G3IR-1050-65-SP-9031_R1

Client Name : BASF India Limited Project Name : Project GIR Project Number: G3IR

Specification G3IR-1050-65-SP-9031 Date 18-Jul-12

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66 kV Instrument Transformer

G3IR-1050-65-SP-9031_R0 Page 1 of 12

Project Document No: G3IR-1050-65-SP-9031

Unit: General Discipline: Electrical Document Type: Specification

Document Title: SPECIFICATION FOR 66 kV INSTRUMENT TRANSFORMER

1 30-Jul-12 Issued for Design HS NG VP

0 18-Jul-12 Issued for RFQ HS NG VP

Fluor BASF Revision Date Purpose Prepared By Checked By

Approved By

ISSUED FOR DESIGN08 Aug 2012



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Record of Revisions

This specification has been revised as indicated below and described in the revision record on the following page. Please destroy all previous revisions.

Revision

No. Date Description

0 18-Jul-12 Issued for Design (RFQ)

1 30-Jul-12 Issued for Design



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TABLE OF CONTENTS

1.0 GENERAL.................................................................................................................................................. 4

1.1 SCOPE....................................................................................................................................................... 4

1.2 REFERENCES........................................................................................................................................... 4

1.3 SERVICE CONDITION .............................................................................................................................. 5

2.0 TECHNICAL REQUIREMENTS ................................................................................................................ 5

2.1 GENERAL.................................................................................................................................................. 5

2.2 CURRENT TRANSFORMERS (CTs)........................................................................................................ 6

2.3 VOLTAGE TRANSFORMERS (VTs) ........................................................................................................ 7

2.4 MARSHALLING BOX................................................................................................................................ 8

3.0 INSPECTION AND TESTS........................................................................................................................ 8

3.1 66kV VOLTAGE TRANSFORMER ........................................................................................................... 8

3.2 66 kV Current Transformer...................................................................................................................... 9

4.0 SPARE PARTS.......................................................................................................................................... 9

5.0 FITTINGS AND ACCESSORIES............................................................................................................... 9

6.0 SUPPORT STRUCTURE......................................................................................................................... 10

7.0 DRAWINGS AND DOCUMENTS ............................................................................................................ 10

ANNEXURE-A

(SPECIAL REQUIREMENTS FOR DGVCL METERING INSTRUMENT TRANSFORMERS) ........................ 11



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1.0 GENERAL

1.1 SCOPE

1.1.1 This specification is intended to cover design, engineering, procurement,

manufacture, inspection and testing at manufacturer’s works, packing, loading,

forwarding, transport and delivery to site, erection / installation, testing and

commissioning at site of isolator suitable for current and voltage transformers for

outdoor use.

1.1.2 For specific requirements of tariff metering VT and CT, please refer to Annexure-A

for details. Whatever arrangements / modifications required to be done to meet

the requirements mentioned in the annexure shall be responsibility of supplier.

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

construction of the equipment. However, all components shall conform in all

respects to high standards of design engineering, materials of construction,

workmanship and shall also be in line with the current practice for reliable and

efficient functioning of the equipment and be capable of performing in continuous

commercial operation in a manner acceptable to the Owner.

1.1.4 Supplier is required to carefully examine and understand the specifications and

seek clarifications, if required, to ensure that he has understood the specifications

as intended by the Owner. In the absence of any specific clarifications made by

the Owner during bidding stage, the interpretation of Owner shall be final. The

Supplier’s offer should not carry any sections like clarifications, interpretations

and/or assumptions. All such points are required to be clarified during bidding

stage.

1.2 REFERENCES

1.2.1 The instrument transformers and the associated equipment shall conform to the

latest editions of following standards issued by BIS (Bureau of Indian Standards)

and IEC unless otherwise specified. Each publication shall be the latest revision

and addendum in effect on the date this specification is issued for Purchase,

unless noted otherwise. Except as modified by the requirements specified herein

or the details of the drawings, as a minimum, work included in this specification

shall conform to the applicable provisions of these publications:



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S.No. Description IS/IEC

1 Specification for current transformer IS-2705 (Part I to V)

2 Application guide for current transformer. IS-4201

3 High voltage porcelain bushings IS-2099

4 Hollow insulator for use in electrical equipment IS-5621

5 Specification for Voltage transformer. IS-3156 (Part I to IV)

6 Application guide for voltage transformer. IS-4146

7 Specification of electric power connectors IS-5561

8 PVC insulated cables up to & including 1100 volts.

IS-1554

1.2.2 In case of any contradiction between various referred standards/specification/data

sheets and statutory regulations, it shall be brought to the notice of Client for

resolution. Generally the following order of priority shall govern,

Statutory regulations

BASF Guidlines

Data Sheets

This specification

Codes and standards

1.3 SERVICE CONDITION

1.3.1 The instrument transformers shall, in all respects, be suitable for operation under

the service conditions stated in the RFQ.

1.3.2 The instrument transformers shall be fully stabilized thermally to give a life

expectancy of twenty five (25) years under site conditions and take care of effect

of direct solar radiation. Periodic maintenance interval shall be greater than 5

years.

2.0 TECHNICAL REQUIREMENTS

2.1 GENERAL

2.1.1 The instrument transformers shall be hermetically sealed units. The instrument

transformers shall be provided with filling and drain plugs.



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2.1.2 The instrument transformers i.e. current and voltage transformers shall be single

phase transformer units and shall be supplied with a common marshalling box for

a set of three single phase units.

2.1.3 Polarity marks shall indelibly be marked on each instrument transformer and at

the lead terminals at the associated terminal block.

2.1.4 The parameters for the CT's and VT's are given in the following clauses shall be

reviewed during detailed engineering based on the burden and other calculations

to be furnished by the Bidder during detailed engineering.

2.2 CURRENT TRANSFORMERS (CTs)

2.2.1 The CTs shall be capable of withstanding the dynamic & thermal stresses and

short circuit current at 31.5 kA for 1 sec.

2.2.2 The CTs shall have single primary of bar type with following requirements:

The secondary shall be totally encased in metallic shielding providing a

uniform equi-potential surface for even electric field distribution.

The upper part of insulation assembly sealing on primary bar shall be

properly secured to avoid any damage during transportation due to

relative movement between insulation assembly and top dome.

The insulator shall be one piece without any metallic flange joint.

The lowest part of insulation assembly shall be properly secured to avoid

any risk of damage due to transportation stresses.

2.2.3 The core lamination shall be of cold rolled grain oriented silicon steel or other

equivalent alloys. The cores shall produce undistorted secondary current under

transient conditions at all ratios with specified parameters.

2.2.4 CT shall be oil-filled, self cooled, hermetically sealed type. CT shall be provided

with oil level gauge and pressure relief device. An inert gas cushion shall be

maintained on top of the oil.

2.2.5 CT shall be single phase unit, designed for upright mounting on steel structure

and furnished complete with anchoring hardware. Insulator shall be wet process

porcelain, brown glazed and free from imperfections. All metal parts and

hardware shall be hot dip galvanised.



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2.2.6 Different ratios (if applicable) shall be achieved by secondary taps only, and

primary reconnections shall not be accepted.

2.2.7 The guaranteed burdens and accuracy class are to be intended as simultaneous

for all cores.

2.2.8 The secondary terminals shall be terminated on stud type non-disconnecting

terminal blocks inside the terminal box of degree of protection IP: 55 at the bottom

of CT. The terminal box should be weather proof and dust-tight, complete with

gasketed front access cover and removable gland plate at bottom for cable entry

2.2.9 The CTs shall have provision for taking oil samples from bottom of CT without

exposure to atmosphere to carry out dissolved gas analysis periodically.

Contractor shall give his recommendations for such analysis, i.e. frequency of

test, norms of acceptance, quantity of oil to be withdrawn, and treatment of CT.

2.2.10 The winding shall be suitable for simultaneous 100% full load continuous rating.

The winding shall be capable of desired output as per specified limit.

2.2.11 Rating of the CT shall be as per the single line diagram attached with the RFQ.

Supplier to submit the VA burden calculation report for owner’s approval.

2.3 VOLTAGE TRANSFORMERS (VTs)

2.3.1 The VT shall be capable of withstanding the dynamic and thermal stresses of

short circuit current of 31.5 KA for 1 sec. without any damage or deterioration.

There shall be no radio interference when the equipment is operated at maximum

service voltage. The safety clearances of all live parts of the equipment shall be

as per relevant standards.

2.3.2 VT shall be oil-filled, self cooled, hermetically sealed type. VT shall be provided

with oil level gauge and pressure relief device. An inert gas cushion shall be

maintained on top of the oil.

2.3.3 VT shall be single phase unit, designed for upright mounting on steel structure

and furnished complete with anchoring hardware. Insulator shall be wet process

porcelain, brown glazed and free from imperfections. All metal parts and

hardware shall be hot dip galvanised.

2.3.4 The maximum temperature in any part of the equipment at specified rating shall

not exceed the permissible limits as stipulated in the relevant standards.



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2.3.5 Rating of the VT shall be as per the single line diagram attached with the RFQ.

Supplier to submit the VA burden calculation report for owner’s approval.

2.4 MARSHALLING BOX

2.4.1 The wiring diagram for the interconnection of three phase instrument transformer

shall be pasted inside the box in such a manner so that it is visible and it does not

deteriorate with time.

2.4.2 Terminal blocks in the marshaling box shall have facility for star/delta formation,

short circuiting and grounding of secondary terminals. The box shall have enough

terminals to wire all control circuits plus 20 spare terminals.

3.0 INSPECTION AND TESTS

The current and voltage transformers shall confirm to type tests and shall be subjected to routine

and type tests in accordance with the relevant IEC/IS. Following is the list of tests (not limited to)

which vendor shall be perform:

3.1 66kV VOLTAGE TRANSFORMER

3.1.1 Type test reports for the following tests shall be submitted for EHV Voltage

Transformer

Temperature rise test

Chopped impulse test

EMC radio Interference Voltage tests, if applicable

Short Circuit Withstand Capability test

Lightning impulse test

Wet test

3.1.2 Routine Tests: The following Routine test shall be conducted under this contract :

Capacitance and tan d measurement at power-frequency

Power Frequency withstand test

Measurement of Partial discharges

Verification of terminal markings

Power-frequency withstand test on the L.V terminal



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3.2 66 kV Current Transformer

3.2.1 Type test reports for the following tests shall be submitted for EHV Current

Transformer

Temperature rise test

Short time current test

Switching impulse voltage test

Lightning impulse test

Wet test for outdoor type transformers

Radio interference voltage measurement

3.2.2 Routine Tests: The following Routine test shall be conducted under this Contract:

Power Frequency withstand test on primary winding

Power Frequency withstand test on secondary winding

Power Frequency withstand test between sections

Measurement of Partial discharges

Verification of terminal markings

Accuracy Check (Determination of errors)

Ratio Test

4.0 SPARE PARTS

Bidder shall submit list of spares recommended by him for satisfactory operation of the circuit

breakers for first two (2) years and rate for each spare shall also be quoted. The owner shall

decide the actual quantity of spare parts to be ordered on the basis of the prices of the spare

parts, quoted by the bidder.

5.0 FITTINGS AND ACCESSORIES

a) Each CT shall be furnished complete with the accessories as listed below:

1. Base frame with anchoring bolts, nuts etc. for fixing the equipment on to structure.

2. Two grounding pads with bolts and spring washers.

3. Lifting Lugs.


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4. Clamp type bimetallic terminal connectors.

5. Weather-proof secondary terminal box with set of terminals.

6. Grading ring, if necessary.

7. Oil level gauge and pressure relief device.

8. Oil sampling valve.

9. Spark gap arrangement

10. Nitrogen sealing hole cover

11. Other standard accessories which are not specifically mentioned but are required

with current transformers of such type and rating for efficient and trouble-free

operation and make the installation complete.

b) Each VT shall be furnished complete with the accessories as listed below :

1. Base frame with anchoring bolts, nuts etc. for fixing the equipment on to structure.

2. Two grounding pads with bolts and spring washers.

3. Lifting Lugs.

4. Clamp type bimetallic terminal connectors.

5. Weather-proof secondary terminal box with set of terminals and 3 nos. HRC

fuses.

6. Grading ring, if necessary.

7. Oil level gauge and pressure relief device.

8. Other standard accessories which are not specifically mentioned but are required

with voltage transformers of such type and rating for efficient and trouble-free

operation and make the installation complete.

6.0 SUPPORT STRUCTURE

For steel support structure specification, refer Doc. No. G3IR-1050-65-SP-9042 attached with

RFQ.

7.0 DRAWINGS AND DOCUMENTS

The Vendor shall furnish drawings in accordance with SDDC form, enclosed with the Bid.




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ANNEXURE-A

SPECIAL REQUIREMENTS FOR DGVCL METERING INSTRUMENT TRANSFORMERS

1. The DGVCL metering shall be located in the switchyard nearest to CTs and EMPTs in the

Weatherproof MMB / SMC box with adequate sealing arrangement.

2. All the CTs and EMPTs must be provided with Stainless Steel Bellows & No Noitrogen gas

filling or Rubber Gasket will be acceptable in case of 66 kV class of voltage.

3. For multi ratio CTs:

(i) The selection of ratio must be provided only on secondary of the CTs.

(ii) The value of ISF shall have to be certified for each ratio of the metering core.

4. The copy of all the type test certificates in respect of sample CT and EMPT as per specified

under CI. No. 9.1 .1 of IS-2705 (Part-I) for CTs and CI No. 9.1.1 of IS-3156 (Part-I) of similar

class of accuracy, similar design, rating and technical specification conducted on proto type

sample by the supplier at any Govt. or Govt. approved test house (not later than (FIVE years

before the HME of submission of certificates), shall have to be submitted at DGVCL Corporate

office for necessary approval before procurement / placement of procurement orders. Failing

to submit the above Type test certificates any subsequences arise after placement of order /

procurement without the approval, shall have to be borne by the supplier.

5. All the CTs produced and to be installed / used for tariff metering purpose shall have to be got

tested at ERDA-Vadodara for all routine tests, as specified under CI. No. 9.1.2 of IS-2705

(Part-1), including the test of ISF as per CI. No. 7.1.2 of IS-2705 (Part-2). The original copy

with one zerox copy of ERDA Routine Test Certificates along with the ERDA test certificate for

ISF test shall have to be submitted at DGVCL Corporate Office for final approval before actual

commissioning of the CTs at connection site. Also the copy of OGA drawing, Name plate

drawing and the secondary terminals drawings of the above CTs shall have to be submitted

along with the ERDA test certificates in case of CTs & supplier's Acceptable test certificates

(witnessed by GETCO officer) in case of EMPTs for final approval.

6. The supplier shall have to arrange routine testing of all EMPTs at manufacturer's works as

specified under CI . No. 9.1.2 of IS-3156 (Part-1). The acceptance tests will be witnessed by

concern GETCO officer at supplier's works . The accuracy test on PT shall not be conducted

with simultaneous burden of all cores, instead the tariff metering core shall be tested

separately for 10 VA and 2.5 VA burden i.e. as per CI. NO. 5 of IS-3156 (Part-II). The original




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copy with one zerox copy of supplier's Acceptance test certificates (witnessed and signed by

GETCO officer) shall have to be submitted for final approval before actual commissioning of

the same. the supplier shall also have to submit copy of OGA drawing, Name plate drawing

and secondary terminal/ box drawing for necessary approval along with the Acceptance tests

certificates .

7. Supplier shall have to intimate SE (TR) of concern GETCO circle, seven days in advance for

deputation of concerned Engineer for witnessing the Acceptance tests at their supplier works.

8. Supplier shall have to obtain necessary approval from the GETCO Corporate office in respect

of 66 KV SLD, its protection system , PLCC / VHF system and 66 KV Switch Yard and also

necessary approval from the Chief Electricity Commissioner of E&P Dept., GOG before actual

commissioning of the switch yard.

Documents

G3IR-1050-65-SP-9031_R1