16461-dry type transformer

7/27/2019 16461-Dry Type Transformer

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B. Operation and Maintenance Instructions: The contractor shall furnish datacovering model, type and serial numbers, capacities, maintenance and operationof each major item of equipment or apparatus in accordance with therequirements of the contract documents. Operating instructions shall cover allphases of control.

C. Test Reports: The contractor shall submit test reports to the Engineer for review.

D. Recommended Spare Parts List: The contractor shall submit recommendedspare parts list to the Engineer for review.

E. As Built Drawings: The contractor shall submit the as built drawings to theEngineer for review and approval.

1.4 QUALITY ASSURANCE

A. All materials and products shall be new, sound and uniform in quality, size,

shape, color and texture and shall be free from defects. The work shall be carriedout in accordance with this specification, the contract drawings and the standardslisted hereunder. The codes and standards specified herein provide anacceptable level of quality for materials and products. Equipment shall conformto the Altitude of site.

B. The work shall be carried out in accordance with this specification, the contractdrawings and the standards listed herein. The referenced codes and standardsprovide an acceptable level of quality for materials and products:

C. The contractor shall be responsible for ensuring that the required standards ofquality control as mentioned in relative sections are maintained for the proposed

transformers.

D. If requested by the Engineer, the supplier shall provide proof of application of aquality procedure complying with standards. This means:

1. Use of a quality manual approved and signed by a managementrepresentative,

2. Regular updating of this manual so that it reflects the most recentapplicable quality control procedures,

3. ISO 9002 certification.

E. The manufacturer must have a sound experience in the field of transformers for

not less than ten years, and should have a presentable reference list of thealready supplied equipment of the same type and same make and that thisequipment has been in satisfactory operation in Kingdom of Saudi Arabia for atleast three years.

1.5 COORDINATION

A. The contractor shall be held responsible for the proper coordination of all phasesof the work under this contract.

B. It shall be the responsibility of the contractor to coordinate the work andequipment as specified herein with work to be performed and equipment to be

furnished under other sections of the specifications in order to assure a completeand satisfactory installation.

ITCC in RiyadhResidential ComplexJ10-13300

16461-2 Dry-Type Transformers


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1.6 TRANSPORTATION, HANDLING AND STORAGE

A. Deliver, store, protect and handle products to site as per manufacturersinstructions.

B. Store transformers in clean and dry space. Inspect for damage. Maintain factorywrapping or provide an additional heavy canvas or heavy plastic cover to protectunits from dirt, water, construction debris and traffic.

C. Lift only with lugs provided for the purpose. Handle carefully to avoid damage totransformer internal components, enclosure and finish.

1.7 WARRANTY

A. Submit written guarantee signed by the contractor and manufacturer for the periodof one year from the date of substantial completion. The guarantee shall cover therepair and replacement of defective materials and workmanship as directed by theEngineer.

PART 2 - PRODUCTS

2.1 GENERAL

A. The following specifications apply to three-phase transformers of cast resin type,class F insulation system with natural (AN) cooling for indoor installation,destined for use in three-phase MV/LV distribution systems.

B. Indicated transformer rating is for natural cooling an ambient temperature of 50C.

C. Transformer shall be designed to allow for forced cooling (AF) if required forcedcooling shall increase the transformer capacity rating by 40 %.

D. Include all equipment (fans, control. etc) necessary for forced cooling andcommunication (MODBUS) interface for a fully functional system.

2.2 GENERAL REQUIREMENTS

A. General

1. The transformer shall be of climatic class C2 and of environmental classE2 as defined in appendix B of HD 464 S1: 1988 / A2: 1991. C2 and E2classes shall be indicated on the rating plate.

2. The transformer shall be of fire behaviour class F1 as defined in article B3of CENELEC HD 464 S1: 1988 / A2: 1991. F1 class shall be indicated onthe rating plate.

B. Magnetic Core

1. This shall be made from laminations of grain oriented silicon steel,

insulated with mineral oxide and shall be protected against corrosion witha coat of varnish.




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C. LV Windings

1. These shall be made from copper foil with class F interlayer insulation byencapsulation (impregnation) with synthetic alkyd resin or equivalent.

2. At least the upper part of the LV coils shall be covered with a coat ofepoxy resin or equivalent and the foil shall be protected everywhere withan insulation material even in the air ducts.

D. MV Windings

1. These shall be independent of the LV windings and shall be made ofcopper wire or foil (according to the manufacturer's preference) with classF insulation.

2. The MV windings shall be vacuum cast in a class F fireproof epoxy resin

casting system composed of:

- An epoxy resin- An anhydride hardener with a flexibilising additive- A flame-retardant filler

3. The flame-retardant filler shall be thoroughly mixed with the resin andhardener. It shall be composed of trihydrated alumna powder (oraluminum hydroxide) or other flame-retardant products to be specified,either mixed with silica or not.

4. The casting system shall be of class F.

E. MV Connections

1. The MV connections shall be made from above on the top of theconnection bars. Each bar shall be drilled with a 13-mm hole ready forconnection of cable lugs on terminal plates.

2. The MV connection bars shall be in rigid copper bars protected by heatshrinkable tubing.

3. MV connections in cables are not allowed.4. The MV connections shall be copper.

F. LV Connections

1. The LV connections shall be made from above onto bars located at thetop of the coils on the opposite side to the MV connections.

2. Connection of the LV neutral shall be directly made to the LV terminalsbetween the LV phase bars.

3. The LV connection bars shall be copper and shall accept busway or cableas shown on drawings.

G. MV Tapping

1. The tapping which act on the highest voltage adapting the transformer tothe real supply voltage value, shall be off-circuit bolted links.

2. Tapping with connection cables is not allowed.3. These bolted links shall be attached to the MV coils.




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2.3 METAL ENCLOSURE

A. The transformers shall be equipped with a metal enclosure for indoor installationcomprising an integral IP 31 (except the base which may be IP 21) metalenclosure with:

4. An anti-corrosion protection in the manufacturer's standard color.5. Lifting lugs enabling the transformer and enclosure assembly to be

handled.6. A bolted access panel on the enclosure front to allow access to the MV

connections and to the tapping. This shall be fitted with handles; it shallhave one "Danger Electricity" warning label (T 10 warning), a rating plateand a visible braid for earthling.

7. Blanked off holes for fitting key locks on the bolted access panel toenable it to be locked.

8. 2 UN-drilled gland plates on the roof: one on the MV side, one on the LVside (drilling and cable gland not supplied).

9. 1 plate at the right MV side on the bottom of the enclosure for the MVcables for connections from the bottom.

2.4 ACCESSORIES AND STANDARD EQUIPMENT

A. The transformers shall be equipped with:

1. 4 flat bi-directional rollers2. 2 lifting lugs3. Haulage holes on the under base4. 2 earthling terminals

5. 1 rating plate6. 1 "Danger Electricity" warning label7. 1 routine tests certificate8. 1 instruction manual for installation, commissioning and maintenance in

English.

B. Thermal protection

1. The transformers shall be equipped with a thermal protection device,which shall comprise:

- 2 sets of 3 PTC sensors, one sensor for "Alarm 1", one for "Alarm 2" perphase, installed in the coils of the transformer. They shall be placed in a

tube to enable them to be replaced when ever necessary.- An electronic converter with two independent monitoring circuitsequipped with a changeover switch, one for "Alarm 1" and the other for"Alarm 2". The position of the relays shall be indicated by differentcolored indicator lights. A third indicator light shall indicate the presenceof voltage.

2. The three indicator lights shall be on the front of the converter. Theelectronic converter shall be installed away from the transformer.

3. A plug-in terminal block shall be provided for connection of the PTCsensors to the electronic converter.

4. The PTC sensors shall be supplied assembled and wired to the terminalblock fixed on the upper part of the transformer. The converter shall be

supplied loose with the transformer, packaged complete with its wiringdiagram.




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C. Forced Air Cooling

1. Transformers shall be equipped with cross flow cooling fans. These fanswill increase the rated output of the transformer up to 40% and have lownoise levels and ideal long time control of irregular overloads.

2. Thermal sensors automatically control the fans, avoiding excessive andunnecessary use of the cooling fans.

2.5 TYPE TESTS AND ROUTINE TESTS

A. Routine Tests

The following tests shall be carried out on all the transformers after themanufacturing, enabling an official test certificate to be produced for each one:

1. Measurement of windings resistance.

2. Measurement of the transformation ratio and vector group3. Measurement of impedance voltage and load loss4. Measurement of no load loss and no load current5. Applied voltage dielectric test6. Induced voltage dielectric test

(All these tests shall be in accordance with Harmonisation Document HD 464 S1,the IEC 60726 and IEC 60076-1 to 60076-5 standards).

B. Type Tests Special Tests

The following tests may be requested by the Engineer:

1. Temperature rise test carried out in accordance with the simulatedloading method as defined by the IEC 60726 standard.

2. Lightning impulse test.3. Short circuit test.4. Noise level measurements in accordance with IEC 60551.5. Measurement of partial discharges.

For measurement of the partial discharges, the acceptance criterion shall be:

- Partial discharges less than or equal to 10 pC at 1.10 Um.If Um > 1.25 Un (Un = rated voltage, Um = system highest voltage), then the

10 pC are guaranteed at 1.375 Un.

(All these tests shall be in accordance with Harmonisation Document HD 464 S1,the IEC 60726 and IEC 60076-1 to 60076-5 standards).

1. The climate and environmental tests shall be performed in accordance withappendix ZA and ZB of CENELEC HD 464 S1: 1988 / A3: 1992.

2. The fire behaviour test shall be performed in accordance with appendix ZCof CENELEC HD 464 S1: 1988 / A3: 1992.

2.6 TRANSFORMER TECHNICAL DATA




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For each requested transformer, the supplier shall give the following data :

Rated power @ 50%...........................................................As per drawings KVACooling.....................................................AN or AF (as shown on drawings)Rated frequency........................................................................................60 HzPrimary voltage.......................................................................................13.8 KVRated primary insulation level................................................................17.5 KVPower frequency withstand Voltage(rms) .................................................38 KVBasic Insulation Level (BIL) or impulse withstand voltage (peak)..............95 KVOff-circuit tapping................................................................................+/- 2.5 %Secondary voltage at No- Load

- For 400V system, No-Load Voltage : 400V- For 230V system, No-Load Voltage : 231V

Vector group.......................................................................................Dyn11

No load losses............................................................................................... WLoad losses at 75 C..................................................................................... WLoad losses at 120 C................................................................................... WRated impedance voltage at 120 C.............................................................. %Acoustic power Lw(A).................................................................................... dB(A)Acoustic pressure at 1 meter Lp(A)............................................................... dB(A)

Maximum ambient temperature.................................................................50 CDaily average ambient temperature..........................................................37 CYearly average ambient temperature............................................................ CMaximum altitude.......................................................................................... m

MV winding temperature class...................................................................... FLV winding temperature class....................................................................... FTemperature of insulation system................................................................. 155 C

Climatic classification (HD 464 S1)................................................................ C2Environmental classification (HD 464 S1).................................................... E2Fire behaviour classification (HD 464 S1)..................................................... F1

Enclosure...................................................................................................... YESProtection degree.......................................................................................... IP 31

Length........................................................................................................... mm

Width............................................................................................................. mmHeight............................................................................................................ mmTotal weight................................................................................................... kg

Measurement circuit supply voltage for the thermal protection electronicConverter.........................................................................................DC AC V

PART 3 - EXECUTION

3.1 WORKMANSHIP




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A. Materials, products and equipment furnished by the contractor, shall be installedand all work shall be performed in a first-class workmanship manner, inconformity with the best trade practices and the printed directions of theapplicable manufacturers; by skilled workers equipped to produce satisfactoryresults; in a safe, substantial manner so as to avoid undue stresses, rigid enoughto prevent undue movement, so as to present a neat, orderly appearance and tofacilitate operating, servicing, maintenance and repairing.

3.2 FOUNDATIONS AND SUPPORTS

A. The contractor shall provide concrete pedestals, anchor bolts, hangers,channels, saddles, etc., for installation of equipment and apparatus shown on thedrawings and specified in the various sections.

3.3 EQUIPMENT ERECTION

A. All electrical equipment shall be installed in accordance with the manufacturer'srecommendations, good electrical engineering practice, and the relevantdrawings and specifications.

B. All metal surfaces to be bolted shall be thoroughly cleaned before assembly.The connections shall be tightened with manual torque wrenches to themanufacturer's erection instructions. Ground equipment according to Section16452 GROUNDING.

C. Splices shall be implemented to ensure the electrical continuity of the horizontalbusbars, auxiliary buses and the proactive conductor between adjacent sections.

D. It shall be possible to secure the sections to a floor that is flat by anchoring

directly to a concrete floor using anchor bolts or by securing to ordinary metalprofiles.

3.3 EQUIPMENT TESTING AND COMMISSIONING

A. After the installation is complete and properly adjusted, the contractor shallconduct operating tests. The various equipment and systems shall bedemonstrated to operate in accordance with the requirements of the contract

documents. Tests shall be performed in the presence of the Engineer. Thecontractor shall provide electric power, instruments and personnel necessary forperforming the various tests.

B. The testing of all electrical equipment shall include, but not be limited to, theitems below. This shall be in addition to testing specified elsewhere in thisspecification.

1. General equipment check.2. Field wiring and ground system verification.3. Equipment adjustment.

END OF SECTION



16461-dry type transformer

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