T A B L E T 1 1 of 7 Tests & Inspection Cable PCUT & PCUT-A (Table T1) T E S T S A N D I N S P E C T I O N C A B L E P C U T A N D P C U T - A No. Test Scale MOC Requirements G 20:10:001:01 Defined Test Clause Ref. Method Other Refs a. Tests On Completed Cable Lengths (Manufacturer-100 %) MOC Inspector 10 % Of Drums Of Each Type And 1 2 3 4 Size Of Cable Selection At Random Conductor Resistance at 20 C Resistance Unbalanced at 20 C Conductor Diameter Mutual Conductance 5 Mutual Capacitance 6 7 Capacitance Unbalance Insulation Resistance 5 % of Pairs in each 5 % of Pairs in each 5 % of Pairs in each Conductance Ω/Km max: 0.4 150 0.5 96 0.65 57 0.9 30 Max. 2 % of loop resistance 1 pair of each 2 Micro MΩ/Km 10 % pairs of each 10 % pairs of each layer 5 % of conductance in each 8 Dielectric Strength All tested drums 9 Gas Pressure Test All tested drums 10 11 12 Cable Over all Diameter Identification and Length marker on Sheath Cable End Treatment 13 Cable Drum IEC 28 IEC 344 DC Bridge IEC-708-1 Clause 24 Clause 15.2 Clause 15.3 0.4 to 0.9 mm Direct Measurement Clause 5.2 Max. Av. 55 nf/km Ind. Max. 58 nf/km Per 160 m Length Mean 100 pf Max. 250 pf 10,000 MΩ..Km at 20 C Minimum Between conductors 500 V AC for 3 seconds All conductors and sheath 1500 V AC for 3 seconds Max. leakage 100 g/cm 2 after 12 hours MOC Requirement 1000 Hz at 20 C Clause 5.4 Clause 5.5 /5.3 A to B/A to earth, B to earth with 500 V DC up to 1 min. All other conductors and sheath earthed Clause 5.2 Al conductor bonded together Pressurised at 4 kg/cm² All tested drums See Cable Spec. Direct Measurement All tested drums All completed Drums All completed Drums Type, size, gauge at 1 meter intervals White lettering on sheath i. Valve at inner end ii. Cable banded in red at clockwise (outer) end. Green at inner (anticlockwise) end. iii. Pulling eye Fitted at outer end. 1. Pressure Maintenance at 650 g/cm 2. 2. Sign writing No., length, type, weight etc. Appearance Check Physical Check Pressure Measured and visual checks. Clause 15.7 Clause 15.4 Clause 15.5 Clause 15.6 Clause 15.8 Clause 11.111.2 Table 10 for Clause 11 MOC Common Technical Requirements Clause 17.2 MOC Common Technical Requirements Clause 5.1.7 And 5.2.2 MOC Common Technical Requirements Clause 5.1.2
3. Length verification from sheath marking. And 5.5.2 2 of 7
b. Tests During Manufacture (Random Sampling Tests) 14 15 Conductor Elongation to Break Conductor Tensile Strength 4 tests for each type & size of cable 4 tests for each type & size of cable 16 Jointed Conductor Sample 17 Vacuum Indicator Test 18 Lead Sheath All Lengths All Length Sample 19 Identification Tape Each type of cable 20 21 22 23 24 PE Jacket Tensile Strength 1) Normal 2) After Aging PE Jacket Elongation 1) Normal 2) After Aging Thickness of Insulating Paper Tensile Strength of Insulating Paper Lead Sheath Thickness 25 PE Jacket Thickness 26 Diameter of Finished Cable Core 27 Twinning and lay: 5 samples Dumbbell Test Pieces 5 samples Dumbbell Test Pieces Cond. Minimum 0.4 15 % of length 0.5 15 % of length 0.65 20 % of length 0.9 20 % of length Minimum 20kg/mm² 1) Tensile Strength Min.18 Kg/mm 2 2) Elongation 90 % of un-jointed conductor 3) Resistance 105 % of un-jointed similar length conductor Partial Vacuum Seamless with no joints or cracks Expandable by 50 % Manufacturer s name, type, size, gage at 150 mm intervals 1) Min. 1 Kg/mm 2 2) Max. change 20 % after heating for 48 hours at 100 C 3) Min. 400 % 4) Max. change 25 % after heating for 48 hours at 100 C 3 of 7 Clause 3.3 Length of specimen- 200 mm Jaw Speed ± 20 mm/min. Clause 3.3 ISO R402 1) 250 mm Length sample 2) 250 mm Length sample 3) 150 mm Length sample Measured 12 hours after sealing of cable ends immediately after sheathing Clause 16.1 Clause 16.1 Clause 6.6 Clause 11.11.1 Clause 11.1 Clause 16.13 Physical Check Clause 10 IEC 538 Clause 3 IEC 538 Clause 3 and ASTM D-412 Speed of Jaw separation 350 500 mm/min Clause 16.4.2 Clause 16.4.2 Sample 0.04 mm Minimum Direct Measurement Clause 6.3 Sample Min. 1.8 Kg i.e. 0.07 Kg/µm thickness of paper 25 mm wide 0.25 mm thick test piece Each Cable Type See Specification Direct Measurement Sample of each cable type Sample of each cable type 27.1 Lay of Conductor 27.2 Colour marking & Arrangement of conductors See Specification See Specification Different for adjacent pairs. Max. 200 mm See Specification Visual Direct Measurement Direct Measurement Clause 16.2 Table 8 & 9 Table 10 Table 10 Measured Clause 7 Clause 6.5 Clause 6.7
28 Stranding: 28.1 Formation of Unit Rayon or Cotton Whipping of Layers 1 in Unit No. of Pairs in each 2 layer of Units Helical Paper tape 3 4 5 Lapping of Units Number of Units on Lapping Tape Rayon or Cotton Whipping of Complete Units 6 Stranding of Layer in Units 28.2 Formation Of Cable: 28.2. Whipping of Units in 1 Layers 28.2. Number of Units in 2 Layers 28.2. 3 Core Wrapping 28.2. Colour of Core 4 Wrapping 29 Cables Only: 29.1 Diameter of Steel armouring Wire 29.2 Lay of Steel Armouring Wire Thickness of Steel 29.3 Armouring Tape (If Applicable) 29.4 29.5 29.6 29.7 Overlap of Steel Armouring tapes (If Applicable) Galvanised Coating on Steel Armouring Wire Thickness of Bedding Thickness of Serving Outer Minimum 3 Strands Visual Clause 8.1.2 See Specification Visual Clause 8.1.1 See Specification Visual Clause 8.1.3 At intervals of Max. 50 mm Visual Clause 8.1.3 See Specification Visual Clause 8.1.3 Same Direction for All Layers Visual Clause 8.1.6 See Specification Visual Clause 8.1.8 See Specification Visual Clause 8.1.6 2 Paper Wrappings 0.12 mm thickness 30 % overlap Lead Alloy-E Green Lead Alloy-B Red See Spec Range: 3 6 mm 15 20 times θ Bedding 0.5 1.0 mm See Spec. Visual Clause 9.1 Visual Clause 9.1 Measured Table-8 Measured Clause 12.2.2 Measured Table 10 33 % Measured Clause 12.4.4 Min.: 200 g/m 2 ISO - 1460 Table-5 See Spec. Measured Tables 8&10 See Spec. Measured Tables 8&10 30 Resistivity of Copper Sample 0.017241 Ω at 20 C IEC-28 31 32 Lead Sheath Composition PE Compound Sp. Gravity Each Cable Type Alloy E or B Chemical Analysis Sample 33 PE Carbon Content Sample 34 PE Melt Flow Index Sample Max. 0.5 Medium Density Max. 0.926 0.940 2.5 ± 0.5 (By Weight) IEC-538 Clause 5.1 IEC-538 Clause 5 IEC-538 Appendix (B) Method-C Clause 6.3 Clause 9.3 Clause 10.2 Clause 13.5 4 of 7
35 36 Brittle Temperature Failure Environmental Stress Crack Resistance 5 Specimens at 60 C 10 Specimens after 48 hours conditioning Nil Failure ASTM D-746 Nil Failure at conditioning temperature of 50 C Reagent Igepal CO-630 in 105 Aqueous solution ASTM D1693 See Note-1 on Preparation of Test specimens Note 1 5 of 7
E X P L A N A T O R Y N O T E Tests & Inspection Cable PCUT & PCUT-A (Table T1) 1. NOTE 1: ENVIRONMENTAL STRESS CRACK RESISTANCE TEST 1.1. The test detailed in IEC Publication 538-A Procedure B shall be substituted for that detailed in ASTM D- 1693 when the moulded sheet notch dimensions for medium density polyethylene are determined (See Note in IEC 538- A Sub-Clause 2.6.2) 1.2. The following procedures for the preparation of the moulded sheet for environmental crack resistance tests on PE Sheets are detailed as an aid and clarification to the procedures detailed in ASTM-D-1693. 1.3. Preparation Of Moulded Sheet For Crack Resistance Test (Preparation Of The Mould) 1.3.1. Using a solvent such as trichlaro-ethylene, throughly clean a piece of smooth aluminium foil 230 mm 200 mm. Place this parting sheet on a backing plate of smooth hard aluminium 230 mm 200 mm 6 mm or more thick, having a thermometer well sunk into one edge extending to the centre of the plate. On this is placed a spacing frame consisting of a 230 mm 200 m 3.30 mm thick plate of stainless steel or other suitable material having a rectangular hole 180 m 150 mm with its internal corners rounded to a radius of 3 mm. Place a calculated quantity of polyethylene compound in the opening of the spacing frame in such a way that the material will flow from the centre towards the sides of the frame and avoid leaving bubbles in the moulded sheet. (The approximate quantity of polyethylene required in grams is equal to 27 density thickness (in m) + 2. Cover the charge with a second backing plate also fitted with a thermometer. 1.3.2. Moulding Preheat the press to 170 C. Insert the mould, prepared as above and close the press using light pressure only. Hold until the thermometers indicate that the material has reached a temperature of 165 170 C (Approximately five minutes) and then increase the pressure to a force of 16,000 Kg and maintain it thus for two minutes. Allow the temperature to drop to 340 C in approximately five minutes before releasing the pressure. Remove the backing plates without disturbing the aluminium parting sheets of the frame. This constitutes the annealing. 1.3.3. Annealing Apparatus A circulating-air oven, capable of maintaining a temperature of 145 ± 20 C fitted with a device for lowering the temperature at a constant rate of 5 ± 0.5 C per hour down to at least 400 C. 1.3.4. Separator plates Smooth aluminium plates 230 mm 200 1.5 mm hick. 1.3.5. Follow-Up Plates Smooth aluminium plates 145 mm 170 m 1.6 mm thick. 1.3.6. COVER PLATES A smooth brass plate 230 mm 230 mm 10 mm thick with a thermometer well drilled into one edge and extending to the centre of the plate. Annealing Stack the annealing s horizontally on a shelf or suitable support so as to permit free circulation of air on all sides of the stack as follows: Place a separator plate at the bottom. Centre a follow-up plate plus a separator plate on each. Place the cover plate on top of the stack. The follow-up plates are extended to fit in the depression of the annealing to maintain good contact between the parting sheets and the polyethylene during the expansion on melting and contraction on cooling. After assembling the stack of annealing s in the oven, heat the oven until the thermocouple inserted in the brass cover plates records 145 C. Maintain the oven at 145 ± 2 C/hour, then begin cooling at 5.0 ± 0.50 C/hour by means of a mechanical device. The actual cooling rate should be recorded by a graphical recorder. Remove the annealing s when they have reached 40 C or less, and remove the parting sheets and moulding frames. A properly prepared sheet should contain no bubbles or sink marks except possibly near the edge. Sheets containing such blemishes may be reprocessed at once. 1.3.7. Determination Of Residual Strain Preheat the petri dish containing 3-6 mm of talc to 140 ± 2 C in an air oven. Cut two specimens 13 mm by 38 m from different parts of the test sheet with their long axes perpendicular to each other. Place these specimens on the preheated talc, and maintain at 140 ± 20 C for 30 minutes, then remove the dish with the specimens and allow to cool to room temperature. A specimen that exhibits less than 10 percent shrinkage as measured by a scale readable to 0.1 mm and whose surface remains smooth and regular 6 of 7
indicates a satisfactory test sheet. The outside 6 mm of such sheets should be trimmed and discarded before the sheet is used. 7 of 7