DMRC Electrical Standards & Design Wing - Delhi...

DMRC Electrical Standards & Design Wing DMES-E/0006

SPECIFICATIONS FOR MEDIUM VOLTAGE CABLE FOR ELEVATED STATIONS - SUPPLY & INSTALLATION

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DELHI METRO RAIL CORPORATION LIMITED

DMRC ELECTRICAL STANDARDS & DESIGN WING (DESDW)

SPECIFICATION NO.

DMES- /E/0006/DMRC-E-E&M-MV CABLES-01

SPECIFICATIONS FOR MEDIUM VOLTAGE CABLE FOR ELEVATED STATIONS - SUPPLY AND

INSTALLATION

Issued on:

Date Stage

30 March 2015 Draft-1

DELHI METRO RAIL CORPORATION LTD.

7th Floor, B-Wing, Metro Bhawan, Fire Brigade Lane,

Barakhamba Road, New Delhi –110 001



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Previous Record of specification

Stage Date

Draft -1 30-Mar-15



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Table of Content 1.1 Scope ................................................................................................................................................. 4

1.2 Standards .......................................................................................................................................... 4

1.3 Abbreviations .................................................................................................................................... 5

1.4 Technical Requirements .................................................................................................................... 6

1.4.1 PVC Cables ......................................................................................................................................... 6

1.4.2 XLPE Cables........................................................................................................................................ 6

1.5 Delivery, Storage and Handling ......................................................................................................... 6

1.6 Installation ........................................................................................................................................ 7

1.6.11 Cables laid in Masonry Trenches....................................................................................................... 8

1.6.12 Cable laid On Trays/Walls ................................................................................................................. 8

1.6.13 Buried Directly in Ground ................................................................................................................. 9

1.6.14 Routing of the Cable Runs. ................................................................................................................ 9

1.6.15 Width of Trench .............................................................................................................................. 10

1.6.16 Depth of Trench .............................................................................................................................. 10

1.6.17 Excavation of Trenches in Ground .................................................................................................. 10

1.6.18 Laying Of Cable in Trench in Ground .............................................................................................. 11

1.6.19 Route Markers................................................................................................................................. 12

1.6.20 Laying In Pipes / Closed Ducts ......................................................................................................... 13

1.6.21 Laying Of Cables in Floors ............................................................................................................... 13

1.6.22 Cable Entry into Buildings ............................................................................................................... 13

1.6.23 Cable Joints ..................................................................................................................................... 14

1.6.24 Cable Loops ..................................................................................................................................... 14

1.6.25 Termination / Jointing Of Cables .................................................................................................... 14

1.7 Material and Manufacturing ........................................................................................................... 14

1.8 Testing ............................................................................................................................................. 15

1.8.3 Testing at Site .................................................................................................................................. 15

1.8.6 Acceptance test report for XLPE cables at ANNEXURE A1 .............................................................. 16

1.8.7 Acceptance test report for PVC cables at ANNEXURE A2 ............................................................... 17

1.8.8 ANNEXURE B .................................................................................................................................... 18



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1.1 Scope

1.1.1 The Medium Voltage cables are used at an elevated station of the Delhi Metro for E & M

applications for power supply and control for various equipment.

1.1.2 This specification takes care of the design, manufacturing, testing and installation

requirements of the Cables. There are two types of cables namely PVC insulated as per

IS: 1554 (Part-1):1988 and XLPE insulated PVC sheathed as per IS 7098 (Part-1): 1988.

XLPE cables are generally used for power supply application and PVC insulated for

control application.

1.2 Standards

1.2.1 All equipment, components, materials and entire work shall be carried out in conformity

with applicable and relevant IS/BS/IEC Standards and Codes of Practice. In addition,

relevant clause of Indian Electricity Act 2003 and Indian Electricity Rule 1956 amended

up to date shall apply.

1.2.2 It is to be noted that updated and current standards shall be applicable irrespective of

the dates mentioned along with standards in the tender document.

IS 1554 (Part-I) – 1988 PVC insulated (heavy duty) electric cables: Part 1 For working voltages up to and including 1100 V

IS 7098 (Part-l) – 1988 Cross-linked polyethylene insulated PVC sheathed cables: Part 1 For working voltage up to and including 1100 V

IS 1255 – 1983 Code of practice for installation and maintenance of power cables up to and including a 33 KV rating

IS 8130 – 1984 Conductors for insulated electric cables and flexible cords

IS 10418 – 1982 Drums for electric cables

IS 10810 Methods of test for cables (All latest)

IS 3961 Recommended current rating for cables (All latest)

IS 5819 – 1970 Recommended short circuit rating of high voltage PVC cables

IS 5831 PVC insulation and sheath of electric cables.

BS 7671 – 2008 Requirements for electrical installations. lET Wiring Regulations - Sixteenth edition.

1.2.3 Cables up to size 10-sqmm conductor size shall be copper conductor & beyond size 10-

sqmm shall be aluminium. All conductors shall be stranded



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1.3 Abbreviations

S. No. Abbreviation Description

1. PVC Poly-vinyl Chloride

2. XLPE Cross-Linked Polyethylene

3. FRLSH Flame Retardant Low Smoke and Halogen

4. LV Low Voltage

5. MV Medium Voltage

6. HV High Voltage

7. HT High Tension

8. MS Mild Steel

9. GI Galvanized Iron

10. RCC Reinforced Cement Concrete

11. UPVC Unplasticised Poly Vinyl Chloride



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1.4 Technical Requirements

1.4.1 PVC Cables

1.4.1.1 Medium voltage cables shall be 1100 Volt grade aluminium/copper conductors, PVC

insulated, PVC sheathed with flame retardant low smoke and halogen (FRLSH)

compound and armoured conforming to IS: 1554 Part-l. Cables shall be rated for 1100

Volts.

1.4.1.2 The insulation shall be of Type A PVC compound conforming to the requirements of IS

5831.

1.4.1.3 The conductor of all cables shall be stranded. Sector shaped stranded conductors shall

be used for cables of 50-sqmm and above.

1.4.2 XLPE Cables

1.4.2.1 The cables shall be 1100 Volt grade XLPE insulated with PVC inner sheath, steel

armouring and with an outer protective sheath of flame retardant low smoke and

halogen(FRLSH) compound, conforming to IS: 7098 (Part I). Cables shall have high

conductivity stranded aluminium or copper conductors and cores colour coded to the

Indian Standards.

1.4.2.2 A common covering (bedding) shall be applied over the laid up cores by an extruded

sheath of unvulcanised compound. Armouring shall be applied over this extruded

sheath. The outer sheath shall bear the manufacturer's name and trade mark at every

meter length. Cores shall be provided with following colour scheme of PVC insulation

1 Core: Red / Black/Yellow/ Blue

2 Core: Red and Black

3 Core: Red, Yellow and Blue

3 ½ /4 Core: Red, Yellow, Blue and Black

1.4.2.3 The colour of the outer sheath shall be Black or as required by the Engineer.

1.5 Delivery, Storage and Handling

1.5.1 Storage and handling shall conform to section 7 of IS 1255.

1.5.2 All cables shall be new without any kinks or damage, marked with DMRC,

manufacturer's name, insulating material, conductor size and voltage class on cable

surface at every 1000 mm approx.



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1.5.3 Cable drum conforming to IS: 10418 shall be stored on a well-drained, well-ventilated

area protected from sun and rain on hard surface, preferably of concrete, so that the

drums do not sink in ground causing rot and damage to the cable drum.

1.5.4 For transportation over long distance, the drums shall either be mounted on drum

wheels, trailers and pulled by ropes, unloaded preferably by crane and rolled down

carefully on suitable ramps. While transferring cable form one drum to another, the

barrel of the new drum shall have diameter not less than the original drum

1.6 Installation

1.6.1 While shortest practicable route shall be preferred, cable runs shall follow fixed

development such as roads, footpaths etc. with proper offsets so that future

maintenance and identification are rendered easy.

1.6.2 Whenever cables are laid along well demarcated or established roads, the LV/MV cables

shall be laid further from the line than HV cables.

1.6.3 Cables of different voltages and also power and control cable shall be kept in different

trenches with adequate separation. Where available space is restricted, LV/MV cables

shall be laid above HV cables.

1.6.4 Where cables cross one another, the cables of higher voltage shall be laid at a lower

level than the cables of lower voltage.

1.6.5 Power and communication cables shall as far as possible, cross at right angles, where

power cables are laid in proximity to communication cables the horizontal and vertical

clearances shall not normally be less than 600 mm.

1.6.6 Cables shall be laid in the routes marked in the drawings. Where the route is not

marked, the contractor shall mark it out on the working drawings after deciding in

consultation with Engineer. Cables shall be laid in masonry trenches, directly on walls /

ceiling, inside shafts / cable trays, directly buried in ground or in pipes/ducts as

elaborated below. Cables of different voltages and also power and control cables shall

be laid, in different trenches with adequate separation. Wherever available space is

restricted such that this requirement cannot be met, medium voltage cables shall be laid

above HT cables as approved.

1.6.7 Single cables laid shall be fixed directly to walls or ceiling and supported at not more

than 600 mm. Cables laid in built-up trenches shall be on GI supports.



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1.6.8 Cables shall be so laid that the maximum bending radius is 12 times the overall diameter

of the cable for medium voltage cables and 15 times the overall diameter for 11 kV

cables or in accordance with the manufacturer's recommendations whichever is higher.

1.6.9 In the case of cables buried directly in ground, the cable route shall be parallel or

perpendicular to roadways, walls etc. Cables shall be laid in an excavated, graded

trench, over a sand or soft earth cushion to provide protection against abrasion. Cables

shall be protected with brick or cement tiles as shown on Drawings. Width of excavated

trenches shall be as per code of practice and drawings.

1.6.10 The general arrangement of cable laying shall be as per drawings. All cables shall be full

runs from panel to panel without any joints or splices.

1.6.11 Cables laid in Masonry Trenches

1.6.11.1 Wherever so specified, cables shall be laid in indoor/outdoor masonry/RCC trenches

with chequered plate/RCC covers to be provided by contractor. Cables shall be laid on GI

supports of approved design grouted in trench walls at intervals not exceeding 600 mm.

If required, cables shall be arranged in tier formation inside the trench. Cables shall be

dressed properly so that the clear spacing between the cables shall not be less than the

diameter of the cable. Suitable clamps, hooks and saddles shall be used for securing the

cables in position. Complete details of this support work shall be shown in working

drawings to be prepared by the Contractors and submitted for approval of Engineer

before execution. Works shall be carried out only as per approved working drawing.

Wherever so specified, trenches shall be filled with fine sand.

1.6.12 Cable laid On Trays/Walls

1.6.12.1 Where numbers of cables are run, necessary perforated cable trays shall be provided

wherever shown. Ladder cable trays shall be galvanized MS as specified in the BOQ.

1.6.12.2 After laying and securing the cables in a cut-out, suitable water tight sealant shall be

applied as per requirement to prevent any ingress of water.

1.6.12.3 Cables shall be secured in position and dressed properly by means of suitable clamps,

hooks, saddles etc. Clamping of cables shall be at minimum intervals as below:



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Type of Cables Size Clamping by Fixing intervals

MV Up to and including 25-sqmm

Purpose made, approved GI clamp minimum 2 mm thick 19 mm wide

300 mm

MV&HV 35-sqmm to 120-sqmm

Clamps 3 mm thick 25 mm - wide

600 mm

MV&HV 150-sqmm and above

Clamps 3 mm thick 40 mm - Wide

600 mm

Note: The fixing intervals specified apply to straight runs. In the case of bends, additional clamping shall be provided at 30 cm from the centre of the bends on both sides.

1.6.13 Buried Directly in Ground

1.6.13.1 Cables should be so laid that they will not interfere with underground structures.

1.6.13.2 All water pipes, sewage lines or other structures which become exposed by excavation

shall be properly supported and protected from injury until the filling has been rammed

solidly in places under and around them. Cables shall be laid and protected at such

locations.

1.6.13.3 Any telephone or other cables coming in the way are to be properly shielded as directed

by Engineer.

1.6.13.4 Surface of the ground shall be made good so as to conform in all respects to the

surrounding ground to the satisfaction of Engineer.

1.6.14 Routing of the Cable Runs.

1.6.14.1 Before cable laying work is undertaken, the route of the cables shall be decided in

consultation with Engineer.

1.6.14.2 While shortest practicable route shall be preferred, cable runs shall follow fixed

development such as roads, footpaths etc. with proper offsets so that future

maintenance and identification are rendered easy.

1.6.14.3 Whenever cables are laid along well demarcated or established roads, the LV/MV cables

shall be laid further from the kerb line than HV cables.



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1.6.14.4 Cables of different voltages and also power and control cables shall be kept in different

trenches with adequate separation. Where available space is restricted, LV/MV cables

shall be laid above HV cables.

1.6.14.5 Where cables cross one another, the cables of higher voltage shall be laid at a lower

level than the cables of lower voltage.

1.6.14.6 Power and communication cables shall as far as possible cross at right angles. Where

power cables are laid in proximity to communications cables the horizontal and vertical

clearances shall not normally be less than 600 mm

1.6.15 Width of Trench

1.6.15.1 The width of trench shall be determined on the following basis:

(a) The minimum width of masonry trench for laying single cables shall be 350 mm or as

specified in BOQ.

(b) Where more than one cable is to be laid in the same trench in horizontal formation,

the width of trench shall be increased such that the inter-axial spacing between the

cables except where otherwise specified shall be at least one cable diameter.

1.6.15.2 There shall be a clearance of at least 150 mm between axis of the end cables and the

sides of the trench.

1.6.15.3 The space between multiple cables laid in same trench shall be laid as prescribed by the

manufacturer of the cable or as recommended in standards.

1.6.16 Depth of Trench

1.6.16.1 Where cables are laid in single tier formation, in ground the total depth of the trench

shall not-be less than 750 mm for cables up to 1.1 kV and 1250 mm for cables above 1.1

kV. When more than one tier of cables is unavoidable and vertical formation of laying is

adopted, the depth of trench shall be increased by 300 mm for each additional tier to be

formed.

1.6.17 Excavation of Trenches in Ground

1.6.17.1 The trenches shall be excavated in reasonably straight lines. Wherever .there is a change

in direction, suitable curvature of 12 times the overall diameter of the largest MV cable

and 15 times the overall diameter for 11·kV HT cable shall be provided. Where gradients

and changes in depths are unavoidable, these shall be gradual. Excavation should be

done by any suitable manual or mechanical means. Excavated soil shall be stacked firmly

by the side of the trench such that it may not fall back into the trench.



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1.6.17.2 Adequate precautions shall be taken not to damage any existing cables, pipes or other

such installations during excavation. Wherever bricks, tiles or protected covers or bare

cables are encountered, further excavation shall not be carried out without the approval

of the Engineer. The Contractor shall use a cable detector along the route of excavation

and identify existing live cables along the route and exercise caution during excavation.

1.6.17.3 Existing property exposed during trenching shall be temporarily supported or propped

adequately as directed by the Engineer. The trenching in such cases shall be done in

short lengths, necessary pipes laid for passing cables therein and the trench refilled as

required. If there is any danger of a trench collapsing or endangering adjacent

structures, the sides shall be well shored up with timbering and / or sheathing as the

excavation proceeds. Where necessary these may even be left in place when backfilling

the trench.

1.6.17.4 Excavation through lawns shall be done in consultation with the Engineer. Bottom of the

trench shall be level and free from stone, brick, etc. The trench shall be provided with a

layer of dean dry sand cushion of not less than 80 mm in depth before laying of cables.

1.6.18 Laying Of Cable in Trench in Ground

1.6.18.1 The cable drum shall be properly mounted on jacks or on a cable wheel at a suitable

location. It should be ensured that the spindle, jack etc. are strong enough to carry the

weight of the drum without failure and that the spindle is horizontal in the bearing so as

to prevent the drum creeping to one side while rotating.

1.6.18.2 The cable shall be pulled over rollers in the trench steadily and uniformly without jerks

or strains. The entire cable length shall, as far as possible, be laid in one stretch.

However when this is not possible the remainder of the cable shall be removed by

flaking i.e. making one long loop in the reverse direction.

1.6.18.3 After the cable is uncoiled and laid over the rollers, the cable shall be lifted slightly over

the rollers beginning from one end by helpers standing about 10 meters apart and

drawn straight. The cable should then be taken off the rollers by additional helpers

lifting the cables and then laid in the trench in a reasonably straight line.

1.6.18.4 For short runs and cable sizes up to 50-sqmm 1.1 kV grade, the alternative method of

direct handling can be adopted with the prior approval of the Engineer. If two or more

cables are laid in the same trench, care should be taken to preserve relative position. All

the cables following the same routes shalt be laid in the same trench. Cables shall not

cross each other as far as possible. When the cable has been properly straightened, the

cores shall be tested for continuity and insulation resistance. The cable shalt be

measured thereafter.



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1.6.18.5 Suitable moisture sealing compound tape shall be used for sealing of the ends of cables

laid in the trench. All the cables remaining in drums after laying shall be sealed in a dust

and moisture proof manner.

1.6.18.6 The trench shall be provided with a layer of clean dry sand cushion of not less than 80

mm in depth before laying of cables. Cable laid in trenches in a single tier formation

shall have a covering of clean dry sand of not less than 170 mm above the base cushion

of sand before the protective cover is laid. If additional tiers are formed each of the

subsequent tiers also shall have a sand cushion of 300 mm and the top most cable shall

have a final sand covering not less than 170 mm before the protective cover is laid. A

final protection to cables shall be laid to provide warning to future excavators of the

presence of the cable and also to protect the cables against accidental mechanical

damage. Such protection shall be with second class bricks of not less than 225 mm x 100

mm x75 mm (normal standard size) laid breadth wise for the full length of the cable to

the satisfaction of the Engineer. Where more than one cable is to be laid in the same

trench this protective covering shall cover all the cables and project at least 50 mm over

the sides of the end cables. In addition bricks on edge shall be placed along the entire

run on either side of the cable run.

1.6.18.7 The trenches shall then be back filled with excavated earth free from stones or other

sharp edged debris and shall be rammed and watered in successive layers not exceeding

300 mm. Unless otherwise specified a crown of earth not less than 50 mm in the center

and tapering towards the side of the trench shall be left to allow for subsidence. The

crown of earth should however not exceed 100 mm so as not to be a hazard to vehicular

traffic.

1.6.18.8 Where road berms or lawns have been cut or kerbstones displaced the same shall be

repaired and made good to the satisfaction of the Engineer and all surplus earth and

rocks removed to places as specified.

1.6.19 Route Markers

1.6.19.1 Route markers shall be provided along straight runs of the cables at locations approved

and generally at intervals not exceeding 25 meters. Markers shall also be provided to

identify change in the direction of the cable route and also for location of every

underground joint.

1.6.19.2 Route markers shall be made out of 100mm x 100mm x 5mm GI/aluminium plate

welded or bolted onto 35 mm x 35 mm x 6 mm angle iron 600 mm long duly painted

with anti-corrosive paint/ embossed. Such plate markers shall be mounted parallel to

and 300.mm or so away from the edge of the trench/pipe/duct, or as directed at site.



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1.6.19.3 Markers shall be embedded in cement concrete 1:2:4 (one cement, 2 coarse sand: 4

graded stone aggregate of 30 mm normal size). The word "Cable" and other details such

as voltage grading, size etc. as required shall be painted on the marker.

1.6.19.4 Identification tags

Plastic identification tags shall be provided at every 30m. Cables shall be identified at

end terminations indicating the feeder number and the Panel/Distribution board from

where it is being laid.

1.6.20 Laying In Pipes / Closed Ducts

1.6.20.1 In locations such as road crossings, entry to buildings/ poles in paved areas etc. cables

shall be laid in pipes or closed ducts. Spun reinforced concrete/GI pipes or UPVC ducts

shall be used for such purposes and the pipe shall not be less than 100 mm in diameter

for a single cable and not less than 150 mm for more than one cable. These pipes shall

be laid directly in ground without any special bed. Unless otherwise specified the top

surface of pipes shall be at a minimum depth of 1000 mm from the ground level when

laid under roads, pavements etc.

1.6.20.2 The pipes for road crossings shall preferably be on the skew to reduce the angle of bend

as the cable enters and leaves the crossing. Pipes shall be continuous and clear of debris

or concrete before cable is drawn. Sharp edges at ends shall be smoothened to prevent

injury to cable insulation or sheathing.

1.6.21 Laying Of Cables in Floors

1.6.21.1 Laying of cables directly in floors shall be avoided and GI pipes of adequate size shall be

used wherever necessary. However if the cables have to be laid direct in the floor

specific written approval of shall be obtained and the Contractor shall cut chases, lay

the cables and make good the chases to original finish.

1.6.22 Cable Entry into Buildings

1.6.22.1 Cable entry into buildings shall be made through RCC pipes recessed in the floor. RCC

Hume pipes shall be provided well in advance for service cable entries. The pipe shall be

filled with sand and sealed at both ends with bitumen mastic to avoid entry of water.

Suitable size manholes shall be provided wherever required to facilitate drawing of

cables as per requirements. The Contractor shall submit a written request to Engineer

for inspection of following works for cabling:

On excavation and provision of sand bed at bottom of trench

On laying of cables, and provision of sand bed over the cables



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On provision of protective cover & back filling

On commencing termination of cable

These requests shall be serially numbered and shall be in an approved format out of one

or two formats to be submitted by the Contractor.

1.6.23 Cable Joints

1.6.23.1 Cable joints shall be resorted to and permitted only if length of cable route is more than

standard cable drum length. Cable joints shall not be permitted in any other

circumstances. Wherever unavoidable these joints shall be made with specific approval

of Engineer, and shall from a part of cable run /laying. Cable Jointing shall be done only

of approved make cable joints. No extra cost shall be paid for jointing of cables.

1.6.24 Cable Loops

1.6.24.1 At the time of the installation approximately 3 meters of surplus cable shall be left .as

below or as directed by Engineer-In-charge

at each end of the cable

on each side of underground straight through/tee/termination joints

at entries to buildings

This cable shall be left in the form of a loop.

1.6.24.2 Wherever long runs of cable length are installed cable loops shall be left at suitable

intervals as specified by the architect/clients.

1.6.25 Termination / Jointing Of Cables

1.6.25.1 All cable terminations should be nut-bolt type; irrespective of the cable size and shall

have tinned copper compression lugs. The end terminations shall be insulated with a

minimum of six half-lapped layers of PVC tape. Cable armouring shall be bonded at both

ends.

1.6.25.2 Soldered jointing/ termination shall be totally avoided. Solder-less terminations by using

crimping tools, suitable lugs and double compression brass glands shall be used. In the

case of aluminium conductors, it is to be ensured that the conductor oxidation is

cleaned by means of emery paper and then a thin coat of tin is applied before

termination.

1.7 Material and Manufacturing



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1.7.1 The material used in the manufacturing shall not deviate from the one used in the

manufacturing of sample piece of which the type test results submitted for vendor

approval.

1.7.2 The routine and acceptance test result shall not vary widely as compared to the type

test results.

1.7.3 The manufacturers shall be able to demonstrate to the inspecting official the sourcing of

material and process as per the system described in ISO document for continuous

quality control.

1.8 Testing

1.8.1 Type test results as per the relevant standards mentioned herewith and not more than

one year old shall be submitted along with the vendor approval request. In case the

vender so desires, a repeat of the type test from the accredited lab may be asked for.

1.8.1.1 FRLSH, PVC insulated Cables shall be subjected to type tests and acceptance test as per

IS: 1554 Part-1 1988 carried out in accordance with appropriate parts of IS: 10810.

1.8.1.2 FRLSH, XLPE cables shall be tested as per IS: 7098 Part-1 and IS: 10810.

1.8.2 The acceptance test for XLPE and PVC shall be carried as per the proforma given at

annexure A1 and A2 respectively. The prescribed values as per relevant IS and type

results as available on record shall preferably filled by inspecting official before the

inspection.

1.8.3 Testing at Site

1.8.3.1 The test at site after receipt and installation shall be carried as per the proforma given at

annexure B.

1.8.4 All type, acceptance and site test readings records shall form part of the completion

documentation.

1.8.5 Underground Cable routes shall be got verified with the help of cable detector.



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1.8.6 ANNEXURE A1

Acceptance test report for XLPE cables:

Specified Values Type Test Values

Unit

(Specified Values shall

be as per IS 7098 Pt-1

and the Cable selected)

Type test Values shall

be the same as

submitted at the time

of Vendor approval

Red, Yellow, Blue & Black Red, Yellow, Blue & Black Red Yellow Blue Black

Black/Black Black/Black

-

i) Thickness (Main) mm

(Neutral) mm

ii) Thickness of Inner Sheath mm

iii) Thickness of Outer Sheath mm

iv) Overall Dia of Cable mm

-

i)No. of Wires in Conductor (Class-

2)(M/N)-

ii)Conductore Resistance at 20 oC

(M/N)Ohm/Km

iii) Tensile strength (Before ageing) N/mm2

iv) Wraping Test (Before ageing) -

v) Annealing Test (Before stranding) %

-

i) a) Volume resistivity (at 27 oC) Ohm cm

b) Volume resistivity (at 90 oC) Ohm cm

ii) a) Tensile strength (Before ageing) N/mm2

b) Elongation at break (Before

ageing)%

iii)Hot set test (at 200+ 3 oC for 15

min.)-

a) Elongation under load %

b) Permanent Elongation %

-

i) Strip Dimension mm

-

i) a) Tensile strength (Before ageing) N/mm2


ageing)%

-

i)High Voltage Test ( for each

connection)-

i) Embossing over outer Sheath

ii)Sequential Length Marking at every

meters

(Manufacturer) (Contractor)

Date and Signature:

(DMRC Inspecting officer)

Acceptance Test ReportCustomer Name:

P.O. No. & Date:

Description:

Specification: IS 7098 Pt-1 & Data Sheet Observed Values

S.

No.

Test Descriptions DRUM No.:

Core Idenditification

Colour of Inner Sheath & Outer Sheath Black/Black

1

Dimentional Check

2

Tests on Conductor (As per IS 8130)

3

Test on Insulation (As per IS-7098-1)

7

Visual Inspection

4Test on Armouring (as per IS- 3875)

5

Test on Outer Sheath (as per IS- 5831)

6

Test on Complete Cable



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1.8.7 ANNEXURE A2

Acceptance test report for PVC cables:

Specified Values Type Test Values

Unit

(Specified Values shall

be as per IS 1554 Pt-1

and the Cable

selected)

Type test Values shall

be the same as

submitted at the time

of Vendor approval

Red, Yellow, Blue & Black Red, Yellow, Blue & Black Red Yellow Blue Black

Black/Black Black/Black

-

i) Thickness (Main) mm

(Neutral) mm

ii) Thickness of Inner Sheath mm

iii) Thickness of Outer Sheath mm

iv) Overall Dia of Cable mm

-

i)No. of Wires in Conductor (Class-

2)(M/N)-

ii)Conductore Resistance at 20 oC

(M/N)

Ohm/K

m

iii) Tensile strength (Before ageing) N/mm2

iv) Wraping Test (Before ageing) -

v) Annealing Test (Before stranding) %

-

i) a) Volume resistivity (at 27 oC) Ohm cm

b) Volume resistivity (at 90 oC) Ohm cm

ii) a) Tensile strength (Before ageing) N/mm2


ageing)%

iii) Hot set test (at 200+ 3 oC for 15 min.) -

a) Elongation under load %

b) Permanent Elongation %

-

i) Strip Dimension mm

-

i) a) Tensile strength (Before ageing) N/mm2


ageing)%

-

i)High Voltage Test ( for each

connection)-

i) Embossing over outer Sheath

ii)Sequential Length Marking at every

meters

(Manufacturer) (Contractor)

Date and Signature:

(DMRC Inspecting officer)

Visual Inspection

Test on Insulation (As per IS-1554-1)

1

2

3

4

5

6

7

Dimentional Check

Tests on Conductor (As per IS 8130)

Test on Armouring (as per IS- 3875)

Test on Outer Sheath (as per IS- 5831)

Test on Complete Cable

Black/Black

Acceptance Test ReportCustomer Name:

P.O. No. & Date:

Description:

Colour of Inner Sheath & Outer Sheath

Specification: IS 1554 Pt-1 & Data Sheet Observed Values

DRUM No.:Test DescriptionsS.

No.

Core Idenditification



Draft-1

18

1.8.8 ANNEXURE B

Cable Installation Checklist 1 Insulation Resistance(500 V)

(in MΩ)

R-Y

Y-B

B-R

R-N

Y-N

B-N

R-PE

Y-PE

B-PE

N-PE

2 Continuity

Yes/No

R

Y

B

N

PE

3 Visual Inspection

Yes/No or Remarks

a. No cracks and physical damage observed on cable

b. Proper hook, clamp and saddle provided as per spec.

c. Bending radius as per specification and provision of additional

support at bends

d. Proper offsets and loop provided for future maintenance

e. Proper distance maintained between the control and LV cables

f. Proper Phase sequence

g. Armour of the cable earthed properly at both ends

h. Route Marker provided as per specification

i. Distance between the LV/MV and HV cables, if exists together

j. Identification tags provided as per specification

k. Cable termination has been completed as per the specification

l. Underground cable routes verified with the help of cable detector

Checked

By(Contractor) Verified By(DMRC)

DMRC Electrical Standards & Design Wing - Delhi...

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