Distribution 50 HZ, - Manipur · 2014-02-25 · Distribution Transformer 100KVA, 1110.433 KV, 3 phm (three star ratings of BEE) Aluminium wound, complete with accessories, fittings

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OFFICE OF THE MANAGING DIRECTORMANIPUR STATE POWER DISTRIBUTION COMPANY LIMITED

KEISAMPAT, IMPHAL

NOTICE INVITING TENDER

lmphal, dated the 2{"t Feb 2Q14

No. 2/lipURCH :DT12O14-ED(MSPDCL)/: Sealed Tenders in triplicate are invited by the

Managing Director, Manipur State Power Distribution Company Limited(MS,PD_CL) a Government

of lrltaiipur enterprise from the reputed Manufacturers of the following Distribution Transformers.

Purchase of Tender Paper

Tender Papers containing detailed specification of the equipment to be procured with

detailed terms and conditions of the tender can be obtained from the office of the General

Manage(ppp), MSPDCL, lmphal -795001, Manipur on payment of the_cost of Tender paper

shown above in the form of Demand Draft from a Nationalised/Scheduled Bank preferably having

its branch at lmphal (Non-refundable) and drawn in favour of Deputy General Manager, Stores

Division, MSpDbL, Yurembam, lmphal. A self addressed envelope of Size (250X350 mm) with

sufficient postal Stamps duly affixed on it for sending the Tender Paper by SPEED POST or

REGISTERED POST'for areas not covered by the Speed Post should be accompanied with

request for purchase of Tender Papers. Tender Papers can be downloaded from the website

wr11;r/v manipur.gov.in but the cost of Tender Paper should be submitted at the time of

submission of completed Tender. Completed Tenders without cost of the Tender paper shall

not be accepted.

Any delay/loss/non-receipt of the request for purchase of Tender papers or of the Tenderpapers soiOlissueO or also non submission of completed Tenders due to postal delay or any

other reasons not attributable to the Company shall not be the responsibility of the Company and

no time gxtetfsion of these grounds shall be entertained.-/

TenderSpecification No

Particulars Qnty. Cost ofTenderPaper

Last date ofreciept ofcompleted

Tender

Due date ofopening of

Tender

2t1114 Distribution Transformer100KVA, 1110.433 KV, 3

Phase, 50 HZ, DY11,ONAN, (three star ratingsof BEE) Aluminium wound,complete with accessories,fittings and 1st filling of oilconforming to lS:1180(Part-1, Part-ll) and lS2026 or its latest version

50 Nos Rs. 500/- 14t3t141.00 P.M.

151311411.00 A.M.

2t2t14 Distribution Transformer63KVA, 1110.433 KV, 3

Phase, 50 HZ, DY1 1,

ONAN, (three star ratingsof BEE) Aluminium wound,complete with accessories,fittings and 1st filling of oilconforming to lS:1180(Part-1, Part-ll) and lS2026 or its latest version

50 Nos Rs.500l 14131141.00 P.M.

151311411.00 A.M.

The MSPDCL reserves the right to reject any or all the Tenders or accept any Tender infull or part thereof without assigning any reasons whatsoever. The last date of Sale/lssue ofTender Paper and also the last date of receipt of Tender/Due Date of the tender happens to beholiday, the same shall be postponed on the next working day at the same place and time.

Copy to:- 1.

MSPDCL

The Secretary to the Hon'ble Chief Minister, Manipur, for kind information ofthe Hon'ble Chief Minister.The Commissioner (Power), Govt. of Manipur for favour of information.The Executive Director(Tech), Manipur for information please.The General Manager, Electrical Circle No. - l/ll/lll for information pleaseThe Deputy General Manager, Stores Division, Yurembam, MSPDCL, forinformation. He is advised to deposit the required amount to the DIPR forpublication of the NlT.The General Manager(Finance), MSPDCL, Manipur.The OSD, Department of lnformation Technology, Govt. of Manipur. He isrequested to hoist the above NIT to the State Government website.

2.3.4.5.

6.7.

lSudhan)

TERMS AND CONDITIONS

Specification NoLast date of submission of TenderDue date of Opening of Tender

ITEMS:-st.No.

Particulars Qnty.

1. Distribution Transformer 100KVA, 1110.433 KV, 3 phm(three star ratings of BEE) Aluminium wound, complete with accessories, fittingsand lstfilling of oilconforming to ls: 1180(part-1, part-ll) and lS 2026or its lateltversion

50 Nos

2 Distribution Transformer 63KVA, 1110.433 KV, 3 pm(three star ratings of BEE) Aluminium wound, complete with accessories, fittingsand lstfilling of oilconforming to ls: 1180(part-1, part-ll)and ls 2026or its lateltversion

50 Nos

1. Offers in Triplicate should be sent on their letter heads.

2. Offer should be submitted in Triplicate in sealed envelope duly superscribed TenderSpecification No., 'Date of opening' and description of items distincly addressed to theGeneral Manager(PPP), MSPDCL Manipur, lmphal- 795001

3' Tenders will be received upto 1.00 P.M. of 141312014 and will be opened on 1St3l2O14 at11.00 A.M' in the presence of the intending tenderers ortheir authorised representatives. lf thelast date for receipt and due date of opening of tenders happens to be a holiday, offers shall bereceived and opened on the next working day at the respective appointed hours.

4' The Department reserves the right to postpone the date of opening of tender of a situationso arises to warrant its postponement.

5' Ordinarily, firms should send their offers by registered/speed post. However, if any firmprefers to deliv_ery his offer by hand, the same should be done through an authorisedrepresentative. Offers throuqh telegram or FAX shall not be entertained.

6- Any delay/loss/non-receipt of the completed offer due to postal delay or any other reasonshall not be the responsibility of the undersigned and no time extension oh thes" grounds shallbe allowed.

7 '1 Offer should inter-alia be accompanied by (i) Technical particulars including the guaranteedones (ii) Test Certificates of similar materials/equipment. (iii) Certificate of ISO/tSl anl 1iu; proofdocuments of reliable, genuine and reputed manufacturer etc.

7 '2 The tenderer shall furnish list of past supplies along with the names of the purchasers,Order No. & Date, quantity and Performance certificates isiued by the various clients. Details ofmanufacturing facilities/capacityiTools & Plants, testing facilities etc, shall also be furnishedalong with the offers.

8. Offers should invariably be accompanied by:-

(a) Earnest Money calculated @25% of the total quoted value subject to a maximum ofRs.20,000/- for the quoted value below.Fixed Deposit ReceipUBank DrafVBank Guarantee payableat a branch of Nationalisedischeduled Bank in lmphal duly pledged in favour of the

'Deputy

pele3l Manager, Store Division, Yurembam, Manipur. ihe firms registered withN.s.l.c./D.G.s.&D & s.s.l.(Manipur) Units only are, however, exempted depositing the

Contd. P/2

2t1t14 & 2t2t14 dt 20-01-1414-03-14 upto 1.00 P.M.15-03-14 at 11.00 A.M.

Earnest Money subject to the production of valid registration

-(2)-(b) The tenderer shall submit the quotation in two sealed covers marked as 1st and

2nd cover. The first cover should contain the Gost of Tender Form (for those Tenderer whodown loaded the Tender documents from Website) Earnest Money & Technical bid. Earnestmoney should be in the form of Demand DrafllFixed Deposit Receipt/Bank Guarantee(valid for atleast 6 months in the standard format of schedule Bank or Nationalised Bank (Guaranteed by theReserve Bank of lndia) drawn in favour of the Deputy General Manager, Store Division,Yurembam, MSPDCL, Manipur or NSIC/DGS&D/SSl (Manipur) valid registration certificate dulyattested by a Gazetted Officer of State or Central Government in case of firms exempted fromEarnest Money Deposit. The 2nd cover containing the Financial Bid/offer will not be opened, ifthe prescribed documents/Earnest Money Deposit is not found in the 1st cover and Technicalqualifications are not fulfilled. Completed Tenders without cost of the Tender paper shall notbe accepted.

(c) Valid lncome Tax and Sales Tax Clearance Certificates from the concerned authoritiesduly attested.

(d) Copies/Photocopies of the relevant documents duly attested by a Gazetted Officer ofState or Central Government.

9.1 The rates should be quoted both in figures and words along with the following break up:(i) Ex-work(ii) Excise Duty @ o/o

(iii) (a) C.S.T. (b) L.S.T.@ o/o

(iv) Any other Tax/Duty (specify)(v) Packing, Fonrarding, Freight,

lnsurance charges taken together(vi) Any other charges(Specify)

Rs. per unitRs. per unitRs. per unitRs. per unit

Rs. per unitRs. per unit

NOTE:- The offers which do not contain the above details are liable to be summarilvreiected.

9.2 Tenderers should quote only "FIRM" price. No variable price shall be considered

10. Offers submitted by the Manufacturers of the items with ISO Certificate or lSl Certificate orboth shall be given preference.

11. Tenderers should note that number/quantity may be increased or decreased at the time ofplacement of the order.

12. ln the case of failure to execute the order within the stipulated time, penalty @ 1l2olo perweek subject to a maximum of 10o/o of the total value of the machine/equipment undelivered/delivered late shall be imposed. However, in case of delay by 3 months or more, the order maybe cancelled and the Security Deposit will be forfeited, without prejudice to any other action thatmay be taken under law. The imposition of penalty is, however, subject to force MajeureConditions.

13. Force Majeure: The force majeure conditions shall be such, acts of God, acts of Publicenemy, Fire, Flood, Epidemic, Strike, Freight embargo, Earthquake, Labour unrest, Wars,lockout, Civil Commotion, Cyclone, Government regulation etc.. lf the progress or delivery is

delayed due to the above happenings during the delivery period then the delivery period will beextended only to the extent of the time lost, provided notice of such happening issued by acompetent authority is given within 30 (thirty) days from the date of happening.

14. Successful firm(s) shall have to make a minimum Security Deposit calculated @ 10o/o of thetotal order value subject to a maximum of Rs.5.00 Lakhs before the commencement of thesupply.

Contd. P/3

t

-(3)-

15. Delivery:- The machine/equipment should be dispatched and delivered by road on freightpaid basis through a Nationalised Bank approved Road Transport Agency having their branch orhead office at lmphal, duly insured against any loss or damage in transit. The Freight andlnsurance charges should include Loading, Unloading and Handling charges and be paidin advance by the supplier before delivery at the consignee's godown/stockyard atlmphal. Delivery of the machine/equipment should be completed within 6 (six) months from thedate of receipt of the technically and commercially cleared order.

16. Payment: 100% payment shall be made after receipt of the machine/equipment in fulland in good conditions at the consignee's Godown/stockyard at lmphal and onsubmission of necessary documents.

17. Guarantee:- The machine/equipment shall be guaranteed for a period of 18 (Eighteen)months from the date of supply or 12 (Twelve) months from the date of commissioning,whichever is earlier.

18. The machine/equipment shall be made available for inspection afterthe order is awarded,to an authorised representative of the Department during manufacture or before despatch.

19. Tenders from firms who have not purchased tender documents from the Department willnot be considered.

20. 3(three) Sets of technical & descriptive literature with relevant drawing/ catalogues of thedetails of the equipment shall be submitted with the tender.

21. Tender paper is not transferable.

22. The tenderer must offer for full quantity of the machine/equipments failing which the offershall be considered as non-responsive.

23. Offers which are not accompanied by the required earnest money will be summarilyrejected.

24. The Department reserves the right to accept any offer and reject the lowest or any otheroffer without assigning any reason whatsoever and the right to split the order, if required.

25. Any firm which does not fulfill the above terms and conditions may be summarily rejected.

26. Legal Jurisdiction: All disputes relating to this NIT will be settled within the legaljurisdictionof lmphal only.

1.0

TECHNICAL SPECIFICATION FOR OUTDOOR TYPEDISTRIBUTION TRANSFORMERS

OUTDOOR TYPE TH REE-PHASE 1 1KV I 433-250V DISTRI BUTI ON TRANS FORMERS:

SCOPE

This specification covers the design, manufacture, testing at works, supply, delivery,erection, testing and commissioning of oil immersed, naturally cooled, three-phase, 50Hz, double-wound, outdoor type distribution transformers of capacities 63, 100, and 250KVA and, for use on systems with nominal voltages of 11 KV on HT side. Any otherparts not specifically mentioned in this specification but othenruise required for properfunctioning of the equipment should be included by the tenderers in the offer. Unlessothenryise modified in this specification, the distribution transformers shall comply withthe latest versions of lndian Standard Specifications lS:1180 (Part-|, Part-ll) andlS:2026.

STANDARD RATINGS

The standard ratings shall be, 63, 100 and 250 kVA.

STANDARDS

The transformer/materials shall conform in all respect to the relevant lndian/lnternationalStandard Specification, with latest amendments thereof, some of them are listed below:

lndian Standard Title lnternational&lnternationally

recognized standard

1.1

2.0

2.1

ts-1180

ts- 335/1983

lS-3639:1968

l5-2026:1977-81 SpecificationforPower tEc- 76TransformerOutdoor Distribution Transformerupto and including 100kVA

lnsulating Oil for transformer & BS -148SwitchgearFittings & Accessories for Power ASTM D-1275transformer

lS-2099:1986 High Voltage Porcelain Bushings IEC 296-1969lS- 7421-1988 LowVoltage Porcelain Bushings

lS-3347 Dimensions for Outdoor Bushings DIN 42531 to 33

lS-12444 Specification for Copper wire rods ASTM B-49

ts-5484 Specification for Aluminum wire ASTM 8-233rods

lS-5/1961,no. 632 Specification for colours for readymixed paints

ts-6600/1972 Guide for loading of oil immersedTransformers

REC Specification D-1473,D-1533-193439, 1993CBI&PPublication, ManualontransformerNo.275

ASTM D-1275

3.0

4.0

Material conforming to other internationally accepted standards, which ensure equal orhigher quality than the standards mentioned above would also be acceptable. ln casethe Bidders who wish to offer material conforming to the other standards, salient pointsof difference between the standards adopted and the specific standards shall be clearlybrought out in relevant schedule. Four copies of such standards with authentic Englishtranslations shall be furnished along with the offer.

SERVICE CONDITIONS

The Distribution Transformers to be supplied against this Specification shall be suitablefor satisfactory continuous operation under the climatic conditions as per 15:2026 (Part -l) or latest revision and as indicated in the General Technical Requirements (GTR).

PRINCIPAL PARAMETERS

The transformer shall have core type construction and shall be suitable for outdoorservice as step down transformer. The electrical parameters of the transformer shall beas follows:

1) Rated HV voltage2) Rated LV voltage3) Connection (HV)4) Connection(LV)5) Vector Group6) Tap changer7) Tap range

8) Material of winding9) Type of cooling

10) Method of system earthing

1 1kV433-250 voltsDeltaStarDYnl 1

Off-loadTapping shall be provided onHV winding. Range shall be+5% to -5o/o in steps of 2.5o/o

Copper, double wound typeONANSolidly earthed system

5.0 NO.LOAD VOLTAGE RATIOS

The no-load voltage ratios shall be as follows:

1 1000/433-250 V for capacity of 63,100 and 250 kVA

TEMPERATURE RISE

The transformer shall be capable of operating continuously at its normal rating withoutexceeding the temperature rise limit. The temperature rise shall not exceed the limits of55' C (measured by resistance) for transformer windings and 450C (measured bythermometer) in top oil when tested in accordance with lS: 2026.

The limit of temperature rise mentioned above will have to be satisfied by the bidder bycarrying the Heat run test at the lowest negative tap by feeding losses corresponding tothe rated current of the tap.

LOSSES & LEBELLING

It is mandatory that Transformers having rating from 63 and 100 KVA shall be 3 Star asper the BEE specifications and shall be labeled accordingly as per the gazettenotification dated 617109 of BEE.

The maximum allowable losses at rated voltage and rated frequency permitted al75degree centigrade for 1110.433 KV Transformers shall be as per 3 Star rating as perBEE, however rating wise no load losses shall be limited to the values as under.

6.0

6.1

6.2

7.0

7.1

8.0

st.No.

Rating in KVA lron losses inwatts

Total losses at50% Loadino 100% Loadinq

1 63 150 380 12502 100 200 520 1 800

These losses are maximum allowable and there would not be any plus tolerance.However, the manufacturer can offer losses less than above. The offer will be evaluatedas perthe loss evaluation formula given in REC, K-5 Standard-1997 as amended uptodate. Loss capitalization factor for Rural and Urban areas may be taken as follows.

RuralArea:Capitalised cost of DT = lnitial cost of DT + 72157 * Wl +15009 * Wc + 28863 . Wp

Urban Area:Capitalised cost of DT = lnitial cost of DT + 108235 * \Nl +44160 * Wc + 43294* \Np

Where: Wl = lron loss in KWWC = CoPPer loss in KWWP = Auxiliary loss in KW

The no load loss in KW at the rated voltage and frequency and the load loss in KW atrated voltage, rated frequency, rated output and at 75 degree centigrade shall be quotedand these figures shall be guaranteed"

IMPEDANCE

The recommended percentage impedance at 750C is 4.5o/o or as specified by the ownerin the BPS subject to a tolerance as per lS: 2026. No-load current at 100% voltage shallnot be more than 1.5o/o of the full load current and shall be subject to tolerance as perlSS" No load current al12.5o/o over-voltage should not exceed 5%" The supplier shallfurnish necessary design data in support of the calculations.

WINDING CONNECTIONS AND VECTORS

The primary (HV) windings shall be connected in Delta and the secondary (LV) windingin Star (Vector system DYnl 1) so as to produce a positive displacement of 300 from theprimary to secondary vectors of the same phase. The neutral of secondary windingsshall be brought out to a separate insulated neutralterminal.

HV windings shall consist of maximum 4 coils per limbs. All delta leads from HT coils aswell as HT line leads should be taken cut through DPC, copper wires of sufficient cross-sectional area to impart desired mechanical strength. The current density in these leadsshould however not exceed O.8A/sq.mm. All the above leads should be taken outthrough Bakelite tubes.

The winding shall be so designed as to produce minimum out of balance forces in thetransformers.

The winding shall be so designed such that all the coil assemblies are of identicalvoltage ratio and shall be interchangeable and repairing of the winding could be madeeasily without special equipment.

The conductor used in the coil shall be best suitable to the equipment and all thepermanent current carrying joints in the winding and leads shall be properly sleeved andcrimped instead of jointing with solder of welding. All HV-& LV coil ends shall be

9.0

9.1

9.2

9.3

9.4

provided with crimped lugs.

9.5

9.6

10.0

11.0

DPC insulation shall be used for wires of HV & LV windings. Kraft paper in laye(s) oftotal thickness of not less than 4 mm shall be used for interlayer insulation, OpC andKraft paper used shall be of uniform density and free from any ioreign particle. The endturn of each layer shall be properly and fully covered to avoid interlayer flashover. Thecraft paper used for this purpose shall be in conformity with lS:OgalSO (paper forelectrical purpose) and latest amendment thereof. Dovetailed spacers shail be usedbetween the section of HV windings. Corrugated cylinder made from pre-compressedinsulation Board should preferably be used between LV&HV windings. ihe insulation ofcoils shall be vacuum impregnated in oil to develop the full electiical strength in thewindings. All material used in the insulation and assembly of the winding shall beinsoluble non catalytic and chemically inactive in the hot trinsformer oil anJ shall notsoften or otherwise be adversely effected under operating conditions.

Alternatively in place of vacuum impregnation, the core and coil assembly shall be fullydried out in 'Air Drying oven' till the coils are shrunken to the designed level and arecompletely dried only then they will be impregnated in the transformei oil.

Minimum gap of 2.5mm shall be maintained between the end coils and core.

TRANSFORMER OIL

The transformer shall be supplied complete with first filling of oil and insulating oil shallcomply with the requirements of lS:335/1983 with latest version thereof or BS:148 orREC 39/1993. Oil shall be filled under vacuum.

INSULATION RESISTANCE OF WINDINGS

The minimum insulation resistance values in Mega Ohms between winding and earthwhen the transformer is filled with oil should be:

lnsulation resistance between winding and earth

2ooc 30oc (t"?3,3nt)

sooc 6ooc

HV winding

LV winding

2000

800

1 000

400

500

200

250

100

125

50

'12.0

12.1

The insulation resistance values (HV windings) should be measured with a 2500 VMegger, preferably motorized of a repute make.

FITTINGS AND ACCESSORIES

Common for all Distribution Transformers

(a) Two earthing terminals

(b) Oil level gauge indicating three positions of oil, marked as follows:

o Minimum (-s oC)

. 30oCo Maximum (gg oC)

(c) Lifting lugs/Platform lugs

(d) Rating and terminal marking plate(s)

(e)

(f)

(g)

(h)

(i)

Silica gel breather of approved design & should contain min. 0.5k9.Dehydrated silica gel (ref clause pertaining to conservator also)

Thermometer pocket

Air Release Plug

OTI for 250 kVA and above

Filling hole having P 1-114 thread (with cover) on the transformerbody/conservator.

Plain Rollers

Off circuit tap changer switch handle should be provided with lockingarrangement

Drain and top filler valves

(i)

(k)

(t)

13.0 TANK CONSTRUCTION (Gommon for alltypes)

13.1 The tank shall be of rectangular shape with round edges and be fabricated from testedquality of mild steel of adequate thickness i.e. minimum 3.15 mm. (for side walls) and5.00 mm. (for top & bottom plates).

13.2 To meet the variation of pressure inside the tank, due to variation in temperature andshort circuit current, the tank shall be suitably stiffened. The stiffeners be provided on allthe four side walls of the tank,

13.3 The transformer tank shall be fitted with ERW elliptical tube/pressed steel radiators.Heat dissipation calculation in respect of number, size & length of radiators are to beproved by design calculation.

13.4 The tank cover shall be slightly sloping towards HV bushing.

13.5 The transformer tank shall be complete with all accessories, satisfactory lifting lugs andshall be designed as to allow the complete transformer tank, filled with oil to be lifted bycrane or jacks etc without risk of any damage and transported by Rail/Road withoutstraining any joint and without causing leakage of oil.

13.6 The transformer tank shall be fitted with skids. All skids shall be provided with four axleholes of 40mm. diameter (for shaft of 38mm. plain roller).

13.7 Sealing gaskets

13.7.1 All sealing washers/gaskets shall be made of 'oil and heat resistant' Nitrile / Neoprenerubber/synthetic rubber bonded cork type RC-70C gaskets. Gaskets made of naturalrubber or cork sheet are not permissible.

13.7.2 The oil level in the transformer shall be made up to the required level while thetransformer filled with all is maintained at a temperature of 45 Deg. C.

13.7.3 The exterior of the transformer tank and other ferrous fitting shall be thoroughly cleaned,scrapped and given a priming coat and two finishing coats of durable oil and weatherresisting paint.

13.7.4 All steel screws, nuts and fasteners exposed to atmosphere shall be either galvanised orcadmium plated. lt shall be mentioned in Technical Particulars.

14.0 SURFACE PREPARATION AND PAINTING OF TANK

14.1 Steel surface shall be prepared by sand/shot blast or chemical cleaning includingphosphate as per lS:3618. The MS fittings may preferably be electrogalvanised,

14.2 Heat resistance and antioxidant paint (Hot oil proof) shall be provided inside the tank.

14.3 On external surface one coat of Thermo setting powder paint or two coats of zincchromate followed by two coats of synthetic enamel paint of dark admiral gray shadeconforming to No.631 of lS-5 of 1961 shall be provided.

15.0 CONSERVATORS

15.1 Provision of conservator is obligatory.

15.2 When a conservator is fitted, the oil gauge and the plain breathing device shall be fixed

to the conservator which shall also be provided with a drain plug and a filling hole with acover. ln addition, the cover of the main tank shall be provided with an air release plug

to enable trapped air to be released unless the conservator is so located as to eliminate

the possibility of air being trapped in the main tank.

15.3 The inside diameter of the pipe connecting the conservator to the main tank shall be

within 20 to 50 mm and it should project into the conservator in such a way that its end

is approximately 20 mm above the bottom of the conservator, so as^to create a sump forcollection of impurities. The minimum oil level (corresponding to -50 C) should be above

the sump level. Breather pipe should be connected at top of the conservator tank with

two bends at right angles.

16.0 RADIATORS

These shall be made of ERW elliptical tubes with minimum side thickness of 18 SWG.

These elliptical tubes should be of best quality and should be used in verticularformation without any bending and properly welded on both ends to common headers. lt

should be individually tested for leakage and pressure tests etc., before welding with themain tank.

17.0 RATING AND TERMINAL MARKING (PLATE(S))

Each transformer shall be provided with non-detachable rating and terminal markingplate(s) of weather proof material, fitted in a visible position and showing the complete

information as given under clause 17 of lS:1 180 (Part-l) - 1 981 '

18.0 CORE CONSTRUGTION

18.1 The design of magnetic circuit shall be such as to avoid static discharges developmentof short circuit paths within itself or in the earthed clamping structure and the production

of 1ux components at right angles to the plane of laminations which may cause local

heating.

18.2 Every care shall be exercised in the selection, treatment and handling of core steel toensure that as far as possible the laminations are plain and the finally assembled core is

free from distortion, burrs and bends.

18.3 Each lamination shall be insulated such that it will not deteriorate due to mechanicalpressure and the action of hot transformer oil.

Cold Supernon-agtng,18.4 The core shall be constructed either from high grade,Grain Oriented silicon steel laminations conforming to g or r or from

amorphousmetal.Theamorphouscoreshallbeofhighqualityamorphousribbonshaving very low loss formed into wound cores of rectangular shape and clamped

together by frames firmly to prevent vibration or noise. The maximum flux density in any

part of the cores and yoke at normal voltage and frequency shall be such that the flux

density with 12.5 % vottage variation fromlhe voltage shall not exceed 1.9 Tesla' The

bidder snafi provide satu-ration curve of the core haterial proposed to be use and

calculations.18.5 The complete design of core must ensure permanency of the core losses with

CoNTINUOUS WORKING of the transformers. The value of the flux density allowed in

the design and grade of lamination used shall be clearly stated in the offer'

1g.6 All parts of the core shall be of robust design, capable of withstanding any shocks to

which they may be subjected during hand-ling, lifting, transportation installation and

service. Cfamplng of core and winding- assemOly with tank should be done by angle iron

pieces, welded tJtank walls and not to be done with flat iron pieces.

1g.T Adequate arrangement shall be provided to enable the core and winding to be lifted'

{9.0 CoNSTRUCTIONAL FEATURES-Common for All type of DTs

1g.i Bushings arranqement The transformer shall be fitted with three high voltage and four

tow vottagfiffiiffiEbushing of appropriate.voltage and current rating. The HV and

LV terminars ousrringshall haviporcelain bushings. The bush.ing rod shall be of brass'

Each terminal includ'ing the neuiral shall be distinctly marked and coloured for phase

voltage on both HV an-d LV sides. The system of marking shall be in accordance with

the rJquirements of lS 1 180:1964 amended todate'

The electrical characteristics of high voltage bushing shall conform. to latest version of

ls:2ogg and ls 3347.The low voftige bushlng shall conform to latest version of ls:7421.

All porcelain bushing shall be homogeneous free from other flaws effecting its

mechanical strengtn'or dielectric qualily. These should be well vitrified, tough and

impervious to moisture.

l,g.2 Bushins terminals : To avoid bimetallic action at the point of connection to the

aluminiumftFFffidings and to the external aluminium cables/conductors, both HV &

LV ous6ing--Jtemi sha-ll be made of aluminium alloy/copper conforming to the

requirements of lS: 3347.

19.3 The bushing terminals shall be clamp type to directly .. receive aluminium

conductors/cables without requiring use of tugs. tne terminals shall be directly screwed

ontothestemtosecureeffectivesealingofthebushing.

20.0 BASE MOUNTING ARRANGEMENT (Common for alltypes)

The under base of alltransformers shall be provided with two 75x40x6mm channels with

holes (at a centre to centre distance of 41Smm) to make them suitable for mounting on

platform or Plinth.

21.0

21.1

CLEARANGES (Common for alltYPes )

External

The external electrical clearance between phase to phase and phase !o ea{h to provide

adequate .r""p"g"-Jistance in accordance with Clause 7.1 of lS:2099 shall not be less

than the values given below:-

Voltage Medium Glearance Phase toPhase (mm)

Glearance Phaseto earth (mm)

11 kV

433 V

Air

Air

255

75

205

55

21.2 lnternal

22.0

22.1

l. Minimum internal clearance between inner walls

of tank and core coil assembly unit shall be as under:-

(a) On length side(b) On width side

ll. Radial clearance between HV & LV winding(bare conductor clearance)

lll. Phase to Phase clearancebetween H.V. limbs (Live Part)

lV. Minimum clearance from top of yoke to the

inside of the toP cover of tank

V. Minimum clearance of LV

coilto core (mm)

Vl. Minimum GaP between H'V.coils (Horizontal duct)

Vll. Minimum clearance for HVcoil to lower and uPPer Yoke

Vlll Minimum clearance betweencore and tank bottom

40 mm25 mm

11 mm

10 mm

120 mm

5.0 mm

8.0 mm

25 mm

40 mm

The aforesaid external and internal clearances are minimum clearances and no

negative tolerance on these clearances shall be allowed.

TESTS (Common for all type of transformers )

Routine Tests: All transformers shall be subjected to routine tests at the manufacturer's

works in accordance with lS: 2026 and lS: 1180 (Part-l). The following tests are to be

carried out:

(a) Measurement of winding resistance

(b) Measurement of voltage ratio and check of voltage vector relationship

(c) Measurement of impedance voltage/short circuit impedance and load-loss

(d) Measurement of no-load loss and current

(e) Measurement of insulation resistance

(f) lnduced over-voltage withstand test

(g) Separate-source voltage withstand test

(h) Oil samPle test -^ /?(-=-- - i (-----A//\/'\

22.2

23.0

The supplier shall furnish calculations in accordance with 15:2026 to demonstrate the

thermaiability of the transformers to withstand short-circuit.

TEST VOLTAGE (Gommon for all type of transformers )

Transformers shall be capable of withstanding the power frequency and impulse

test voltage Prescribed below:

Nominal systemvoltage

Highestvoltage

lmpulse testvoltage

Power frequencYvoltage

12 kV (rms) 75 kV (Peak)3 kV (rms)

28 kV (rms)

24,0 INSPEGTION

a) all tests and inspection shall be made at the place of manufacture unless especially

agreed upon OV ine manufacturer and purchaser at the time of purchase' The

manufacturer shall afford the inspector representing the purchaser all reasonable

facilities, without charge to satisfy him that the material is being furnished in accordance

with this specification.

b) The purchaser has the right to have the test carried out at his own cost by an

independent agency whenevei there is a dispute regarding the quality of supply.

25.0 PACKING

Transformer shall be delivered suitably packed. Although the method of packing is left to

the discretion of the manufacturer it should be robust enough for rough handling that is

occasioned during transportation by road'

All accessories shall be dispatched in boxes or cases. They shall be securely bound

with wire and shall have all descriptive marking stamped thereon'

433 V (rms)11kV (rms)

26.0 GUARANTEEDTECHNICAL PARTICULARS

The guaranteed technical particulars of thegiven by the tenderer along with the tender'

offered shall be

General nager(PPP)MSPDCL

st. No. PARTICULARS

I 2 3

1 Name of Manufacturer2 Standard lS:1180/64 ,2026fi962

&3639/66

3 Service4 KVA Ratino:-a) HV Windinqb) LV Windinq5 Rated voltaqea) HV Windinqb) LV Windinqb Rated frequency7 No. of ohases8 Connectionsa) HV Windinqb) LV Windinq9 Connection symbol10 Taooino11 Tvpe of coolinq12 Temperatures rise ina) Too Oilb) Windinq13 Total loss at rated voltage on principal

tappino and at rated frequency14 Reference ambient TemPeraturesa) Maximum ambient air temperatureb) Maximum daily average ambient air

temoeraturec) Maximum yearly weighted average ambient

temperatured) Minimum ambient air temPeraturee) Maximum cooling water temperature15 Comoonent Losses:-a) No load loss at rated Voltage on principal

taooino and rated frequencyb) Load loss at rated Current at principal tapping

at 75" C16 lmpedance Voltage at rated Current for the

orincioal tappino:-a) HV-LV17 Reactance at rated Current and rated

freouencv18 No load Current at rated voltage and rated

Freouencv19 lnput to Coolinq plant

GUARANTEED TECHNICAL AND ADDITIONAL TECHNICAL PARTICULARS FOR

DISTRIBUTION TRANSFORM ERS

(To be furnished by the Manufacturer for each rating separately)

a--\ /\ '\ /(---->{

-l' \\15\

Contd/P-2

-(2)-

20 Requlation at full load at 75 oC

a) At unitv power factorb) At 0.8 power factor lagging21 lnsulation level:-a) Separate source power frequency withstand:-

i) HV Windinqii) LV Windinqb) lnduced over voltage withstand:

HV Windinqii) LV Windinq at 100H2c') Full wave liqhtninq impulse voltage'-i) HV Windinsii) LV Windinq22 Eff'rciencv at 75 oC at Unity pewgflectgla) At full loadb) At % full loadc) At % full load23 Equipment for ONAN cooling

Radiators on Main Tank24 Terminal arranqement

Hish voltage (HV)ii) Low voltaqe(LV)iii) Neutral25 Aooroximate Masses:-a) Core and winding (kg)

b) Tank and fittinqs with Accessorleg-(lg)c) oild) Total Masse) Aooroximate oilqtY in litresf) Tolerence26 npproximate overall dimensions of the

Transformer27 Thickness of main tank cover/Side/Bottom

olates28 Dispatched details29 Reference standard30 Tolerance

MSPDCL

LIST OF FITTINGS AND ACCESSORIES TO BE PROVIDED WITH 63 & 1OO KVA 1110.4 KVTRANSFORMER

Sl. No. Particulars1 Two earthing terminals

2 Oil level gauge indicating three position of oil marked as minimum - 5 degree C, 30degree C & Maximum 98 degree C

3 Lifting lugs

4 Rating and terminal marking plate

5 Silica gel breather

6 Drain cum sampling valve

7 Thermometer pocket

8 Filling hole with cover on Transformer's body

I Bimetallic terminal connection on the HV/LV bushings.