed. The lay ratio of any Aluminium layer shall not be greater than the lay ratio of Aluminum layer immediately beneath it. The lay ratio of different layers shall be within the limit as per above standards. The maximum acceptable length of conductor in a drum shall be as stated below and shall be supplied on standard non-returnable treated wooden drum, each drum having stenciled on each side : drum number, code name of conductor, drum wound length together with gross and net weight, the manufacturer's name, the purchaser's name and contract number with date. The cover of the drum should be of same treated wood. Drum wound length of each drum may vary up to ± 5% of the total drum length as tolerance. However, the sum of total drum length shall be as per ordered quantity. Only one short length of conductor on a drum is considered for acceptance, if necessary. For the other requirements, the given data shall be considered as minimum and maximum where necessary. No negative tolerances for the diameter and thickness are acceptable. ACSR GROSBEAK Code name ACSR GROSBEAK Installation Overhead Type Stranded Material Hard drawn Aluminum steel reinforced Density of hard drawn Aluminium wire at Kg/dm 3 C Density of Zinc Coated Steel wire at 20 C 7.80 Kg/dm 3 Overall diameter of the conductor mm Nominal cross sectional area of the sq. mm conductor Number/diameter of Aluminum Strand 26/3.97 mm Nominal Aluminum cross sectional area sq. mm 471

15 Number/diameter of Steel Strand 7/3.09 mm Nominal Steel cross sectional area sq. mm Weight of conductor 1304 Kg/KM Drum wound length 500 M Maximum DC Resistance of Conductor at Ω/Km C Minimum breaking Load of Conductor Kg Lay ratio for Outermost Layer of Aluminium Lay direction for Outermost Layer of Right hand Aluminium FEATURES AND ACCESSORIES: o Conductors shall be delivered on standard non-returnable strong wooden drum. The central hole of the drum shall be reinforced to fit on axle size 95 mm diameter. The interior of the conductor drum shall be lined with bituminous paper to prevent the conductor from being in contact with timber or Aluminium water proof paper and felt lining shall overlap at seams by at least 20 mm and the seams shall be sealed. o Drum shall be adequately protected by securely fastening substantial wooden battens around the periphery. These battens shall be secured by means of hoop metal bindings. Conductor drum shall be treated in an approved manner to resist termite and fungus attacks and shall be suitable for outside storage for a minimum period of 3 years in an equatorial climate with out undue deterioration. o There shall be only one length of conductor on a drum. o Treated wooden drum standard: AWPA C 1 82, C 2 83, C 16 82, P