(20) particular specifications - e...

CIDCO OF MAHARASHTRA LIMITED. Sl.Pg.No. 221 C.A.NO. CIDCO/EE(ELECT-S)/2010-2011/85

(20) PARTICULAR SPECIFICATIONS

(ELECTRICAL WORKS)

20.1 GENERAL:

The intent of these specifications is to give general guidelines for the

equipment’s / components proposed to be used and best efforts are

made to cover all relevant requirements and apart intent specification.

However if any addition or alternation is necessitated and directed by

the competent Authority the same shall be done without any extra cost

of financial implication on the CIDCO as per the directives of

Engineer.

20.2 APPLICABLE STANDARDS:

All relevant Indian standards shall be made applicable with latest

amendments. Also if any other specific application is required by the

owners then the same shall be complied too.

ITEM NO. 1 & 2

20.3 SPECIFICATIONS FOR 13 MTRS. & 9 MTRS. RSJ POLES

20.3.1 The pole for H.T. line shall be 152mm x 152 mm rolled steel joist

pole of 13 mtr. height and 9 mtr. height the weight of the pole shall be

minimum of 37.1Kg/Mtr.

20.3.2 A base plate made out of CI and of size 300 mm x 300 mm x 10

mm shall be welded continuously at the pole bottom.

20.3.3 Provision for terminating the earthwire coming from the earthing

station shall be made for the pole at a height of 3.0 mtr. from the

pole bottom with 16 mm dia, 50 mm long G.I. bolt and G.I.

washers.

CIDCO OF MAHARASHTRA LIMITED. Sl.Pg.No. 222 C.A.NO. CIDCO/EE(ELECT-S)/2010-2011/85 20.3.4 The pole shall be erected in a perfectly vertical alignment by

excavating a pit of size 0.8 mtr. x 0.6 mtr. x 2.15 mtr. deep with

1:3:6 ratio cement concrete with duly plastered plinth or muffing of

width 400 mm and height of 600 mm from the ground level and of

appropriate shape. The center to center distance between two

consecutive poles shall be as per the I.E. rules & regulations and local

Electricity Supply Authority.

20.3.5 The poles shall be subjected to surface treatment with wire brushing

and cleaning prior to painting with one coat of red oxide and two

coats of black bituminous paint upto 2.5 mtr. height and for remaining

portion with alluminium paint of two coats.

ITEM NO. 3

20.4 ALUMINUM CONDUCTOR STEEL REINFORCED CONDUCTOR

20.4.1 Scope:

Supply and erection of aluminum conductor steel reinforced for

overhead line.

This specification provides for Supply & Erection of 0.2 ALUMINIUM

CONDUCTOR STEEL REINFORCED (ACSR) Conductor (PANTHER ) for

High Voltage overhead lines.

20.4.2 SERVICE CONDITIONS

The conductor to be supplied against this specification shall be suitable

for satisfactory continuous operation under the following tropical

climatic conditions:

CIDCO OF MAHARASHTRA LIMITED. Sl.Pg.No. 223 C.A.NO. CIDCO/EE(ELECT-S)/2010-2011/85 20.4.3 STANDARDS

Sr.No. Particulars Values

(a) Maximum Ambient Temperature

in open air 50 Degree C.

(b) Maximum Ambient Temperature

in shade 45 Degree C.

(c) Minimum Ambient Temperature

in shade 3.5 Degree C.

(d) Relative Humidity 10 % to100%

(e) Maximum Annual Rainfall 1450 mm.

(f) Maximum Altitude above Mean

Sea level. 1000 metres

(g) Maximum Wind Pressure 150Kg/Sq.m.

(h) Isoceraunic level 50 days/year.

(i) Seismic level

(Horizontal acceleration ) 0.3 g

(j) General nature of climate Moderately hot and

humid tropical climate,

conductive to rust and

fungus growth Except as modified in this Specification, the conductor shall conform to

the following Indian Standards (Amended upto date).

Sr.No. Indian Standards

Title

1 IS:398 Part II

/1996

Specification for Aluminum conductors for

overhead Transmission purpose.

2 IS:1778 /

1980 Reels and Drums for Bare conductors.

3 IS:2629 Recommended practice for Hot Dip

Galvanising of Iron and Steel.

4 IS:4826 Galvanised Coating on Round Steel Wire.


Sr.No. Indian Standards

Title

5 IS:5484 EC grade Aluminium rod produced by

continuous casting and rolling (First

Revision).

20.4.4 PROPERTIES OF CONDUCTOR

The details of ACSR “Panther” conductor are tabulated below:

Sr.No. Particulars Values (a) Stranding and wire

diameter

Aluminium: 30/3.00 mm.,

Steel: 7/3.00 mm.

(b) Number of Strands

(i) Steel Centre 1

(ii) 1st Steel Layer 6

(iii) 1st Aluminium Layer 12

(iv) 2nd Aluminium Layer 18

(c) Sectional area of

Aluminium in sq. mm. 212.1

(d) Sectional area of Steel in

sq. mm. 49.4

(e) Total sectional area in

sq.mm. 261.5

(f) Overall Diameter in mm. 21.00

(g) Approximate weight in

kg/km. 974

(h) Calculated D.C. Resistance

at 20 degree Celsius in

Ohm/km.

0.139

(i) Minimum Breaking load in

kN 89.67

(j) Modulus of Elasticity in

GN/sq.metre. 80.00

CIDCO OF MAHARASHTRA LIMITED. Sl.Pg.No. 225 C.A.NO. CIDCO/EE(ELECT-S)/2010-2011/85 20.4.5 THE DETAILS OF ALUMINIUM STRANDS ARE AS BELOW:

Sr.No. Particulars Values

(a) Minimum Breaking Load of Strand before

stranding in kN

1.17

(b) Minimum Breaking Load of Strand after

stranding in kN.

1.11

(c) Maximum D.C. Resistance of Strand at 20

Degree Celsius in Ohm/km.

4.079

20.4.6 THE DETAILS OF STEEL STRANDS ARE AS BELOW:

WIRE SIZE

Sr.

No. Particulars Values

(a) Minimum Breaking Load of Strand before

stranding in kN. 9.29

(b) Minimum Breaking Load of Strand after

stranding in kN. 8.83

(c) Minimum weight of Zinc Coating after

stranding in gm/sq. Metre. 260

20.4.7 NOMINAL SIZE

The aluminium and galvanised steel wires for the stranded conductor

covered by this standard shall have diameters specified in Clause

20.4.1. The diameter of the galvanized steel wires shall be measured

over the zinc coating.

CIDCO OF MAHARASHTRA LIMITED. Sl.Pg.No. 226 C.A.NO. CIDCO/EE(ELECT-S)/2010-2011/85 20.4.8 TOLERANCE ON NORMAL SIZE

(i) ALUMINIUM WIRES: No negative tolerance shall be permitted

on the nominal diameter of Al wires. However, positive

tolerance in this regards shall be as provided in IS:398 ( part2)

amended upto date.

(ii) GALVANISED STEEL WIRES: A tolerance of +/2 % is permitted

on the nominal diameter.

20.4.9 FREEDOM FROM DEFECTS

The wires shall be smooth and free from all imperfections such as

spills, spilts, slag inclusion, die marks, scratches, fittings, blowholes,

projections, looseness, overlapping of strands, chipping of aluminium

layers etc. and all such other defects which may hamper the

mechanical and electrical properties of the conductor. Special care

should be taken to keep away dirt, grit etc. during stranding.

20.4.10 JOINTS IN WIRES

(i) Aluminium Wires: No joints shall be permitted in the aluminium

wires in the outermost layer of the ACSR conductor. Joints in the

inner layers are permitted, in addition to those made in the

base rod or wire before final drawing, but no two such joints

shall be less than 15 metre apart in the complete stranded

conductor. Such joints shall be made by cold pressure butt-

welding.

Joints are not permitted in the outermost layer of the conductor

in order to ensure a smooth conductor finish.

(ii) Galvanised Steel Wires: There shall be no joints except those in

the base rod or wire before final drawing, in steel wires forming

the core of the steel reinforced aluminium conductor.


Joints are not permitted in the steel wires after final drawing in

order to avoid reduction in the breaking strength of the conduct

or that may occur as a result of failure of the joints.

20.4.11 STRANDING

(i) The wires used in the construction of galvanised steel reinforced

aluminium conductor shall before stranding, satisfy all the

relevant requirements of this specification.

(ii) The lay ratio of the different layers shall be within the limit given

in the following table:

20.4.12 LAY RATIO OF ALUMINIUM CONDUCTORS GALVANISED STEEL

REINFORCED ‘PANTHER’ CONDUCTOR

(1) Number of Wire : Aluminium : 30 Steel : 7

(2) Ratio of Diameter : 1.0

(3) Lay Ratio for Steel Core (6 Wire Layer) : Minimum : 13 Maximum : 28

(4) Lay Ratio for Aluminium Wires:

(i) Outermost Layer : Minimum : 10 Maximum : 14

(ii) Layer immediately beneath outermost Minimum: 10 Layer: Maximum: 16

NOTE: For the purpose of calculation, the mean lay ratio shall be taken as the

arithmetic mean of the relevant minimum and maximum values given

in the above table.

(iii) While stranding, pre forming and post forming method should be used for

stranded steel core. In order to relieve the residual tension in core wire to

avoid flaring of conductor.

(iv) In all constructions, the successive layers shall have opposite directions of lay,

the outermost layer being righthanded. The wires in each layer shall be

evenly and closely stranded.

CIDCO OF MAHARASHTRA LIMITED. Sl.Pg.No. 228 C.A.NO. CIDCO/EE(ELECT-S)/2010-2011/85 (v) In conductors having multiple layers of aluminium wires, the layratio of any

aluminium layer shall not be greater than the layratio of aluminium layer

immediately beneath it.

Table 20.4/1

Minimum Clearance between Conductors

(IS : 4237 – 1967)

Clearance in mm Sr. No.

Voltage Level (kN) Between Phases

Between Phase & Earth

7. 11 460 305

8. 22 610 460

9. 33 915 610

10. 110 1675 1000

11. 230 3350 1675

12. 400 4000 3500

20.4.13 The conductor shall be Panther alluminium conductor steel reinforced

and size as specified & with generally having current carrying capacity

of 325 amps. of 40 degree centigrade and consisting of a bunch of

six/ seven stranded alluminium conductors and one steel reinforcing

wire at the center. The weight of the conductor shall be 974Kg/Km.

20.4.14 The conductor shall generally conform to I.S. 398 Part-II - 1976 with

latest amendments.

20.4.15 STRINGING OF CONDUCTORS:

a) Peels of the conductor shall be handled carefully so that there is

no cutting, nicking of fraying of the conductor strands.

b) The conductor shall be paid out from a rotating red supported

on jacks for easy unwinding.


c) Alluminium sheaves fitted with ball bearings shall be used at the

points of conductor supports for easy pulling and to ensure

uniform tension throughout the conductor length.

d) The conductor shall be pulled with proper care along clamp.

e) The conductor should be pulled up to a proper sag in a span at

or near the dead end section of the line.

f) The tension should then be adjusted until correct sag is obtained

in a span near the pulling end.

g) Generally in straight length cut points shall be provided at a

distance of about 1 Km. or as desired by MSEB/CIDCO.

h) The minimum clearances from the conductor shall be as per

rule `17 to 79’ and 80 of I.E. Rules.

20.4.16 a) Annealed alluminium wire shall be used for fastening the

conductors.

b) The anticlimbing device consisting of barbed wire extending

upto a minimum length of 38 cms. or any other suitable design

shall be provided on all H.T. poles.

c) The danger or caution sign board to be displayed on all H.T.

Poles shall be as per I.S. 2551 - 1963.

d) All stay wires are required to be properly earthed.

e) At all road crossing points guard wires are required to be

used as per rule No.88 of I.E. rules.

20.4.17 Method of Construction :

At first the conductor is removed from bundle / drum straighten

without knots, bends, etc.

Stringing of conductor shall be done with draw vice. Conductor shall

not be twisted while stringing. Disc insulators shall be used if the line


deviates by 30 degrees or more, terminal pole and tri-pole or four

pole structure at terminal pole and at junction / cut pole.

Parallel double groove clamp having two nut bolts designated to carry

full line current shall be used for making Jumper wire connections.

Universal parallel double groove clamp having two nut bolts shall be

used for Tap Off point.

On straight line the conductor shall be bounded on top groove of

insulator and at angular position binding shall be done in side groove.

Binding wire of 12 SWG shall be of the same metal as that of

conductor.

20.4.18 Mode of Measurement :

For measurement purpose, sum of the total conductor including

jumper connections shall be considered. (i.e. per km)

ITEM NO. : 4

20.5 PIN TYPE INSULATOR 11/22/33 KV

20.5.1 Scope:

Supplying porcelain Pin type insulator, suitable for 11/22/33 Kv and

necessary ancillary materials and complete erection on provided cross

arm / bracket and connected to the over-head line as per instructions

from the site engineer.

Material :

Insulator : Distribution class Pin type insulator made from porcelain,

suitable for specified voltage level, having ISI mark, with necessary

hardware

Hardware: Nuts, washers. Etc.

Binding Wire : Bare Copper wire or conductor.

Clamps : MS Clamps.

CIDCO OF MAHARASHTRA LIMITED. Sl.Pg.No. 231 C.A.NO. CIDCO/EE(ELECT-S)/2010-2011/85 20.5.2 General

a) All the insulators shall be made out of glazed porcelain or

rough glass and suitable for 22KV line voltage.

b) The pin insulators shall generally be as per I.S. 731-1963 and

the disc insulators shall be generally as per I.S. 731 – 1963 and

I.S. 3188 – 1965 with all latest amendments.

c) 4.3 The manufacturer’s dimensional drawings should be

submitted for pin type insulator.

d) Providing suitable size tension hardware made out of cast

alluminium suitable ACSR conductors etc. complete. The work

should be carried out as per instructions of the Engineer.


Distribution class porcelain pin type insulator, suitable for specified

voltage level, erected on provided cross arm or bracket with clamps,

ancillary materials, and connected to the over-head line. Connection

shall be made with bare copper wire of specified gauge.


Executed quantity will be measured on number basis (i.e. each)

ITEM NO. : 5

20.6 PORCELAIN DISC. TYPE INSULATOR 11/22/33 KV

Supplying and erecting porcelain disc type insulator suitable for 22KV

line complete erected with suitable hardware on provided cross arm

20.6.1 Scope:

Supplying porcelain disc type insulator, suitable for 11/22/33 KV and

necessary ancillary materials, and complete erection on provided cross

arm / bracket and connected to the over-head line as per instructions



Material:

Insulator: Distribution class Disc type insulator made from porcelain,

suitable for specified for specified voltage level, having ISI mark, with

necessary hardware.

Hardware: Nuts, washers, etc.

Binding Wire: Bare Copper wire or conductor.

Clamps: MS clamps.

20.6.2 Method of construction:

Distribution class Disc type insulator made from porcelain, suitable for

specified voltage level, erected on provided cross arm or bracket with

clamps, ancillary materials, and connected to the over-head line.

Connection shall be made with bare copper wire of specified guage.

20.6.3 Mode of Measurement:


ITEM NO. : 6 & 7

20.7 PLATE TYPE EARTHING

(WITH OR WITHOUT CI COVER, FUNNEL, ETC)

20.7.1 Scope

Supplying and erecting galvanised cast iron / copper earth plate type /

G.I. pipe type earthing with / without C.I. cover as per instructions


Material:

Earth Plate: Galvanised cast iron / Copper earth plate or G.I. pipe as

per specifications given in Table No 20.7/1.

CI Cover: As per specifications given in Table No 20.7/1.

Earthing Conductor: Copper/G.I strip/Annealed bare copper wire/G.I.

earth wire of size as per specifications given in Table No 20.7/1.


GI Pipe: As per specification (CW-PLB/GP) mentioned chapter no.

20.7/1.5 for watering, and as enclosure for Earth wire, refer

specifications given in Table No 20.7/1.

Hardware: Screw / nut bolts with required washer of dimensions, Rawl

plug / clip/ 'U' nails and material as per specifications given in Table

No 20.7/1.

Filling material: Coal /Charcoal/ salt as per specifications given in

Table No 20.7/1.1.

Lugs: As per specification (CB-LG/AL, CB-LG/CU) mentioned chapter

20.7/1.9 & 20.7/1.10 Copper/ Aluminum lugs as per specifications

given in Table No 20.7/1.

Table No. 20.7/1

Detailed Specifications of various types of Earthing

Type of earthing

S.

No. Particulars

Galvanised

cast iron

earth plate

type without

C. I. cover

Copper

earth plate

type with

C. I. cover

Galvanised

cast iron

earth plate

type with

C. I. cover

Pipe type

earthing

without C. I.

Cover

1. Depth from top of

plate

Up to Ground level

1.5 m

Galvanised 1.5 m

1.5 m

Galvanised -

2. Size & type of

material for pipe /

Plate type earthing

Cast iron

earth plate

size

60x60x0.6

cms

Copper

earth plate

size

60x60x0.6

cms

Cast iron

earth plate

size

60x60x0.6

cms

‘B’ grade

G. I. pipe

40 mm dia.

2.5 mtr.

Long or 20

mm dia. G.

I. Rod

3. Salt / Charcoal 30 Kg.

charcoal

and slat

30 Kg.

charcoal

and salt

40 Kg.

charcoal

and salt

N.A.


Type of earthing

S.

No. Particulars

Galvanised

cast iron

earth plate

type without

C. I. cover

Copper

earth plate

type with

C. I. cover

Galvanised

cast iron

earth plate

type with

C. I. cover

Pipe type

earthing

without C. I.

Cover

each each each

4. Type of Wire Double G.I.

wire 8 SWG

Double G.I.

8 SWG

Double G.I.

6 SWG

Double G.I.

8 SWG

5. Wire enclosure 12 mm dia.

G. I. Pipe 2

mtr. long

12 mm dia.

G. I. Pipe 2

mtr. long

12 mm dia.

G. I. Pipe

2.5 mtr.

long

N.A.

6. Nut bolts 12 mm dia.

Cadmium /

GI

12 mm dia. Cadmium / N.A.

7. Washers GI GI GI N.A.

8. Watering Pipe 19 mm dia.

G. I. Pipe

19 mm dia.

G. I. Pipe

19 mm dia.

G. I. Pipe N.A.

9. Lungs Yes Yes Yes Yes

10. Funnel No Yes Yes N.A.

11. Brick Masonry No Yes Yes N.A.

20.7.2 Method of construction: Pit is' to be dug of required dimension and depth for the earthing at

site, and laying of Galvanised cast iron / Copper earth plate or G.I.

pipe shall be as per Table No 20.7/1. The earth connection to

equipment / switch gear and earthing electrode shall be connected as

shown in the diagram and as per IS 3043 amender up to-date. The

connections shall be made either by strip or double run of earth wire


with drilling, welding, riveting, brazing and nut bolting to plate or

pipe, where ever required in an approved manner. As far as possible

continuous strip shall be used, but where ever jointing of strip is

unavoidable; the overlap portion must not be less than 21/2 times the

width of the strip either welded/ brazed/soldered by all sides or 6

inches overlap with two nut bolts/riveting of adequate size with

requited washer and covered by anti-corrosive paint as per approved

jointing practice in the industry and as per directives from site engineer

in charge.

Pit shall then be filled with screened soil with alternate layer of coal

and3alt, and if, necessary brick masonry work (Where ever applicable)

shall be done as specified in IS: 3043, with laying wires in PVC/ G.I.

pipe and watering arrangement and covered with C.I. Cover (Where

ever applicable). .

Where ever required or as specified by Site Engineer, a Test link shall

be provided for facilitating the testing of resistance of earth electrode.

20.7.3 Testing:

The value of each earth electrode shall be measured by earth tester in

presence of site Engineer and record to be submitted.

20.7.4 Mode of Measurement:


ITEM NO. : 8

20.8 Providing cement Concrete for Foundation or for concrete filling in

1:3:6 ratio with 20 to 25 mm stone metal duly plastered with

necessary curing for pole muffing or any other purpose.

The work should be carried out as per the instructions of the Engineer.

And payment will be made as mentioned in Schedule “A.

CIDCO OF MAHARASHTRA LIMITED. Sl.Pg.No. 236 C.A.NO. CIDCO/EE(ELECT-S)/2010-2011/85 ITEM NO. : 9

20.9 VEE CROSS ARM

20.9.1 Scope :

Supplying Vee cross arm suitable for 22 kV and necessary ancillary

materials complete erection on provided pole with necessary painting

as per specification and as per instructions from the site engineer.

Material :

Cross arm : Channel Iron cross arm

Hardware : G. I. nut bolts

Flat : MS flat 80 x 10 mm thick

Clamp : Two clamps made from MS flat of size 80 x 10 mm.

Paint : Red oxide, Silver paint


Fabricating the Vee cross arm for erecting Insulators with channel 75 x

40 mm with 4.4 mm thick web and 7.3 mm thick flange, length of 45

mm for base of insulator, vertical member of suitable length to

maintain the clearance of 1530 mm, with angle of 60 degrees to

horizontal and M. S. flat of 80 x 10 mm. at centre of cross arm fixed to

the pole by means of two M. S. clamps of 80 x 10 mm M. S. flat with

15mm. dia bolts and nuts duly painted with one coat of red oxide

paint and two coats of aluminum paint.

Table No. 9/1

DETAILS OF IRON CROSS ARM / BRACKET AS PER ITEM IN CSR

Item

description Size of channel Clamps Nut bolts

100x50

channel cross

arm

100x50 mm with 4.7 mm

thick web and 7.5 mm thick

flange channel x 2.7 m length

Two clamps

of 50x6 mm

M. S. flat

15 mm. nuts and

bolts


Item

description Size of channel Clamps Nut bolts

Vee-cross

arm

Made out of channel 75 x 40

mm with 4.4 mm thick web

and 7.3 mm thick flange with

clearance of 1220 mm.

between the insulators as per

drawing attached here with

Clamps for

75x10 mm of

M. S. flat

15 mm. nuts and

bolts

Vee-cross arm 100x50 mm with 4.7 mm

thick web and 7.5 mm thick

web and 7.5 mm thick flange

size suitable with clearance of

1530 mm between the

insulators

Clamps for

75x10 mm of

M. S. flat

15 mm. nuts and

bolts

Channel with

clamp for

erection for

11/22 KV pin

insulators

75x40 mm with 4.4 mm thick

web and 7.3 mm thick flange

channel.

Clamps for

75x10 mm of

M. S. flat

with 3 sets screws

Channel

bracket for

guarding

Channel iron 1600 mm in

length and 75x40 mm with

4.4 mm thick web and 7.3

mm thick flange

Clamps for

50x6 mm of

M. S. flat

15 mm. dia nuts

and bolts with 2

earthing clips,

made from 25x3

mm.

Angle iron

bracket for

guarding

Angle iron bracket 65 x 65 x

6 mm. Angle 1600 mm in

length and 75x40 mm with

4.4 mm thick web and 7.3

mm thick flange.

Clamps for

50x6 mm of

M. S. flat

15 mm. dia nuts

and bolts with 2

earthing clips,

made from 25x3

mm.



CIDCO OF MAHARASHTRA LIMITED. Sl.Pg.No. 238 C.A.NO. CIDCO/EE(ELECT-S)/2010-2011/85 ITEM NO. : 10

20.10 Supplying & Erecting G.I strip of different size used other purpose with

necessary G.I clamps fixed on wall painted with bituminous paint is an

approved manner.


And payment will be made as mentioned in Schedule “A.

ITEM NO. : 11

20.11 22 KV DANGER BOARD:

Providing & fixing G.I Caution board fabricated from 16SWG sheet of

size 200 x 150 mm (min). The board shall be written in Marathi &

English indicating pressure of line danger etc. as required Electricity

Rules & Regulation and as per IS: 2551 of 1982.

Contractor has to provide to provide 22KV danger board one number

on each pole of appropriate size and with proper signals with

appropriate painting with approved colours as per IE rules.

ITEM NO. : 12

20.12 H.T. STAY SET:

Supplying and erecting G.I stay set for poles, complete with anchor

plate 300x300x6mm straining screws G.I stay wire 7/8 SWG G.I stay

rod 20mm x 1.8 meter length and pole clamps duly erected in

provided cement concrete foundation.

20.12.1. G.I Stay set for poles including loop insulators at in-accessible height

complete with anchor plate of size 15 x 15 x 0.6 cms, straining

screws, G.I Stay wire 7/10 size, G.I. Stay rod 20mm x 1.8 M long and

pole clamps etc. Stay sets erected in 1:3:6 cement concrete

foundation approx. quantity 0.35 m3 for each set.

CIDCO OF MAHARASHTRA LIMITED. Sl.Pg.No. 239 C.A.NO. CIDCO/EE(ELECT-S)/2010-2011/85 20.12.2 Providing G.I. stay wire for poles of appropriate thickness and length

suitable for H.T. line. The work should be carried out as per the

instructions of the Engineere.

20.12.3 Providing binding wire for binding the G.I. stay wire of the poles

suitable for H.T. overhead line of appropriate tensile strength &

thickness. The work should be carried out as per the instructions of the

Engineer.

20.12.4 Supplying and erecting anticlimbing devices, fabricated from pole

clamps with dropping spikes, welded to it and erected on pole

properly. The work should be carried out as per the instructions of the

Engineer.

20.12.5 Providing cement concrete foundation for above poles of size 0.8 mtr.

x 0.6 mtr. x 2.15 mtr. deep with 1:3:6 cement concrete ratio with duly

plastered plinth/muffing or width 400mm. & height of 600 mm. from

the ground level with appropriate shape. The plastering should be

done with approved quality cement with proper curing etc. complete.


ITEM NO. 13

20.13 Preparation of schematic & detailed drawings as required by statutory

Authority and submission of the same in required sets to the statutory

authority on behalf of CIDCO, obtaining the approval for

commencement and commissioning of the work. Payment of statutory

authority, co-ordination with authority for the site visits etc. and

submission of As Built Drawings in 3 sets in the form of prints and in

the form of CD. The work also includes obtaining approvals of

material, handing over of the installation to the statutory authority on

completion of the work under the guidance of Engineer. And payment

will be made as mentioned in Schedule “A”.

CIDCO OF MAHARASHTRA LIMITED. Sl.Pg.No. 240 C.A.NO. CIDCO/EE(ELECT-S)/2010-2011/85 Item

No. Description

20.14 Supplying & erecting anticlimbing devices, fabricated from pole clamps with

drooping spikes welded to it and erected on pole.

20.15 Excavating hard rock or bituminous rod (B.T) by chiseling for preparing pit for

poles stay or earth plates or for laying cables, pipes & clearing the site by

removing debris & making the site good.

20.16 Supplying and erecting approved make 22KV out door type gang operated

air break triple pole switch 200 amperes capacity with 3post pin type

insulator per phase mounted in horizontal or vertical position with necessary

channels on provided cross arm with adequate length of 'C' class G.I pipe for

operating handle erected on extended square shaft. The operating handle

provided with lock and key at suitable height from ground level with

necessary clamp.

20.17 Supplying and erecting approved make thyrite type lightening arresters

suitable for 22KV supply with necessary ancillary materials complete erected

on provided cross arm and connected to the overhead line Distribution Class.

20.18 Supplying erecting approved make 22KV outdoor type drop out fuse with

insulator complete with fuse holder fuse barrel with metal fitting fuse element

mounted on MS channel with working current of 10A capacity complete

erected on provided cross arm

20.19 Supplying and laying (including excavation ) 15 cms. Dia full round RCC

hume pipe with coupling collar of standard thickness at required depth upto

90 cms. Below road /ground surface, for enclosing provided cable and

necessary back filling with light ramming to make the road / ground surface

as it was ( except bitumen carpet)

20.20 Providing & laying 75mm dia G.I pipe 'B' grade for enclosing cable below

ground / road surface complete.

The work should be carried out as per the instructions of the Engineer. And payment

will be made as mentioned in Schedule “A.

CIDCO OF MAHARASHTRA LIMITED. Sl.Pg.No. 241 C.A.NO. CIDCO/EE(ELECT-S)/2010-2011/85 ITEM NO. 21 & 22

20.21 TECHNICAL SPECIFICATIONS FOR 22KV/11KV XLPE CABLE

SCOPE

This technical specification covers design, manufacture, testing at

manufacturer’s works, packing & delivery of High Voltage Cross linked

polyethylene insulated PVC Sheathed cables round armoured suitable

for 11 KV and 22KV.

It is not the intent to specify completely herein all the details of design

& construction of the cables. However the cables shall conform to high

standards of engineering, design & workman ship. The equipment

offered shall be complete with all components necessary for its

effective and trouble free operation.

STANDARDS

Unless otherwise specified elsewhere in its specification, the rating,

performance and testing of cables & accessories shall conform to the

latest revision of all relevant standards.

A list of such standards is enclosed at ANNEXURE – I.

20.21.1 PRINCIPAL PARAMETERS

The high Voltage Cables and accessories covered in this specification

shall meet the technical requirements listed at ANNEXURE – II and the

following general technical requirement.

20.21.2 GENERAL TECHNICAL REQUIREMENT

Conductor

20.21.2.1 The conductor shall be made from electrically pure Aluminium wire.

The wires shall be stranded together and compacted.

CIDCO OF MAHARASHTRA LIMITED. Sl.Pg.No. 242 C.A.NO. CIDCO/EE(ELECT-S)/2010-2011/85 20.21.2.2 The conductor shall be circular in shape.

20.21.3 Conductor Shielding

An extruded semi conducting compound shall be provided on the

conductor to provide a smooth surface & eliminate electrical stress

concentration.

20.21.4 Insulation

The core insulation shall be with Cross linked polyethylene unfilled

insulation compound. It shall be free from voids and shall withstand all

mechanical and thermal stresses under steady state & transient

operating conditions. The insulation shall be applied by triple extrusion

process.

20.21.5 Insulation Shielding

The insulation shielding shall consist of non-metallic semi-conducting

compound in combination with non-metallic screening of copper. It

shall be possible to strip the insulation screening without applying

heat. The screen shall be capable to carry single line to ground fault

current for a duration of one second.

20.21.6 The conductor screen and XLPE insulation screen shall all be extruded

in one operation by extrusion to ensure perfect bonding.

20.21.7 Armouring

G.I. round steel wire armouring shall be provided over the inner

sheath.

20.21.8 Outer Sheath

An outer sheath shall be applied on the cable by extrusion over

armouring. The outer sheath shall be of PVC compound confirming to

Type ST2. The PVC compound shall be suitable for protection against

rodent and termite attack.

CIDCO OF MAHARASHTRA LIMITED. Sl.Pg.No. 243 C.A.NO. CIDCO/EE(ELECT-S)/2010-2011/85 20.21.9 In addition to the above, binder tape, filler, core identification tape

shall be provided.

ANNEXURE-I

22KV/11KV XLPE CABLE APPLICABLE STANDARDS

The cables shall comply with the latest edition of the following standards:

Sr. No.

Indian Standard

Spec. No.

Title

1. IS 7098 (Part-II) Cross-linked Polyethylene insulated PVC

sheathed cables : Part II for working voltages

form 3.3KV upto and including 33KV.

2. IS:8130 Conductors for insulated electric cables and

flexible cords.

3. IS:5831 PVC insulation and sheath of electrical cables.

4. IS:3975 Mild steel wires, strips and tapes for

armouring of cables.

5. IS:2633 Methods of testing weight, thickness and

uniformity of coating on hot dipped

galvanized articles.

6. IS:209 Specification for Zinc

7. IS:1753 Aluminium conductors for insulated cables.

8. IEC:502 Extruded solid dielectric insulated power

cables for rated voltages form 11KV upto 30

KV.


Sr. No.

Indian Standard

Spec. No.

Title

9. IEC:540 & 540A Test methods for insulation and sheaths of

electric cables and cords.

ANNEXURE-II

22KV/11KV XLPE CABLES

DESIRED TECHNICAL PARTICULARS

Sr. No.

Description Unit 11kV Particulars 22kV Particulars

1. Cable Size Core x Sq.mm.

Upto 3C x 300 & 1C x 1000

sq.mm.

31C x 300 sq.mm.

2. System Voltage kV 11 22

3. Type of cable XLPE Insulated XLPE Insulated

4. Conductor material Aluminium Aluminium

5. Minimum No. of

strands

No. 30 37

6. Nominal thickness of

XLPE insulation

mm 3.6 6.00 mm

7. Minimum thickness of

common covering

mm 0.7 0.7mm

8. Armouring - round mm 3.15 mm dia 4mm dia

9. Minimum thickness of

outer sheath

mm 2.84 3.00

10. Approximate overall

diameter

mm 81 87.5

11. Approximate net

weight

kg/km 10400 13850


Sr. No.

Description Unit 11kV Particulars 22kV Particulars

12. Normal Delivery

Length

m 250 250

13. Max. DC Resistance at

20 deg C

Ohms/km 0.1 As per IS 7098

Paer-II

14. Approximate AC

Resistance

Ohms/km 0.13 0.130

15. Approximate

reactance at 50 Hz.

Ohms/km 0.095 0.97

16. Approximate

Capacitance per

phase

Mfd/km 0.475 0.319

17. Current rating Amps 355 (in ground)

450 (in air

350 (in ground)

455 (in air

18. Short time current

rating

kA 28.2 28.3

19. Permissible short

circuit temperature

Deg.C 250 250

ITEM NO. 23

20.23 CABLE TRENCHES (EXCAVATED):

20.23.1 The cable trenches shall be excavated 1000 mm below the finished

ground level and shall have a minimum width of 300 mm. for laying

of single cable. When more than one cables are laid in the same

trench, the width of the trench shall be increased such that the spacing

between the cables is 25 cms. and the end cables are at minimum 15

cms. from the side of the trenches. At the turning of the cable route

the trench shall be dug with radius equal to 15 times the cable

diameter.


20.23.2 The trenches shall be cut square with vertical side walls and with

uniform depth. Suitable shoring and propping may be done to avoid

caving in of trench walls. The floor of the trench shall be rammed and

leveled. The bottom of the cable trench shall be prepared with

100mm. sand bed for laying the cables.

20.23.3 The cables shall be laid in trenches over the rollers. After the cable is

laid and straightened it shall be covered with sand, and RCC half

round/semi circular pipe of appropriate strength & size.

20.23.4 The cable trench then shall be refilled with excavated materials after

removing the stones and other sharp materials and the refilled

materials shall be compacted with light ramming.

20.23.5 Approved cable markers made of G.I. with 15 cms crown shall be

provided along the route of cables at a spacing of 40 – 50 meters and

also at both ends of road crossings or at the cable turning points. The

class, type and No. of cables shall be indicated on the markers.

20.23.6 Cable shall be laid in hume pipes at all road crossings and in GI pipes

at the wall entries.

ITEM NO. 24

20.24.0 Outdoor/Indoor end termination Kit : LT/HT Cables

Before providing end termination kit to the cable, the cable end of the

equivalent length of the moulds, shall be prepared by removing the

outer PVC insulation along with the steel armouring. The ferrule shall

then be inserted over the bare core of the cable, and shall be crimped

with hydraulic / mechanical type heavy duty crimping tool. The

crimping shall be done in such a manner that there shall be no air

gap. Then the crimped portion shall be wrapped first with the PVC


insulation tape and then with the insulation tape used for wrapping HT

conductor. The above method shall be carried out for all the cores

strictly using the epoxy spacer, for having sufficient gap in-between the

leads. The earth continuity lead shall be clamped to theends of the

cable. After covering the cable leads with the PVC moulds, the edges

shall be clipped after applying the adhesive on the inside face of the

epoxy compound shall not spill out. Now the duly stirred epoxy

compound shall be poured and fill till the compound rises through the

risers provided on the moulds.

After completing the above procedure, the joint shall be allowed to dry

out for at least 8 to 10 hours (for epoxy compound to get hardened)

depending upon the size of cable. Before connecting to supply, the dry

and hardened joint shall be tested for its insulation level with 1000 V/

5000 V Meggar.

ITEM NO. 25

20.25 Straight through joint Kit: L T/HT Cables

Before providing joint to the cable, the cable ends of the

equivalent length of the joint moulds, shall be prepared by removing

the outer PVC insulation along with the steel armouring. The ferrule

shall then be inserted over the bare core of the cable, and shall be

crimped with hydraulic I mechanical type heavy duty crimping tool.

The crimped portion shall be wrapped first with the PVC insulation

tape and then with the insulation tape used for wrapping HT

conductor. The above method shall be carried out for all the cores

strictly following the colour code. The leads of the both the cables now

shall be placed into the mould by using the epoxy spacer, for having

sufficient gap in-between the leads. The earth continuity lead shall be


clamped to the both ends of the cable. After covering the cable leads

with the PVC moulds, the edges shall be clipped after applying the

adhesive on the inside face of the moulds. The pasting of moulds shall

be rigid and as far as possible leak proof, so that the epoxy compound

shall not spill out. Now the duly stirred epoxy compound shall be

poured and fill till the compound rises through the risers provided on

the moulds.

After completing the above procedure, the joint shall be allowed to

dry out for at least 8 to 10 hours (for epoxy compound to get

hardened) depending upon the size of cable. Before connecting to

supply, the dry and hardened joint shall be tested for its insulation

level with 1000 VI 5000 V Meggar.

The cable should be fixed or laid in such manner that there should

not be pressure on end of moulds or on jointing position of cables.

Signature of Tenderer

Date.:

Chief Engineer & General Manager(T)

Date :

(20) particular specifications - e...

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