TECHNICAL SPECIFICATION FOR 1.1KV XLPE POWER CABLE SECTION-1

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1 ANNEXURE TO TENDER NO. PUR42396GM DATED 06 th FEBRUARY 2014 SUPPLY OF 1.1KV GRADE LT POWER CABLES FOR THE PERIOD APRIL 2014 MARCH 2016 TECHNICAL SPECIFICATION FOR 1.1KV XLPE POWER CABLE SECTION SCOPE This specification covers design, manufacturing, testing, packing, supply & delivery of 1.1KV XLPE insulated power cables for effectively earthed specification system. 1.2 STANDARDS Unless otherwise specified, the cable shall confirm in all respect to IS7098 (Part 1) -1988, latest amendments till date. 1.3 INSTALLATION CONDITIONS The climatic conditions under which are cables shall operate satisfactory are as follows a. Maximum ambient temperature of air Deg. C 40 0 C

2 b. Maximum relative humidity 96% c. Depth of laying M d. Maximum soil temperature at cable depth 30 C e. Maximum soil thermal resistively 150 C cm/ Watt 1.4 PRINCIPAL PARAMETERS kV (E) Grade XLPE, 3 ½ / 4 -Core, power cable shall be of high conductivity, stranded & compacted, Hard Drawn aluminum sector shaped conductor, with extruded PE compound as insulation which shall be cross linked by Water / Steam curing process. The cores shall be pigmented Red, Yellow and Blue indicating the phase cores while Black pigment shall be used for Neutral core. The four cores shall be laid together and provided with a common covering of extruded PVC inner sheath. Overall galvanized steel strip armour and black pigmented PVC outer sheath to be provided. The specification for manufacturer and testing of cable shall be conforming to IS 7098(Part1) with latest amendments. The cable shall be suitable for laying in ducts and/or buried underground.

3 1.4.4 Cable Parameters Voltage Grade (Uo/U) KV 0.23 / 0.4 Cores (Nos) 3 ½ / 4 System Frequency HZ 50 Maximum allowable temp. of conductor during continuous normal operation at rated full load current. Deg. C 90 Maximum allowable temp. under short circuit condition Deg. C 250 System Earthing Effectively earthed. 1.5 GENERAL TECHNCAL REQUIREMENTS CONDUCTOR The cable conductor shall be made from high conductivity strands of High Density Aluminum conforming to grade H4 to form compacted sector shaped conductor having resistance with in limits specified in IS 8130/1984 and any latest amendments. The compacted conductor shall upon rounding by suitable tools fit snug into the ferrule/ thimble of equivalent size manufactured in line with IS 8308 and IS 8309.

4 1.5.2 INSULATION The insulation shall be fully cross-linked before laying up process. The insulation shall be suitable for 1.1 KV system voltage and should be cross-linked in water / steam curing process. The bidder shall submit the description of curing process, with clear inclusion of equipments / parameters involved. The manufacturing process shall ensure that the insulation shall be free of voids, entrapped moisture bubbles and other foreign inclusions. The insulation shall withstand mechanical and thermal stress under steady state and transient operating conditions. The extrusion method should give very smooth interface with conductor. The insulation of the cable shall be of high standard quality and the thickness of the insulation should be conforming to IS7098 (Part-I) 1988 and its latest amendment FILLER & INNER-SHEATH There shall be no fillers after the sector shaped cores are lapped. However use of plastic binder tape over lapped cores is permissible. The inner sheath shall be extruded. It should be able to withstand the site conditions and the desired operating temperature. It shall be of adequate thickness, consistent quality and free from defects and Black pigmented ARMOUR Armouring should conform to that of formed wire as in IS Galvanized steel strip having suitable radius shall be provided. The

5 armour strips should completely cover the PVC inner sheath, leaving no gaps other than that required for manufacturing. Armour strips should be provided in such a manner that such that cumulative gap between the strips does not exceed the width of one strip. There shall be no armour strip riding over the adjacent strip. The dimensions of strip should conform to Type 1 of IS The mass of Zinc coating shall be 110 gms/m2. The galvanization properties shall conform to those specified in IS OUTER SHEATH Extruded type ST-2 PVC, black colour outer sheath, conforming to IS (or its latest amendment). The minimum thickness of outer sheath should not fall below that specified in IS 7098 Pt (or its latest amendment). The PVC used shall be virgin material CONSTRUCTION All materials used in manufacturing of cable shall be new, unused and of finest quality. All materials should comply with the requirements / test as per applicable IS specification, Indian Electricity Rules and other statutory provision of rules & regulations. CESC Ltd reserves the right to ask for documentary evidence of the purchase of various materials, (to be used for manufacture of cable) as per Quality Assurance plans, to be submitted.

6 1.5.7 CURRENT RATING The current rating shall be based on the maximum conductor temperature of 90 Deg. C with ambient site condition as specified for continuous operation. The de-rating factors should be clearly specified in a tabular form OPERATION Cable shall be suitable for operation under frequency variation of +/-3% and voltage variation +10% to -15% and combined frequency-voltage variation of 10% (absolute sum). Cable shall be suitable for laying in duct or buried underground. These shall be of type & design with proven record on distribution network service LENGTH The cable shall be supplied in standard drum length of 500 / 250 meters, as per delivery specifications from Materials Section of CESC Ltd., with 5% tolerance. Overall tolerance in total quantity of ordered cables shall be +/- 2% IDENTIFICATION MARK The cable drum shall be printed with information as per Cl 21;2 of IS and ISI Certification mark. Bidder shall submit Xerox copy of valid ISI License with technical bid. For identification of cores, Red, Yellow and Blue colours shall be used for identification of phases. Black colour shall be used for Neutral identification. Following details of identification shall be

7 embossed on Outer Sheath at intervals of length of one meter of cable. Name of manufacturer / year of manufacture / voltage grade / cable code / size / name of purchaser (CESC Ltd). Sequential marking of cable length after each meter of cable shall be printed just diametrically opposite side of the above. 1.6 TEST Type Test All cables sizes i.e. items offered should have been fully type tested as per the relevant standards at any Govt. recognized Laboratory.The bidder shall furnish three sets of type test reports along with the offer. The type test reports shall not be older than FIVE years and shall be valid up to the expiry of validity of offer. For any changes in design/type offered against this specification, the purchaser reserves the right to demand repetition of type test without any extra cost. CESC Ltd also reserves the right to have tests carried out at own cost by an independent agency, whenever there is a dispute regarding the quality of supply. Due cognizance is to be given to the report of external agency The following type test reports shall be furnished with the offer a. Test on conductor Tensile test (on wires before stranding). Wrapping test (to be done before stranding ) Conductor resistance test

8 b. Test for armour strips Dimensions test. Physical tests Tensile strength Elongation at break Wrapping test for formed wires Uniformity of zinc coating Mass of zinc coating Resistance test c. Test for thickness of insulation and sheath d. Physical tests for insulation Tensile strength and elongation at break Ageing in air oven Hot set Shrinkage test Water absorption e. Physical tests on outer sheath Tensile strength and elongation at break Ageing in air oven Hot deformation Shrinkage test Loss of mass in air oven Heat shock Thermal Stability

9 f Bending test g Insulation resistance (volume resistivity) test h Heating cycle test i High voltage test Acceptance Test The selection of samples pieces for Acceptance test shall be from 10% drums of each lot offered for inspection or part thereof. The minimum shall be two drums. CESC Ltd reserves the right to conduct acceptance test on more no of sample as per discretion. The following acceptance test shall be carried out on the selected samples as per IS 7098 (Part 1)-1988 Tensile test for aluminum Wrapping test for aluminum strands (before stranding) Conductor resistance test

10 Test for thickness of insulation and sheath Hot set test for insulation. Report of "Hot set Test" to be submitted in each batch. CESC may go to the Manufacturers bay randomly for witnessing the "Hot Set" test, if desired. Tensile strength and elongation at break test for insulation. High voltage test Insulation resistance (volume resistivity) test CESC reserves the right to test the galvanization properties and conduct other physical tests on armour strips All acceptance tests shall be carried out by the bidder, in the presence of representative of CESC Ltd at their works. The bidder shall give at least 15 days advance notice to enable CESC Ltd to depute their engineer for witnessing the tests. The test certificate for acceptance tests witnessed by inspecting officer / engineer shall be submitted for approval before

11 dispatch of material. However, delivery of materials shall be subject to discretion of Materials Section The bidder shall have to submit, well in advance the test certificates of Routine Tests of the complete lot offered for inspection at a time, for our approval prior to inspection. Conductor resistance test; High voltage test. 1.7 STAGE INSPECTION The inspection may be carried out by CESC Ltd at any stage of manufacture. The successful bidder shall grant free access to representative of CESC Ltd at reasonable time, when the work is in progress. Inspection and acceptance, of any cables under this specification by CESC Ltd, shall not prevent subsequent rejection, if the cables are found defective thereafter. The supplier shall keep CESC Ltd informed in advance about the program of manufacturing of cables so that arrangement can be made for inspection. CESC Ltd reserves the right to insist for witnessing the acceptance / routine tests of the bought out items. 1.8 SAMPLING OF CABLES

12 Samples shall be taken and tested from each lot for ascertaining the conformity of the lot to the requirements of the specification. The sampling will be done complying to the conditions as stipulated in Appendix A (Cl. A-3.1) of IS7098 (Part 1) DOCUMENTATION The bidder shall furnish following documents along with his offer. Detailed Quality Assurance Plan related to raw materials, manufacturing process, testing of finished products. Sectional views, showing the General construction feature with conductor / insulation / inner sheath / armouring / and outer sheath along with a detailed GTP as per the annexure enclosed. Drawing of cable drums with details of materials dimension and paint etc shall be submitted. Bidder must submit all the documents related with all the major items of cable, for eg insulation, conductor etc. Bidder must submit all the calculation sheet regarding 1. Short circuit current rating for galvanized steel armour. 2. Continuous current rating considering usual installation conditions. 3. Short time overloading. All the required type test reports for offered items tested at any Government recognized laboratory as stated under clause No Literature, pamphlets for record items. 1.9 PACKING AND FORWARDING

13 The cable shall be wound on wooden drums as per IS and packed in drums suitable for vertical / horizontal transport, as the case may be and shall be suitable to withstand rough handling during transport and outer storage. The outer surface of the drum shall be painted with white aluminum paint. Similarly, the inside surface of drum shall have the coating of varnish to protect it from white ants. The wooden drums shall be reinforced with steel bends and strips for better protection. The ends of the cables shall be sealed by means of application of heat shrinkable tube coated inside with water sealant adhesive. The following information may be stenciled on the drum with either water proof ink or oil paint. 1. Reference of IS standards. 2. Manufacturer s name or trademark. 3. Type of cable and voltage grade. 4. No of cores. 5. Nominal cross section area of Phase conductor. 6. Cable code. 7. Length of cable on the drum. 8. Direction of rotation the drum (by means of an arrow) 9. Position of outer end of cable. 10. Gross weight. 11. Country of manufacture 12. Year of manufacture 13. Property of CESC Ltd. 14. Name of consignee and the destination. Over and above, name plate of aluminum of suitable size and thickness, containing all the above information, shall be fixed on the drum in addition to the painting. The bidder shall be responsible for any damage to the cables during transit due to improper and inadequate packing. Where ever necessary, proper arrangement of lifting hooks shall be provided. Any cable found short inside the packing cases shall be supplied by the supplier, without any extra cost / or as shall be decided Material Section of CESC Ltd.

14 1.10 Each consignment shall be accompanied by a detailed packing list, containing the following information. Name of consignee. Details of consignment. Destination. Total weight of consignment. Handling and unpacking instruction. Bill of materials, including contents of each package. Annexure-I GUARANTEED TECHNICAL PARTICULARS FOR 3 ½ / 4 CORE 1.1 KV XLPE CABLE 1. Name of Manufacturer 2. Country of Manufacture 3. Nomenclature of Cable 4 Size of Cable Phase (mm2) x no. of cores 400 x x 3 ½ 150 x 3 ½ 70 x 3 ½ 25 x 3 ½ 5. Standard according to which cable has been manufactured IS7098 (Part 1) IS7098 (Part 1) IS7098 (Part 1) IS7098 (Part 1) IS7098 (Part 1) 6. Standard according to which cable has been tested. - Do - - Do - - Do - - Do - - Do - 7. Maximum Conductor temperature (a) Continuous (Deg C) (b) Short Time (for 1 Second) (Deg C)

15 8. Conductor (a) Material (b) Grade (c) Nominal Cross- Sectional Area of Phase (Sq. mm) (d) Nominal Cross- Sectional Area of Neutral (Sq. mm) No. of Wires and Diameter (mm) of each Wire (before stranding) for Phase (e) No. of Wires and Diameter (mm) of each Wire (before stranding) for Neutral (f) Shape of Conductor Stranded/ Stranded/ Stranded/ Stranded/ Stranded/ Sector Sector Sector Sector Sector Diameter over Conductor for Phase (mm) (g) Diameter over Conductor for Neutral (mm) 9. Insulation (a) Material (b) Nominal Thickness mm (c) Minimum Thickness mm (d) Diameter over insulation mm (e) Method of curing 10. Extruded Inner Sheath (a) Material and Colour PVC/ PVC/ PVC/ PVC/ PVC/

16 Black Black Black Black Black (b) Average (mm) Thickness 11. Armour Strips ( a ) Material ( b ) Minimum No. of Strips ( c ) Dimensions in mm ( d ) Diameter over armour (mm) 12. PVC Outer Sheath (Type ST2) (a) Colour Black Black Black Black Black Thickness Nominal (in mm) (b) Thickness Minimum (in mm) (c) Cable Marking (i) Embossing At every 1.0 Mtr. Length to contain CESC Ltd, Manufacturer s Name, Type of Cable, Year of Manufacture (i) Sequential Marking of Length At every 1 Mtr length 13. Nominal Overall Diameter of Cable (mm) 14. Nominal Weight / Meter of

17 Cable (Kg / m) 15. Standard Drum Length with Tolerance (Meters) 16. Short Circuit Current Rating of Conductor with maximum conductor temperature (90 C) at the commencement of fault (a) 1 Sec. Duration KA (b) 0.5 Sec. Duration KA (c) 0.1 Sec. Duration KA 17. Minimum Bending Radius for Cable during installation Meters 18. Maximum Continuous Current Rating when installed at a depth of 0.75m, Soil Thermal Resistivity = 150 C Cm/w at Ground Temperature = 30 C, Ambient Temperature = 40 C (a) In Ground Amps (b) In Air Amps (c) In Pipe/ Ducts Amps 19. Electrical Parameters at Maximum Operating Temperature (a) AC Resistance (ohms / Km) (b) Reactance at 50 C/S (ohms/ Km)

18 (c) Impedance (ohms / Km) (d) Approx Cable Capacitance (mfd/ Km) 20. Derating factors for following Ambient Temperature (a) 35 C (b) 40 C (c) 45 C 21. Group derating factor for Cable laid touching / 2D apart Where D = overall diameter of cable (i) 3 Nos. (ii) 4 Nos. (iii) 5 Nos. 22. Test Voltages High Voltage AC at Power Frequency (KV) 23. Details of Drum (a) Material and Weight of Drum (in Kg) (b) Weight of Drum with Cable (in Kg) (c) Flange Diameter of Drum (mtr) (d) Barrel Width of Drum (mtr)

19 (e) Spindle Hole Diameter (mm) NOTE 1. To submit Cross-Sectional Drawing of the Cable specifying the Dimensions in mm. 2. To submit all calculations pertaining to Continuous as well as Short Circuit Current Ratings (for 1 second) of Conductor and Armour