Document O3zk2BmGLepY0vx68gDoZJEgM

ELiCTHIC GENERAL ELECTRIC COMPANY, *70 LEXINGTON AVENUE. NEW YORK. N. Y. 10022 Phon* (212) technical RESOURCES SUBJECT: Benefits of PCB Use December 30, 1971 Dr. Edward J. Burger, Jr, ' Executive Office of the President Office of Science and Technology Room 4224, New Executive Office Building Washington, D. C. 20506 Dear Dr. Burger, . Accompanying this letter Is a statement descrlting the benefits to the public arising from the use of polychlorinated biphenyls in the electrical Industry. It is submitted in response to your invitation to prepare material for the consideration of the Office of Science and Technology in supporting the work of the Interagency Task Force on PCB. Whereas there is a growing body of literature on the wide dispersal, toxicology, and ecological significance of this class of materials, nowhere do we find adequate treatment of the unique proper ties which have occasioned its use in electrical apparatus, nor of the advantages of safety, reliability, and economy which have ensued. Our paper is offered to help remedy this lack and thereby assist in arriving at a balanced comparison of pxfclic risk with public benefit. There is ample indication that the environment carries a significant burden of some forms of PCB. This burden derives, we believe, in some measure from the untutored waste disposal practices of the recent past, but principally from the nonelectrical uses (e. g., as plasticizers in paints and plastic materials and as hydraulic and heattransfer fluids in industrial machinery). It is our belief that the pattern of restricted use, process control, and waste disposal engineering now being put in place by voluntary Industry initiatives in the U. S. and England will, if adopted also in other PCB-producing countries, prevent significant increase in this burden. The key feature of this program is to limit HONS 207047 GENERAL^ ELECTRIC Dr. Edward J. Burger, Jr. -2 December 30, 1971 application to sealed electrical apparatus. Our calculations indicate that tho portion of electrical PCB possibly reaching the environment from field disposal and repair activities is being rapidly reduced and may be already below 1 percent of total electrical industry usage in the United States. In the near future, this class of waste should be the only category remaining, as effluent from manufacturing plants approaches zero and the nonelectrical applications are cut off at the source. The residual field waste from electrical apparatus is itself subject to further improvement, and ways to accomplish this are now under study by the C -107 Committee of ANSI. If these efforts succeed in preventing an absolute increase in such discharges as the power industry continues to grow, the contribution to the nation's total environmental burden would be so low as to require more than a thousand years to double the burden. To the extent that this assessment is confirmed by further study and future developments, it would appear that we need have less, concern for the technical problem itself than for the possibility of legislation or regulatory rulings which fail to take into account the special circumstances of electrical industry usage or the public benefits which would fall victim to any undifferentiated prohibition of PCB use. The attached report has been prepared by a team of General Electric scientists and engineers in less than two weeks, in accordance with your recommendation of a preliminary document at the earliest possible moment. Accordingly it is neither exhaustive in its treatment nor completely consistent in the format of presentation for the various applications involved. Please let us know if you or your colleagues desire more information on any of the points covered in the statement, or clarification of any obscurities, and we shall do our test to supply the deficiency. Thank you for the opportunity to introduce consideration of PCB benefits into the deliberations on this important public question. JFM/rs Att. WV I J-r/n,-- i ijpeiy * * ! I iF'f V/j. F. McAllister Manager-Product Quality Corporate Executive Staff i General Electric Company MONS 207048 I -3- IHTR0DUCTI01T Fol'chlorlnated blphenyle (FCB) have baan uaad In a vide variety of Induatrlal and eonauaar appllcatlona ovar tha paat 40 yaari, but It vaa only racantly that avldanea began to appear that theaa material* had bean widely dlaparaad throughout the environ ment. By latter dated February lg, 1970 tha Moneanto Company, a aola US producer of FCB'a, notified ell of Ita cuetomere of'tha potential problem of environmental contamination" by theaa llqulda and recommended "that all poaelble care ahould be taken in tha application, proceeelng, and affluent dlapoael of theaa producta to prevent them becoming environmental contamlnanta." Moneanto haa begun a program to dlacontlnue aalaa of FCB'a for uaa in palnta, plaatlclaara, epaclalty lnka, adhaalvaa, paper coatlnga and all other opan-ayatem appllcatlona. ` Tha Moneanto Company haa declared, however, that It will continue to aall FCB'a for cloaed-ayatem electrical uaaa. Thla declalon la a tacit recognition of tha Important role that FCB'a play In tha aafa, reliable, end efficient delivery of electric power from the generating plant to tha uaar. In tha apete of publlahad raporta and atatamanta that have appeared in recent f yeara on FCB'a there haa bean no meaningful axpoeltlon of thla role of FCB'a In electrical equipment -- why, where, and how they are uaad; what eltarnetlvea are available; and what tha conaequencea would be to the uaara of auch equipment If FCB'a ware no longer avr.llable. Ua hope that thla report will provide ouch an *w*%*a l,F 4 a* MONS 207049 -4JWCKCROUHD PC*'* Are ued by tha elactrlcal induatry a* components f cartaln cypaa of transformers and eapacltora. Tha nature and function of thoaa davlcaa ara da'acrlbad In tha aaparata aectlona of thla report davotad to than. At thla point It la sufficient to aayi ' 1, Tranafornara ara davlcaa for converting alactrleal power froa one voltage and currant level to another and tha conducting perta of thaaa davlcaa auat be separated froa .each other by a suitable Inaulatlng *aadlua* 2* Capacitora ara devleee for atorlng electrical energy through tha phyalcal aaparatlon of charged aetel aurfacaa by an Inaulatlng medium. Prior to 1930 tha most coaaonly uaod Inaulatlng aedlua waa alnaral oil. Tha aarly 1930'a aav tha coaaarclal davalopaent of Inaulatlng liquids that vara mixtures of aynthatle chlorinated aro- aetlc hydrocarbona, principally varloua polychlorinated blphenyla. By controlling tha eoapoaltlon of theae alxturaa, the aanufncturer could obtain daalrad coablnatlona of theraal, chealcal and dielectric propertlaa that reaultad in Inaulatlng liquids with auch greater oxidation and flra raalatance than alnaral olla. During the paat 40 yaara theae liquids have becoae widely uaed in cartaln cypaa of tranaforaara and eapacltora and bra racognlaed aa a dlatlnct claaa of Inaulatlng aetarlala dealgnated by tha International ' tern "aakarel". The definition of tha tara *'aakarel", the composi tions- of tha liquid that eoaprlaa thla claaa of aetarlala, and the varloua tradeaarke by which they are known eoaaarclally are described In tha following section heeded'"Aakarel".* _ MONS 207050 -5Tho particular askarels used in transformers and capacitors are different; so also ere the reasons for, end the extent end - consequences of, their use In these two types of electricel equip ment. However, certain general comments can be made et this point concerning their use in both types of equipment} 1. .`.skarel-insulated transformers end capacitors are delivered to customers as sealed units from whleh there Is no escape of askeral under normsl operation during their expected lifetimes of 10 to more than 30 * years. Hovevor, certain types of equipment failures can rupture the case and permit the loss of some askarel to the environment. Such failures occur at a rate of about 0.02X of the units In service per year, 2. fCB's can get Into the environment during the menu- * facture, delivery, Improper use, maintenance, repair, and disposal of transformers and capacitors. In ' sddltlon to specific control measures Instituted by Individual menufecturere and recommended by them to the equipment users, the American Rational Standards Institute has established ANSI Committee C107 on Use end Disposal of Askarel Used in Electrical Equipment. Its memberships (see Appendix 1) Is divided Into separate working groups on transformers - and capacitors whleh will recommend national standards end procedures necessary to prevent the loss of fCB's to the environment et ell stages from equipment t manufacture through.ultimate, disposal. e 3. The record of reliable end safe performance that _________ eskarel-lnsulsted transformers end capacitors hsve HONS 207051 "6compiled during Che past, four decade* is reflected in Che various codes, standards, and regulations th'at now effectively require or encourage the continued use of esksre1-Insulated equipment in any applications* HONS 207052 I -7A$ KAREL Pc CInltlons' 1. A Synthetic nonflammable Insulating liquid which, when decomposed by the electric ere, evolves only nonflammable gaseous mixtures. . '. (From the Netlonel Electrical Code 1971 end the American Netlonel Standards Institute C-42 series, "Definitions of Electrical Terms.") 2, The tern asksrel generally describee widely used, broed class of nonflemma'ble synthetic hslogeneted hydrocerbon e insulating liquids used ss electrical Insulating media. Askerels of various compositional types are used. Under arcing conditions the gases produced, while consisting of predonl. nsntly non-eombustlble hydrogen chloride, can yield varying amounts of combustible gases depending upon the eskarel type. Insulation systems Incorporating these sskerels end celluloslc or other organic materials may, when arced, * gaseous mixtures which are moderately flammable*. <, . */ (From ASTM (American Society for Testing end produce t Materials) Method D 2283-71, Fart 29, 1971 issue; will also appear in the 1972 issue of the IEEE (Institute of Electronic end Electrical Engineers) "Guide for Acceptance and Maintenance of Transformer _o Askerels in Equipment.", Adoption was also recommended to the International Electrotechnical. Commission by Its Subcommittee 101 (Insulating Liquids Other then Hydrocerbon Oils) 'of Committee 10 (Liquid end Gaseous Dielectrics) as reported In Item number 9 of minutes l 'A4(SC^10B *..Merch,,1971. HONS 207053 Polychlorinated biphenyls are derivatives of the hydrocarbon, biphenyl, which haa the chealcal fornula C12H1(). From one to ten of the hydrogen atone la a aolecule of blphonyl can be replaced by chlorine atoae, end the chemical Identity of the resulting chlorinated compound depends both on the number of chlorine atone that have been Introduced Into the aolecule end on the specific sites In the molecular structure et which they ere Introduced. The commercial material aanufectured by Monsanto under Its registered trademark Aroclor consists of mixtures of these specific chlorinated compounds. They ere usually Identified by the weight percent of chlorine In the total mixtures, e.g. Aroclor 1254 con tains 541 chlorine. The Aroclors commonly used In the electrical Industry are Aroclore' 1260, 1254, and 1242. ,f Aroclor 1242, used primarily In capacitors, contains about 71 of pentachloroblphanyls and higher. In September 1971 Monsanto Introduced a new capacitor-grade askarel, Aroclor MCS-1016, which Is essentially Aroclor 1242 that has been specially proceesed to reduce the content of pentachloroblphanyls and higher to lose than i/ * 0.4X. As a general rule, the nonflammability of liquid FCB's, their vapors, and their are-formed gaseous products Is greater the higher the degree of chlorination of the liquid. Studies by Monsanto suggest that the resistance of FCB's to degradation In the environ '* ment may also Increase with Increasing chlorine content* Analytical methods for low levsle f-FCl'a (reported In parts per million or parts per billion) In marine, aquatic, and wildlife environments do not always Identify the specific compounds that ere present, but In Its letter of February 19, 1970 to Its ouatomers, Monsanto stated' thst "FCB's with,a chlorine content of less then 541 have HONS 207054 -9- not been found in the environment and appear to proeent no potential problem to tha environment." Trademarks ` '' t Tho following tradonarka are uaed by cloetrlcal manufacturer* to designate the askorels usod ip their products! Manufacturer Trademark AtrovoK i . Allis-Cbalmers . Hyvol Chlorextol American Corp. Abestol Cornell Dubilier Dykanol General Electric Pyranol Kuhlman Electric Saf-T-Kuhl Slemex Sangamo Electric ' Disc lor Wagner Electric Noflamol Westinghouse Electric Inerteen Toxic and Biological Effect* of PCB'a Systematic investigations of the toxic and biological effects of FCE's have been undertaken only within the past few years, and the description and evaluation of the results is beyond the scope of this report* Some investigators suggest that reports of certain toxic reactions may be ceused by highly poisonous compounds (e.g. chlorinated dlbensofurans) found to be contaminants in some PCS preparations* In the United States, medical records show that over a nearly 40*year period the only adverse health effects experienced by US workers exposed' to PCB's, either during the manufacture of these liquids or of electrical equipment containing these liquids ,have been limited to occasional eases of non>chronlc * t* chloracno or other temporary skin lesions or irritations* HONS 207055 -10TRANSFORMERS Definition , . .. A transformer ! device for transferring electrical energy from one alternating current circuit to another fey electromagnetic means. It haa no moving parte and performs lte function fey linking two electric current carrying circuits (the coils, ^usually copper wire} via a comon magnetic v *' flux carryIng-circult (the core, usually a special gradesf Iron). A transformer may be designed to effect a change In voltage or current from one circuit to the other or simply to ofetaln elcctrifesl energy from one electrical circuit without making a conductive connection between It and a second electrical circuit, - The transmission of electrical energy from one point to another Is t essentially tho transmission of a retired number of kilovolt-amperes (kvs). By Mans of transformers the kva's may fee generated at a low voltage suitable for the windings of generators, stepped up to higher voltages and lower currents suitable for transmission of electricity over long distance wires, snd then at the desired destination stepped down to a lower voltage and larger current suitable for utilisation fey electrically powered equipment. The almost universal use of the alternating current system for the trans mission and distribution of electrical energy la largely due to this ability of transformers to link up circuits of different voltages and currents. Thus the generator, the transmission lines, the secondary distribution system, and finally the great variety of ultimate loads can each fee operated at the vol ,/ tage most suitable to Its particular function. Without this unique ability of the transformer to adapt the circuit voltage to the Individual require ments of the different parts of the system, the enormous development and progress In the transmission and * distributiof n of electrical energy during the past 60 years would udt have been possible, ~ HONS 207056 -11Why Asksrels are Used in Transformers The coll* end coro of most transformers ere enclosed in tested me tel tsnks thet ere filled with en Insulating liquid, ususlly mineral oil. Under certeln conditions of sudden power surges high-current electric ercs ere producod Inside the transformer which cen generste end ignite flesmable end explosive ges mixtures formed from the mineral oil end other celluloelc In- "** sulstlng components In the trensformer* ' ,, Beceuse of the nonflammablllty of liquid sskerels, their vapors, end their erc-formed geeeous products, trensformer* filled with etkerels ere free of these fire end explosion hazards end may be used In locations whers fellures of oll-lnsuleted transformers would present e potential danger to life end'property. This safety factor Is the only advantage thet askarel* Insulated trensformers have over oll-lnsulated transformers of the seme site end rating. The density of sskerels Is about 1.7 times thet of mineral oil, so askarel-lnsulated trensformer* ere heavier than their oil-filled counter parts. Askerels themselves ere more expensive than mineral oils, end their solvent characteristics require the use of more expensive Insulation compo nents on the Internal parts of the trensformer, so the complete units ere more expensive. As a consequence, askarel-lnsulated transformers have captured only those market applications (less than 51, hut growing) where considerations of safety and reliability are paramount. Their use In such applications Is usually required or encouraged by the provisions of electrical codes, fire underwriting policies, or governmental regulations. # Wote: Prior to the add-1950's the liquid used In askarel-lnsulated transformers was a 50-50 weight mixture of Aroclor 1260 (60S chlorine) with trlchlorobcntenes; then the benzene component was changed to a mixture of trl- end tetrachlorbcnzenes; and I*n 1971 the Aroclor component was changed to Aroclor 1254 (541 chlorine)* -' _ HONS 207057 -12- Types and Application) of Aakarol-Insulatcd Transformers Thoro iri two broad clasc1 float Ion* of transformer: power transformer*, which aro usod to step up voltages; and distribution transformors, which n used to *tp down voltages, Tha many typos of transformer* that are Included within these two classifications era listed in Appondlx 2, The applications that accompany tha listing apply only to those unit* of a given type that are manu factured with askarel a* the insulating liquid. Meat unite of- tha typos Hated are still oil-insulated. We estlmata that tha total number of askarel-insulated units that have baen put into service in the United States since 1932 is 125,000, and virtually all of these units are still in service, The lifetime-before-failure is often longer than 30 years, and almost all units that do fall are rebuilt and returned to service. Tha current production rate of new askarel-insulated transformers units is about 5,000 par year, . Most of these transformers are located inside public, commer cial, or industrial buildings; on tha roof tope of such buildings; or in close proximity to such buildings, and require no special enclosures other than what are necessary to prevsnt accidental haaardous mechanical or electrical contact of persons with the equipment* However, the National Electrical Code does specify vault# for the Indoor installation of askarel-insulated transformers rated more than 35,000 volts* Askarel-lnsulatsd transformers are ,4 limited by the electrlal properties of these liquids to ratings below 69,000 volte* ' The amount of askarel used in various types of transformers ranges from 40 to 500 gals. (516 to 6,450 lbs.) with an average of about 235 gals. (3,032 lbs,). During 1966, the last complete "normal" year for the electrical industry, the total amount of HONS 207058 -13l'Clt'e used 1 tran former! was approximately 1.3 million p.olloni (C.4 thousand tons). Piciicnt Alternative! to Agkarcl-Insulated Trans formert If TCB'c were Lo be no longer available for closed-syiten electrical uses > as they are no longer available from Monsanto for open.system applications - vhat alternatives to askarcl-Insulated transformers could now be supplied by the electrical Industry, and vhat would be the effect upon the user should sskere1-lnsulated transformers no longer be available either as new or replacement units? ' .. The only present alternatives to askaral-lnsulatad transformers are oll-lnsulatcd transformers or dry-type transformers (either those open to the atmosphere or thoee that arc gas-filled and sealed) i ' A. 011-1nsulstcd transformers ' 1. If one disregards safety considerations, there sre no technical reasons why oll-lnsulsted transformers could, not be directly substituted for asksrol-lneulatcd transformers. The also of the unit'would be unchanged; . . the weight end cost would be lessj 2, There ere legal' restrictions' to such a direct substitution* _ , , a* Some local regulations (e.g. Chicago) prohibit * the use of oll-lnsulatcd unite In certain locn- ' clone whoro aakarol-lnsulated unite are allowed, b. Where oil-lneulatod transformers would not be specifically prohibited oe^on-elto replacements for asUsre1-insulated units, the National .Electrical Codo imposes special restrictions * * upon their uodc of installation* Although HONS 207059 -14- 3 5000 volet mutt bo installed In vaults, til o11-lntultted Crtntformer require vaults, except that eltornetive fire protection srrsnge- nente tre permitted for unite rated not over 600 volts. Assuming that specs were evellsble Inside en existing building to accommodate these special auxiliary safety provisions, the cost of their construction could range from $5,000 to $50,000 per transformer, c. Oil-Insulated units can be Installed outdoors . if they are suitably Isolated from flammable structures or If these structures are suitably safeguarded against fires originating in the . transformers. The power output must then be brought to the point of use inside the building via cables or Insulated buses, and the eoet of cable and bus Installation could also range from $5,000 to $50,000 per trans former* The outdoor transformer would have to be of a higher rating than the Indoor one It would replace because of voltage drop and - consequent power losses la the cable or bus . rums. i g. Pry-type transformers , In most locations, dry-type transformers (either those open to the atmosphere or those that are gas-filled and sealed) eould not be directly substituted for ssks'rel-insuleted'transformers. There are several - restrictions to such a dlroct substitution: r r - HONS 207060 -15- 1, The provision! of Che National Electrical Code ere more stringent for certain cleeeee of dry- type tranifoneera then for comparable liberal- insulated units. '- 2. Present technology' Is not available for design ing and manufacturing reliable dry-type trans formers above KVA end/or 15 KV. 5, The reliability of dry-type transformers Is lass than that of comparably rated llquld-lnsulated transformers* Oil- and aakarel-lnsulated units show muchgreetor resistance to switching end lightning surges then do dry-type units. An EE1 survey of failures In network transformer banks showed e 71 per year failure rate for dry-type units comparod to 0.21 for llquld-lnsulated units* Furthermore, llquld-lnsulated transformers have e much greater overload capability. Many llquld-lnsulated units can sustain a 1001 over- load for 8 hours and e 2001 overload for 2 hours. t These transformers ere able to maintain continuity of electrical service during periods of tsmporery outage of related equipment* , 4* Some dry-type transformers ere larger by 10 to 301 then comparably rated llquld-lnsulated units, end ( moat ere more expensive. t * 5, Dry-type trensformere are noisier by 5-10 dg then ere llquld-lnsulated transformers. t. Seceuso their Insides require regular cleaning, .* . the maintenance costs for open dry-type transformers arehlgher then those for seeled dry-type transformers HONS 207061 or for liquid-insulated transformer, which arc also sealed. 7. Open dry-type tranaformera, which are cheaper * than sealed dry-type transformers, cannot bo used in certain corrosive or hatardous atmospheres, e. g. on furnaces or on electrostatic precipitators near hot stacks. * Summary . 1, For technical or legal reasons It would be Impossible to replace most askarel-lnsulated transformers now In service by oll-lnsulated units of equivalent rating and reliability wLthout major construction changes that would be required to compensate for the fire and explosion resistance of the aakarel- lnsulated units. 2. For certain applications and locations, dry-type transformers could replace askars1-insulated trans formers, but with a significant reduction In system ' reliability. HONS 207062 -17- CAPACITORS Pc finitlon t A capacitor 1* a device that stores electrical energy, it consists of two metal eurfecee or electrode# separated by an insulating medium euch a# air, paper, plastic film, or oil. When a voltage ie applied acroaa the electrode#, electrostatic energy i# stored in the insulating aadlua. In typical industrial capacitore the electrode Material la aluminuM foil and the insulating aadlua or dielectric is paper tissue and/or plastic flla,which for aany applications la impregnated with a liquid dielectric. A liquid lapregnent la uaed to fill the volda within the paper or plaetlc flla structure, to fill the voids between sheets, end to contribute to the capacitance or charge* carrying ability of the coaposlte. Voids aust be ellalnated within capacitors that ere to be used above 200*300 volts, which exceeds ths dielectric breakdown strength of air. In our definition of transforaers we eaphaslaed their importance In the transmission and distribution of electrical power (kilovolt amperes) froa the generating plant to the ultimate load. If the load were purely resistive (e.g, an electric heating element) no further Modification of the power supply deliverod to it would be required. Other loads (o*g* induction aotors) aay require that a portion of the kllovolt-aaperes delivered to thea be used to pro vide a Magnetising current, which does not contribute directly to the useful power output of the load. This portion of the total kva delivered to the load la designated as reeetlve kilovolt-amperes (kvars). It has bean found aore econoaleal to produce kvars from ' *4 total kva's noar the point of load rather than near the point of generation, and capacitors provide the aost efficient way of HONS 207063 -18- cffecting thi* tran*formation tc Che point of load. Why Aakarcl* are Ued in Capacitor* Prior to 1930 noat liquid-filled capacitor* vara made with ainaral oil* Tha aubaaquant aubatitution.o aakaral* for tainaral oil taada poaaibla algnlflcant taehnical laprovaaanta 1ft tha alee, reliability, and Ufa of thaaa capacitor** A. Siaa Tha tingle aoat important propart/ of a liquid to ba uaad in a capacitor ia ita dialactric eonatant (tha ratio of ita ability to atora alactroatatic energy ralatlva-to air). Tha dielectric eonatant of capaeitor-grada aakaral (Aroclor 1242) ia 5.85 while that of ainaral oil la 2*25* Whan capacitor tiaaue la impregnated with the** liquid* the dialactric *i i eonatant of the paper-liquid coapoaita la 6*1 for , aakaral and 2.9 for ainaral oil. Furthermore, bacauaa of the relatively clone aatch between the dielectric conatanta ofcelluloaa, (8.8) and aakaral (5.85), It la poaaibla to atraaa aakarel-*lapregneted paper to 400-500 volta'/all*, while the atraaae* that can be applied to comparable paper-alneral oil capacitor* are Halted to 300-350 volta/all. The combined effect of theae technical advantage* of aakarele haa beam to peralt a reduction of capacitor . also* to leaa then 14X of whet theywere la 1924* _ In 1985 e new dielectric ayatem conalatlng of paparpolypropylene flla-eakarel waa Introduced with atreaa capability up to 900 volta/all. overall. Bealdoa . favorable atreaa dlatrlbutlona, the ability of aakarel --------- - * n. t ner*a aft'.-t he ,,d la 1 a c tr 1c atrength of polypropylene HONS 207064 -19- is partly responsible Cor this Improvement. Reliability and life Askarels are thermally and oxidatively mors stable 9 than alncrel oils, and dischargee, which can occur In capacitors, ara less likely to generate gaaaa Iron askarele than Iron mlnoral oils. The chsmlcal stability of askarels In the presence of capacitor tissue and plastic films and the favorable stress distributions between solid and liquid referred to above have made It possible to design low-coat capacitors with a life expectancy of more than 10 .years life In lighting applications and more than 20 years In electric utility applleatlona. In each application the first-year failure rates are less than 0.2X, This lsvel of life and reliability had not been achieved prior to the Introduction of ' askarels, Furthermore, the non-flammablllty of askarala la greater than that of mineral oil, which reduces the fire hasard that might otherwise accompany those failures that result In' ruptura of ' the case. ` Uhcreae the transformer manufacturer has had to essentially "deelgn around" the properties of askarels in order to be able to take advantage of the safety factor that they Impart to hie equipment, the capacitor manufacturer has been able to "dselgn with" the properties of askarala and obtain significant technical improvements along with the Improved safety * ** factor. As a.result askarels have virtually supplanted mineral oils in mors than 90X of the power and Industrial .e V'11 * * ihm J ^ ****** PI' w T* HONS 207065 Hotc ; I -20Prior to 1952 the liquid used In sskare1 -imprcgnated capacitor* va* Aroclor 1254 (54% ehloTin*)} It vn then replaced t by Aroclor 1242 (42% chlorine), which ha* batter aleetrical propertle and a* noted in the. "Aakarel" section, in September 1971 Monsanto introduced new capacitor-grade askarel, Aroclor MCS-1016, which 1* a modified Aroclor 1242. Unlike askare1-lnsulated transformer*, the liquid in askare1-imprognated capacitors contains only Aroclora and does not contain added chlorobanxenes. Type* and Application* of Askar*1-impregnated Capacitors The principal types of askarel-lmpregnat*d capacitors and their applications aro described in Appendix 3. Almost 80 million such capacitors sre manufactured annually, most of them for first time use. Unlike transformers, capacitors are not rebuilt and, returned to service after failure* They are disposed of (ee* "Background" section, item concerning ANSI Committ* C107) and replaced by new capacitors. . Capacitors used in lighting and air conditioning applications contain 0*005 to fesftM gals. (0.05 to 1.0 lbs.) of askarel per unit. The largest power capacitors' contain about 6.7 gals (77 lbs.) of askarel* The most popular slse contains about 3.1 (36 lbs.) 9 The National llectrlcal Cod* requires'that any Installation of capacitor* in which any single unit contains more than 3 galloqj of combustible liquid shall be in * vault Ilka that required for transformers. .During 1968, the last complete,"normal" year * for the electrical Industry, the total amount of PCI's used in capacitors was approximately 14.4 thousand tons. HONS 207006 f*sit 1` r e ' < i' L A 1 nni' t 1 v r r. to A 1 1 ..u i 1 - T npi r, n.it^d Capacitors . I rcu's were to be no longer available fur closed.system electrical uses -- ac they arc no longer available from Wonr-onto for open-syatew`applications -- what alternatives to aekarel-imprcgnatcd capacitor* could now be supplied by the olcctrleal industry, and vhat would be the effect upon the user should askarcl-imprcgnatcd capacitors no longer be available cither as now or replacement units? Possible alternatives to askar el -itr.pr c gnat ad capacitors arc copncitorn impregnated with mineral oil, or capacitors impregnated with certain other liquids. I A> Wineral Oil - -. ' Roplacement of aakarela by mineral oil would essentially return capacitor technology to its prc-1932 level. Some specific consequences of such a replacement would ba; 1. Safety. Kona of tha possible liquid alternatives to askarels are nonflammable, and a fire hazard ' would be created by any capacitor failures that 1 were accompanied by rupture of the case. Presently the use of copaeitors containing flammable liquid Is governed by the National Electrical Code *Articlcc 4C0 and SOI. - ' a,- Size and Cost. A few specific examples wl.il illustrate . the size and eost penalties associated with a switch from sskarel to mineral oil in capacitors. The most , popular slzod power capacitors today arc rated at 200 UVAR. If mlnaro'l oil were substituted for askarel the volume of the capacitor would be _ quadrupled nnd the direct labor and material cost* associated with Jtfs manufacture would Increase by 70U. Today power capacitors arc available in 400 uvak HONS 207067  *. * KVAIt becoMie of increased hct di*siption problem* with Increased volume. In addition to increases in dirset costs, the povor capacitor Industry would face lncrossed capital expenses estimated at $2,000,000 to provide the increased velum* of material at projected X.VAR requirements. Steel companies faced with increased sice, cost and flsmmabllity of capacitor banks for induction heating furnaces vould probably not install new ' induction heating capability* Utilities would have difficulty with substatlon-site in crowded urban areas. An increase in the sit* of capacitors for air conditioning would not ba critical. In lighting applications a 3.75/.075 uf 540 VAC rating for high output applications is typical. If mineral oil war* substituted for askaral, tho capacitor vould be 71% larger and materials would coat 46% more. Lamp ballast manufacturers vould have to Increase the sice of the ballast to accommo- ii .t data the larger capacitor. This vould change the thermal performance of tha unit and require U.L. approval of new ballast deslgne. Lighting fixture manufacturers vould also face redesign costa to take larger ballasts. 3. Reliability. User* of capacitors lnall application areas, have come to expect long life and very low initial failure rates. The present performance stan dards have been achieved after many years of field testing and accelerated testing by manufacturer* and users. i The reliability of designs containing HONS 207068 -23- mineral oil in many applications would be uncertain. Available records show that capacitor reliability # prior to the availability of askarel vae only a fraction of what it la today. 4. Replacement Market. The implicationa of changes in capacitor sice have been, discussed in terma of new designs. In each major application area soma capacitors ere sold for replacement business. Power and induction heating capacitors are generally installed in recks of a few to thousands of capa citors. It would not be possible to make simple substitutions for failed capacitors while main taining the system rating. In air conditioners replacement of failed capa citors might be as simple ee Installation of new brackets* On the other hand,' tight designs might ni>t take a larger capacitor at all. Lighting systems would be seriously affected by increases in capacitor else. Larger replacement ballasts would not fit into existing fixtures without altered mounting arrangements. It is possible that apace requirements would force complete replacement of lighting fixtures for the want of a replacement ballast. 5. Material Sources, Mineral oil is currently used in a relatively small number of specialty capaci tors* In this country there is a single source of capeeitor-grgde mineral oil with limited e facilities for acid refining of crudes from a single oil field. mpr*irm > * * * Increased demand would require e y ~ s * * * * * w* -m, HONS 207069 -2/1. expanded facilities and Investment and considerable development In defining technical requirements for copacitorgrade mineral oil. a Efficient use of. mineral oil in capacitor designs would require higher density capacitor tissue . than Is currently produced In this country* At the least this would require extensive paper machine modification. Capacitor winding techniques and machines would need to be developed for winding tighter rolls. ' B. Other Liquids . * 1. Castor Oil* The dielectric constant of castor ell is 4,5 and this material la useful as an lmpregnant in D.C. energy storage capecltors. However* A*C* capacitors filled with this liquid have relatively ehort lives and are not very stable under A.C* dischargee and in the presence of water derivable from the celluloslc paper* 2* Plbutyl sebaeate* This ester Is especially useful In high frequency parallel plate capacitors because of its low, flat lose characteristics over a broad frequency ranged In this type of construction the . liquid la the sole dielectric material* When used In conjunction with paper* this eater la also unstable* ' . e 3* Silicons Fluids, These materials have a dielectric constant of 2*7 end would generally be subject to a .the seme disadvantages ae mineral oil' ' t, C. Alternative Pe'algna ' In addition to liquid dlalactrlc substitutes* alternatives ^ ' t* 'T f i HONS 207070 -25 to the paper-liquid dielectric night bo considered These would involve the use of plastic film costed with aluminum foil or vapor-deposited aluminum m electrodes. Since the free volume of the system is lees then that of paper the capacitance of the syaten is less dependent on the dielectric constant of the liquid end the stress distribution between the plastic films and low dielectric constant liquids is more v closely balanced. Such dielectric systene are difficult to construct completely free of voids. It la expected that several years will be required to achieve the required level of reliability in such dielectric systems. HONS 207071 possiiii.r nnvn.nrMi'.NT or nnu tnmji.ai'tnc; i.tquxds The coat ftf askfircl liquids is about $2.00 per gallon, compared to about $0.30 per gallon for mineral oil. Thus, long before there were any environ* mental concerns about PCD's there was a strong economic lnoentlvo to find o.tlicr less--xpensive insulating liquids with the dfesirable characteristics of aeknrolt, Since the 1930's, at least 10 major chemical or electrical companies have Invested large amounts of time and money in this search, all with no success. There arc todsy no flulda that can be uacd aa one-for-one replacements for PCB't. The continued search for new fluids would probably stsrt with fluorochemicals. Fluorochemical! arc nonflammable, nbntoxlc, and as far as is presently known represent no environmental hazard. High-boiling fluorochemicals might thus be potential replacements for PCD's. Considerable laboratory study, over st * least a one-year period, of the physical, chemical, and dielectric properties of these materials would bo required in order to identify specific candidate materials, . At lceat another year would be required to develop e finished product based upon a fluorochomical. On one hand, the physical and dielectric properties would certainly be sufficiently different so that substantial engineering redesign by ` electrical manufacturers would bo required to accommodate a fluorochemical. On the other hand, a one-year lead time la needed to construct a chemical plant to produce the identified fluorochemical In the millions of pounds that would be required par year. Furthermore, a significant program of environ mental testing would be needed to ensure that the new material was indeed not an ecological hazard. The foregoing arc all highly optimistic time cotina The cost of manufacturing fluorochemicals la inherently high. Prices of .' high-boiling liquids are $10 - 15 per pound, orhlglicr. At best one would Jiopc MONS 207072 I ._ that in aufficient volume the price might epproech that of Teflon, currently $3 - it per pound. Even thia optimletic figure le approximately twenty tine* the coat of PCS'a, and ainca the value of PCS in a tranaformer la roughly onc-tcnth the total value of tha tranaformer, the total coat of a fluorochemical-lnaulated tranaformer would be at leaat three tlmea that of an equivalent aakarel unit. HOMS 207073 >****. *yr -28- t Appendix 1 ftenbcrahip of ANSI Committee C107 on Use and Disposal of AaVcarel Used In Electrical Equipment Humber of Represent*tivea 2 2 1 1 1 1 2 1 1 5 2 2 1 1 Organisetlon Represented Department of the Army * Environmental Protection Agency f U.S. Department of Agriculture Tannaaaaa Valley Authority Ceneral Services Administration national Bureau of Standards Certified Ballast Manufacturers Association Edlaon Electric Inatltuta Institute of Electronic & Electrical Engineers National Electrical Manufacturera Association Monsanto Company Commercial Haste Disposal Companies Engineering Consulting Firm Capacitor Manufacturer Serving as an Independent Member HONS 207074 I Appendix 2 Typci of AsVerel-Insultted Transformer* * A. Distribution Trent former* ,` , 1. Network (up to 2500 KVA) 2. Single- end three-pheee (up to 2500 KVA) 3. Pole-nounted end etetlon (up to 500 KVA) . ' The epplleetlon of these transformer* in power dlsttibution eye tent pieces e greet premium upon their reliability end high overload capability (which they there with comparable oil-insulated units): such es 1001 overlotd for S hours end 2002 overloed for 2. hours. ,4, Precipitation (high voltage DC) These trensforners ere pert of the power supply for electrostatic precipitators, which ere gaining increasing use in preventing sir pollution by particulate natter. They ere generally installed close * to hot gas stacks in an etnosphere that would be a fire haeard to oll-lnsulated transformers and a corrosion haxard to open dry-type transformers. Sealed dry-type transformers are impractical for high voltage DC. ' * 1, B. Power Transformers - * 1, Secondary substation , ' * .. * a. Load center units '- . b. Secondary substation generation unite c. Switchboard unite ,, d. Integral unite -\ a. Kotor control unite * ' .' ,, " These5carpels* the largest group of aakarel-insulated transformer*, i* end tbsy find widespread application in the automobile, paper, .* , HONS 207075 -30i . $3 chemical, textile, eteel, uonferroua me tel, cement, mining, end pottoleum induetriee. They ere uaed in commercial end public bulldinge, euch ee echoole end hoapltala; in defence end nucleer energy inetelletione; end by prlvete end public utilitlee. 2. Meater unit aubetetlon, ' 4 3. Primary unit eubetation 4. Limited ampere eubetation 5. Induatriel furnace . , Theae tranafoimera are uaed in the hot, dirty atmoephere in proximity to gleea melting end Induction furnacea, which require high current, low voltage power auppllea (more then 2500 KVA at no more then 13.8 XV). Exiatlng technology doea not permit conatruc- tlon of aealed dry*type trenaformere for theae power retlnga, 8. Rectifier Theae trenaformere ere uaed for large rolling milla end DC induatriel power auppllea, end ere covered by the aame commente given for induatriel furnace trenaformere, *' ^, 7. Tranaportatioa e. Third rail - ' Theae trenaformere ere uaed for rapid trenalt ayateaa, end ere baaically aervlng e rectifier function, b. Locomotive ` Trior to 1932, ell on-board trenaformere were open drytype. Beceuae of probleme with them, rallroada went to eekerel-lnaulated trenaformere. The changea in locomotive deelgn alnce the 1930'a r, would not now accomodate open dry-type trenaformere ee replacementa HONS 207076 T^P -31- for askarel units. A recent trend has been to replace aakarel by 611 units, and this will continue unless new DOT regulation* require nonflammability. 8. Multiple-unit car (MU) These transformers are mounted under the flat-bed of passenger cars. They ride along In this location, about 8 inches above the rail, at speeds up to 150 mph. The transformer must be ruggedly built to with stand the impact of flying debris and constant vibration. Power to the cars la brought in through an overhead catenary and la fed to the underside of the car where the transformer, controls, and propulsion equipment are located. Present voltage la 11 KV. but new electrification la expected to be 25 XV. , Space and weight are critical in this application, There are only about 33 inches above the'rail. The width of the transformer la limited by the width of the car. Only oil- or asksrel-lnsulated units would provide the required performance levels in the apace available. A* with locomotive applications, present DOT regulations do not restrict the use of flammable liquids, i" and tha use of askarel units has been dictated largely by the economic considerations of firs Insurance rates. HONS 207077 - J i. - i . I (' ' _ ' Appendix 3 - Types of Askarol-Insulated Capacitors ' * 'i* Hlfch Volteae Power * , ` . Generally AC capacitors are uaed Co improve the power factor of a circuit. Power fcctor la the ratio of true power in watta to the apparont power aa obtained by multiplying the currant flowing to Che load by Che circuit voltage. The power factor correction can be made directly at the load or ac utility aubatatlona. In the latter caaa high voltage unlca will be dealgned for 4,600 to 13,600 vole earvica. To the utility engineer .the uaa of cepaeltore ir purely a matter of econdmlea. The main beneflta chat rtault from tha uae of capacitora are i 1. Reduction of loaaaa aaaociatad with tha delivery of alectrl- , cal power to tha point of uae. 2. Reduction of tha lnveataant required in equipment for da* llverlng electrical power to the point of uaa, which may be broken down into) a. Reduction of currant for the aerne kilowatt load. b. , Reduction of tha kva racing of equipment required to ' handle the came kilowatt load. e. Reduction of the voltage drop for a given kilowatt load. 4, Control of. delivered voltage if the capacitor kv la varied. . ** t Slactrlc utilities also use capacitor banka in aarlea with diatri- butlon clrculta to Improve voltage regulation. High voltage utility capacitora, low voltage power capacitora, and induction heating capacitora are manufactured at tha rata of 200,000 per year, about 2 to ' * 31 of which are for replacementa; tha balance are for new installations. * , ** . -V k * i 4 e * * 1 ' e % . HONS 2070 78 -33- B. Lou Voltage Power Capacitors Inatailed In induetrlel plants *t the demand eite (typi cally large motors and welders) are designed for 230 to 575 volt service. Capacitors Installed near the loads are the-most efficient way to supply the magnetising current to produce the flux necessary for the operation of in'uctive devices. Bates for the sale of power are generally struc tured to encourage power factor correction at the site* eliminating the noed for the electric utility to transmit both power-producing current and magnetising current all the way from the generator to the plant site. The same considerations apply to Induction heating applications, the principal difference belhg that capacitors for this rapidly growing appll- ' cation are designed for operation at 960 to 9600 Ha. C. Lighting Capacitors Improve the efficiency of lighting systems. A fluorescent or mercury vapor lamp`can be ballasted without the use of a capacitor, but the power factor of the lighting system would then be In the range of 50 to 601. For comsierclel or industrial lighting with either fluorescent or high Intensity discharge lamps* the use of a capacitor in the circuit b provides part of the lamp ballasting and brings system power factor into the range of 90 to 9)1. The current market for these applications is about 44*000,000 units annually of which about 101 are estimated to be replacement ballasts, ji 0. ftlr Conditlonina ' ' ' As in the lighting applications, the capacitor improves system effi ciency. Air conditioners could be made to operate without capacitors, as do home refrigerators* but because of the higher capacity required for current air conditioners* the resultant line/would virtually eliminate home "plug- 1 lne" and would still further overburden.a seriously threatened national HONS 207079 * J - power network. Almost all air conditioner pump motors are of the split winding type on which the capacitor provides phase differential for the . so-celled start winding, thus delivering good starting torque. The proper size capacitor permits high (90% ) power factor after start-up. The current market for this application is about 12,000,000 units an nually, with about 5% of these estimated to be for replacement usage. E. Industrial Electronics This market category la a catchall covering many varied eppllcationa, two important ones being motor run and power aupply applications. Motor run appliestions are for pumps, fans, and farm feed equipment, and do not differ significantly from air conditioning applications. Ths power supply market uses capacitors principally to provldt high power factor, but through careful design ths capacitor can also provide wave shaping whera deslrtd. The market ia estimated et 23,000,000 units per year with no estimate as to ths ralatlvt slat of ths replacement market. HONS 207080