1

HIMCHAL PRADESH STATE ELECTRICITY BOARD LIMITED ( A State Govt. Undertaking)

“NOTICE INVITING TENDER”

Sealed item rate tenders are herby invited on behalf of the Chairman cum

Managing Director HPSEB Ltd. by the undersigned from the approved / experienced contractor of

appropriate category for the execution of works as per the detail of works mentioned hereinafter.

The tenders shall be received on prescribed forms clearly super -scribed with Tender No. and Date

of opening together with earnest money in the office of Superintending Engineer, Operation

Circle, HPSEB Ltd. Solan, on stipulated date and time & will be opened in the presence of the

contractors or their authorized representatives who may wish to be present.

The tender document can be had on any working day during 11:00 AM to 5:00

PM w.e.f 1.06.2011 to 13.06.2011 from the office of Superintending Engineer, Operation Circle,

HPSEB Ltd. Solan against the payment as shown against the work in shape of demand Draft

payable at Solan in favour of Sr. Executive Engineer, Electrical Division HPSEB Ltd. Solan.

Name of Work Estimated cost

Earnest Money

Complet-ion Period

Cost of Tender Document

Sale of Tender Document

Receipt of Bids

Opening of Bids

Name of work: - Supply of Power

to ESIC Hospital

Katha Under ESD

Barotiwala.

(S.H.) “Survey, Design,

Supply, Erection,

testing &

commissioning of

11 KV HT line

with AB cable 3

core 240mm S.q.

Rs.

2083965/-

Rs.

52100/-

2

Months

Rs.1000/-

+8% Sales

Tax =

1080/-

1.06.2011

to

13.06.201

1 (4.00

PM)

14.06.201

1 (11.00

AM)

14.06.2011

(3.00 PM)

Before issue of the tender documents, the bidder shall have to

furnish adequate documentary evidence in support of qualifying

requirements stipulated as below:-

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1. CATEGORY-I:- The bidder/ Joint Venture Firms having A-Class License from Chief Electrical Inspector of any state/ union territory of India other than Himachal Pradesh, but they will have to register with CEI to HP within 2 months of the award. The Bidder shall be financially sound and average annual turnover of the bidder for the past 2 years, out of last 5 years should be Rs.1.0 Crore. As a proof of turnover the bidder shall have to produce a certificate from the Bank/ Chartered Accountant. The Bidder should have designed, erected and commissioned 3.00 Kms 11 KV HT line with AB cable and it should be in successful operation for the last two years at the time of sale of bid documents.

2. CATEGORY-II:-The Bidder/ joint venture Firms having A-Class

License from Chief Electrical Inspector, H.P. and having registered office in H.P. The Bidder should be financially sound and average turnover of the bidder for the past 2 years, out of last five years should be Rs. 1.0 Crore. As a proof of turnover the bidder shall have to produce a certificate from the Bank/ Chartered Accountant. The Bidder should have designed, erected and commissioned at least 3.00 KM 11 KV HT Line with AB cable and it should be in successful operation for the last two years at the time of sale of bid documents.

3. CATEGORY-III:- Bidder/ Association of retired employees of HPSEBL

having A-Class License from Chief Electrical Inspector, H.P. The bidder should have been in technical services of HPSEB for at least 20 years and in this regard certificate from HPSEBL’s serving Engineer not below the rank of S.E. shall have to be produced along with the list of works operated. However, the bidder/ any member of the association should not have been retired within 2 (Two) years of active service of the Board from the date of bidding. The bidder shall supply an asset statement equivalent to 30% of the Estimated Cost, at the time of purchase of tender duly certified by the Scheduled Bank/ Co-Operative Bank or C.A.

4. The Bidder should have Income Tax/ Sales Tax (VAT)/ CST/ Service Tax/ Employees Provident Fund registrations as required under Rules.

5. The bidder will declare on Non Judicial Stamp Papers that he is not

Black Listed by any State or Central Govt. Agency/ Department. Contd. Page-3

Page-3

6. The Earnest Money shall be received in shape of demand draft payable at Solan in favour of Sr. Executive Engineer, Electrical

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Division, HPSEBL, Solan. The EMD available against other works will not be transferable to this tender.

7. The detailed terms and conditions can be seen in the tender

documents.

8. If the date of receiving/ opening of the tenders happen to be a holiday,

the tender will be received/ opened on the next working day. 9. The bid documents are not transferable and cost of bid documents is

not refundable under any circumstance.

10. Telegraphic tenders and tenders without Earnest Money will not be

accepted. 11. Undersigned reserves the right to reject any or all the tenders without

assigning any reason and no contractor shall be allowed to put up the tender after stipulated date and time.

12. Undersigned reserves the right to increase/ decrease the quantum of

work as per requirement at site.

Superintending Engineer,

(Op) Circle, HPSEBL Solan.

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OPERATION CIRCLE, HPSEBL, SOLAN-173211 (H.P)

PART-I Technical Bid (Vol-I)

Tel. No. 01792-221481 Tele. Fax: 01792- 223652

PROVIDING ADDITIONAL 11 KV FEEDER FROM 220/66/11 KV S/STN. KATHA

TO KAILASH VIIHAR UNDER ESD BADDI DISTRICT SOLAN (H.P.)

Sub-Head:- Erection of 11 KV HT line by laying 11 KV XLPE cable 3 core 300MM

Sq in cable trench.

Package-1:- Erection of 11 KV HT line by laying 11 KV XLPE cable 3 core 300mm Sq in

cable trench = 1.6 KM .

BID No. – HC-II-DB-TENDER-10- DATED 10.Feb.2010

Superintending Engineer,

(Op) Circle, HPSEBL, Solan.

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SECTION-I

CIRCLE:- (Operation Circle, HPSEBL Solan )

DIVISION:- ( Electrical Division, HPSEBL Baddi.)

1. Standard:- All the material and equipment shall comply in all respect with the latest standard

or any other equivalent standards. The standards to which equipments offered shall be

stated in the bid.

2. Safety Margin in Design:- The design, dimensions and material of all parts shall be such that they shall not

suffer damage under most adverse conditions.

3. Electricity Rules-III All design and works pertaining to the supplies and installation of the

specifications shall confirm to the various rules in force under Electricity Act, Rules and

other legislations / regulations applicable at the place of the site .

4. Technical Deviations:- The bidders shall make his offer in consonance with the specified requirements.

In case the bidder wishes to depart from specifications in certain respects without

affecting the basic functional requirements or stipulations he shall submit a complete and

item wise list of such deviation / departure together with full particulars of the reasons for

the departures, in a separate schedule with reference to sections and paragraph numbers

of the bid document. The deviations shall be considered valid only in case the purchaser

has accepted the same formally. In the absence of such acceptance the equipment offered

shall be deemed to comply in every respect with these specifications.

The bidder, however, is free to offer special devices or equipment with a view ti

increase the performance / efficiency and life of the plant and minimize the initial cost or

maintenance cost of the equipment as a whole.

5. EXTRA WORKS:-

In case it is felt necessary , the purchaser may modify the quantitative

requirements in respect of equipment and related works and services of the bid

specifications at any time prior to the placement of order or subsequently, and the

supplier shall be bound to accept the same. Quantitative modifications shall, however be,

to a limited extent only. The prices shall be subject to adjustment for any specific

quantative modifications thus made.

The supplier shall , when asked in writing by the purchaser , supply the extra

quantity, perform extra work / furnish extra material not covered by the specifications or

included in the schedule but otherwise forming an inseparateable part of the work

contracted for or whose supply is considered essential by the purchaser. Extra payments

for such equipment, work or materials shall be applicable which shall be mutually agreed

upon and sorted out in advance between the supplier and the purchaser.

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6. GAURANTEES.

The contractor shall guarantee among other things the followings.

(a) Quality and strength of material used.

(b) Adequate factor of safety for all parts of equipment to withstand the mechanical

and / or Electrical Stresses developed therein.

© Suitability of design and workmanship of the equipment for the conditions

prevailing in the area.

(d) Satisfactory erection and commissioning of the equipment at site.

(e) The efficiency, temperature rise and other performance data prevailing in the area

for equipment as applicable in accordance with relevant standards & provisions for these

specifications.

(f) The delivery periods given in the bid.

It must be clearly understood that the contractor shall be responsible for replacing

at site, free of cost, any parts of the equipment that may prove faulty or fail by reason of

any of the causes within EIGHTEEN months after equipment has been put into operation

FORTY EIGHT months after delivery of the complete unit, whichever is later.

In case of any defect in the equipment the supplier shall rectify the same by

permissible repairs or replacement of the defective part at his own cost and after

successful rectification of the defect, the guarantees shall be applicable a fresh for a

period of 18 months from the date of such rectification.

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TECHNICAL SPECIFICATIONS:-

Name of work: - PROVIDING ADDITIONAL 11 KV FEEDER FROM

220/66/11 KV S/STN. KATHA TO KAILSH VIIHAR UNDER ESD BADDI DISTRICT

SOLAN (H.P.).

Sub-Head:- Erection of 11 KV HT line by laying 11 KV XLPE cable 3 core 300MM Sq in

cable trench

Chapter-I

ISI Marked DWC (Double Wall Corrugated) HDPE pipes:-

For laying of Power Cable applications.

TECHNICAL SPECIFICATIONS:-

TYPE (i) The HDPE pipe shall be double wall corrugated of standard make suitable

for laying 3-core 300mm square XLPE cable underground.

STANDARD:-

(ii) The HDPE pipe shall be ISI marked and complying to technical

requirement of IS-14930.

Size:- (iii) The HDPE pipe shall have OD/ED (mm) as 180/152 and have standard

length of 6 meters.

Fitting and Assembly. (vi) The scope of work shall include all fittings and accessories namely End

Caps, Bends, Tees etc required for the successful execution of laying work of the HDPE

pipe.

Non-flame propagating properties. (v) The HDPE pipe shall be of non-flame propagating type as per IS-14930

(Part-II).

Antirodancy (vi) The HDPE pipe shall have antirodancy property to prevent damage caused

due to rodants.

Inspection & Test (vii) The HDPE pipes shall be offered for inspection at manufactured work

before dispatch and test as per relevant IS shall be conducted by the authority

representative of purchaser.

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Guaranteed technical parameters of HDPE PIPE

(i) Name of manufacturer

(ii) Size of HDPE pipe (O/D)(1/0)mm.

(iii) Standard length

(iv) Colour

(iv) Method of Jointing

(v) Material

(i) whether having non-flame propagating property.

(ii) Whether having Anto-rodancy feature.

(vii) Detail of fitting accessories.

(viii) Detail of past supplies & performance.

(ix) Type test certification.

CHAPTER -II

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TECHNICAL SPECIFICATION FOR 12KV, 630 Amp, (25KA for 3 Sec)

HORIZONTAL BREAK, CENTRE POST ROTATING ISOLATORS

INDEX

Clause

No.

Title Page

No.

1.01 Scope 2

1.02 Particular of System 2

1.03 Standard 2-3

1.04 Requirement of Material 3

1.05 Horizontal Break Center Post Rotating

Isolators

3

1.06 12 KV Isolators 4

1.07 Earthing switches 4

1.08 Service Conditions 4

1.09 Technical particulars 5

1.10 Isolator insulation 6-7

1.11 Structure Foundations 8

1.12 Auxiliary Switches 9

1.13 Mechanical Strength 9

1.14 Interlocking 9

1.15 Design Feature 10-12

1.16 Fasteners 12

1.17 Metal Parts 12

1.18 Control Connection and Wiring 12

1.19 Name Plates 12

1.20 Isolator Base 12

1.21 Spare Parts 13

1.22 Special Tools 13

1.23 Cable Boxes 13

1.24 Completeness of Equipment 13

1.25 Material and Workmanship 13

1.26 Drawing and Literature 13

1.27 Tests 14-15

Annexure-I GTPs 16-19

TECHNICAL SPECIFICATION FOR 12KV ISOLATORS

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1.01 SCOPE

This specification covers the design manufacture, assembly, testing before

dispatch at manufacturer’s works, supply and delivery to station of 12KV out

door type manual operated isolators with and without earth switches along

with associated structures complete with accessories and auxiliary equipment

for installation in 33/11 KV sub station in Himachal Pradesh at Arki for 11KV

outgoing feeders. Any equipment not specifically mentioned but required for

satisfactory operation of the isolating and earthing switches in the opinion of the

tenderers must be included in the offer.

1.02 PARTICULAR OF SYSTEM

The line isolating and earth switches shall be suitable for a three phase solidly

grounded system with 50 cycles per second frequency, for the voltage class for

which these are meant.

1.03 STANDARDS

The isolating and earth switches shall comply with the requirements of the latest

editions of the following Indian standards.

(1) Alternating current Disconnectors (Isolators) and Earthing switches for

voltages above 1,000 Volts.

a. Part I General & definitions: 9921(part 1) 1981

b. Part 2 Rating: 9921 (part 2) 1982

c. Part 3 Design and construction: 9921 (part 3) 1982

d. Part 4 Type test & routine tests: 9921 (part 4) 1985

e. Part 5 information to be given: 9921 (part 5) 1985

With tender, enquiries and orders.

(2) Making and arrangement for IS 375-1963

Switchgear bus bars main connections

and auxiliary.

(3) Dimensions of indoor and outdoors 5350(PART-II) 1973

Porcelain post insulators and post

Insulator units for systems with nominal

Voltages greater then 1000 V.

(a) Out door cylindrical post insulators: 5350(Part-II) 1973

(b) Outdoor pedestal post insulators : 5350(Part-III) 1971

(4) a. 245 KV bushing porcelain parts : 3347(Part7/Sec-1)1977

b. 245 KV bushing metal parts : 3347(Part7/Sec-2) 1982

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c. 145 KV Bushing porcelain parts : 3347(Part7/Sec-1) 1977

d. 145 KV Bushing metal parts : 3347(Part7/Sec-2) 1982

(5) Porcelain post insulators for system : 2544-1973

with nominal voltage greater than 1000

Voltage (First revision).

(6) Specification for structural steel : IS 266-1975

(Standard quality) Vth revision.

(7) Recommended practice for hot dip : IS-2629

Galvanizing of iron and steel.

(8) Method for testing uniformity of : IS-2633

Coating of zinc coated articles.

(9) Specification for hot dip zinc coating : IS-4759-1979 on

Structural steel and

other Allied

products.

(10) Specification for zinc : IS-209-1979

(11) Hexagon bolts for steel structures : 6639-1972

(12) Heavy washers for steel structures : 6610-1972

(13) Galvanization of bolts and nuts : IS-5358-1969

(14) ISI handbook for structural : SP 6(I)-1964

Engineers

(15) PVC cables : IS-1554

(16) Power connectors : IS-5561

(17) Motors (If required) : IS-325

1.04 Equipment and material meeting the requirements of IEC or any other

internationally recognized standard which ensure quality equal or better than the

standard: mentioned above, shall also be acceptable. Where the equipment

conforms to any other standard, the salient points of difference between the

standard adopted and those prescribed in this specification shall be clearly

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brought out in the tender and a copy of the applicable standards shall also be

enclosed by the tenderer with the tender.

1.05 HORIZONTAL BREAK CENTRE POST ROTATING DOUBLE BREAK

ISOLATORS In this type of construction, there shall be three insulator stacks per pole. The two

on each side shall be fixed and one at the center “rotating center post”. The

Central insulator stack should swing about its vertical axis through about 900. The

isolating switches shall be double break rotating center post type for 12 KV

systems. The central post shall carry the moving tubular or flat contact arm with

the contacts, assembled at the extremities. The moving Contact shall engage the

fixed contact on the fixed contact on the fix insulator post. Mechanical

interlocking of the three poles shall ensure the simultaneous operation of three

poles. The design of moving and fixed contacts shall be sturdy so to carry the

continuous rated current without over heating and damage.

The contacts should engage perfectly so that there is no speaking while in service.

One of the contacts shall be male contact while the other is female contact. The

female contact shall be spring loaded finger contact type. The moving and fixed

contacts shall be made out of the silver faced copper in such a way that the

maximum temperature rise above 500C ambient should not be more then 65

0 C

while designing the equipment care should be taken that this temperature rise does

not cause damage to surrounding insulating material. The terminal of isolator

shall be silver plated for connection to external conductor by bolted connection.

The rotation of the central post shall be affected through a drive liver at the base

of each post connected by the operating and driven from one post by the operating

mechanism through an adjustable lever

1.06 12 KV ISOLATORS

12KV isolating switches shall be suitable for local manual operation. It shall be

possible to pad lock the manual operating handle both in open and closed position

of the switches. Isolator blades shall be so interlocked with the main breaker that

these can only be closed, if the circuit breaker is in open position. Similarly, it

should be only possible to open the isolator when the circuit breaker is in open

position. The earthing connection for the operating handle is included in the scope

of supply which shall comprise of copper leads between the operation handle and

station ground mat and interconnection between the phase bases. Six pairs of N.C.

and N.O. auxiliary switches as per detail are given here in after shall be provided

in the mechanism box for sinter locks and indications in the control room.

1.07 EARTHING SWITCHES: -

The earthing switches shall be manually operated mounted on the isolating switch

base on the line side: The earth switch shall comprise of vertical break type arm

with the contact extremity, which engages with the isolator contact on line side.

The earthing isolator and line isolator shall have a separate operating mechanism

as well as auxiliary switches to indicate in the control room, open or close

position. It should be possible to pad lock the manually operating handle of the

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switch both in open and close position. The earthing connection for correcting the

earth switch shall also be in scope of supply of supplier. This short circuit current

the earthing switches shall be of the same current carrying capacity as the main

blades.

1.08 SERVICE CONDITIONS

1. Maximum Ambient air temperature = 500C

2. Minimum Ambient air temperature = -50C

3. Altitude where these isolators have to be =below 2000 meters.

Installed

4. Relative Humidity =100%

5. Any other special conditions. =A. Excessive dust is

prevalent in Air

6. Earthquake Forces :

The equipment should be designed to withstand the

earthquake forces giving dynamic acceleration of 0.5g in

all the directions at a frequency of the order of 10 cycles

per second. Detailed calculations made for design of the

various equipment taking into account above Seismic

forces shall be furnished to the Bidder.

1.09 TECHNICAL PARICULARS/RATINGS 12KV Isolators

1. Number of poles Three

2. Class (Outdoor Air break

type)

3. Nominal system voltage 11KV

4. Highest system voltage 12KV

5. Rated frequency 50 Hz

6. Phase to phase spacing for installation 1300mm

7. Minimum clearance

(i) Phase to earth 430 mm

(ii) Phase to phase 1300 mm

8. Height of centerline of terminal 4300 mm

Pad above ground level.

9. Rated Insulation without arching hours

(i) To earth & between poles. 170 KV

(ii) Across the Isolating distances 195 KV

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10. One minute power frequency withstand test voltage (rms).

(i) Earth & between poles. 75KV

(ii) Across the Isolating distances 85 KV

11. Continuous rated current 630 Amps.

12. Short time withstand current rating from main 25 KA

Switch & earth switch for three second.

13. Rated peak withstand current 63 KA

14. Rated mechanical terminal load As per table 7 of IS: 9921

(Part-II) 1982 or as per value

to be calculated vide clause

1.16.2 whichever is higher.

15. Rated short circuit making current 25 KA

for earthing switch.

16. Neutral grounding Solidly grounded system.

17. Method of Operation Manually Operated

18. Number & type of auxiliary switches. Six pairs of NO & NC

Auxiliary switches of 10 Amps

30 VDC.

19. Control supply for semaphore lamp indications. 30VDC

SOLID CORE POST INSULATORS

20. Creep-age distance. 320 mm

21. Terminal connector bimetallic

22. terminal Connectors

(WITH NON-MAGNETIC

STAIN LESS STEEL NUTS

BOLTS WASHERS) suitable

for ACSR Panther or the size

will be intimated at the time

of drawing approval.

1.10 ISOLATOR INSULATION

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Insulation to ground, insulation between open contacts and the insulation between

phase of the completely assembled isolator shall be capable of withstanding the test

voltages as specified in clause 1.09 above. Insulation between open contacts of a pole

shall be (as per IS: 9921 part-II-1982) more than the insulation between the live parts

of a pole to ground so that if any flashover when switch is open, it shall be to the

ground.

Post insulators used in the isolators shall be SOLID CORE porcelain type suitable for

operation on system rated voltage and system earthing conditions given in the

specification. The porcelain used for manufacturer shall be sound, free from defects,

thoroughly vitrified and smoothly glazed. The glaze shall be brown in colour. The

glaze shall cover all the exposed porcelain of the insulator except those areas, which

serve as support during firing. Precaution shall be taken during design and

manufacture to avoid stress concentration due to direct engagement of porcelain with

the metal fittings, retention of water in the recesses of metal fittings. Shapes, which

do not facilitate easy cleaning by normal method, should be avoided. Cement used in

the construction of post insulator shall not cause fracture by expansion or loosening

by contraction. The cement shall not give rise to chemical reaction with metal fittings

and its thickness shall be as uniform as possible. All ferrous metal parts except those

of stainless steel if used shall be dip galvanized and the uniformity of zinc coating

shall satisfy the requirement of IS-2633-1964. The finished galvanized surface shall

be smooth.

The threads of tapped holes in the post insulator metal fitting shall be cut after giving

anticorrosion protection and shall be protected against rust by greasing. The tapped

holes shall be suitable for bolts with threads having anticorrosion protection. The

effective length of threads shall not be less than nominal diameter of bolts.

The post insulators shall be assembled in a suitable jig to ensure correct positioning of

top and bottom metal fittings relative to one another. The faces of metal fittings shall

be parallel and right angle to the axis of insulators and corresponding holes in top and

bottom metal fittings shall be in a vertical plane containing the axis of insulator.

Post insulator shall be legibly and indelibly marked to show the following:

a. Name and trade mark of manufacturer.

b. Month and year of manufacture.

c. ISI certification mark.

Marking on porcelain shall be printed before firing. These insulators shall conform to

relevant ISI/IEC. The insulators shall have requisite insulation, mechanical strength,

and thermal capability for satisfactory operation under site conditions. The creepage

distance shall not be less than 25 mm/KV.

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The insulator shall be suitable for use in moist and polluted atmosphere. The

insulators shall be capable to withstand bending and tensile strength as per relevant

ISS/IEC. Insulator shall not fail when subjected to torsion strength in tensional load

of 2.5KN and bending strength of 4KN in case of 36KV insulator. The insulator shall

be capable of withstanding the electrodynamics as well as thermal stresses.

1.10.1 SOLID CORE INDULATORS 12KV

1. Make IEC/ Modem

2. Application standard IS 2544

3. Type Solid core

4. Minimum creepage distance 320 mm

5. All ferrous parts to be hot dip galvanized

ELECTRICAL VALUES

1. Nominal system voltage 11KV

2. Highest system voltage 12 KV

3. 1 minutes P.F. withstand voltage

(Dry) 28KV (rms)

(Wet) 28KV (rms)

4. Impulse withstand voltage 70 KVP

5. Visible discharge voltage 9KV (rms)

ISOLATOR INSULATION:

Insulation to ground, insulation between open contacts and the insulation between

phase of the completely assembled isolator shall be capable of withstanding the test

voltage as specified in Clause 1.09 above. Insulation between open contacts of a pole

shall be (as per IS-9921 Part-II 1982) more than the insulation between the live parts

of a pole to ground, so that if any flashover occurs when switch is open, it shall be to

the ground.

1.10.2 INSULATOR

The insulator shall be solid core type; Porcelain PEDSTAL INSULATORS shall

not be acceptable. The makes of JSI/Modem/IEC/W.S. will be preferred.

1.10.3 MOUNTING OF ISOLATORS

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The isolators shall be mounted on the top of separated galvanized steel structure. All

couplings etc. of the main operating rods shall also be included in the scope of

supply. The height of the operating box above the ground shall be approximately

1500mm.

The operating box shall be mounted on the side of structure and it shall be at a height

of 1500mm above the ground level. Necessary length of operating rod, couplings etc.

shall be included in the scope of supply along with the earthing leads.

Where the isolators are mounted on the top of separate galvanized steel structure, the

structures shall form part of the supply scope of this specification. The structure shall

be fabricated from structural steel conforming to IS-226-1975 and shall be hot dip

galvanized as per IS-4759-1979. The purity of the zinc shall be as per IS-209-1979.

The galvanized nuts and bolts including 2.5% spares conforming to IS-6639-1972

along with galvanized washer shall be supplied along with the structure. The

galvanization of the nuts and bolts shall conform to IS-5358-1969.

The support structure shall be suitable for mounting operating mechanism etc. It shall

be designed to withstand short circuit force, wind pressure, seismic force etc. along

with the operating force vibration, shocks etc. at actual site conditions with adequate

factor of safety. The tenderer shall furnish detailed design calculation etc. for

supporting structures. These details shall also include loading data. The isolators to be

mounted on gently shall be supplied with sufficient length of operating pipe and

other, accessories to suit site requirements. In order to enable design of beam for their

mounting, necessary details of weight, dimension etc. shall be furnished to the Bidder

sufficiently in advance.

1.11 STRUCTURE FOUNDATIONS

(In case the isolator is to be erected on self-supporting G.I. structure)

The successful tenderer will be required to furnish detailed design calculations for the

structure foundations along with the dimensional drawings showing details of

reinforcement etc. The soil in which the foundations have to be laid is generally

cohesive with a safe bearing capacity of 16 Ton/m² with angle of friction as 300.

Basic design data for the structure and foundation is as below.

1. Wind pressure on Steel structures on = 195kg/m²

1.5 Times the exposed area of one face.

2. Wind pressure on conductor & ground wire = 122kg/m²

on full projected area.

3. Weight of dry earth = 1440kg/m³

4. Weight of reinforced cement concrete = 2400kg/m³

5. Concrete mixture to be used for

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(a) Pyramid or stepped part of foundation = M-15

(b) Pad = M-15

(c) Factor of safety for structure As well as foundation = 2

The passive pressure of earth shall not be considered for resisting the side thrust. In

addition, the tenderers shall specify and take into consideration the load, which shall

be transmitted to the equipment foundation under most adverse operating conditions

of the isolators.

The masonry or concrete in foundations shall be arranged and constructed by the

bidder and all requirement of foundation bolts for the structures shall be in the scope

of bidder.

1.12 AUXILIARY SWITCHES

Auxiliary switch shall be provided with each isolator and earthing switch for remote

indication and interlocking Six pairs of sturdy silver-plated NO and NC contacts shall

be provided with each auxiliary switch. Each stage of the auxiliary switch should

consist of one moving contact and two fix contacts backed by phosphors bronze leaf

springs. Connections from the auxiliary switches shall be brought to a terminal block

with the help of 2.5mm standard copper cable. The ends of this cable shall be crimped

with cable lug for connection purposes. A suitable terminal box shall be provided

beneath auxiliary switch housing for multicore control cables. For the insertion of

multicore cable in the housing cable glands of 25mm dia with a suitable rubber bush

shall be provided. The auxiliary switch shall strictly conform to the provisions of IS-

9921 or its equivalent IEC. Signaling of close position of isolator shall not take place

unless movable contact reaches their fully open position. The capacity of each contact

of these switches shall not be less than 10Amps continuous and permissible

temperature rise of the auxiliary switch contact shall be in accordance with Table-4 of

IS: 9921 Part-II. The auxiliary switches shall be capable of breaking at least 2 Amps

at 30 volts. D.C. with a time constant of not less than 20 milli seconds. Auxiliary

switches shall be positively driven in both directions. Provisions shall be kept for

adding more auxiliary switch contacts at a later stage. Separate auxiliary switches

shall be provided for isolating and earth switches. It should be possible to change

normally closed contact into a normal open contact and vice versa at site. Quick make

and break type auxiliary switches shall have been snap action built within the switch.

A cam shall actuate the auxiliary switches or similar arrangement directly mounted on

the isolator shaft without any intermediate levers linkages etc to ensure foolproof

operation.

1.13 MECHANICAL STRENGTH OF ISOLATOR

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Mechanically the isolator must be robust and able to operate successfully under

extreme climatic conditions, high winds, earthquake, low temperature and severe

pollution.

1.14 INTERLOCKING

To prevent the incorrect operation of isolating switches, earthing switches and

breakers, mechanical as well as electrical interlock shall be provided i.e. isolating

switches shall be blocked against the respective circuit breakers, switches. The

mechanical interlocking shall be provided in between isolating switch and its

earthing switch. Electrical interlock with solenoid coil in addition to mechanical

interlock shall be suitable for 30V DC supply available at site Requirement of

interlock shall be as given below:

1. Isolator should not be operated unless the associated breaker is in open

position.

2. Earthing switch shall close only when the line isolator is fully open and

locked.

3. Line isolator shall close only when the corresponding circuit breaker and

earthing switch of the corresponding lines are open.

4. The circuit breaker shall close only after all isolators associated with it

have been locked either in close or open position.

5 The bypass isolator of feeder shall close when the feeder circuit breaker

and its adjoining isolators are closed.

6 The bypass isolator of feeder shall close manually irrespective of fact

whether the feeder circuit breaker and its adjoining isolator are open and

closed.

1.15 DESIGN FEATURE

1.15.1 CONTACT SYSTEM

Contact shall be made out of hand drawn electrolytic grade copper. Arcing

contacts wherever provided shall close first and open last. The contact surface

shall be made with suitable jig to avoid deviations during up to 20-25 microns and

shall be made suitable jig to avoid deviations during production. The male and

female contact assemblies shall be of suitable design and their assemblies shall

ensure:

1. Electrodynamics with stand ability during short circuit without any risk of

repulsion of contacts.

2. Thermal withstand ability during short circuits.

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3. Constant contact pressure even when the live part of the insulator stacks

are subject to tensile stresses due to linear expansion of connected bus bar

or flexible conductors either because of temperature variation or strong

winds.

4. Self- wiping action during closing and opening

5. Self-alignment assuring closing of the switch without calling for minute

adjustments.

1.15.2 TERMINAL CONNECTORS

1. Each isolator connected with incoming and outgoing feeders shall be

provided with appropriate number of solder less clamp type bimetallic

connectors suitable for AAAC-7.4.26mm conductor for 12KV isolators.

Each isolator shall be provided with appropriate solder less clamp type

bimetallic connectors suitable for AAAC conductor as specified for 12KV

isolators. Each terminal clamp shall be suitable for both vertical and

horizontal connection of transmission line conductor or station bus bar

with non-magnetic stainless steel nuts & bolts. Each isolator shall also be

provided with appropriate number of ground terminal and clamps for

receiving ground connection. The earthing terminal shall a minimum dia

of 10mm.

2. 12KV isolator shall be able to withstand forces due to wind load on the

equipment and approach conductor and due to short circuit, all forces

considered together, for both type of isolators are connected to required to

required AAAC conductor with the adjacent span of 6 meters for 12 KV

isolators and with fault level of 25 KA isolators (12KV) for 3 seconds.

The bidder will have to submit detailed calculations providing the

satisfactory performance of the isolators in the above-mentioned

conditions.

1.15.3 MOUNTING OF CONTACTS

Fixed contacts shall be mounted on a block or channel welded 8 to 10mm thick

M.S. plate with holes for fixing on insulators. Slots shall be provided for marginal

adjustment of height of contacts. The contacts shall rest on a brass block and with

initial tension. Suitable device shall be provided to prevent dashing, fabrication,

welding etc. shall be done in suitable jig to avoid deviations during production.

1.15.4 TURN AND TWIST MECHANISM

Turn and twist mechanism shall be provided with adequate locking to avoid

opening or loosening by wind short circuit force etc. on moving blade. The

springs shall be made out of stainless steel or phosphor bronze or any other better

material to have adequate strength and resilience and shall be encased with grease

to avoid exposure to rain. The clamps and plates shall be made out of at least

10mm think. M.S. plate or flat. Fasteners with nylon lock nuts shall be used

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wherever necessary. Vulnerable parts shall be fabricated in suitable jig and

template to avoid deviations during production. Fasteners with nylon lock nuts

shall be used wherever necessary. Vulnerable parts shall be fabricated by tubular

gas cutting or milling. The entire mechanism shall be fabricated in suitable jig and

template to avoid deviations during production.

1.15.5 BEARINGS

Rotating insulator shall be mounted on a housing with bearings. The housing shall

be made of gravity die cast metal with smooth surfaces and suitably machined for

seating the bearing. Two number of bearing with adequate shaft diameter and

distance between the bearings shall be of minimum 75mm internal diameter and

of reputed make and lubricated of life. All other function locations shall be

provided with suitable bearings or stainless or brass bushes. The bearing bushes,

joints, springs etc. shall be so designed that no lubrication shall be required during

the service. Complete details of bearings bushes, housing greasing etc. shall be

furnished with the tender.

1.15.6 BALANCING OF HEIGHT:

Fixed insulators shall be provided with elevator base plate with four studs for

balancing of heights for isolator of rated Voltage of 12KV thickness of plate and

diameter of stud shall be at least 10mm and 25mm respectively. Adequate

numbers of nuts, lock nuts and washers shall be provided. Taper washer shall be

provided to match inclined surface of steel sections.

1.15.7 TANDOM PIPE:

Tandem pipes shall be used for phase coupling of double break isolators. Base

plate of insulators for connection of tandem pipe shall be made out of one piece of

at least 10mm thick M.S. plate. Bolt and shackle device shall be used to connect

tandem pipe to the base plate. These clamps shall be made out of at least 10mm

thick M.S. flat with four nos. of nuts and bolts. A grub screw shall be provided for

securing connections on tandem pipes. The tandem pipes shall be suitable to

connect the isolator in any position.

1.15.8 DOWN PIPE

At least 50mm Internal Dia and class B pipe shall be provided for operating

isolators. The pipe shall be terminated in to a suitable swivel or universal type

joint between the insulator bottom bearing and the operating mechanism to take

care of marginal angular misalignment of site. All brackets, guides etc. shall be

mounted on the base of the isolator. Arrangement of mounting any guide, bracket,

parts etc. on support structure accept the operating mechanism and the base shall

not be accepted.

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1.15.9 BASE

Each phase of isolator shall be provided with a rigid base fabricated from steel

sections. The base shall be suitable for mounting on support structures.

Fabrication, welding etc. shall be done by suitable jig, power press, and templates

to avoid deviations during production. Details and dimensions of section, jig

templates and device used for production of the base shall be furnished with

tender.

1.16 FASTNERS

Nuts, bolts and washers of 16mm and higher size shall be hot dip galvanized. The

bolts used on tapped holes of insulator cap shall be galvanized by centrifugal

process to avoid excess deposition of zinc on threads, Nuts, bolts and washer of

less than 10mm size shall be of stainless steel when used on live parts and nickel

plated brass in other parts.

1.17 METAL PARTS

All ferrous parts shall be hot dip galvanized. Bolts, nuts, pipe and washers etc.

Used on the isolators shall also be galvanized. All current carrying parts shall be

of non-ferrous metals or alloys and designed to limit sharp points, edges and

similar sharp faces. All other element shall be made of non-corrodible elements.

Isolating and earth switches may be subjected to serve atmospheric and service

conditions, therefore proper protection against corrosion shall be ensured. Design

of isolator contact shall permit easy maintenance and renewal of contacts.

1.18 CONTROL CONNECTION AND WIRING

All cable and wiring shall be suitable for outdoor operating conditions. Operating

box connections shall be insulated and fixed neatly and securely. The wiring shall

be self-extinguishing type taken from/to suitable terminal boards and run in

porcelain or non-rusting metal cleats of the limited compression type. All box

wiring shall be 2.5mm2 standard copper of 1.1KV grade.

1.19 NAME PLATES

The Isolators shall be provided with a nameplate, the nameplate shall be weather

proof and corrosion proof. It shall be mounted in such, position that it shall be

visible in the position of normal and installation. It shall carry the following

information duly punched or engraved on it.

1.20.1 ISOLATOR BASE

Name of the Manufacturer :

Year of manufacturer :

P/O No. :

Type & Designation :

Serial No. :

Rated Voltage Frequency

Rated Normal Current

Rated Short Time Current MS ES

Rated Short Time Peak Current MS ES

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1.20.2 OPERATING MECHANISM

Name of the Manufacturer

P/O No. Year

Type & Designation

Reductive gear ratio

Auxiliary contacts quantity & rating

Terminal blocks quantity & rating

Number of revolution for one close or open position

1.21 SPARE PARTS

The prices of the mandatory spare parts as listed in Annexure shall be indicated

separately in the price bid and the same shall be considered for the purpose of

tender evaluation. However the actual quantities of spare parts to be procured

shall be decided by the Bidder.

The tender may also recommend optional spare parts in addition to the mandatory

spares considered necessary for five (5) years of successful operation of the

equipment. The prices of these optional spare parts shall be as per Annexure -

However, these shall not be considered for bid evaluation. The prices of optional

spare parts shall be firm and the Bidder reserves the right to procure them any

time during the execution of contract. Spare parts catalogue depicting part

member shall be supplied.

1.22 SPECIAL TOOLS

The tenderer shall separately quote for a set of tools required for initial erection

and subsequent maintenance of the isolator and its operating mechanism. Item

wise unit prices for each tool shall be quoted in the tender. The prices of tools

shall however, not be considered for bid evaluations.

1.23 CABLE BOXES

Cable boxes including cable glands for terminating multi-core control and power

cables shall be provided wherever required. The supply shall include necessary

connecting material for mounting of cable boxes in accessible position clear of the

floor level to make the jointing work easy.

1.24 COMPLETENESS OF EQUIPMENT

All fittings, accessories or apparatus which may not have been specifically

mentioned in these specifications but are necessary for the satisfactory working of

isolator and earth switches shall be complete in all details, whether such details

are mentioned in these specification or not.

1.25 MATERIAL AND WORKMANSHIP

All material used in the construction of the equipment shall be of the best quality

available in respective kind and whole of the work should be of approved design

and make.

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1.26 DRAWINGS AND LITERATURE

In addition to any other drawing, which the tenderer may enclose to show the

merits of his equipment, the following shall be enclosed with the tender:

1. Drawing showing the outline dimensions of isolating and earth switch.

2. Sectional view and description details of items such as moving blades,

contact arms, contact spring, contact support, turn and twist mechanism,

bearing, housing of bearing, bushes, balancing of heights, phases, coupling

pipes, base plate, operating shaft, guides, swivel joint mechanism, and its

components etc.

3. Mechanical interlock between earth and isolating switches.

4. Electrical connections of controls.

5. Equipment for electrical interlocking.

6. Structure drawing for mounting of isolators along with bill of material.

7. Foundation drawings.

8. Fixing details of structures & isolators.

9. Solid core post insulator drawing with end flanges.

1.27 TESTS

Each isolator and earth switch shall comply with the following tests.

1.27.1 TYPE TESTS

1.27.1.1 The equipment/material offered in the Tender should have been

successfully type tested in line with standard and Technical Specification from

Independent test house. The bidder shall be required to submit three copies of the

type test report along with the offer. Tenders not accompanied with all type test

reports shall not be considered.

Detail of Type Test

1) Dielectric tests. (Power frequency & lightening impulse).

2) Temperature rise test.

3) Short time with stand current and peak with stand current test on main

switch.

4) Type tests on solid core insulator (as per ISI-2544).

5) Type tests on Terminal connectors.

6) Operating and mechanical endurance tests. On isolators, operating

mech. and auxiliary switches

1.27.1.2 If there is any change in the components or designs in the equipment since after

passing of the Type-test, the bidder shall bring out in his offer all such changes

made in the components, materials, designs etc. In such case the bidder shall

carryout the type test at his cost and in the present of Bidder’s representative.

1.27.1.3 Even if the equipment/material has been type tested earlier, the Bidder reserves

the right to demand repetition on one or more test included in the list of type

tests in presence of Bidder’s representative. For this purpose the bidder shall

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quote unit rates for carrying out each type test included in the list of type tests as

per relevant Standard and Tender Specification.

1.27.1.4 During the type test the disconnector shall be mounted on its own support

structure or equipment support structure if any and mounting arrangements

made for type test shall be furnished for Bidder’s approval before conducting

the type tests.

1.27.1.5 The type tests shall be connected on the Disconnectors along with approved

insulators and terminal connectors.

1.27.1.6 Mechanical endurance test shall be conducted on the main switch as well as

earth switch on one Disconnectors of each type.

1.27.2 ACCEPTANCE AND ROUTINE TAESTS

Routine tests as per IS 9921 (Part-4) IEC 129-1961 shall be carried out on each

isolator in the presence of Bidder representative expenses for the routine test

conductance shall be borne by the manufacturer. All test reports should be

submitted and got approved from the Bidder before the dispatch of equipment.

The tenderer shall however submit the details of routine tests facilities, which

are available in their works.

1.27.2.2 Mechanical operation tests (routine tests) shall be conducted on the complete

isolator (main switch and earth switch) at supplier’s works and a certified test

report be furnished to the Bidder.

1.27.2.3 The test report of power frequency voltage withstand test conducted on the

insulators shall be furnished for Bidder’s acceptance in lieu of conducting

power frequency test on main circuit (routine test).

1.27.3 SPECIAL TESTS

Special tests as listed below shall be carried out in the presence of Bidder’s

representative. Without any price implication.

1. Tests on insulators IS 2544/IEC168

2. Tests on terminal connector IS:5561 or Equipment

standard

3. Tests on galvanized component IS: 2623

4. Operation tests on operating Mechanism and interlock.

5. Endurance test on auxiliary Switches.

6. Tests on silver coating.

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1.27.4 Test certificates and documents of the following items shall be furnished at the

time of routine tests.

a. Chemical analysis of copper along with a copy of central excise

certificate/gate pass indicating genuine source of procurement of

electrolytic grade copper.

b. Bearings.

c. Fasteners.

d. Universal/swivel joint coupling

e. Insulators.

f. Gears.

g. Auxiliary Switches.

h. Interlocking Devices.

i. Terminal Block.

The Purchaser may at his discretion request additional test certificate for other

items as reasonably require to substantiating quality of the same.

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ANNEXURE-I

SCHEDULE OF GUARANTEED AND TECHNICAL PARTICULARS

(TO BE FILLED IN BY THE TENDERER)

SR.NO. DISCRIPTION 12KV ISOLATORS

1. Make of origin

2. Type

3. Mode of operation

4. Indoor or outdoor

5. Rated frequency

6. No. of poles

7. Rated Voltage.

8. Maximum permissible Voltage.

9. Power Frequency test Voltage (withstand)

(a) Against ground

1. Dry

2. Wet

(b) Across the open ends.

1. Dry

2. Wet

(c) Between phases

1. Dry

2. Wet

10. Impulses withstand test voltage without arcing horns for 1.2/50 micro sec.

impulse waves.

(a) Against ground.

(b) Across the open ends of the same phase.

(c) Between phase

11. No. Of break per phase

12. (i) Continuous current rating

(ii) Rated current at:

a. Reference ambient temperature.

b. Ambient temperature of 450C

13. Rated short time withstand current for 3sec.

14. Rated peak short circuit current

(a) Rated peak short circuit current of main disconnect or.

(b) Rated peak short circuit current of earthing blade.

15. Fault current, which can be made by the earthing switch.

16. Transformer magnetizing current that can be broken.

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17. Line magnetizing current that can be broken.

18. Type of terminal for receiving line/bus conductor.

19. Phase to phase distance

20. Auxiliary switches.

a. No. of normally open and normally.

b. Rated voltage.

c. Rated current.

d. Test voltage.

e. Terminal block type, voltage and current rating.

f. Details of electrical inter locking device.

g. Wattage of interlocking solenoid coil.

21. Design and construction

I No. of insulators per pole.

ii No. of breaks per pole.

iii Type of closing/opening mechanism

(turn and twist or straight etc.)

iv Female contacts.

22. Particulars of main contacts i.e. fixed contacts (main switch) and earthing switch

and moving contacts.

i. Type.

ii Material

iii Surface treatment.

iv Thickness of surface coating.

v. Contact area.

vi. Contact pressure.

vii Diameter of copper pipe moving blade(inner dia outer dia)

23. Arcing contacts:

i. Type

ii Material

iii Whether contacts silver plated

iv Thickness of plating

v. Current carrying capacity.

24. Current density at the minimum cross section in (A/Sq. mm)

i. Moving blade (Amps.Sq. mm)

ii. Terminal pad (Amps.Sq. mm)

iii. Female cont act (Amps.Sq. mm)

iv. Terminal connector (Amps..Sq. mm)

29

25. Rated mechanical terminal load.

i. Load along the terminal connector side.

ii. Load across the terminal connector side

26. Torque required to operate the switch (kg.m)

27. Contact support.

i. Material and size of channel/block.

iii. Material and size of plate.

28. De-rating factor for specified site conditions.

29. Minimum clearance in air:

i. Between poles (mm).

ii. Between live parts and earth (mm).

iii. Between live parts when switch is open

a. On the semaphore

b. Between adjacent poles (mm)

30. Insulators:

31. Make

a. Type

b. No. of units per isolator(mm)

c. Height of each insulator stack (mm)

d. No. of holes size and pitch circle diameter(mm)

e. Tensile strength.(kg)

f. Compressive strength (kg)

g. Tensional strength(kg-cm)

h. Cantilever strength upright (kg rms)

i. Rated voltage (KV rms)

j. Power frequency dry flash over voltage. (KV rms)

k. Power frequency wet flash over voltage. (KV rms)

l. Impulse withstand voltage (KV peak).

m. Impulse withstand voltage (KV peak)

n. Power frequency puncture voltage (KV rms).

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o. Visual discharges voltage level (KV rms)

p. Creepage distance total protected (mm).

q. Dry arcing distance.(mm)

32. Clearance (Minimum)

a. Between live parts and ground.

c. Between phase.

33. No. of times the switch can be operated without any need for inspection.

34. No. of operations which the switch can withstand distortion on contacts.

35. Weight of one three pole-isolating switch without earthing blade.

36. Weight of one three pole-isolating switch with earthing blade.

37. Base

a. Size of steel section used.

b. Overall size.-*

d. Total weight.

38. Terminal connectors.

a. Clamp body alloy composition plating if any. Area at minimum cross

section.

b. Bolts and nuts size alloy composition Tensile strength.

c. Type of washers used.

d. Material of braids.

e. Temperature rise when carrying rated current at 50 C ambient

f. Weight of each type of clamp (kg)

39. Tandems pipe.

a. Size class and No. of Pipes.

b. Size of shackle and screw.

c. No. of clamps and the material and size.

31

40. Down pipe size and class

41. Nuts and bolts.

a. Size material and grade in live parts.

b. Size, material and grade in other parts.

42. Turn and twist mechanism.

a. Material and size clamps.

b. Material and size of springs.

c. Whether springs are encased.

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32

Chapter-III

Excavation in Trenches

(i) The cable trench shall be of 1 mtr. X 0.6 mtr. Size. The bidder should quote his

rates for all kinds of soil including all leads and lifts.

(ii) The valuables if any extracted during excavation shall be returned to the

department by the contractor.

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