IEEE (57.~0~ 91 .. ~805702 050~351 014 ..,

IEEE Std C57.lM-1991<R-_nollttE 0i7.IlH-m8)

R«ORftized 0.1 aftAmeriun Na.riona.! Standard (ANSI)

IEEE Guide for theInterpretation of GasesGenerated in Oil-ImmersedTransformers

•

Cin'uit~ and Device!>

Communicatiun!> Tf'f.'hnuluJ.~·

•Compulpr

Eleclrumagnelit.·8 undRadiation

IEEE Power Engineering Society

Sponsored by theTransformers Committee

Industrial Applications

'. . . . . . 'Signo.ls and'. . Applications

• •IEEE

.... , .. SlanJards- .- , '.':, ;',: :!.., " . '. t. • Coordinating ..'-,'-. '-, "~' ·Conunittff.s ~. ".

PubJislHtd by th.lnstitut. of El«lricM.r>dE~En~ It><:- 345 EMf ..7tJI SfrHt. N.... Y""k, NY IOOIZ tISA

July 22, 1992

11h~ !>y '.M IIr.iTlTurE OF HECTF1CA!.. s. ELEC~"OUCS £,.r.;t'iH"S (lEHl"'p 01 22,3<>,~ I ......

IEEE (57. ),04 910 • 4B05702 0504352 TSD •

•ReooClIiud.1t lin

American National Standard (ANSI)IEEE

Std C57.104·1991(Rlln-ionllf

IEEE C57.104-1978l

•

•

IEEE Guide for the Interpretation of GasesGenerated in Oil-Immersed Transformers

1.... ·-·-· "., ·","'f"'.1 1fT '\.:" \TSponsor .}:! '. ,,"11'" ~ ,!'~' .. ~ I_t:~ ¢U..1;(¢..... .::.<..J- ...,>..J_.U'" II

Transformers Committee PT f>LN (Perscroj JCS.:l T...I;,..,..,K..:;slrokanof the ll _IEEE Power Engineering Society

Approved June 27, 1991

IEEE Standards Board

Approved November 20, 1991

American National Standards Institute

Abstract: Detailed procedures for analyzing gas from gas spaces or gas-collecting devices aswell as gas dissolved in oil arc described. The procedures cover: (l) the calibration and use offield instruments for detedingand estimating the amount ofoombustible gases present. in gasblankets above oil. or in gas detector relays; (2) the use of fixed instruments for detecting andderermining the quantity of combustible gases present in gas-blanketed equipment; (3)obtaining samples of gas and oil from the transformer for laboratory analysis; (4) laboratorymethods for analyzing the gas blanket and the gases extracted from the oil; and (5) interpret­ing the results in terms of transformer serviceability. The intent is to provide the operatorwith positive and useful information concerning the serviceability of the equipment. An e;:ll.:ten­sive bibliography on gM evolution, detection, and interpretation is included.

Keywords: gas analysis, oil, oil-filled transformers, transformer$.

The Inlllilule orEloctril:.I.nd Eloctronic. Enginoon, Int.3~S Ealll ~71h Stl"Cet, New York, NY 10017·2394, USA

Copyrillht c: 1992 by theInstiluteorEl«tliealllllcl Electronic. Engioe<>n. Inc.

All rightJ r-ese"""'d. PubLUh"d 1~pr.nl"d in th" United State. orArne";".

ISBN I_S6937·H7_9

NfJ p<>rl <J{ this publica/I"" moy ~ rtproduc~din a..y {","m.in on <lec/rank rttTi~lJ<j1"Y""'''' ort>l.M.TWi....

wilhOl.fllh~prior wrilt~n ~rmission fJ(lh~ pUb/i"h".

'I'";9M by the INSTITUTE OF ElECTRICAL S ELECTROU"; WG1NtERS (IEEE)'Sep 01 22,U 04 199b

IEEE (57.104 91 .. 4!05702 0504353 997 ..

IEEE St:a.ndariU doeuments an developed within the 'Thchnical Com­mittees of the IEEE Societies and the Standards Coordinating Commit­tees of the IEEE Standards Board. Members of the committees servevoluntarily and without compensation. They are not necessarily mem­bers of the Institute. The standards developed within IEEE represent aconsensus of the broad expertise on the subject within the Institute aswell as those activities outside of IEEE that have expressed an interestin participating in the development of the standard.Vile ofan IEEE Standard is wholly voluntary. The existence of an IEEEStandard does not imply that there are no other ways ta produce, test,measure, purchase, market, or provide other goods and services relatedto the scope of the IEEE Slo.ndard. Furthennore, the viewpointexpressed at the time a standard is approved and issued is subject tochange brought about through developments in the slate of the art andcomments received (rom users ofthe st.andard. Every IEEE Standard issubjected to review at least every five years (or revision or reaffirma­tion. When a document is more than five years old and has not beenreaffirmed, it is reasonable to conclude that its eontent&, although stillo( some value, do not wholly reflect the present state of the art. Usersare cautioned to check to determine that they have the latest edition o(any IEEE Standard.Comments (or revision o( IEEE Standards are welcome (rom any inter­ested party, regBrdless of membership affiliation with IEEE. Sugges­tions (or changes in documents should be in the form of a proposedchange of text, together with appropriate supporting etlmments.Interpretations: Occasionally questions may arise regarding the mean­ing of portionll of standards as they relate to specific applications. Whenthe need for interpretations is brought to the attention of IEEE, theInstitute will initiate action to prepl1re appropriate responses. SinceIEEE Standards represent .II consensus of all a1neemed interests, it isimportant to ensure that any interpretation hu also received the con­currence o( a balance of interests. For this reason IEEE and the mem­bers o( its technical committees are not able to provide an instantresponse to interpretation requests except in those cases where the mat­ter has previously received (onnal consideration.Comments on standards and requesta (or interpretations should beaddressed to:

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IEEE Standards documents are adopted by the Institute o( Electrieand Electronics Enl;ineers without reJ;8rd to .....hether !beir adoption rna

nvolve patents on articles, materials, or processes. Such adoption doeot assume any liability to any patent owner, nor does it assume any obli

mtion whatever to parties adopting the standards documents.

'\ by tJ>~ INSTITUTE OF Cl[CTRICo',L I. [L[CT~ICS ENGTIl[E~S (IEEEI01 22,Jto,04 19'1to

IEEE (57.10~ 9~ .. ~a05702 050~354 823 ..

Foreword

(Thh fOJ'Cword i. Dot a put of IEEE Std C57.104.1991. IEEE Guide fDr Ille tllte",...,htioD of Cue. Genorated inQil·lrnn>el"lll;td 1'l'&.ll>Ifon:nen.l

At the time that this standard was completed, the Transformers Committee had the follow·ing officers:

d. D. Bont., Chair J. H. Harlow, VICe ChairW. B. Binder, &cretary

At the time that this 6tandud was completed, the Insulating Fluids Subcommittee had thefollowing members:

B. A Pearce, Chair

D. J. AJJanH.A:t;~ian

D. B.....""w.JdJ. C. DryaD.tG. BryantJ. CorkraD.D. w.c",n.D.H.Dougl...M.Fi~r.:ld

R. M.}·..,yM.Ftydma.nP. Gel"lai.J. P. GibeaultD.A.CilliuJ. Goudie}'. M. Gragg

F. J. Grynkie....u:zT. J. HaupertF. W. Heinrich.P. J. HoeflerC.R.Hoe...!B. G.HuDterD. L.JOh"lOODJ. J. KellyJ. P. Kio....yJ. G. LackeyR.t. LoweG.O.McR_M.M.McCeeK. Mcl.hDllmOllC.K. MillerR. E. Millk..itz

F. W. Heinrichs, Secretary

R.J. Mull1W. Mutechler, Jr.E.J.NortonT.OrbeckC. T. RaymoI'dA.D.lWchult.eG.J. ReitterT.O.Rou.....L.J.SavioG. J. Schreude...D. W. Sulldio.J. A. Thomp....T. P.1....ubR.A. VeitchR. M. ViDb'ntL. Wagenaar

At the time that it balloted and approved this standard for submission to the IEEE Stan·dards Board. the Transformers Committee had the £ollowing members:

E.J.Ado1ph,oDL. C.A>cherD.J.AUanB.AUenR. AUustilU'tiS.AltmMJ. C.AmoldJ. AubinR. Ba...,ronD. BarnardD. L. BuolP. L. BellalchiS.BellDDnW. B. BinderJ. V. BonuceM.1. n. Bo..,.tC .V. BnlWDO. R. ComptonF. W.CookJ. L. Corku.nD. W.Cnlfb.J_N.O"v;"D.H.Dougl....J. C. Dt.>ttoDJ. K. E8IIle)'J.A.EbertD. J. FallonS. L. FosterM.Frydmsn

K. R. HightollP. J. HodlerC.H""""IR. H. Holli.te-rC. C.HoneyE.HowellaC. HurtyY.P.tijimaG. W.lIi1fR.G. J" ....b...nD. L. JOlu:t.lIOlID. C. JohnlonA.J.JonnattiC. P. KappelerR. B. KaufmanJ. J. KellyW. N. KennedyJ. P. KinneyB. Kl.pon,kiA. D. KlineE.KoeDlgJ. G. LackeyR. E. LooH. F. LightS. R. LindgrenL. W. Lonl("L. A. LowdermilkR. J. Lc>weM.L.MOl1luing

M.MltelmJInH. R.MooreR.J.Muli1W. H. MutllChlcrE. T. NortonR. A. 01'1100B.K. PatclW.•'. PattenonH.A. PUI'C1!D. Pc.....L. W. PlCI"Ct!IJ. M. PollittC. P. RaymondC.A Robbio.L. J. SavioW. E. SuonD. N. SharmaV.ShenoyW. W. SkinL, R. SI.ewoI&J1dE.G.Str...g...D. S\lndinL. A. SwenllOnD. S. T.kachA. M. TepliukyV. TheDappaDR. C. Tho.....J. A. Thomr-oT. P. Traub

>r tt>. ltlSTIlUTE OF ELECTRICAL.!. ELECIRONICS E~GWE(RS I IEEE I22,31>.04 !'l'lt>

IEEE (51.104 91 .. 4~05102 0504355 1bT ..

n.E.Ga~1

R. E_ Ceo.m.r.D. W.~rl..:hD.A.Gim­R. s. CiJori.R. L. GrubbF. .I. cryukie...-ic&C.RIlI.I. H. Hario....F. W. HeillJidl.w. n.lI~nnl.D.g

B. D. MItIOIiIT. M,a-wda.I. W. Matlb<twi.I. McGillC. J. McYille"W. J.Mc:NlIuS. P.M~bt.C. K. MllklrC.H.MJlli...R E. Minkwil&

D. E. TruaxW.B.UhlR. E. Uptevdf, Jr•G. H. VaiU.-..rtR.A.. Veitd.L. B. Waae--rll:. J. WhtartyA. L. WilbW. E. Wrt'DJIA. C. WII rdal:l<E.J.Yuud.

The Accredited Standar<u Committee on Transfonnera, Regulatora, and Reacton, C57, that.reviewed and approved thia document, had the following members at the time of approval:

Leo J. Savio, Chair John A. Gauthier, Secntary

Electric Ualn ."dPo..... Graul' _._P . .__... .__..P. E. Ol1lhek

S. M. Ii.. RizYiF.s...v.uJ. SltUi...."

J. C. T1w>a>pI<»)M. C. MiIIioI. WI.)

l t;l"t. of Electrical and £lor:trotUo;:a Eng;ooort .J. D. Bont

J.Davil.I. H. Hulow

hS.'"H. D. SmithR.A. V~;l.ch

Nati<loal Elec:t,-w,al Manufattu",nAaBociatio" ..__•__....._.....__....H. ._........__••• G. D. Collila'

P. I>.w",",

.I. D. DouiluA.A. Char""ri...

K.R.U".koyR. L. PI....ter

H.RDbI"R. E. Upt.egratr. Jr.

F. J. Hopkiraon Wr.)J. NayWt.)

Tennea!lOO Valley "'lIt!>ority .

U"dctwritel"'l Laboratoria, Inc ..

.. H F.A. Lewll.

.................................................................. _ W. T. O'Grldy

US Dtpal't....e"t oru...I.owrior. Bllr...u ofRecl.o.matioo F. W. Cook, Sr.

US DeP""-,,,,"llt orthe N...,., Civil EqiDHring eor,.. .__.._... . H. P. StieJUe,.

"t by t!'>. INSTITUTE Of ElECTllIt:Al. I ElECT_ICS £NGIN£ERS 1[[([1~ 01 20',3<>,001 19%

IEEE (57.104 91 _ 4t105702 0504356 6ib •

When the IEEE Standards BOl\Td approved this standJlTd on June 27, 1991, it had the fol­lowing membeTShip:

Marco W. Migliaro, Chair Donald C. Loughry, Vice CluJirAndrew G. Salem, Secreta.ry

Deunt. Bod.tollPllul L. BorriUClyde CampJ."",. M. DalyDonllid C. FlcckenlltcinJ.y FOTlter·Dllvid F. FrankllnIngrid Fromm

·Member Emeritus

Tbomn L. HllnnanDonald N.lIeinnl../lKeOllet.h D. HelldrixJohn W.Hon:hBen C.JohnaonIvor N. KnightJOlleph Kooplillger·Irving KolodnyMich...,l A, t.wkr

John E. M.y, Jr.L.WTenc:e V. MoC.UT. DOllM\(h.el'Still' L, NilssonJohn L. R.nkineRonald a. ReimtorCll!')' S. Robln&OllTeITI../lOO R. Whilt<!""""

Also included were the following nonvoting IEEE Standards Board liaisons:

FeruandoAldllnaSatiolh K. AllKarwal

J."",.BeIlURiehud B. Engelman

Sl.llnley W.....h.w

Mary LyonI' Niel..,..tltEE SIDnd=-<h Ihp<>rlmc"l Project Edilcr

by I"C INSTITUTE 0, ELECI~ICAl 3 ElECTRONICS ENGINEERS {IEEE)1 22,S<> 04 lqq"

IEEE C57.10Q 9\ .. 4605702 0504357 532 ..

Contents

SECI10N PAGE1. Introduction 9

1.1 Scope 91.2 Limitations 91.3 References 10

2. General Theory 102.1 Cellulosic Decomposition 112.2 Oil Decomposition IL2.3 Application to Equipment lL2.4 Establishing Baseline Data 122.5 Recol:flition ofa Gassing Problem-Establishing Operating Priorities 12

3. Interpretation of Gas Analysis 133.1 'I'hennal Faults 133.2 Electrical Faults--Low Intensity Discharges 133.3 Electrical Fault.s--Iligb Intensity Al'eing 13

4. S~gcst.edOperating Procedure. Utilizing the Detection and Anal)'sil ofCombustible Gases 134.1 Det.e-rmining Combustible Gas Generating Ratel 144.2 Determining the Gas Space and Dissolved Gas·in-Oil Equivalents 154.3 Monitoring Insulation Deterioration Using Di5Solved Gas Volume 164.4 Evaluation ofTransfonner Condition Using Individual and TeG

Concentrations 174.4.1 Determining the Transformer Condition and Operating Procedure

Utilizing TeG in the Gas Space 194.4.2 Determining the Operating Procedure and Sampling Intervall"rom

the TOCG Levels and Generating Rates in the Oil 194.5 Evaluation of Poasible Fault 'I)-pe by the Key au Method 20-4.6 Evalualion of Possible Faull 'tYpe by Analysis of the Separate Combustible

Gases Generated 224.6.1 Evaluation of Possible Fault Type by the Doernenburg Ratio Method 224.6.2 Evaluation ofPouible Fault Type by the RlJiers Ratio Method 23

5. Inslruments for Deted.ing and Determining lheAmounl of Combustible GasesPresenl 245.1 Portable Instruments 245.2 Fixed Instrumenls 25

5.2.1 tlelhod 1 255.2.2 Melhod 2 265.2.3 tfelhod 3 26

6. Procedures fOT Obtaining Samples of Gas and Oil From the Ttansfonner forLaboratory Analysis 276.1 Gas Samples for Laboratory Analysis 276.2 Gas Dissolved in Oil 27

7. Laboratory Methods fOT Analyzing the Gss Blankel and the Gases Extracted Fromthe Oil 277.1 Detennination ofTolal Dissolved Gas 277.2 Detennination of Individual Dissolved Gases 27

by the INSHTUTE CIF El£CIRICAl & ELECfRaHCS EHGlIlEERS IIEEE)I 22.J/io.Q-t 1991>

IEEE C57.104 91 .. 4605702 0504355 479 ..

7.3 Determination of lndividual Gases Present in the Gas Blanket 27

8. Bibliography 288.1 Sources 288.2 Gas Evolution 288.3 Detection and Interpretation.......................................... . 30

8.3.1 Gas Detect.<Jr Relay 308.3.2 Gas Cushion in Sealed Transformers 318.3.3 Dissolved Gas in Transformer Oil 34

FIGURES

Fig 1 Halstead's Thermal Equilibrium Partial Pressures as a Function ofTemperature 12

Fig 2 Operating Procedure F10w Chart 15Fig 3 Key Gases Evaluation 21Fig" Doemenburg Ratio Method F10w Chart 24Fig 5 Rogers Ratio Method Flow Chart 25

TABLES

Table 1 Dissolved Gas Concentrations 18Table 2 Actions Based on TCG 19Table 3 Actions Based on TDCG 20Table" Concentrations afDissolved Gas 23Table 5 Ratios for Key Gases-Doernenburg 23Table 6 Rogers Ratios far Key Gases 26

7

"19h~ by tho INSIITUIE OF ELECTRICAl & ElECIRON,CS ENGINEHiS IIEEE)Sop 01 22,31>,04 1'196

IEEE C57.~04 91 .. 4805702 0504359 305 ..

IEEE Guide for the Interpretation of GasesGenerated in Oil-Immersed Transformers

1. Introduction

The detection of certain gases generated in an oil-filled transformer in servi.ce is frequentlythe first available indicati~n of a malfunction that may eventually lead to failure if not cor­rec:ted. Arcing, corona disc:harge, low-energy sparking, severe overloading, pump motor faH­ure, and overheating in the insulation system are some of the possible mechanisms. Thesec:onditions oc:curring singly, or as several simultaneous events, can result in decomposition ofthe insulating materials and the formation of various combustible and noncombustible gases.Normal operation will also result in the formation of some gases. In fact, it is possible for sometransformers to operate throughout their useful life with substantial quantities of combusti­ble gllses prescnt. Operating a transformer with large quantities of c:ombustible gas present isnot a normal occurrence but it does happen, usually after some degree of investigation and anevaluation of the possible risk.

In a transformer, generated gases can be found dissolved in the insulating oil, in the gasblanket above the oil, or in gas c:olleding devices. The detection of an abnormal c:onditionrequires an evaluation of the amount of generated gas present and the c:ontinuing rate ofgen­eration. Some indication of the soun::e of the gases and the kind of insulation involved may begained by determining the composition of the generated gases.

1.1 Scope. This guide applies to minernl-oil-immersed transformers and addresses:

(1) The theory of combustible gas generation in a transformer(2) The interpretation of gas analysis(3) Suggested operating procedures(4) Various diagnostic techniques, such as key gases, Dornenberg ratios, and Rogen ratios(5) Instruments for detecting and determining the amount of combustible gases present(6) A bibliography of related literature

1.2 LiDlit.ations. Many techniques for the detection and the measurement of gases have beenestablished. However, it must be recognil:ed that analysis of these gases and interpretation oftheir significance is at this time not a science, but an art subject to vwiability. Their presenceand quantity are dependent on equipment variables such as type, location, and temperatureof the fault; solubility and degree of saturation of various gases in oil; the type of oil preserva­tion system; the type and rate of oil circ:ulation; the kinds ofrnaterial in contact with the fault;and finally, variables associated with the s.ampling and measuring procedures themselves.Because of the variability of acceptable gas limits and the significance of various gases andgeneration rates. a consensus is difficult to obtain. The principal obstacle in the developmentof fault interpretation 8S an exact scienc:e is the lack of positive cOTTelation ofthe fault·identi·fying gases ",';th faults found in actual transformers.

The result of various ASTM testing round robins indicates that the analytical proceduresfor gus analysis are difficult, have poor precision, and can be wildly inaccurate, especiallybetween laboratories. A replicate analysis confirming a diagnosis should be made before tak·ing any major action.

9

. bX t.toe INSTITUTE Of ElECTRICAL to ELECTRONlCS EN<lINEFIlS (IEEE))! 22,36,04 1996

IEEE (57.104 91" 4605702 0504360 027 ..

U:EI:Std C67.104·1991 IEEE GUIDE FOR THE INrERPRETATION OF GASES

This guide is, in general, an advisory document. It provides guidance on specific methodsand procedlue!> to Assist the tranf;former operator in deciding on the status and continuedoperation of a transformer that exhibits combustible gas formation. However, operators mustbe cautioned that, although the physical reasClnS for gas formation have.ll. finn technical basis,interpretation of that data in tenns of the specific cause or causes is not an exact science, butis the result of empirical evidence from whieh rules for interpretution have been derived.Hence, u:aet causes or conditions within transfonners may not be inferred from the variousprocedures. The continued application of the rules and limits in this guide. accompanied byactual confirmation of the causes of gas fonnation, will result in continued refinement andimprovement in the correlation of the rules and limits for interpretation.

Individual experience with this guide will assist the operators in determining the best pro­cedure, or combination of procedures, for each specific case. Some of the factors involved in thedecision of the operator are: the type of oil preservation system, the type and frequency ofthesampling program, and the analytical facilities available. However. whether used separatelyor as Ci:lmplements to one another, the procedures disclosed in this guide all provide the oper­ator with positive and useful information concerning the serviceability of the equipment.

1.3 Referencel. The following references lIhould be used in conjunction with this guide:

[1] ASTM D2945.90. Test Methods for Gas Content of Insulating Oils.)

[2] ASTM D3305-84 (Reaff. 89), Method for Sampling Gas (rom a Transformer.

[3] ASTM D3612·90, Test Methods for Analysis of Gases Dissolved in Electrical Insulating Oilby Gas Chromatography.

[4] ASTM D3613·87, Methods for Sampling Electrical Insulating Oils (or Gas Analysis andDetermination of Water Content.

1.4 Definitions. The follov.ing definitions of terms are used in this guide:

key galel. Gases generated in oil-filled transfonners that can be used for qualitative deter­mination of fault types, based on which gases are typieal or predominant at varioustemperatures.

partial discharce. An electric discharge that only partially bridges the insulation betweenconductors, and that mayor may not occur adjacent to the conductor.

TCG. Total combustible gas.

TOCG. Total dissolved Ci:lmbustible gas.

2. General Theory

The two principal causes of gas formation within an operating transformer are thermal andelectrical disturbances. Conductor losses due to loading produce gases from thermal decompo­sition of the associated oil and solid insulation. Gases 8re also produced from the decomposi­tion of oil and insulation exposed to arc temperatures. ~nerally, where decomposition gasesare formed principally by ionic bombardment, there is little or no heat associated with low·energy dischar&:es and corona.

'ASTM publi<:.lious ....veilebl.. from the eu.tom.... Service Department, American Socie~y for Telting Iud MetAl·riel", 1916 R..<:r. St",et. Philedelphl•• f'A 19103, USA.

10

"19M by ,ho INSTITUT£ OF ElECTRICAl 8. ELECTRONICS ENGINEERS (IEEE)Sop 01 22,3b,O<l 199"

IEEE (57.104 91" 4805702 OS043b1 Tb3 ..

GENERATED m OIL-IMMERSED TRANSFORMERSIEEE

Std C57.104-1991

2_1 Cellulosic Decomposition. The thermal decomposition of oil-impregnated celluloseinsulation produces carbon oxides (CO, COiJ and some hydrogen or methane (Hz, CH4) due tothe oil (C02 is not a combustible gas). The rate at which they are produced depends exponen­tially on the temperature and directly on the volwne of material at that temperature. Becauseof the volume effect, a large. heated volume of insulation at moderate temperature will pro­duce the same quantity of gas as a smaller volume at a higher temperature.

2.2 Oil Decoxnpo.tition. Mineral transformer oils are mixtures of many different hydrocar­bon molecules, and the decompositicm processes for these hydrocarbons in thermal or electri­cal faults are complex. The fundamental steps are the breaking of carbon-hydrogen andcarbon·carbon bonds. Active hydrogen atoms and hydrocarbon fragments are formed. Thesefree radicals can combine with each other to form gases, molecular hydrogen, methane,ethane, etc., or can recombine to form new, condensable molecules. Further decomposition andrearrangement processes lead to the formation of products such as ethylene and acetyleneand, in the extreme, to modestly hydrogenated carbon in particulate form. These processesare dependent on the presence of individual hydrocarbons, on the distribution of energy andtemperature in the neighborhood of the fault, and on the time during which the oil is ther­mally or electrically strcsscd. These reactions occur stoichiometrically; therefore, the specificdegradations of the transformer oil hydrocarbon ensembles and the fault conditions cannot bepredicted reliably from chemical kinetic considerations. An alternative approach is to assumethat all hydrocarbons in the oil are decomposed into the same products and that each productis in equilibrium with all the others. Thermodynamic models permit calculation ofthe partialpressure of each gaseous product as a function oftemper8.lure, using known cquilibrium con­stants for the relevant decomposition reactions. An example of the results of this approach isshown in Fig 1 due to Halstead. The quantity of hydrogen formed is relatively high and insen­sitive to temperature; formation of acetylene becomes appreciable only at temperatures near­ing 1000 °C. Fonnation of methane, ethane. Bnd ethylene each also have unique dependenceson temperature in the model. The thermodynamic approach has limits; it must assume anidealized but nonexistent isothermal equilibrium in the region of a fault, and there is no pro­vision for dealing with multiple faults in a transformer. However, the concentrations of theindividual gases actually found in a transformer enn be ul>ed directly or in ratios to estimatethe thermal history of the oil in the transformer from a model and to adduce any past orpotential faults on the unit. As the simplest example: the presence of acetylene suggests ahigh temperature fault, perhaps an arc, has occurred in the oil in a transformer; the presenceof methane suggests th at-if a fault has occurred-it is a lower energy electrical or thermalfault. Much work has been done to correlate predictions from thermodynamic models withactual behavior of transformers.

2.3 Application to Equipment. All transformers generate gases to some extent at normaloperating temperaturu. But occasionally a gas-generating abnormality does occur within nnoperating transformer such as a local or genenl overheating, dielectric problems, or n combi­nation of these. In electrical equipment, these abnormalities are called ~faults." Thermal,corana, and areing faults are described in 3.1, 3.2, and 3.3. Internal faults in oil produce thegaseous byproducts hydrogen (H2), methane (CH4 ), acetylene (CZH2), ethylene (CZH4 ), andethane (CzHs). 'When cellulose is involved, the faults produce methane (CH4), hydrogen (Hz),carbon monoxide (CO), and carbon dioxide (C02), Each of these types offaults produce certaingases that nre generally combustible. The total of all combustible gases may indicate theexistence of anyone, or a combination, of thermal. electrical, or corona faults. Certain combi­nations of each of the separate gases detennined by chromatography arc unique for differentfault temperatures. Also, the mtios of certain key gases have been found to suggest faulttypes. Interpretation by the individual gases can become difficult when there is more than onefault, or when one type of fault progresses to another type, such as an electrical problemdeveloping from a thermal one.

11

< b¥ <~" INSTllUTE OF ELECHHCAL & ELECTRONICS fUGJNEERS ((EEEl01 Z2,3~,0<l Iq9b

IEEESld C57.104-1991

IEEE (57.104 91 .. ~~05702 0504362 9TT ..

IEEE GUIDE FOR THE INTERPRETATION OF GASES

.3

.,

.,

·3

.,

,m 'C 1225~ 725 "CTEMPERATURE

C,H•

22$°C

Fir 1Halstead's Thermal Equilibrium

Partial Pressures as a Function of Temperature

Attempts to assign greater significance to gas measurements than justified by the naturalvariability of the generating and measuring events themselves will lead to gross errors ininterpretation. However, in spite of these limitations, these gas-generating mechanisms arethe only existing basis for the analytical rules and procedures developed in this guide. In fact,it is known that some transformers continue to operate for many yean in spite of above aver­age rotes of gas generation.

2.4 Establishing Baseline Data. Establishing a reference point for gas concentration in newor repaired trll.nsformers and following this with a routine monitoring program is a key ele­ment in the application of thig guide. Monitoring the health <scrviceobility) of a transformermust be done on a routine basis and can start anytime, not just for new units.

Generally, daily Dr weekly sampling is recommended nf'ter start-up, followed by monthly orlonger intervals. Routine sampling intervals may vary depending on application ond individ­ual system requirements. For example, some utilities sample generator step-up (GSU) trans­formers four to six times a year, units rated over 138 kV twice a year, and some 765 kV unitsare sampled monthly.

2.5 Recognition of a Gassini' Problem-Establishini" Operatinr Priorities. Muchinformation has been acquired over the past 20 years on diagnosing incipient fault conditionsin transformer systems. This information is of a general nature but is often applied to veT)'

12

7

'19M by t~~ WSTIIUTE OF ELECTRICAl & ELECT~ONICS EU(iHl(ERS II(EE)\.to 01 22,31>,04 1991>

GENERATED IN OIL·IMMERSED TRANSFORMERSIEEE

Std cti7J 04·1991

specific problems or situations. One consistent finding with all schemes for interpreting gasanalysis is that the more information available concerning the history of the transformer andtest data. the greater the probability for a correct diagnosis of the health of the unit.

A number of simple schemes employing principal gases or programs using ratios of keygases have been employed for providing a tentative diagnosis when previous information isunavailable or indicated no fault condition existed. Principal gas or ratio methods requiredetectable or minimum levels of gases to be presents or norms to be exceeded, before they canprovide a useful diagnosis.

3. Interpretation of Gas Analysis

3.1 Thermal Faults. Referring to Fig 1, the decomposition of mineral oil from 150°C to500 °C produces relatively large quantities of the low molecular weight gases, such as hydro­gen (H2) and methane (CH-l), and trace quantities of the higher molecular weight {:8ses ethyl­ene (C2H4) and ethane (C21"4). As the fault temperature in mineral oil increases to modesttemperatures, the hydrogen concentration exceeds that of methane, hut now the tempera­Lures ure accompanied by significant quantities of higher molecular weight gases, first ethaneand then ethylene. At the upper end of the thermal fault range, increasing quantities ofhydrogen und ethylene and traces of acetylene (C2H2) may be produced. In contrast with thethermal decomposition of oil. the thermal decomposition of cellulose and other solid insulationproduces carbon monoxide (CO), carbon dioxide (C02), and watervapOl' at temperatures muchlower than that for decomposition of oil and at raus exponentially proportional to the temper­ature. Because the paper begins to degrade at lower temperatures than the oil, its gaseousbyproductll 8re found at nonnal operating temperatures in the transformer. A GSU trans·former, for eltamplc, that operates at or near nameplate rating will normally ganeratl' severalhundred ports per million (ppm) of CO and several thousand parts per million of CO2 withoutexcessive hot spots.

The ratio ofC0:IC0 is sometimes used as an indicator of the thermal decomposition of cel­lulose. This ratio is normally more than seven. For the COiCO ratio, the respective values ofCO2 and CO sbould exceed 5000 ppm and 500 ppm in order to improve the certainty (octor,i.e., ratios are sensitive to minimum values. As the magnitude of CO increases, the ratio ofCOliCO decreases. This may indicate an uLnQrmality that is degrading cellulosic insulation.

3.2 Electrical Faults-Low Intensity Discharges. Referring to Fig 1, low intensity dis·charges such as partial discharges and very low level intermittent arcing produce mainlyhydrogen, with decreasing quantities Q( methane and trace quantities of acetylene. As theintensity of the discharge increases, the acetylene and ethylene coneentrations rise signifi.cantly (see Tnble 6).

3.3 Electrical Faults-High Intensity Arcing. Referring to Fig 1, as the intensity of theelectrical discharge reaches arcing or contjnuing discharge proportions that produce tempera­tures from 700 °C W 1800 °C, the quantity ofocetylene becomes pronounced.

4. Suggested Operating Procedures Utilizing the Detection andAnalysis of Combustible Gases

FrQm an op.erational point of view, it is important to establish the following priQrities;

(1) Detection. Detect the generation of any gases that exceed ~nonnal" quantities and uti~

lile appropriate guidelines so the possible abnormality may be recogniled at the carli·est possible time in order to minimize damage or avoid a failure.

13

,by the lNSTlTUl( OF HEtTI/leAL & ElECTRCl'IlCS ENGH~EE~S (IEEE Il\ 22,J6,O~ 1996

IEEEStd C57.104_1991

IEEE (57.104 9~ .. 4605702 0504364 772 ..

IEEE CUIDE FOR THE INTERPRETATION OF CASF.8

(2) Evaluation. Evaluate the impact of an obnonnality on the serviceability of the trans·former. using II l>ct of guidelines or recommendations.

(3) Action. Take the recommended action, beginning with increased surveillance and con­firming or supplementary analysis and leading to either a detennination of load sensi·tivity. reducing the load on the transformer, or actually removing the unit from service.

The success of fault gas analysis necessitates the earliest possible detection of gases usingthe following methods:

Direct measurement of the amount of combustible gas in the gas space or relay ['IbtnlCombustible Gas (TCO)-See 5.2.1 and 5.2.2].

Direct measurement of the amount of combustible gas dissolved in the oil (gas-in-oilmonitor~ee5.2).

Chromatographic separation and analysis for the individual components in a gas mix­ture extracted from a sample of the transformer oil or a sample of the transfonner gasspace (See Section 7).

An opernting procedure utilizing the gas data from the above sources is to be developedimmediately following the initial detection of combustible gases. Fig 2 is a flow chart thattraces the suggested process from the initial detection of combustible gas to the final assess·ment of the status of the transformer.

4.1 Determmine Combustible Gas GeneratiDe Rates. A given gas volume and distribu­tion may be generated over a long time perioo. by a relatively insignificant fault or in 11 veryshort time period by a more severe fault. Hence, one meaiurement does not indicate the rateof generation and may indicate very little about the severity of the fault. Once a suspiciousgas presence is detected, it is important to be certain whether the fault that generated the gasis active.

An evolution rate greater than (0.1) ft3 ofCQmbustible gas per day may indicate the unit hasan aelive internal fault. To calculate the rate of evolution, take the sum of the concentrations(in ppm) of all the combustible (everything but CO2, O2• Nv in the first and second samplesand use Eq 1.

R=(ST-SO) xVxlO-(l

7.5 x 7'

(Eq 1)

where:

R ::: Rate (fl.3/day)So = First sample (ppm)

ST = Second sample (ppm)

V = Tank oil volume (gallons)T = Time (days)

Limits for average gas generation rates are given for gas space analysis (TCG) in -4.4.1, andfor total dissolved gas analysis rrnCGl in 4.4.2.

14

'l~M by the IN$T!1UTE OF ELECTRICAL & ELECH~ONICS ENGINEERS (IEEE)~p 01 22,36,04 199t>

IEEE (57.104 9~ .. ~805702 050~365 609 ..

IEEEGENERATED IN OIL-IMMERSED TRANSFORMERS Std C67.104.1991

GAS DETECTED INRelAY, GAS SPACE.OR OOl

cor"'ARE VALUESWITH TABLE 1

TABLE 1 INDICATES TABLE 1 IHOICATES

CONOmON I: OOHOITIOfIlS 2, 3,.:NORMAL PROBLEM MAY EXIST

RESUME NORMAl RESAMPLE: TO FINDSURVEILLANCE GENERATING RATE:

REFER TO •. I

IGAS SPACE OR DISSOLVED IN OIL:RELAY SAMPLE: GO TO TA8t.E 3GO TO TABlE 2

T IINVESTIGATE POSSIBLE FAULT TYPE USINGMETHODS DESCRIBED IN •.5.1 ••.&.1. ot ••6.2. REO-Qt.1MENOED INrTIAl RESAA4PUNG INTERVAL ANDOPERATING PROCEDURE.

I

ADJUST SAMPLING INTERVALAND OPERATINGPROCEDURE BASED ON ACCUMUlATeD DATAAND EXPERIENCE

EXAMPlESCONSERVATOR GAS SPACE

STEP ,: GAS DETECTED IN GAS DETECTED INOIL GAS SPAce

STEP 2: DATA (PPM): Ht. TOTAL GAS. 1.S-,r.270. cu. w 1110, CO.280. CA .31. (7H.wI1.CIf. ••TOTAL DISSOlVEDCOM8USTI8LE GAS{TOCG).1liIS

STEP 3: TABLE 1 INDICATES PAOCEEDTOCONDrTlON 2 STEP.

STEP .: RESAMPLe (SEE RESAMPLE (SEE'.1) INDICATES A ••1) INDICATES ARATE OF 20 PPM! RATE OF .025'l\JDAY AND INCREAS- OAYAND

'"0 INCREASING

STEP 5: TABLE:) TABLE 2

INDICATES CONDITION 2, INTERVAL CAND PROCEDURE 3. AO..,..,SE MANUFAC­TURER; EXTREME CAUTION: PlAN OUT­AGE: RESAMPLE PER INTERVAl;ANALYlE GAS SPACE AND DISSOLVEDGAS COMPONENTS [SEE NOTE (I)J

STEP 15: ••5 KEY GAS: H;l> CH.&-ELECTRlCAL.COR""'-•.6.1 OOERNENBURG (seE Nore (')JFAULT TYPE: POSSlBLEARCING••.6.2 ROGERS: FAlA.TTYPE: CASE 2POSSiBlE ARCING.

NOTES: (1) A.ume equal diuol..od mmponeata in both Q.l.lDplea.(2) Ad.ual c... "'u in.pec:l.cd when CaRl ,.,..,hed.O ppm. FouDcI arcin, belw...n inaul.ted NLTC ,ball.pin aod <:wpl.iD,fof drive mncba..MIln..

Fie 2Opcrntine Procedure Flow Chart

4.2 Dctcnnininr the Gal" Space aDd Di.uolved Gas-in·Oil Equivalents. Gas space andoil equivalents are used to compare the results of analysis of the gas space (TeG) with TesultsfTl,lm analysis of the gases dissolved in the oil (TDCG). Comparisons of gas Talios obtainedfTom the gns space can then be compared to similar Tatios of gases extraeted fTom the oil. Itshould be nOl.e<! that the calculated equivalent values ofTeG, and experimentally measuTedvslues of TCG pTobably do not show close agreement., since the equation fOT obtainin&, theequivslents assumes the existence of equilibrium between the gas blanket and the oil. Thiscondition may not exist., particularly in the case of an actively progressing fault. However, theequation is valuable for the determination of a limiting value for the expected total ~mbusti·

15

_ by VI. INST I1UT[ OF ElEClIlleAl & E"EcTRCI-lICS ENGlIlEERS I [EEE)II 2:2,36'(),l l'''l>

IEEEStd C51.lGfo-I991

IEEE C57.10~ 91 .. ~605702 050~3bb 5~5 ..

IEEE GUIDE FOR THE n-.'"I"ERPRETATION OF CASES

ble gas concent.ration in the gas blanket. The dissolved gas equivalentoflhe TCG. is obtainedusing the following equation:

(Eq 2)

where:

rcGe '" An estimate of the percent ofcomoostible gas in the gas spaceC :: Combustible gasG .. Each gas dissolved in oil (combustible and nonc;ombu.stible)Fe :: The concentration expressed in parts per million (ppm) of combustible gas g

dissolved in oilBe :: The Ostwald .olubitity coefficient of combust.ible gasgF. :: The coneetration ofa particular gas dissolved in oilBit ,. The Ostwald solubility coefficient of particular EllS

G.. OILw&ld Coefficient (8)(26°Cl

R,' 0.0429

0, '""co, ..,00

""'" OJ"

c,H,' ",N, 0.0145

CO' 0.102

c,R,' .."C~.o 0.331

°CDmlnlltiblel

Note: Owr.",.ld .....ffici""tl an for LII. oil ....ith • delllilyof 0.880•• ""mpt'r.u,11"e of 26 "'C, .lId • p.........,.. or 1IlmoIph"'....

4.3 Mouitorin, losulation DeteriomtioD VsinK Dissolved Ga. Volume. ODe acceptablemethod for monitoring the deterioration of transfonner insulating material involves calculat­ing tha tolal volume of gas evolved. The total volume of evolved gas is an indicator of the mag­nitude of incipient faults. Succeeding samples indicate dlange' with time as the fault{s)develop. Trends are readily apparent. when gas volume is plotted versus time.

1b determine the volume. in gallons, offault gas dissolved in insuiliting oil, use Eq 3.

16

lh. by u... mSlITUf( OF' EUCf"tCAl .. £UCTI?OHICS (t'GINE£1<S U(((I, Of 22,)6,001 1_

IEEE (57.104 91. 4805702 0504367 liB.

CENERATED IN OIL-IMMERSED TnA.~SFOnMEnSIEEE

Std C67.104.1991

FG(V)

1,000.000

<&I 3)

where:

FG '" Sum of H2. Cf-4. CtH,. C2H4, G,:H2' and CO (ppm)V '" Volume of oil in transformer (gallons)TCG" '" 1Ot81 disfOOlved combustible eas (gallons)

This straightforward method is useful for completely oil·filled (etlnservator-type) transform­ers with eanditions that produce r;mall quantities of fault cas. These conditions warrant eon·tinued monitoring but ),ave not yet developed a distinct character aecording to the othermethods of fnult delemlinHtion described in this guide. This fnulL-gns volume method eontin·ues to be useful as fault conditions enlarge, with the added advantage that it permits continu­ous monitoring of insulation deterioration in spite of any oil handling activity that includesdegassification.

4.4 Evahw.tion of Transformer Condition Using Individual and TDCG Concentra·tions. It enll be difficult to determine whether a trallsformer is behaving normally if it has noprevious dissolved gas h istoT)'. AIS(), considerable difTerem:es of opinion exist for what is con·sidered a "normal transformer" wilh acceptable concentrations of gases.

A four-level criterion has been developed to classify risks to transformers. when there is noprevious dissolved gas histoT)'. for continued operation at various combustible gas levels. Thecriterion use' both concentration, for separate gases and the total concentration of all com­bustible gases. See Table 1.

Condition 1

Condition 2

Condition 3

Condition 4

TDCG below this level indicates the transformer ill operating satisfactorily(see Fig 2). Any individual combustible gas eJt:ceeding specified levels shouldprompt additional investigation (see 4.5 Bnd 4.6).

TDca within this range indicates greater than normal combustible gas level.Any individU!l1 combustible gas uceeding specified levels should prompt addi­tional investigation. Proceed per l-lg 2, Step 3. Action should be taken toestablish a trend (Fig 2. SteP 4). FaulUs) may be present. Proceed to 4.4.1 or4.4.2.

TDCG within this range indicates II high level of decompo6ition. Any individ­ual combustible gas eJt:ceeding specified levels should prompt addition31 inves­tigation. Pnceed per Fig 2, Step 3. Immediate action should be L'lken westablish a trend (Fig 2, Step 4). Fault(s) ure prob3hly present. Proceed to4.4.lor4.<l.2.

TDCG within this runge indicatcs cJt:cessive decomposition. Continued opera­tion could result in failure of the transformer. Proceed immediately and withcaution per Fig 2, Step 3, and 1.4.1 or 1.4.2.

Table 1 lists the dissolved gas concentrations (or the individual gases lmd TDCG for Condi­tions 1 through 4. This Loble is used to make thc original assessment ofa i:assing condition onII new or recently repaired transformer or is used if there are no previous tests on the trans·former for dissolved gases or if there is no recent history. Users of this guide are advised thatthe dissolved gas concentrations contained in Table 1 are consenSuS values based on the expe­riences of mnny companies. The transformer operator may de·tide to use different dissolved

17

I t"~ WSllIVIE 0# HECII>IC"'L l ELECTROIlICS Ef.IGWEERS (IEEE)22,30,04 l"~~

rEEEStd C57.lC)4·l\H/l

IEEE (57,104 91" 4605702 OS043b8 318 ..

IEEE GUIDE FOR THE INTERPRETATION OF GASES

gas concentrations for the individual gases (particularly acetylene) and TDCG ba~ed on enl,ol­neering judgment. and experience with other similar t.ransformers.

Tnblc 1Dissolved Gas Concentrations

Diuolved Key Gu ConO>entnotwll limit. (ppw·)

St"tUIII, ell, C,H, C214 C:t'Ii co co, TDCGO.

Cnndition 1 '" 120 " '0 " 350 ''''' no

Cnndition 2 101_700 121-400 36-60 fil-IOO 66-100 351--li70 ,,""- 721_

.000 ,,,.Condition 3 101- 401_ ,,-"" 1 OJ -200 101-150 571_ 4001_ 192.1-

'800 '000 1<00 '0000 "'"Conditinn 4 >1800 >1000 "" ,200 "'0 >1400 ooסס" ,"'"NOTES, (1) Tlbl" 1 ..Ium.... thlt liD previOUI ....It. on the tnon.form..e foe diloolve<l pi anal)"I;' hive """nWIld... DC th"t n" receot hiltOl'Y exiotl. If" p.....mUI Inalyeis nilto, it Ihcluld be reviewed to dc....rm.in.. if til".itu"li"n i••t.bl.. oe unot.bl... Ror~r to Table. 2 and 3 for IpprcprilU, ldion(o) tb be tlkon.(2) An ASTM round robiD Wdiclt.ed vlnlbility in g... ",,"Iy.i. between I,bl. Thil .hould be <XIlllideM wh... nIllving ga. analy"i, WIlde by dirr"",nt lib"o Th... numbere .h<lwn in Tablet .re in parte org.. pee tnillion parte o( oil (ppm) volum..tricl.!ly and ..no b....<t

on .. llrge powoe tr..,,"former Wilh ....""ml tboulllnd go,lIo,," ofoU. Wilh 1 ImAller on volume, th" um.. volumeor gal wiU giv" • highee 1l.A.:>.....e"t....tion. SIJl,IU dillributio" tran.rormere .,,01 vollage regul ..tore rn.y oe>D­tai" combu8tibl.. gu.... bccflU8C ortlle operotion or internal expul.ion £U ....I oe load brelk .witch..... The .tatUI<Dd.,. in T..bl" 1 are .110 not .pplic.ble to other ,pPlU"ltlll ira which 101<1 brn.lr. Iwitch.... openou, u"der oll ... The TDCG VAlue dOClI "ot wclud.. CO~. which;1 DOL ... combu.tibl"gll.

The condition for a particular transfonneT is detennined by finding the highest level faTindividual gases or the TDCG in Table 1. For e:umple, if a sample contained the following gasconcentration!J (in ppm, voVvo1):

the gases that. fall into the highest. condition are H2, CH4•CzHz, CzHa, and TDCG. Therefore,this data would indicate that the transfonner would be classified as Condition 2. This exam­ple cnn also be used to show two other facwrs that should be considered when using this table,that is, the age of the transformer and the type of incipient condition.

New transformers (a year or less) usually contain levels of gases that would fall well belo.....Condition 1 and do not contain delectable levels of acetylene. Theeefore, the dcg-ree of concernin the example would be much higher for a one-month-old transformer than a 20-year-oldtransformer.

Another consideration is that acetylene may be genemled from thr~ different incipientfault conditions, i.e., high temperature overheating of oil, partial discharge (Jow energy dis­charge), oe arcing. In the case of overheating, acetylene will represent a small proportion ofthe hydrocnrbon gnses. In the case of partial discharge, very high concentrations of hydrogenwill be generated relative to acetylene, and this would generally be a cause for concern eventhough the TOea is not abnonnal1y high. The most severe condition is arcing. When high­energy arcing OCCUT5, hydrogen and acetylene are generally of the same magnitude, liS ure thehydrocarbon gases. When an active arcing condit"ion is found, immediate attention isrequired.

18

9ht to; 'r,~ IIlS1ITU1E riO EllCTR\CAl.<: ELEC1FOtlltS ETfGWE'EF~ 11HE)001 22,36,04 lQQ6

IEEE C57.10Q 91 .. ~S0570C 050~3b9 254 ..

GEf'ERATED rN OIL-IMMERS£D 'J'Jl.o\N'SFORMERS

......1 DctcrmiDiDi' the Tr'8.ulformer Condition and Operatini' Procedure UtiliziogTCG in the Gal Space. When sudden inuea5es in the combustible gas concentrations orgenerating rates in the gas space of successfully operating transformers occur and an internalfault is suspected, use the proceduTt recommended in Fig 2.

TlI.ble 2 indicates the recommended initial $ampling intervals and operating procedures forvarious levels ofTCG (in percent).

Once the source of gassing is determined by analysis. inspection. consultation, or combina.tions thereof and the risk hilS been assessed, then enb';neering judgment should be applied todetermine the final sampling intcrvllJ Ilnd operating procedure.

Table 2Actions Based on TCe

So.m;>li.., Interv..l.. &lidO~..ti"'ll rr-du.-for e... CeDeTatioln R..tft

TCO TCO...... Row SampliAe ot-"..tilllll: Prooeduttell'"I (....do,.) Inl.er...J

Conditi.... > •• >.03 D..lly ConMder re......al r""n Mmoe.Advi_ m....urarturer.

.0:hOl Da.iI,.

<.ot Weeki,. £:oercise atrcrDe uuoo...A"ol~ for individual gflleo.Pian outo~.

Advt.e rnanuracturer.

Condition 3 <5 to,. .. 2 ,..03 Weekly E:oerdu C<tn!mol! cautio...Analy... for individual I."'•.

.0hOt Weekly PIon o"IIlK".

Monthl,.Adviae ......nufa.rt'''·fl·.

<.01

Coedit..... 2 <210,. ...5 :>.03 1.1lInlhly Ellc!"cise eo.utl....

Monlh.lyAnalyze r"r Individual ,0_.

.03...0t Do:urmi_ load. dot~n<kDCI:.

<.01"'~'"

Condl!Jofo I d >.03 Monthly E~rriaecautic>a......al,.u ror ind'vidual,.-.Det.rmio- load .peD......

.03-.01 Quarterl)' Continuo nonnal D~rotll>C1.

<.01 Annual

E:romple: A transfonner hI'S a TCa level of 0.•% and is generating gas at a constant rate of0.035% TCG per day. The table indicates Condition 2. It should be sampled monthly, and theoperator should follow Procedure 2 in Table 2.

".4.2 Detcrminini' the OpcmtiDC' Procedure and Samplinr Interval From theTDCG Leveb and Generalinr Rates in the Oil. When sudden increases in the dissolvedgas conLent of the oil in successfully optratine- transformers occur and an internal fault is sus­pected. the procedures N:commended in Fig 2 should be used. Table 3 indicates the recom·mended initial aampling intervals and operating procedures for vnrious levels of TDCe (inppm). An increasing gas generation rate indicates a problem of increasing severity; therefore,II shorter urnpling interval is recommended.

19

. ~, ~n. H1S1'lTVTE ~ £1£C'~Il;Al,. J E~ECTs:or<lCS Efo,]t1npS I~EEI

>l "l,~I>,04 1""'0

U:EEStd CIi7.104-1991

IEEE (57.104 9~ .. 4605702 0504370 T76 ..

IEEE CUIDE FOR TIlE INTERPRETAnON OF' GASES

Once the source of of gassing is determined by analysis, inspection, consultation, or combi­nations thereof and the risk, has been assessed, then eng'ineeringjudb,rment should be appliedto cietennine the final sampling interval and operating procedure.

Table gActions Based on meG

Sampling low""al. lod Operlting Pr<:>e(!dl,lru{or Gn ~n"ratiol'lRAtei

TOCC TDCG....0. Ra\.e • Sampling(ppm) (ppm/doy) In\.olrval Operating Pl'OC'ldl,lru

Conditioo 4 >4630 >30 Dllily Conlider """",vIII (mill ..,rvi.,.,.Adv..... m••lI,lf""tu....r.

' ....0 Daily

dO Wcckj)· Eu...,u" ntnom<' c.l,ltioll.Anll.1yze for individualgs..".PliO outage.Advig., manufacturer.

Condition 3 1921-4630 >30 Weekly E"",,";oe en.."ne caution.AnalYle fot individual gnci.

' ....0 Weekly Plan outage.Ad~mlllluracturer.

dO Monthly

Condition 2 721-1920 >30 Monthly I::""",i." ","ution.Anal)'le for individual ga.., •.

' ....0 Monthly Ik\.ermine load dependence.

dO Qul\l1etly

Condition I ~ 720 >30 :Mo.llthly Eu...,i.., caution.Anlllyze fot individualguc•.o..\.erminl load dotpeOdcnc1l.

llhlO QufU't.<!rly Continu.. nonnll ol"'ratim•.

dO Ao.nu.1

Er.ample: If 8. tTlillsformer has a TDCG level of 1300 ppm and generates gas at a constantrate below 10 ppm per day, it should be sampled quarterly, llnd the operator should follow Pro­cedure 2. If the rale increases to 30 ppm per day but remains constant, the operator shouldnow sample monthly.

4.5 Evaluation of Possible Fault Type by the Key Gas Method. The preceding discus­sion of the dependence on temperature of the types of oil and cellulose decomposition gases(2.1 and 2.2) provides the basis for the qualitative determination of fault types from the gasesthat are typical. or predominant, at various temperatures. These significant gases and propor­tions nre called Mkey gases." Fig 3 indicates thesp- "key gll.ses~ and relative proportions for thefour seneral fault types.

20

it,. by t"~ IIJ~T1TU1£ OF ElECf"-lCAl & ELEC1~OIJICS WGH'EE~S IIEEE)'01 ,,",3D 04 100..

IEEE (57.104 9~ .. 4805702 OS0437~ 902 ..

CENERATED IN OlL-IM:M£RSED TRANSFORMERSItt.

Sl.d C67.104.1991

I. Thermal==-Oil: Deeomposi- _tion prodUClS include ethylene !and methane, together with Qsmaller quaniries of hydrogen 3and ethane. Traces of acetylene f5may be fanned if the fault is ~

servcn~ or involves electrical ~

contracts. ::5Principal Gas - Ethylene li!

'00

'"..706Cso.,"20

", ,H,

Overheated Oil

"

Gas

"

C,H,

Ovcrhealed Cellulose2. Thermal--eellulose: Large lquantities of carbon dioxide 0'1

and carbon monoxide are Eevolved from overheated cellu- 2ilose. Hydrocarbon gases. such &;as methane and ethylene. will [be fonned if the fault involves ~

~

an oil·impregnated structure. dPrincipal Gas - Carbon Mon- II:

oxide

100 I 92

'"..'"6Cso.,"20

", L-'-Rr----;:,----=-c:o:--,,:o--r=--co I-It CH. c,ft. C,H. C~2

Gas

3. Electrical----CQ[Qoa: Low- !:energy electrical discharges III

produce hydrogen and rneth- Q~

ane, with small quanities of ~

ethane and ethylene. Campara- ~ble amounts of carbon monox- Q.

ide and dioxide may result ~from discharges in cellulose. dPrincip.al Ga.... _ Hydrogen a:

'00

'"..70

'"".,"20

",co H,

Corona in Oil

"

4. EleClI;cal Arcing: Large t.amounts of hydrogen and acet- til

ylene are prodUCed, with minor o§quantities of rneth.ane and eth· ...ylcoe. Carbon dioxide and car- ~

bon monoxide may also be Q.

fanned if the fault involves eel· ~lulosc. Oil may be carbonized. :s

wPrincipal Gas _ Acetylene II:

'00OJ

'"70soso.,"20

",co

60

s

CH.

Arcing in Oil

, 3

FirSKey Gasu Evaluation

21

~" tt~ II'SITTUIE Of ElECT~IC"'L 3. ElECTPf't'.:S E'~I1'£E'-:; 'IEEE}I ~,3l>, o.l 1''''''

IEEESld C57.104·1991

1[[[ (57.104 91" 4805702 0504372 849 ..

IEEE GUIDE FOR TIrE INTI::RPRETATfON OF GASES

4.6 Evaluation of P09sible Fault 'IYpe by Analysis of the Separate CombustibleGascs Gcncrated. The usc of gas ratios to indicate a single possible fault type is an empiri­ttll process based upon the experience of each individual investigator in correlating the gasanalyses of many units with the fault type subsequently assigned as the cause for disturbanceor failure when the unit was examined. This process was attributed to Doernenburg and sub­sequently confirmed by Rogers on European systems, from which the bulk of the diagnosticcorrelation is obtained. US investigators have applied the European rules to units on US sys­tems with varying degrees of success; however, a US data base ofeomparable si"l:e to !.he Euro­pean reports does not exist.

The diagnostic theories based upon the thermal degradation principles cie~cribed in 2.1 and2.2 employ an aITay of ratios of certain key combustible gases all the fault t.rpe indiC8tors.These five ratios are:

Ratio 1 (Rl) = CHiHzRatio 2 (R2) = C2HiC2H.Ratio 3 (RJ) = CzHiCH.Ratio 4 (R4) = C2Hs!C2H zRatio 5 (R5) = CZHJC2Hc

The nrst ratio method (Doernenburg; see 4.6.1) utilizes Ratios I, 2, 3, and 4. This procedurereQuirC8 significant levels of the gases to be present in order for the diagnosis to be valid.

The second method (Rogers; see 4.6.2) utilizes Ratios 1, 2, and 5. The ROl:"crs method doesnot depend on speeific gas concentrations to exist in the transformer for the diagnosis to beVAlid. However, it. suggests that the method be used only when the nonnallimits of the indiovidual gases have been Cltceeded.

4.6.1 Evaluation of Possible Fault 'IYpe by the Docrnenbure- RRtio Method. TheDoenlP.uburg method suggests the existence of three general fault types as discussed in Sec­tions 2 and 3. The method utilizes gas concentrations from which Ratios 1, 2, 3, and 4 are Cll,l·culat.ed. The step-by-step procedure (Row chort) is shown in Fig 4.

The values for these gases are first compared to special concentrations- I.I-Table 4 {seeSteps 2, 3, and 4 in Fig 4}--to oscertain whether there really is 8 problem with the unit andthen whether there is sufficient. generation of each gas for the ratio analysis to be applicable.Then the ratios in the order Ratio I, Ratio 2, Ratio 3, o.nd &ltio 4 arc compared to limitingvalues, providing II suggested fault diagnosis as given in Table 5. This table gives the limitingvalues for rntios of gases dissolved in the oil and gases obtained from the transformer gasspace or gus relay.

The flow chart in Fig 4 illustrates the step.by-step application of the Docmenburg ratiomethod for gases extracted from t}IC transformer oil only. Exactly the same procedure is fol­lowed for gases obtained from the gas space or gas relays, except the limiting values for theratios will be those appropriate for gas space (Table 5).

Descriptions of the steps indicated in Fig 4:

,

Step 1

Step 2

Step 3

Gas concentration~ore obtained by extrading the gases and separating themby chromatograph (see Section 7).

If at least one of the gas concentrations (in ppm) fOT H2, CH4, Cj!Hz, llnd ~H4exceeds twice the values for limit Ll (see Tnble 4) and one of the other threegases exceeds the values for limitLl, the unit is considered faulty; proceed toStep 3to determine validity of the ratio procedure.

Delennining validity of ratio procedure: If at. least. one of the gases in eachratio Rl, R2, ro, or R4 exceeds limit Ll, the ratio procedure is valid; other-

22

'1"" ty "H' 1I,STITl'IE Of FLEC;TF1CAl I:. HE~lPClncs EN()lIjEEI!~ ,IEEEI... 01 ~~,31>,O~ I09~

IEEE (57.104 91" 4&05702 0504373 785 ..

GENERATED IN OIL-IMMERSED TRANSFORMERS

Table 4Concentration or Dissolved Gas·

K..,.Cu eo.......' ...tio ... L1(ppm)

Hydro~.. (~) ""Mctk....e (CII.) 120

Carbon Monoxide (CO) 350

A.wtyle,..{C~H.,) "Etkylcne (C~l) 60

Eth..... (~~ ""'ThC'K Vlil...... dilTcr rJ'llftl Douncnbu"ll·.....d mindde'with Cocditloa 1 or TabJ,c 1 .

lEEEStd C67.1Q.4·1991

Step 4

Step 5

wise. the ratios are not significant. and the unit should be resampled andinvcstigutcd by alternate proc:cduru.

Assuming that the ratio analysis is valid, each successive ratio is compared tothe values obUlined from Table 5 in the order RI. R2, R3, and R4..

If all succeeding ratios for a specific fault type fall within the values given inTable 5, the suggested diagnosis is ....alid.

'Thble 5Ratios fOT Key Gase.-Doernenburr

Ratio 1 (Rl)CllJH,

EJrtrllCWd FJ'IlmOil Gu Space

Ratio '2 (R2)c,H,GH.

Extracl.ed FnxoOil Gu S,...,.,

Ratio 3 (ll3)c,HICH,

Extratt.ed FromOil Gu Space

Ratio 4 (R4)c,H.'C,H,

Ext..aetHF'romOil a.. Spaa!

1-Tbc1"Ol.&1 Decom·poaitioo

>1.0 >0.1. <0.76 <1.' <0.3 <0.1 >0.4 >0.'2

2-CaJ'llna (lnwInlenll(ty PO)

<0.1 <0.01 "'0.3 ",0.1 >0.4 >0.2

:i-Art-inl> (Hi~h

lnh.... ilyl-'J.»)>0.1d.O

>0.01<0.1

>0.715 >1.0 >0.1 ",0.4 <0.'2

4.6.2 Evaluation of Pouible Pault Type by the RogeN Ratio Method. The Rogersratio method follows the same general pro<:edure as the Doemenburg method, except ani)'three ratios (RI, R2, and RS) are used. This method, shown in the step-by-step flow chart (Fie5), is also based on the thermal degradation principles described in 2.1 and 2.2. Tbe validity ofthis method is based on correlation of the results of 8 much larger number offailure in ....estign.tions with the cas analysis for CIIch ease. But, as with we Doernenburg method, the Rol:ersratios can give ratios that do not fit into the diagnostic codes; therefure, other annlytieal meth·ods given in 4.4 and 4.5 should be considered, as well as other options oullined in Fig 2.

23

by v ... IUS'!TUI[ Of' [U"IiICAt- I; EUCTQ~:J.CS [UGltl[l"'S 1[[['..z,~.. ,o. ,,,,,'"

IEEE CS7.l04 91" 4805702 0504374 611 ..

IEEESld C67.1O.f-1991 IEEE CUrnE FOR THE INTERPRETATION OF CASJ,:S

PORN(CORONAl

F'AULT NOTIDENTIF'IABLE:RESAM;>LE

DISCHARGEARCINGFAULT NOTIDENTIFIABLE;RESAMPLE

THEAIJALFAULT

Fig 4Doernenbw;: Ratio Method Flow Chart

Tnble 6 gives the values for the three key gas ratios corresponding to suggested diagnoses(cases). Th'ese ratios, nccording to Rogers, llre applicable to both gases taken from the gasspaee (or relay) !lnd gases extracted from the oil. The fault types (cases) given in Tuhle 6 havebeen chosen by combining some cases from the number of fault types (lriginally suggested byRogers.

Fig 5 is a now chart describing the step-by-step application of the Rogers ratio meLhod.

5. Instruments for Detecting and Determining the Amount ofCombustible Gases Present

5.1 Portable Instruments. Many (If the gases generated by a possible malfunction in an oil­filled transformer arc combustible. The on-site detection and estimation of combustible gasesin the transformer in the field using a portable combustible gas meter can be the first and theeasiest indication of a possible malfunction, and it may form the basis for further testing or anoperating decision.

\Vhen II more accurate determination of the tolal amount of combustible gases or a quanti­tative determination of the individual componen.ts is desired, n laboratory analytical methodusing a gas chromatograph or mass spectrometer may be used.

Gases generated in transformers can be explosive. Strict precautions should be observedwhen sampling the gases from the transformer.

2'

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I£E£ (57.104 91 .. 4!05702 0504375 55~ ..

GJ::NERATED IN OIL-IMMERSED TR.Al"'SFORMERSIEEE

Std CIl1.llW.I991

INPUTGAS

C,II,,,--<,H.

,<. ,

N

y R,.1-1N

y CASE" 0NOFAU1..T

CAS<'LOW TEMPERA·lORETHERMALOVERLOADING

C,It,..-­C,II. R'"

y CASE 4.. THERMAL

<700 C

I

¢--s Y CASES,,3 THERMALN ,,700C

'"dN

yR'<. ,

y~-~-

CAse IPORAOK>INFLUENCEVOlTAGElRIV)

R'.1-1

yCAS< ,

Y HIGH--.. ENERGY

,,"'ING

Fig6Rogers Rutio Method Flow Chnrt

5.2 Fixed Instru.ments. The reliability oftTansformers can be improved by either monitor­ing the gas space or the gn5e$ dissolved in the oil using self-contained. fixed·mounted instru­ments. These eontinuous monitoring instruments indicate the presence of a certain gas or thetotal combustible gases as well as sound an warm when the combustible gases exceed a prede­termined level. Optional recorders can also be used to provide u duily record or Ole combusti­ble gllse5 pre5ent.

Jr the amount of the individual gas components is desired, a laboratory analytical methodusing a gas chromatograph or mass spectrometer should be used.

There ure three somewhnt rlllated methods or monitoring the gases, as de&cribed in the fol­lowing subsections.

N07E: Th..... .,..;U be a "".,.L.IX')' for the ratioe R2 aD<! R$ to ;lK........ tD a .atioabove 3 .. lhe clie<:l..."i& dlrvelo", in i""""aity

5.2.1 Method 1. The nr"t type of ga" monitor continually compores the thermal conductiv­ity of the trnnllformer gall with that or pure nitrogen and is suitable for any transformer of theclosed t)"J)e wiU1 a gas space llbove the transrormer oil.

It is calibrated v.;th hydrogen. although Ule proportions of the combustibles are notobtained from the measurements.

25

boy ~.... H.:.TtTUIE 01' [lh·~rCAl l Eterranc::; E'lGl'lEEl><; lIEHll 22,3<>,Q.l lOG"

IEEE (57.104 91 .. 4~05?02 050437b 494 ..

TF.F:E GUIDE FOR THE INTERPRF:TATION OF GASES

Table 6Rogers Ratios for Key Gases

'2 R> ROSuggetlWdFBultC_ 'ifj( CHi c.)~/

H, C~IIDiB!fnOolo;a

• <0.1 >0.1 <I.' Uni\ non..-ld.'

,'" <0.1 <1.0 I..,,,,,..:<ncrgy deMitylll"'Cing-PD(~

NOTE)

2 0.1- 0.1- >3.0 Amng---.}figb .....""·Ky,., .., di..,"ugc

,~" >0.1 1.' Low lCmpc"\urc

<1.0 ,., lh..no.J

, <0.1 >1.0 ..... TMI'lNoI <700·C

'", <0.1 >1.0 >3.0 'fhertt\Al >7oo·C

IEEESLdCS7.10~.1991

The transformer gas is continually circulaU!d through one section of a Wheatstone bridgeand returned to the trflnsformer. The other sedion of the bridge cOntains pure nitrogen and isbalnnccd ngninst the tTllnsformer gas.

\Vhen combustible gases are produced in the transformer, they mix with the tnmdhrmergas and increase the thermal conductivity of the transformer gas. The increase in the thermalconductivity of the trnnsformer gas unbalances the Wheatstone bridge, and the unbalance igproportional to the tolal of the combustible gases as indicated on a meter.

5.2.2 Method 2. The second type of gas monitor continuously samples the transformer gasat fixed intervals and bums any combustible gases present to provide a measure ofthe total ofthe combustible gases. This type ofmonil.or is used only on transformers with a positive pres·sure of nitrogen over the oil.

At a fixed interval (usually 24 h), a samplt! or the transformer gas is pumped from the unit,mixed with air, and passed over 8 platinum heating sensor of a Wheatstone bridge. Any com·bustible gas in the sumple is burned. This raises the temperature of the sensor alld unbul­ances the bridge, which was balanced against a second platinum sensor in air. The degree ofunbahmce is proportional to the amount of total combust.ible gas present in the transformergas as indicated on a meter.

5.2.3 Method 3. 'l'he third type orgas monitor continuously measures the amount of hydro.gen and other combustible gases dissolved in the transfonner oil.

Hydrogen and the other combustible gases of unknown proportions diffusing through a per­meable membrane will be oxidized on a platinum gfls-permellble electrode; oxygen from thea mbient air will be electrochemically reduced on a second electrode. The ionic contact betweenthe two electrodes is provided by a gelled high·concentration sulfuric acid electrolyte. Theelectric signal generated by this fuel cell is directly proportional to the total combustible gasconcentration and is sent to a conditioning electric circuit. 1'he resulting output signal is wm·perature compensated.

A relay is operated in conjunction with the percent. gus meter so that when the combustiblegases exceed a preset value the relay sounds an alarm.

26

i3h~ by the lNS1JIUTE:JF ElEC'RIC~L & ElEC1PClHCS EI1G!NEERS llEEEI~p 01 22,3b'0': 1"9b

IEEE (57.104 91 .. 460570Z 0504377 320 ..

CDo'ERATED IN OIL-IMMERSED 'IltANSFORMER5IEEE

Sl.d Cli7.164_1991

Alllll1it. lhat 4au~ soundfti an ClIClnn .hould lH! wmplul for complet~ 4rnJi)'si.s by ag~ chro­maUlgraph or m(1S$ Fipectromder.

At the time of installation and each year thereafter, the equipment should be 5tandardizedto be surc the monitor is operating properly. The operator !>hould follow the instruction guideQf the manufacturer.

6. Procedures for Obtaining Samples of Gas nnd Oil From theTransformer for Laboratory Analysis

6.1 Gas Sllmplcs for Labomwry Analysis. All samples of gas from the g:lS blanket abovethe oil should be taken in accordance with ASTM D3305-84 (2).

6.2 Gas DislIJolved in Oil. All samples of oil from electrical apparatus being taken for thepurpose of dissolved gas·in-oil analysis should be taken in accordance with ASTM D3613-87[4].

Under certain ronditions, stratification of dissolved gases in the oil may ~ur. and completemilling could n'lQuire many hours. In these cases, where possible, oil samples should beobtained from more than one location on the transformer.

7. Laboratory Methods (or Analyzing the Gas Blanket and the GasesExtracted From the Oil

Comparative tests on essentially identical samples of oil (for instance, from the same trans·former) by various laboratories have indicated a lack of precision, with the measured concen­tration of certain key gases reported to differ by a factor of 3 or more. The principal reasonappears to be lack of uniformity in the degree, i.e., the efficiency of gas extraction. For e:13ctand generally applicable threshold or limit values of concentrations or evolution rates of keygases, it would be necessary to obLain uniform and high (for instance, 97%) efficiencies ofedraction for individual characterislic gases.

7.1 Determination of Total Dissolved Gal. Determination oftolal dissolved gas should bemode in acc:ordWlce ",ith ASTM D2945-90 fl).

7.2 Determination of Individual Dissolved Gases. Detennination of the individual dis·solved gases should be made in accordance with ASTr.l D3612·90 [3].

7.3 Determination of Individual Gases Present in the Gas Blanket. Analysis of theindividual cases present in the gas blanket above the oil rna)' be made by using ASTM 03612·90 (3], beginning at Section 10 of that stand:.wd. Sections 13.1 and 13.2 ofASTM D3612-90 [3Jnrc not applicable in this casco

27

~~ ",~ lll~llT1JTE OF" ElEU~tC"'" I. ElEC"Ot'IC~ [1'-:III£EI'5 IIEH)I :?.?I~.. ,04 1"<>0

IEEE C57.l04 91" 48057020504378 2b7 ..

IEEESid ClI7 .104-1 991

8.1 Sources. The sources used fire:

IEEE CUIDE FOR THE INTERPR.£TA110N OF CASES

8. Bibliography

IE,.., and IEEE Transactions on Power Apparatusand Systems (PA)

Doble Indices ofMinutes ofAnnual InternationalCOllfcrCllces ofDoble Clients

lEE Procudings

Electr-ical World

Scun~ Citation Indu

Bulletin Analytique et Signaletique de France

Infonnation and technical papers supplied byMemben orthe IEEE Trflnsformer Committee(in particular a comprehensive list by T. K. Sloat>

Chemical Abstracts

Eb:c1r-ic;ul and Electr-onics Abstr-acts

CQmpendex und lnspec

8.2 Gas EvolutioD

1939-19i5

1935-19i5

1949-1972

1949-1969

196{)-1969

1950-1972

1969-1971

1973-1975

197&--1987

(81] Clerk, F. M., '"TI>e Role of DissoJved Gases in Detennining the Behavior of Mineral Insu­latin&" Oils,~ Journal of the Franklin Institute, vol. 215, p. 39, Jan. 1933.

(B2) Berberich, L. J.• "I nnuance of Gaseous Electric Disc:har-ge of H,)rdrocarbon Oils,~ Indus·tr-ial and EngiJU!er-ing Chemistry, vol. 30, pp. 280-228, 1938.

[B3] Murphy, E. J., "Gases Evolved by the Themlnl Decomposition ofPllpcr.~ Transactions ofElectrochemical S()(;iety, vol. 83, p. 161, 1943.

(B4) Vogel, }'. J., Peterson, C. C., nnd Mntsch, L. M., "Deterioration of Transfonner Oil andPaper Insulation by Temperat\1re,~AlEE Transactions, vol. 78, no. I, pp. 18-21 {tithIes), 1951.

[85J Worner, T., "Behavior oflnsulating Oil Under Dielectric Stress with Respect to G::as E\·o·lulion undlor Absorplion,- (in Gennan), Eltktrotech, Z. Desch, (Nuremberg), vol. 72, no. 22, pp.656-658,1951.

[06) Oroce, C. E. Rand Whilney, W. 8., Note on thr Quantity and Constitution of Gas Liber­ated During Arcing ill Oil CircuiJ Br-rokers. British Electrical and Allied Industries, ResearchAssociation Technicnl Reports: G'X1'35 and ClXT66 (1951) and GlI'260 (1954).

rB7l Slelchely, V. C., ~Relation Between Cas Evolution and the Physicnl Properties of Liq·uids, ~ Applud Physics, vol. 22, p. 627, 1951.

28

lar.· L, ,h 1,;"TlfUT£ OF nECT~ICAL g ElECfQ(llIIC<: [·,·lIlEr":> IIEEE.~ 01 22,:;:',0£ I~""

IEEE (57.104 91 .. 4~05702 0504379 1T3 ..

CENERATED TN O[[,.lMJ>fERSED TRANSFORMERSIEEE

Std CS7.104_1~1

rnSI Dassechf!!o, H. and McClean, D. A., MGaning of Liquid DielectriC!. Under ElectricalStre!os; lndustridi and Engineering Chemistry, vol. 47, no. 9, part J, pp. 1782-1794, 1955.

[89] Paul, Mlnformation on Hydrogen Generat.ion by fieat Decomposition ofPapcr," AlEE c.P.,pp.57-21,1957.

[BIOI Meador, J. R. Bnd Dillon, K E., 'TrOonsfonner Oil Preservation,~ AlEE Transactions onPower Apparatus and Syste.ms, vol. 33, pp. 1208-1211,1957.

[81I] HarriSOll, D., "Field Method Finds Arc-Formed Gas in Oil Filled Transformers," Eiectrj·('ai World. p. 94, August 4,1958.

[BI2} Kaufman, R. B., Pierce, J. L., and Uhlig, E. R, "The Effect ofTransformer-Oil-Preserva­tion Methods on the. Dielectric Strength of Oil," IEEE PA, vol. 34, pp.1315-1321,1958.

1Bl3] Deenan, w. J. and Doucette, G. G., "Improved Method of Oil Preservation and Its Effecton Gas Evolution," IEEE PA, vol. 28, pp. 657-666,1958.

(Bl"] BIlS$Khes, H. and Barnes, H. W., -oassing of Liquid Dielectric Under Electrical Stress,Influence of Voltage and Pressure," Industrial Engineering Chemistry, vol. 50, no. 6, pp. 959­966,1958.

18151 Krasucki, Z., Church, H. }O":, and Garton, C. G., "ANew Explanation of Gas Evolution inElectrically Stressed Oil Impregnated Paper Insulation; Journal of the Electrochemical Soci·ety, '1.'01.107, no. 7, pp. 598-602, 1960.

(816) Saito, Y. and Hino, T., "Study of'l'hermal Deterioration of Enameled Wires by the foolassSpectrometer Method," IEEE PA, vol. SO, pp. 653-657,1960.

(BI7] Rey, E. and Ehurt, L., "Die BeurieiluflG' vun inhibieTten und nicht inhibierten: lsolie­rolen fUr HochspannWlgs-Transformatoren und Mcsswandler." Bull. As•. Swis~ Elec.• vol. 52,110. 11, p. 401, 1961.

(B181 8aguhn, A. H., Reinhard, R E., and Oake, S. 4, "Gas Generation During Interruptionunder Oil," AJJ!,'E, vol. 237, 1962.

em 9] Dlodg-ett, R. B. and Bartlett,. S. C., MParnmetcrs for Predicting Gassing of Oils UnderElectric Stress," IEEE PA, vol. 55, pp. 528-536, 1961.

[820] Dnkin, T. W. and Sloat, T. K, ~Gas Generation and Its Relation to the DielectricStrength ofOil,~Electrical Insulation Conference (JESEJ, 1963, pp.13O-133.

11321] Sheppard, H. R., "The Mechnnism of Gas Generntion ill Oil-Filled Transformers," DobleConference Index ofMinutes, 1963, Slle. 6-601.

[D22) I-Iornsl>y, E. A., Irving, ft., and Patterson, E. A., "New Criterion of the Gassing l\.'Ilden·cies of Insulating Oils," Proceedings of the Institution of Electrical Engineers, vol. 112, no. 3,pp. 590--596, March 1965.

(B23) Znky, A. S. and Hawley, R., MGas Evolut.ion from Insulating Oils," Electrical Reuicw, vol.3, p. 828, June 1966.

(824) 81"Zusku, L. and Widmann, w., MZur Prufung der Gasfestigkeit von Isolierolen und Iso­Jierun{;en, Elchtrotech. Z., pt. A, vol. 88, flO. 3, p. 69,1967.

29

V> '.!>e 1I.$TIT'J1E (IF ElECTPICIol.; [LECT"OIl;:~ ['<G't.'Ef"'S lE[[l:C'JfI'C~ 1_

IEEEStd C!>7.100t_1991

IEEE (57.\04 9l .. 4~05702 0504360 915 ..

IEEE GUIDE rOll TllE D\-rERPRETATtON or GASF$

{D25] Sloat, T. K, Johnson, J. L., and Sommerman. G. M. L., ~Ga, Evolution from Trans­former Oils under High Voltage Stress," IEEE Transactions on Power ApparatllS arad System.s,vol. PA-86, no. 3, p. 374, 1967.

[826] Pedersen, G., ~Gnssing of Insulating Oils under the lnAuence or an Electric Discharge/Bfl)Wn &weri &u~w, vol. 55, no. 415, pp. 222-228, ApriVJI.fay 1968.

(8271 Morrison, E. L., "Evaluation of Thermal Stability of Electrical Insulating Paper," IEEE1l'on.sactions all Electrical Insulation, vol. £1-3. pp. 76-82, August 1968.

(828) Lipsey. G. Jo-: and Ettlinger, L. T., "PermaleJ: II Insulation System." IEEE ElectricalInsulation Conference Proceeding" pp.15D-151,1969.

[8291 Varshavskij, D. S .• ·Influence de la Valeur SpeifiQue du Dcgagcmcnt Ga.zeux Bur loDuree de Vie Descondensateurer au Papier Huile,· Izvestia Vys$hikh Uchebnykh Zovendenii •Elekcomrkhanika, no. 7, pp. 800-803, 1970.

ra30) Gusev, N. r.. -Gas Shielding of a Transformer," En.ercetik., vol. 10, p. 24, 1970.

(831] Forster, J. A and McCrae, G. G., "Gassing Tendency Tests on Service-Aged InsulatingOils; Dahle Conference Proceedings, 1974, See-IO-ISOl.

8.3 Detection and Interpretation

8.S.1 Gas Detector Relay

[B32) Bucholt, M., -rhe Bucholz Protective System and its Practical Applications; Elektro­tech. Z., vol. 49, pp. 1257-1261, 1929, (In German).

[833l"Preliminary Report of Subcommittee on Gas Detector Relay,,· listed in Advance Report{Ot' th~ 56th Ann.ual Meet.ing o{ Canadian Electrical Association Engineering Section. p. 39,June 1946.

1834J AlEE Relay Subcommittee, "Relay Protection of Power Transfonnen.... AlEE 7l-an.soc­tUlliS, vol. 66, pp. 9lJ-917, 1947.

[835] Gross, E. T. G., "Simplicity in Transformers Protection," ErectricaJ Enginuring, vol. 66.pp. 564-569, June 19017.

[n36] Madill, J. T., "'Typical Transformer Faults and Gas Detector Relay Protection; AlEETran.sactiolls, vol. 66. pp. 1052-1 OliO, 1947.

fB37] "Nipping Incipient Faults," editorial, Electrical World, vol. 128, p. 68, July 5, 1947.

(838j Gudmundsson, E., "Auxiliary Apparatus for Service Supervision and l>laintcnance ofTransformers," Journal of/he ASEA (Sweden), vol. 22, no. 10, PI). 159-167, 1949.

[O39} Streuli, W. R. ''Tranfoscope (Gas Actuated Transformer Protective Relay of Buchhol7.Type," Doble Conference Index of Minute", 1949, Sec. 6-01.

(D40) Duffy, F. H .• "Gas Detector Relay Experience on Saguenay System,· Doble C<Jnfenncf!Index of Afinute" 1951, See. 6-501.

30

9M bv U'e j'ISTIT'J-E or nECT~IC"'l ~ ELE(,T~crll':S ~"ultlH~~ .lHE)~ Cl :2,?6'O~ l"?b

IEEE (57.104 91 .. 4~O;702 05043~1 851 ..

GE....""ERATED~ OIl...IMMERSED TRANSFOR.\1ERSrEIU:

Std C57.1D-l·1991

f841 J Bean, H. L.. and Cole, H. L.., "ASudden Gas PTeuure Relay for Transformer Protection,"AlEE 7J-ansactions, vol. 72, no. 3. pp. 480-483, 1953.

[8421 Rossier, C. "Design of Large Power Trnnsformen; Bull. SteherOlt (Suisse). no. 25f, pp.9-25,1956.

1B431 Howe, V. H., Massey, L.• nnd Wilson, A C. M., 'The Identity lind Significance of GasesCollected in Buchholz Protectors," The Metropolitan VICkers Gazette, Manchester, England,vol. 27, pp. 138-148, 296, 1956.

[B44] Aptov, 1. S., "Determination of the Character of Defects Inside Transformers fronl theComposition ofGns Evolved in the Gas Relay," British Electric and Alied lndul':tries ne.~earch

Associations 7ralUaction IB1532, pp. 1-6, June 18, 1957.

[845] Hnrrison, D., 'Tnmsformer Gas Testing," Onlario Hydro Research Ntws, vol. 9, no. 4,pp. 11-15. 1957.

[B461 Sterner, V., "Report an the Work of the Study Group on Protection and Relaying. Part II:The Protection of Large Transformers," CIGRE C. R. 7hrnSQction$ (l8th SusionJ, 24 X 16, no.334, pp. 8-13, Paris, 1960.

[B47] Vanlund, J. A, "General Electric Transformers," Doble Conferenct Index of .lI,{inules,1961, Se<:. 6-301.

[B48] Sturtevant, D. D., "E:o;perience with Buchholz Gas-Operated Relay," Doble ConferenceIndex of Minutct, 1964, See. 6-101.

[B49) Seiler, H.• "Gas Test Device for Protection of Transformer,'" Electroteeh. Z, vol. 19, no. 5,pp. IIJ-116, 1967.

[B50J McDermid, w., -Generation of Combustible Gas in 230 kV Oil·Filled CutTent Trans­formers; Doble Confenru:e lrtiUz of Minutes, 1968, See. &-301.

8.3.2 Gas Cushion in Sealed Transform.ers

[B5]j Wacner, H. H., -Method Dete<:ls Incipient. Power Transformer Faults," Electrical World,p. 80, Dec. 1959.

[n52l Wagner, H. I-I., "Detect.ion of Incipient Faulls in Power Transformers by Gas Analysis,"Doble Conference Index of Minutes, 1960, Sec. 6-801.

(853) PuCh, P. S. and Wagner, H. II., "Detection on Incipient. faults in 'l'rnnsformers by GusAnalysis," AlEE c.P., pp. 60-950.1960.

[854] Wagner, H. H., "Gas Analysis Detects Incipient Faults; Electrical \\IOrld, pp. 114, June20,1960.

{85S] Pugh, P. S. and Wagner, H. H., -Detection of Incipient. Faults in Transformers by GasAnalysis," AlEE Transadions, vol. 80, pp. 189-195,1961.

[B56] Wagner, H. H., -Experience with Transfonner Gas·Fault DetectorTl!Stings," Doble Con,­ferenee Indu 0( Minutes, 1961, Sec. 6-701.

31

~1 .".. mS+HIHE OF ELECll;!CAl ;. ElECI"::fllCS Or,l.lED'S It(EEI2';:'~.. ,o.:. 1<><>"

"'£EStd C67.104.1991

IEEE (57 .•04 9\ .. 4eOS702 OS043e2 79B ..

a:££ CUrD£ I'OR TIlE INTERPRETATION O~' CASES

113571 Horelick.A 4, "Incipient Fault Detection Method Proves Valuable for Transformer Pro·teeth'e Maintenance," Tra11Jmission and Distribution, p. 34, Jan. 1961.

[B58] Bore, Gordon llnd Reichart, "'Incipient Transformer Faults Quickly Detected," ElectrkolWorld, vol. 155, pp. ao-B3,April24, 1961.

[D59] Wagner, H. B., "Pennsylvania Transformers," Dobh Conference Index of Minutu, 1961,Sec. 6-701.

1060] Duke, C. A and Tuylor, R. 0., "Detection of Combustible Gases in Nitrogen SealedPower Transformers; Doble Conference lndu ofMinutes, 1962, Sec. 6-101.

(B61] Gronberg, W. L., "Detection of Incipient Power Transformer faults with CombustibleGus Jet," Doble Omference Index of Minutes, 1962, Sec. 6-301.

r062] Wagner, H. H., "Field Experiences with the TrorJsfonner Fault Gas Detector,~ DobleConference Index of Minutes, 1962, Sec. &-801.

[863) Taylor, R 0., "TV~5 Experiences in Analyzing Combustible Gases in Nitrogen SealedPower 1Tansformers," AlEE C.P., pp. 62-528, 1962.

{B64) Rickley, A L. and Clark, R. E., "Combustible Gu Detection in Transformers; DobleConferen~ Index ofMinuteJl, 1963, See.. 6-S01.

IB6S1 Taylor, R 0., ~C<JmbustibleGas Tests Warn ofTrMsformer Failure,; Electrical World,pp. 74-75, April 22, 1963.

[866] Burrett, R D. and Parker, J. C., "Experience in 'fusling NitrOl,;en in Oil·Filled Trans·former!i; Doble Con.ference Index of Minutes, 1963, Sec. 6-201.

(B67J Cromley, R J., MFailure and Repair of a Transformer Joint,~ Doble Con{ereru::e Index ofMinutes, 1963, Sec. 6--701.

(B6S) Van lund, J. A, "Gas Analysis for Detection of Incipient Power Transfonner Faults,~

Doble Confennce Indu ofMinutu, 1963, Sec. 6--401.

[869J Vora, J. P. and Aicher, L. C., "Incipient Transformer }'ault Detection and Interpreta­tion; IEEE G.P., pp. 63-584,1963.

IB70J Bellnschi, P. L., Mlntroduction to Symposium on Gs!t Analysis for Detection of IncipientFaults in Power 'JTansformers,~Doble Con{uence Index of Minutes, 1963, Sec. 6-101.

IBn] Horelick, A. L., Wagner, H. H., and Lynch, J. C. , ~Method for Testing Electricallnstru­mentalities for Incipient Faults," U.S. Patent No. 3111 388, November 19, 1963.

[B72] Wagner, H. H., ~Penllsylvania Trnnsfonner Towl Combustible Gas (TCG), IncipientFault Detector; Doble Conference Index ofMinutes, 1963, Sec. 6-302.

(B731 Wagner, H. H., ~Progres&Report on TeG Incipient Fault Detecl.or Practice," IEEE C.P.,pp. 63-585, 1963.

IB741 Syrjamaki, E. M., ·Calibration and Comparison of Fault GllS DCtcctoT6," Doble Confer.ence Inde:c ofMinutes, 1964, Sec. 2-101.

32

< t> ·.'c 1,.:.,TI1l'lE OF ·lE(T~H.AI. " ElEctr>OUI(;~ E!;'H',EEll$ ,IFH~l ~;,JD'().t I....t>

IEEE (57.104 91 .. 4A05702 0504383 624 ..

GENERATED IN OfL-U>L".u;RSED TRANSFOR..'oU:RSIF:n:

StdC57.104·1991

{B75) Fer-guson, M. L., ~Combustible Gas Analysis as II. Prevenlive Maintenance Tool,~ DobleConference Index of Minutes, 1964, Sec 6--1801.

[D761 Duke, C. A., Goodroe, C. n., Taylor, R. 0., and Thompson, W. W., "Detection of Combus­tiblll Gases in Nitrocen Sealed Power Transformers,~ Doble Crmfp.reru:e ltldex of Minutes,19GJI, 6-1 00t.

{B7?] Wagner, H. H., "Development of Continuous Monitoring Total Combustible Cas (TeG)Incipient Fault Detector,~Doble Conference Index ofMinutes, 1964, Sec. 6-1901.

[D78) Cra;vford, C. E. and Wilson, A. F., ~Incipient Transformer Fault Detected by Combusti·ble Gas Monitoring Prob'Tllm and Ultra Sound Tests," Doble Confereru:c Index of Minutes,11164, Sec. &-1201.

(B79j Wogner, H. H., "Survcy ofTCG Tests on Transformers," IEEE G.P., pp. 6--4209.

[DBOI Parker, J. C., "Testing Nitrogen O\'cr Oil in Power Transformers," Doble ConferenceIndex of Minutes, 19601, Sec. 6-1501.

fDSl] Ferguson, M. L., "Combustible Gas Problem," Doble Conference Index of Minutes, 1965,Sec. 6-401.

[B82J Graham, W. R. and Riner, R. B., Mlncipi(mt Fault Detection in Power Tra.nsfonners,~

Doble Conference Index of Minutes, 1965, Sec. 6-201.

[B83] Wllgner, H. H., ~Five YeliTS Experience with Transfontler TeG Incipient Fllult DetccwrThsts,~ IEEE Transactions on Power Appamtlls and Systems, vol. PAS-84, no. 8, pp. 700-706,1965.

LB84] Yom, J. P. and Aicher, L. C., "Transformer Fault Gas Anlllysis Interpretntion," IEEETransactions on Powcr Apparatus and Systems, vol. PAS·B4, no. 2, pp. 172-176, discussion onp. 487, 1965.

[B85] Thomas, D. J., ~Combustible Gas in Power TransfonneTS (Its DetR.ction and Signifi­cance)," Doble CrmferelU:.e Index of Minutes, 1966, Sec. 6-1010.

lB861 Gochmauer, E. L., "TCG Analysis of Incipient Fault Forecasted," Doble Conference Indexof Minutes, 196G, Sec. 6-201.

fB871 Price, R. C., "Transformcr Failure at the Allen Steam Plants," Doble Conference Indexof Minutes, 1966, Sec. 6-301.

(E88) Rose, M., "Automatic Sampling and Measurement of Combustible Gases in TrOllsfonll­ers," Doble Conference Index of Minutes, 1967, Sec. 6-801.

[BB9] Thompson, W. W., "Modification of Conservator Transformers to Permit CombustibleGas Surveillance,~Doble Conference Index ofMinutes, 1967, See. 6-601.

[B90] Wagner, H. H., ~Penll5ylvaniaTCG Transformer Fault-Gas Continuous Monitor," DobleConference Index of Minutes, 1967, Sec. 6-701.

[B91] Sheppllrd, H. R., "Dangerous Conditions Are Detected by Analyzing TransfonnerGases," Transmission and Distribution, vol. 20, no. 2, pp. 71-74, 1968.

33

~.,. the l'JSTITUTF OF FlEC1RICAI. ~ EI.ECT~OlJICS ENGIIJEEIIS tlt(()>1 2~,3",04 lq~"

IEEEStd C51.104.1991

IEEE (57.\04 9L .. 48057DZ 0504384 SbO ..

IEEE GUIDE FOR TIlE U.'TERPRl:TAT!ON O~' GASES

[892J Hahn. J. H., "Field Un tanking and Repair of a 2301U5 kV, 40150, 3/66.7 MVA, OAIFAJFA, Autotransformer!l.~ Doble Confertnce IMIlI( of Minuter. 196B, Sec. 6-101.

(893] McDermid, W., "Generation of Combustible Gas in 230 kV Oil·foll1ed Current Trans·formen,~Doble Confeflm« lrulu of Minutrs, 1968, Sec. 6-301.

[8941 Sheppard, H. R., "Why is Gas Generated in Oil·Filled T'ransfonners?" Transmi.uionand Distribution, voL 20, no. I, pp. 63-65, 196B.

rB95] eillies, D. A. and Muckerhelde, L. H.. "Combustible Gas Monitorinl;--SOO kV CurrentT'ransformers," [)obIt. Conferenu Index ofMinutu, 1973. Sec. 6-201.

B.3..1 Dissolved Gall in Transformer Oil

(896) Clark, F M .• '"The Role of Dissolved Gases in Determining the Behavior of MineralInsulating Oils; Journal oftM PranJdin Inuitute. vol. 215, no. 1, p. 39, 1933.

(8971 Dornenberg, E. and Gerber, O. E., "Analysis of Dissolved and Free Gases for Monitor­ing Performance of Oil-Filled T'ransformers," Brown BOlleri RelJiew, vol. 54, no. 213, p. 104,1967.

[B9B1 Stamm, H. and Schul%e. w.. "Deterioration oflnsul.ators Consisting of Paper-Oil La)'ersand its Study by Gas Chromatography,- presented at CIGRE, Paper 12-14,1968.

(8991 Sheppard, H. R.. "Why is Gas Generated in Oil-Filled Transformers?" 1rafl.llmjssionand Distributwn, pp. 6~5, Jan. 1968.

{BIOOI Strom, R and Takahashi, S., MAnalysis of Fault Gases in Transformer Oil by ImprovedMethod of Gas Chromatography; Ontario Research Qunrterly, second quarter, pp. 21-25,1968.

[BIOIl Hahn, J. H., "Field Untnnking and Repair ofa 23M15 kV, 40150, 3/66.7 MVA, OA/I'"AIFA Autotrnnsformer: Doble Canferenot index ofMinutes, 1968, Sec. 6-101.

[BI021 Thibault, M. and Galand, J., "Modem Physical Chemistry Methods for Analysis ofInsulaUon Degradation in Service,M Review Generale de fElectricitt, vol. 78, no. 3, pp. 301­302,1969.

[BI031 Waddington, fo-: B. and Allan, D. J., 'Transformers Fault Delel:tion by Dissolved GasAnalyses,~Electrical Review, pp. 751-755, M.lI.Y 23,1969.

181G41 Coltong, R., "Combustible Gas Testing on Large Oil·Pilled T'runsfonners," ElectricalInslJlation Conference 69C 33EJ-37, pp.1l5-118,1969.

[DI051 Muller, R., Potthoff, K, and Soldner, K., MAnnlyse des Gas Dissous dans I'Huile enTant que Moyen de Surveillance des T'runsrormnteurs et de Detection de Defaults Naissants, ~Ilresented.at CIGRE, Paper 12-<12, 1970.

[BI06] t'allou, 8., Viale, F., Devaux, A., FOUTnie, R, Galand, J., Vuarthes, P., Davies, I., Rog_ers, R R., Reynolds. E. H., and Dornenburg, E., MApplicatioll des Methodes d'Analyse Physico­Chimiques A l'Etude des Degradations dans I'lsolation des Materiels Eledriques," presentedat CleRE, Paper 15-07,1970.

34

"'. by th 1'~T:I'JIE or CUCiPl('.Al I HEClROU1CS [!V,)!l;;[U'l> (!E[[l~ 01 ~~,3<>,()£ 1_

IEEE CS7.10~ 91 .. ~60S702 OSO~36S ~T1 ..

CENEllATED IN OIL-IMMERSED TRANSFORMERSlEEE

Sld C57.104·1991

[BI07) Moraro, D., Popesco, C.• Stoic&, M., and Tanaseseo, F. I, -Detection des DegradationsProduite5par des Decharges PaTtielles pour les Types d'bolation Papier-Huile." presented atCIGRE. Paper 15---05, 1970.

(8108) Wilputte, R., -Contribution a l'Etude de I'Evolution de Gas dans les Isolnnu LiQuideset Solides Soumis a rAttion de Contraintes Electriques,- presented at CIGRE, Paper 15---03.

(SI09] Beer, G., Onerii, A., Bossi, A., Hjrra, C., "Contribution ezperimenLnle 8: I'etude de 1adegradation produiLs par les delchargu partielles dans Ie papier isolant impregne a. I'huile;presented at CIGRE, Paper 15-02, 1970.

(8110) Discussion ofPapeTS from Group 15 (Insulating Materia!), presented a1 CIGRE, 1970.

(8111 J Lindeman, K., -Analyze Transfonner Gas To Identify Faulta," Power, vol. 114, no. 4, p.74,1970.

(81121 "Detection of Developing DaDlage in Transformer; Gorchokollo Elek. Sta., vol. 41, no.4,p. 51, 1970.

(8113] Ishii, T. and Namba, S., "Les Gu Produits LoTS de 10 Deterioration de l'Isolation des'ITansfonnateurs; Jour1UZ1 of the lnstitute of Electrical Ertginur. of Japan, vol. 90, no. 5, p.910,1970.

[O1l4) Dind, J., Daoust., R, Regis, and Morgan, J .• -Analysis of Gases Dissolved in 'ITans­fonner Oil,- Doble Conferena./Il(fu: of Minutes, vol. 38, AlC71 , 1971, Sec. 6-U01.

(BllS) Morpn-Schaffer CeJrporlltion, rra.n,fonntr Fault Ddedwn &flIice.

(BlI6] Collins, R. L.. -Hydrogen Detector," US Patent 3 559 457, 1971.

(DU7] Stoll, P. and Vuillemier, C., -Une Methode ChromaloiTaphiQue de Mesure Absolue deC02 dans I'Huille des 1'ransfonnateun; BuU. Ass. Suisu Elee., vol. 62, no. 23, p. 1113, 1971.

(8118) Hino, T. and Suganuma, Y., -Rapid MealUTement of the Deterioration of Oil.ImmersedI'aper,~Eketricol/n,ula1ion Conference, 71 C 38EI-41, 129,1971.

rB119) Davies, 1., MComposition oflhe Gases Formed in Electricallnsul!lting Oils: Journal ofApplied Chemi!!ry and Bio!ec;hnolO{JY, vol. 21. p. 194. 1971.

lD120) Thibault, M. and Galand, J., "Methodes Physico-Chimiques d'Etude de DCr,Tadntionsen ServiCC,R Rell. Gen. Eke., vol. 80, no. 1, p. 46, Jan. 1971.

fB121) Thibault, M. and Galand, J., "M:ethode, Physico.Chimiquel d'Etude de Degradationen Service; ReI). Gen. Eke., vol. 81, no. 1, p. 48, 1972.

18122) Daoust, R., MAnalysis of GasCll Dissolved in Transfonner Oils,R Doble Confuenu IndexofMinutu, vol. 39, AlC71,1972, Sec. 1()....601.

(BI23) McCrae. G. G_, "Experience with Incipient Faults Detection by Gas·in-Oil Analysis:Doble COIlfu'cnoe /ndero( Minu!u, vol. 39, lAC72, 1972, Sec. 6-101.

(8124) Hardy, Hurworth, and Robinson, -Diagnostic Testing of 1'Tens(ormer Insulation byGas-in-Oil Analysis: presented a1 SUPEC 72 Conference, University of Bradford, 1972.

35

by ~"e WSlllUIE OF ElECIIlICAL & ELEC1R(J-llCS F.tlGltlEEIl$ (IEEEI12,J40,~ lq<jl>

IEEESld C57J04-l991

IEEE (57.~04 9~ .. 4605102 05043~b 333"

1£££ GUID£ FOR nm INTt:RPR£TAnON OF GASES

(8125) ~CasAnalysis as an Aid to Transfonner Fault Location; EI~ctric 7Tmu, vol. 161, no. 5,p. 46. 1972.

181261 Cameron, D. I.. "Gas-in-OilAnalysis: A'Thol for Early Warning of Equipment Trouble,~presented at CEA, Spring 1972.

[B1271 Barraclough, B., Bayley, E., Davies, I., Robinson. K., Rogers, R R., nnd Shanks, E.•KCEGB Experience of the Amdysis of Dissolved Gas in Transfonner Oil for the Detection ofIncipient Faults," I n TEE Conference Publication, no. 94, Sec. 1, Part 2. March 1973.

[8128) 8allaschi. P. L.. "Application of Fault-Gas Detection Methods on Transfonner Test atthe Factory," Doble Conference Twx 0{ Minutrs. 1973, Sec. 10-301.

(8129] Pugh. D. R., "Combustible G8I Analysis,· Doble COTIferrna Iru;ux 0{ Minutes, 1973.Sec. 10-401.

{BISOJ Martin. W. 8. Jr.• and 1'I.ylor, R. 0., -Experience with Chromatcgraphic Analysis ofFault Gases in Power Transfonners; Doble Conference Index 0{ Minutu, 1973, Sec. 11)....201.

[8131) Booker, J. R., "Ellperience with Incipient Fault Detedion Ulili:ting Gas Chromatogra­phy Analysis,- Doble Confuen~ Index ofMinwtJ, 1973, Sec. 10-.501.

[B132J Raab. E. L., "Symposium on Gas Chromatography: Doble Confereme Index of Min­ules, 1973, Sec. 10-501 A.

fBI33l Yamaok, M. et al., "GJO Analyser (Auto.Analyser for Gases in Oil),~ Fuji Elretr. Rev.(Japan), vol. 19, no. 2, pp. 83-86, 1973.

18134J Smimov, M. A. et al.. "Gas-Content of the Oil in Working Transformers," Elektr. Ston­tsii (RusJ, no. 8, pp. 57-60, 1973.

(BI35] Pugh. D. R., "Advances in Fault Diagnosis by Combustible Gas Analysis: Doble Con·ferenu Indu ofMi.nut~$,1974, Sec. 10-1201.

rB136) Beeler. G., "Cambustible Gas Analysis on Peach Bottom No.1 Transformer: DobltCOIIferrnce 1nOOo(Minutes, 1974, Sec. 10-1401.

[BI37) Keene. D. J., -rransfonner Problem Delected by F.o.uItrGosAnalysis," Doble Confer­tmt Tndex ofMinutes, 1974, Sec. 10-1301.

[8138] Duval, M., "Fault Gasu lo'ormed in Oil-Filled Breathing E.H.V. Transformers; Inter·prel.Rlion of Gas Analysia D.o.ta,· IEEE C.P" no. C 74, pp. 476-478,1974.

[lU39) Domenburg, E. and Strittmatter, w., -Monitoring Oil Cooled Transformers by GasAnalysis.- Brown Bovui Revitw, vol. 61, nO. 5, pp. 238-247. May 197<1..

[8140) Muller. R, Schliesing. H., and Soldner, K., "Testing and Supervision of Transformersby Analysis oftbe Cases Dissolved in the Oil,- Ehlt.trizitoetswirlsch4tt (Germany), vol. 73, no.239.pp.683-687.1974.

[8141]" Discussion From Group 15 ((nsulating Materials): CIGRE Conference Proc:rrdings,vol. 1.1974.

3.

'.I,IM try ~h.. WSTITUTE Of' ELECUlIUol. !. [lEClllONICS EH3WHRS IIHE!s..p 01 22,:>t>,().ol tQ<Jt>

IEEE (57.11J4 91 • 40305702 QS043B7 27T •

GENERATED IN OIL·1MMERSED TRANSFORMERSIF.F.E

9t.d C5? .1Q.f-19111

[BI42} Rogers, R. R., "U.K Experience in the Interpretation of Incipient Faults in PowerTransformers by Dissolved Gas-In-Oil Chromatographic Analysis,~DobIe Conference Index ofMinutes, 1975, Sec. 10-201.

IB143] Armstrong, G. W. Jr., and B::aker, A. E., "Transformer Problems Detected or Confirmedby Use ofCombustibJe Gas Analysis," Doble Conference Index of Minutes, 1975, Sec. 1()-301.

[B144J Dvoracek, E. and Walla, J., "Analysis of Gases Dissolved in Transformer Oils." Enerae­/ika, vol. 15, no. 1, pp. 8-11,Jan.1975.

[D145J Pejovic, V. and Bojkovic, A., "Control of Transformer Insulation Systems by Gas Anal­ysis," Thknika (Yugoslavia). vol. ao, no. 5, pp.~, 1975.

[B146] Thibault, M. and Rabaud, J., "Application of the Analysis of Dissolved Gases to theMaintenance of Transformers," Rev. Gen. Elec., vol. 84, no. 2, p. 21, Feb. 1975.

IB147J Dind, J. E. and Regis, J., "How Hydro·Quebec Diagnoses Incipient Transformer Faultsby Using Gas-in·Oil Analysis," Pu.lp Paper Can., vol. 76, no. 9:T264, Sept. 1975.

[B148] Davies, I. A., "'Review of Methods for Examining the Analysis of Gases in Oil FilledElectrical Equipment, With ObselVations on the Concentrations Found and Their Depen­dence an Time," G.E.G.B., Paper No. SSD/SElRR/68J75.

[B149] Hubacher, E. J., "Analysis of Dissolved Gas in Transformer Oil to Evaluate Equip­ment Condition," P.C.E.A. Engineering and Operation Section Spring Conference, March1976.

(BI50) Tsukioka, H., Sugawara, K, Mori, E., Hukumori, S., and Sakai, S., "New Apparatusfur Detecting H2, CO, and CHi Dissolved in 'lTansformer Oil," IEEE 'I'ransactions on Electri­cal Insulation, vol. EI-18, no. 4, pp. 409-419, Aug. 1983.

[BI5Il Lampe, W., Spicar, E., and CarTender. K.., "Gas Analysis as a Means of MonitoringPowcr Trallsfonners,~ASEA Journal (Allmaenna Svenska Elektrisha Aktiebol!llget), vol. 52,no. 2, pp. 39-42, 1979.

[BI52l DiGiorgio, J. B., Jakob, F., and Haupert, T., 'Transformer Fault Gas Analysis," min­utes of the meeting of Pennsylvania Electr. Assoc. Eng. Sect. Electr. Equip. Cerom., Bedford.PA. Oct. 18-19,1977. Published by Pennsylvania Electr. Assoc. Eng. Sect., HafTisburg, p. 22,1977.

(B153] Aiyar, D. and Nanda, J. R., "Identification and Estimation orGnses DissO'lved in Elec­tric!!l Insulating Oil by Gas Chromatography," Electric India, vol. 16, no. 9, pp. 17-21, May15,1976.

lDI5-1] Tsukioka, H., Sugawara, K, More, E., Hukumori, S., and Sakai, S. , "New Apparatusfor Detc<:ting H2, CO, and CH4 Dissolved in Transfonner Oil," IEEE Transformer EkctricalIMulation (USA), vol. EL-18, no. 4, pp. 409-419, Aug. 1983.

[B15sJ Surakka, M. L., "Gas AnRlysis of Oil Monitors Transformer Condition," Modern PowerSystems {USA}, vol. 3, no. 4, pp. 60-61, April 1983.

[B1561 Surakka, M. L. and ,Jaakkola, V. K.., "Gassing Properties ofTransfonner Oils," Pre­sented at Nordisk Isolation Symposium, 1982, Odense, Denmark. Published: ASEA, Stock­holm, Sweden.

37

'y th. INSTlTUT£ OF ElfCTRIClll & ELECTRONICS ENGINEERS II((EI22,36,04 n~6

IEEEStd. CS7.llM.lelll

1E[E (57.104 91 .. 4605702 05043&8 lOb ..

1£EE GUIDE FOR THE D-."TERPRETATJON OF CASES

(DIS?] Kelly. J. J. and Myers•. S. D., "The Value of Gas-in-Oil Analysis as II Guide to theOperational Conditions Existing in a Power Transformer," Conference Record of the 1972Thirty-Fourth Annual Conference of Electrical Engineering Problems in the Rubber and Plas­t.ics Industries.

rB158J Yamada. H., Nomura, Y., Kat.ayma, Y., Ishii, '1':, Imamura, 0 .• and buchiyama, K..,'"Automatic: Field Monitoring of Dissolved Gas in Transformer Oil," IEEE TrallSformer PowerApparatus and Systems (USA), vol. PAS-lOO, no. 4, pp. 1538-1544,AprilI981.

[13159] Brasel. E. and Langec:ker, K., '"E.traction of the Gas Dissolved in the TransformerOil," EleJctrie (Germany), vol. 34, no. 12, pp. 637-641,1980.

(B160] Kan, B., '"Automatic Dissolved-Gas Analyzers for Transformer Monitoring," Mit:tub·ilfhl" Electric Adt> (Japan), vol. 12, pp. 8-10, June 1980.

[B161] Groves, B. C. and Brinkworth, D. C.• "On-Line Gas·in-Oil Monitor," CEGB nchnicalDisdosun Bulletin (GB), no. 349, pp. 1-2. June 1980.

rB162J Kelly. J. J .• 'Transformer Fault Diagnosis by Dissolved-GuAnalysis: presented atIEEE 26th Annual Petroleum and Chemical Industry Conference, pp. 145-151, 1979. SanDiego, CA, Sept.10-l2, 1979.

(8163J Rogers, R. R, "IEEE and IEC Code. to Interpret Incipient Faults in TranlformersUsing Gas-in-Oil Analysis: IEEE Transforme,. Eleetricallruulation (USA), vol. EI-13, no. 5.pp. 349-354, Oct. 1978

[B164] Belanger, G. and Duval, H.. "Monitor for Hydrogen Dissolved in Transformer Oil,·IEEE Transfonner Elmricollnsulation (USA), vol. EI-12, no. 5, pp. 334-340, Oct. 1977.

{DIG51 Kauffman, G. H., "Gas Bubbles in Distribution Transformers; IEEE TransformerPower Apparatus and Systems (USA). vol. PAS·96. no. 5, pp.1596-1601, Sept.-Oct. 1977.

[BI661 Shirai, H., Shimoji. 5., and Ishii, T., 'Thermodynamic Study on the Thermal Decompo­5ition oflnsulating Oil," IEEE '1hJruformer ElectrkallnsuJation (USA), vol. EI-12, no. 4, pp.272-280, Aug. 1971_

(B167J Muller, R., Schliesing, "., and Soldner, K, ·Assessing the Operational Stale ofTrana­formers by Gas Analyai5," EleJctriziJ.oetw;irtschoft (Gennany), vol. 76, no. 11, pp. 345-349,May 23, 1977.

[B1GB] Glass, R. H.• "Dissolved GasAnlllysis ofTrnnsfonner Oil," 'n-ansmisswn and Distribu­tion (USA), vol. 29, no. 1, pp. 22-24, 26, 28-29, Jan. 1977.

[B169] Domenburg, E. and Hutzel. 0., "Operational Supervision by Testing the InsulatingOil; Ele.lttrotech. Z. A (Germany), vol. 98, no. 3, pp. 211-215, March 1977.

(B170] Heinrichs, F. W, "'I'he Impact of Fault-Detection Methods and Analysis on the Trans­former Operating Decision," presented at IEEFJPES Transmission and Distribution Confer­ence, Paper 86 T&D 559-9, Anaheim, California, Sept. 1986.

(DI7l) Haupert, T. J., Jakob, F., DiGiorgio, J .• and Sperry, M., "Use ofTransfonner Oil Anal·ysis for Reducing Equipment Failures," Electrical World, vol. 192, no. 7, 1979.

38

I'''t by 0.... INSTI1UIE OF (LEctPIC"," " HEClROIllCS ENGTIlEEPS !lEUI~p 01 22,36,(),( \qq6

IEEE (57.104 91 • 4B05702 0504369 042 •

GENERATED m OIL·IMMERSED TRANSFORMERSlEEE

SldC57JQ.I,·I991

[BI72) Jokob, F., Haupert, T. J., ond DiGiorgio, J., ·Cut Failures by Analy>;ing TrnnsfonnerOil," Electrical World, pp. 52-54, Oct. 1, 1979.

[BI73] Jakob, P., Haupert, T. J., and DiGiorgio, J., "New Technique Pinpoints Fault Loco.tions," Ekctrical World, pp. 119-121, May 1981.

[B1741 Church, J. 0., Haupert, T. 0., Jakob, F., "Analy:t.e Incipient Faults with Dissolved GasNomO£Taph,~Electrical World, Oct. 1987.

[B17S] Haupert, T. O. and Jakob, F., "A Review of the Operating and Practice of Dissolved GasAnalysis," Ekctricallnsulation Oils, STP 998, pp. 108-115, 1928.

[B176) Haupert, T. 0., Jakob, F., and Hubo.cher, E.J., "Application of a New 'Thchnique for the1nterprelation of Dissolved Gas Analysis Data," Il1h Annual Thchnical Conference of theInternational Electrical Thsting Association, PP. 43-51, 1989.

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y the INSTITUTE OF ElECTRICAl! ElECTRONICS ENGINEERS (IEEEI22.36,04 1"1"16