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Frequent Questions & Answers for

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1 Frequent Questions & Answers for
Global Energy Solutions Frequent Questions & Answers for DuPontTM ReliatraN® Version1 dated June,2003 PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

2 Contents What is ReliatraN® page 5 ~ 6 Global Energy Solutions
ReliatraN® Criteria page 7 What is NOMEX®? page 8 ~ 15 What are the major advantages of page 16 ReliatraN ® Brand Transformers ? What are the benefits to the users of page 17 How does DuPont maintain the high quality page 18 ~ 20 and reliability of ReliatraN® transformers? How does ReliatraN® perform under moisture? page 21 ~ 27 PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

3 Contents Global Energy Solutions
How does ReliatraN® perform under dirty condition? page 28 ~ 29 What’s the meaning of load loss by various insulation class? page 30 ~ 33 How is dielectric withstand of ReliatraN® ? page 34 ~ 35 How well does ReliatraN® perform during overloading? page 36 ~ 37 How well does ReliatraN® withstand short circuit ? page 38 What is the fire behavior of ReliatraN® ? page 39 ~ 45 PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

4 Contents Global Energy Solutions
How is ReliatraN® environmentally friendly ? page 46 ~ 48 What does partial discharge mean to dry type transformer ? page 49 What is VPI process ? page 50 ~ 51 What is the maximum rating of ReliatraN® transformers? page 52 Index page 53 PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

5 Global Energy Solutions
What is ReliatraN® ? ReliatraN® is poised to be the chosen brand for value-added transformer solutions that apply to various distribution transformer applications. PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

6 Providing Global Energy Solutions to the Electrical Industry
DuPontTM ReliatraN® Brand Transformers are manufactured with UL® Certified Insulation Materials , by a global network of ISO 9001 Certified Manufacturers, meeting the highest of International Standards for Quality, Design, Construction and Performance DuPontTM ReliatraN® is a Trademark of E. I. DuPont de Nemours and Co. PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

7 DuPontTM ReliatraN® Criteria
Global Energy Solutions DuPontTM ReliatraN® Criteria The ReliatraN® standards are continuously reviewed to incorporate new experience, materials, test procedures, etc or to adapt new requirements PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

8 What is NOMEX® ? The superior electrical properties of NOMEX®
Global Energy Solutions What is NOMEX® ? The superior electrical properties of NOMEX® paper and pressboard provide unique capabilities for electrical equipment, resulting in new classes and ratings. This includes: High Level of Safety Increased Load Capability Reduced Size and Weight Long Term Reliability PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

9 NOMEX® Electrical Insulation has been used
Global Energy Solutions NOMEX® Electrical Insulation has been used in the most critical applications in all types of electrical equipment. Resin Cast Transformers Ventilated Dry Transformers Generators Reactors AC/DC Motors Gas Filled Transformers Liquid Immersed Transformers Hermetic Motors PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

10 The Advantages of NOMEX®
Global Energy Solutions The Advantages of NOMEX® The unique capabilities of materials made from Nomex® aramid polymer are a result of it’s superior Thermal, Chemical, Mechanical and Electrical properties PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

11 The Advantages of NOMEX®
Global Energy Solutions The Advantages of NOMEX® THERMAL Long Term Stability up to 220°C Short term exposures up to 350°C is possible Stable properties over a wide range of temperature and humidity conditions Will not Melt, Flow or Support Combustion below 250°C, with no toxic or corrosive Off-Gases below 750°C NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co. PERFORM WHEN THE HEAT’S ON

12 N C H O The Advantages of NOMEX® CHEMICAL
Global Energy Solutions The Advantages of NOMEX® No weak C-H bonds creates a strong resistance to chemical attack by acids and alkalis Compatible with all oils, resins, varnishes, fluorocarbons, refrigerants CHEMICAL N C H O n PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

13 The Advantages of NOMEX®
Global Energy Solutions The Advantages of NOMEX® MECHANICAL High tensile strength and tear resistance prevent manufacturing problems High abrasion and cut resistance prevent production and operational failures Good compression resistance provides a stable and rigid structure during short circuit or other mechanical stresses PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

14 The Advantages of NOMEX®
Global Energy Solutions The Advantages of NOMEX® ELECTRICAL The low Dielectric Constant enables better distribution of stresses between the insulation and the cooling medium The low Dissipation Factor, even at high temperatures, reduces dielectric loss High Resistivity at high temperatures up to 250°C in use Excellent Dielectric Strength under 50/60Hz and under impulse conditions PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

15 The Advantages of Nomex®
Nomex® is a DuPont Registered Trademark Nomex® is a DuPont Registered Trademark

16 What are the major advantages of DuPontTM ReliatraN® Brand Transformers ?
These State-of-the-Art ventilated dry type transformers provide the best solution in reliable and versatile equipment Safe equipment which can be placed close to the load Flexibility in variable load situations Increased overload emergency capability Reduced Size and Weight for better space utilization Economical solutions for the distribution of power ReliatraN® is a Trademark of E. I. DuPont de Nemours and Co. PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

17 What are the benefits to the users of DuPontTM ReliatraN® Brand Transformers ?
Highest Quality Standards DuPont standards for design and manufacture exceed the local and global standards to ensure high quality and reliability / long life Longest Warranty DuPont’s network of qualified manufacturers of ReliatraN® transformers offer unprecedented five (5) years warranty Cost Savings Lowest total owning cost from purchase to disposal over the lifetime of the equipment ReliatraN® is a Trademark of E. I. DuPont de Nemours and Co. PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

18 How does DuPont maintain the high quality and reliability of DuPontTM ReliatraN® transformers?
DuPont provides the most updated technology on design,manufacturing and testing to partners and continuously monitors and audits all aspects of production to deliver quality without any failure. Simple processing enables OEMs to produce constant quality and reliability. All processes are visible to detect any potential defect of transformer. ReliatraN® is a Trademark of E. I. DuPont de Nemours and Co. PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

19 Coil Manufacturing Process
Cast coil VDT Coil Manufacturing Process Assemble mold - Preheat resin - Sophisticated process/ many parameters to quality impact Weigh resin - Simple process/ less parameters to quality impact - Mix resin pouring Impregnation(VPI) curing drying - Disassemble mold

20 One of the special requirements for the transformer
installed at Nuclear Power Plant is longer life ( 40 years). VDT had been used in many Nuclear Power Plants in US due to reliable long life Failure rate of VDT at field is less than half of that of other dry transformers in US. ReliatraN® is a Trademark of E. I. DuPont de Nemours and Co. PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

21 How does DuPontTM ReliatraN® perform under moisture?
NOMEX® itself has high resistance under high humidity. VPI processing assure that windings are well protected against harsh environment such as moisture and dust. Many tests and historical cases at operation sites have proved that VDTs were safe to operate without outage at high humid conditions. ReliatraN® is a Trademark of E. I. DuPont de Nemours and Co. PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

22 If a dry type transformer is energized after long storage period under high humidity,it is recommended either to wipe dirt and moisture or to energize without loading before placing a load on transformer. We do not recommend starting or operating a transformer with free moisture on the coils as there may be surface deposits that are conductive when wet. ReliatraN® is a Trademark of E. I. DuPont de Nemours and Co. PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

23 Relative Volume Resistivity of Materials (ohm - cm)
1020 1016 1012 108 100 10-6 10-10 } Insulators Semiconductors Conductors Superconductors Nomex® 50°C 220°C { Nomex® is a DuPont Registered Trademark Nomex® is a DuPont Registered Trademark

24 } { Relative Volume Resistivity of Materials (ohm - cm) 1020 1016 1012
108 100 10-6 10-10 } Insulators Semiconductors Conductors Superconductors Epoxy Resin 50°C 100°C 150°C { Nomex® is a DuPont Registered Trademark

25 Superior Humidity Resistance *
Relative Dielectric Dissipation Volume Humidity Constant Factor Resistivity (%) (60 Hz) (60 Hz) (ohm- cm) _____________________________________________________ Dry * Properties for Nomex®10 mil (0.25 mm) T-410 Nomex® is a DuPont Registered Trademark Nomex® is a DuPont Registered Trademark

26 Moisture resistance of VDT insulated with NOMEX®
A 1000KVA ventilated dry type transformer with NOMEX® insulation was used in a special moisture demonstration by exciting the transformer at full voltage immediately after being in a thunderstorm. Transformer description It is 1000KVA rated volts primary and 480Y volts secondary. The temperature rating is 150C rise at a max. ambient of 40C. The BIL rating of the high voltage is 95KV. The prior history of the transformer includes a short circuit test and impulse test following the short circuit test. The transformer was then subjected to higher impulses and subsequently flashed over at 138 KV. The partial discharge inception voltage when tested as individual coils was 1.9 times rated voltage at 400 Hertz excitation. The Demonstration The transformer was placed outdoors during an extremely severe thunderstorm. The thunderstorm lasted about one hour and 1.5 inches of rain fell. Immediately there after, the transformer was brought to the testing area and excitation was applied. The transformer withstood its full operating voltage with no sign of imminent flashover. Nomex® is a DuPont Registered Trademark Nomex® is a DuPont Registered Trademark

27 Moisture resistance of VDT insulated with NOMEX®
Conclusion The NOMEX® insulated ventilated dry type transformer with VPI treatment exhibits superior moisture resistance and can be used in outdoor locations in a properly designed outdoor enclosure. The thunderstorm demonstration was performed to show the superior moisture resistance of coil construction. Case study by Southern Transformer Co. Alexander D.Kline,President Nomex® is a DuPont Registered Trademark Nomex® is a DuPont Registered Trademark

28 How does DuPontTM ReliatraN® perform under dirty condition?
Coil structure is well constructed to separate each disk, which will not allow cumulative dust collection between disks. Enough cooling space in LV, gap between LV/HV and HV ensure effective cooling even at harsh environment such as cement plants and mines One ASEAN power utility has operated several VDTs for more than 15 years without any maintenance at all, though a thick layer of dust covered windings. ReliatraN® is a Trademark of E. I. DuPont de Nemours and Co. PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

29

30 What’s the meaning of load loss by various insulation class?
The higher insulation class makes it possible to build smaller size of coils, eventually leading to smaller transformer size. The one of the advantages of H class dry type transformer is compactness and lower no load loss with more load loss compared with other transformers below H class. ReliatraN® is a Trademark of E. I. DuPont de Nemours and Co. PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

31 Therefore, higher temperature designs more fully utilize
Most of transformers operate at significantly below the full rated load(average 60%) which benefits lower no load loss in terms of economic view. Therefore, higher temperature designs more fully utilize the raw materials and optimize losses, which is the growing trend in the West. Reliatran® can be built for specific load loss, lower than standard class H transformer by request. ReliatraN® is a Trademark of E. I. DuPont de Nemours and Co. PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

32 0.94

33 Temp. Coil Size Comparison Class (% of Class H) Class B 130
Higher winding temperatures allow smaller coils and smaller magnetic cores, saving cost, space and weight. Temp Coil Size Comparison Class (% of Class H) Class B 130 Class F 115 Class H 100 Class C PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

34 How is dielectric withstand of DuPontTM ReliatraN® ?
Due to lower dielectric constant of NOMEX® than other insulation materials, It has better distribution of stresses throughout transformer There is no thick layer of Epoxy resin which means “No cracking” on coils. One of the common problems with cast coil is cracking to cause failure. Disk winding structure distributes the voltage stress evenly and efficiently to meet BIL requirement of all standards. ReliatraN® is a Trademark of E. I. DuPont de Nemours and Co. PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

35 NOMEX® Brand Paper & Pressboard
The Dielectric Constant of NOMEX® sheet insulation is very low compared to most insulating materials. Nomex® Air Inorganics Mineral Oil 2.2 Glass Silicone Epoxy Cellulose The closer to the cooling medium(air), the better the distribution of stresses throughout the transformer. Nomex® is a DuPont Registered Trademark Nomex® is a DuPont Registered Trademark

36 How well does DuPontTM ReliatraN® perform during overloading?
Based on GB standard, the average winding rise is 125C and max. hottest temperature is 180C. In this case there is temperature margin which is 40C differential between thermal capability of Nomex(220C) and max. hottest temperature(180C). This contributes to higher overloading capability. For certain cases, one can put dual ratings on the name plate for flexible operation either with lower load loss or higher capacity. ReliatraN® is a Trademark of E. I. DuPont de Nemours and Co. PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

37 PERFORM WHEN THE HEAT’S ON
Steady State Loading on the Basis of test temperature rise (Quoted from ANSI C59.96-IEEE Guide for Loading Dry type distribution and power transformer) Rated average winding temperature rise For each degree C below the rated temperature rise, increase rated load by 80C 0.57% 115C 0.43% 150C 0.35% If a 1000KVA is 100C average winding temperature rise, the additional rating for over loading can be calculated. (115C - 100C) x 0.43% + (150C - 115C) x 0.35% = 18.7% ===> 1000KVA x = 1187KVA * Note: In general, ReliatraN® provides about 30% additional capability for overloading based on practical design. ReliatraN® is a Trademark of E. I. DuPont de Nemours and Co. PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

38 How well does DuPontTM ReliatraN® withstand short circuit ?
Design principles utilized for these transformers minimize axial and radial mechanical forces in case of short circuit accident. Transformers using this design have passed short circuit tests mechanically and thermally for more than 30 years (in the US). VPI process with varnish enhances mechanical strength of coils to prevent failure by short circuit accident. In addition, the disk structure in HV coil can hold winding robustly. ReliatraN® is a Trademark of E. I. DuPont de Nemours and Co. PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

39 What is the fire behavior of DuPontTM ReliatraN® ?
Aramids do not melt (hence it will not help the fire to spread) and generate little or no smoke and emit no toxic gas. Epoxy resin may emit some toxic gases when decomposed by fire such as SO2, hydrogen sulfides and halides [Ref.1] Specialty tests like CENELEC HD-464 indicate that VDT had less smoke, less weight loss, quicker self extinguishment , less support to combustion than cast coil Nomex does not support combustion and can only be burned with difficulty - even at elevated temperature (LOI >> 21%) ReliatraN® is a Trademark of E. I. DuPont de Nemours and Co. PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

40 Quoted from “Development of Insulating Systems in Distribution Transformers - Improvement of Fire Resistant Characteristic” by G.LE ROY and F.SANDOZ “Full size testing of distribution transformer behavior under fire has been possible thanks to the building by the French Coal Board Research Center (CERCHAR) of a “fire gallery” guaranteeing against all environment pollution risks” “Class H VDT: only slight effects occurred after some times - pyrolysis of the superficial varnishes and metal frame paints ---. Let us note that this good behavior is a consequence of the choice of materials done on this equipment, on the basis of systematic fire test on samples(oxygen index at various temperatures, combustion gas analysis). Class B cast coil: Contrary to class H VDT, this equipment behavior was rather disappointing and even, in some way, surprising. About 3 minutes after being exposed to fire, whilest temperature reached only about 150C , the transformer went into flames. In spite of the radiating panels being switched off, combustion self supported itself until insulating matters complete destruction. Conclusion: “ Especially the class H VDT, the only one having shown a completely satisfactory behavior during the full size fire test.”

41 ** Panels shut off owing to fire evolution
Quoted from “Development of Insulating Systems in Distribution Transformers - Improvement of Fire Resistant Characteristic” by G.LE ROY and F.SANDOZ Transformer type VDT Cast coil Silicon Ugilec T Class H(Aramid) Class B Rating(KVA): mass tank/vessel (kg): 630 400 250 250 Liquid - - 190/40 338/60 First fire occurrence (min): Fire end (min): 30 3 30 20 40 70 110 55 Total energy measured at 12 m from the fire (MJ after 40/60 min): Energy emitted by radiating panels (MJ): Transformer part in total energy (%): 225/225 600/640 700/4900 400/500 336 143 ** 336 336 <1 80 95 55 20 Combustible destruction part (%) 20 100 100 100 300 75 10 Released carbon dioxide mass(kg): Released HC1 mass(kg): Released soot And dust mass (kg): - - - 25 0.15 0.5 180 1.5 ** Panels shut off owing to fire evolution

42 Flammability of insulation materials in transformer
400 300 200 100 10 20 30 40 0.13 mmNomex 0.13 mm PET Film 6 mm Epoxy/Filler Limiting Oxygen Index vs. Temperature Temperature (°C) Limiting Oxygen Index (%) PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

43 CENELEC Norm HD-464 Testing for the European Community
1. Severe Environments [ E ] • Humidity Saturation at 50°C / 95% RH / 72 Hrs - Must Successfully pass lightning impulse, power frequency withstand voltage, and measurement of partial discharge • Saline Condensation at 93% RH / Saline Haze of NaCl / 144 hrs / Running with water - Must successfully pass overvoltage and power frequency withstand voltage

44 CENELEC Norm HD-464 Testing for the European Community
2. Thermic Impulse Test [ C ] • Thermic Impulse test from -25°C to + 100°C within 40 minutes - Must pass impulse and partial discharge tests 3. Fire Testing [ F ] • Winding subjected to pilot flame with heat source of 800°C for 40 minutes - During test, measure toxic off-gasses and smoke emission - After flame removal, measure time to extinction, and weight loss

45 NOMEX® Insulated Transformer Coil Subjected to CENELEC HD-464 Fire Test
[%] [K] Fire Test Behavior According to HD 464 Temperature Rise and Optical Transmission Factor [OTF]

46 How is DuPontTM ReliatraN® environmentally friendly ?
When disposing NOMEX® by burning or burying, it does not emit toxicity to contaminate soil and air. Therefore NOMEX® can be recycled for fuel as energy source, which was certified by European Cement plant Burying waste of epoxy resin is costly. Incineraton of epoxy is not recommended due to potential hazardous off-gases NOMEX® can be incinerated at common furnace operating temperatures. ReliatraN® is a Trademark of E. I. DuPont de Nemours and Co. PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

47 There is no waste of varnish after impregnation process while cast coil should over-prepare epoxy resin to fill cast mold with redundancy against shrinkage/leakage. The waste at mixer and cast mold should be disposed carefully not to impact environment. Cast coils leave particlulates with Epoxy resin and glass materials when disposed. These materials are not present in VDT coils. When cast coil is ground for removing sharp edges, the dust which is mixture of glass and Epoxy resin may impact comfortable environment. ReliatraN® is a Trademark of E. I. DuPont de Nemours and Co. PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

48 There are no materials in VDT coils causing allergy and itch to human body
The quantity of materials requiring disposal is significantly less than with cast resin coils (> 4 times) Compact size with lighter weight require less active parts,which contributes for energy saving and green environment. (Production of silicon steel/copper wire entails fossil fuel consumption resulting in air/water pollution.) ReliatraN® is a Trademark of E. I. DuPont de Nemours and Co. PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

49 What does partial discharge mean to dry type transformer ?
Reliatran® has a thinner layer of varnish without any possible air bubble inside and is designed to have low voltage stress far below corona inception voltage. Cast coil transformers assume the epoxy resin fill the gaps and therefore design for epoxy dielectric, assuming no air - if any air bubbles appear, there will be high stress on the air and partial discharge will develop. It may cause insulation breakdown resulting in transformer failure . ReliatraN® is a Trademark of E. I. DuPont de Nemours and Co. PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

50 What is VPI process ? This is the most evolved technology to produce high quality coils with advanced equipment and material. Impregnation is done inside tank under vacuum/pressure condition and there are no varnish drops outside tank. ReliatraN® is a Trademark of E. I. DuPont de Nemours and Co. PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

51 During curing , there is some evaporation of solventless varnish due to cross linking process between monomers and resin. The vapor is not toxic and is exhausted out by oven chimney. Varnish does not cause skin irritation or allergic reaction to people. Excess varnish can be returned to storage the tank after impregnation process without any waste. ReliatraN® is a Trademark of E. I. DuPont de Nemours and Co. PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

52 What is the maximum rating of DuPontTM ReliatraN® transformers?
VDT transformers have been produced up to 15MVA and 35KV voltage class. Most popular range of product is up to 3000KVA. In general, Power Utilities limit electricity supply to users below 10 MVA as max. due to distribution reliability and economic reasons. DuPontTM ReliatraN® is a Trademark of E. I. DuPont de Nemours and Co. PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

53 PERFORM WHEN THE HEAT’S ON
Index 1.”Safety Aspects of Using Aramid and Paper and Pressboard in Dry Type Transformer” Dr.J.W.Rothuizen/ Switzerand 2.”Development of Insulating Systems in Distribution Transformers - Improvement of Fire Resistant Characteristics” G.LE Roy/ F.Sandoz/France 3. “Moisture Resistance of Nomex - Insulated “Glazed Coils”” Alexander D.Kline/USA 4.ANSI C IEEE Guide for Loading Dry Type Distribution and Power Transformer 5. CENELEC Norm HD Specialty test for Severe Environments,Thermic Impulse and Fire ReliatraN® is a Trademark of E. I. DuPont de Nemours and Co. PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.

54 PAPER AND PRESSBOARD UL RECOGNIZED
Global Energy Solutions DuPontTM ReliatraN ® is a Trademark of E. I. DuPont de Nemours and Co. PERFORM WHEN THE HEAT’S ON NOMEX ® is a Registered Trademark of E.I. DuPont de Nemours & Co.


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