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Transformer Oil
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Petroleum oils have been used in electrical equipment since
the latter part of the last century. Sebastian de Ferranti,
who
might be considered to have been the father of the
transformer, recognised their benefits as long ago as 1891.
heir performance has been improved a little since then, both
as a result of better refining techniques and in the way in
which they are selected and used. hey still represent a
veryimportant component of much electrical power plant.
Firstly, it is appropriate to loo! a little at the sources
and
production of oil.
"ll types of mineral oils are obtained from crude
petroleum,
which is said to have been formed from buried and decayed
vegetable matter or by the action of water on metal
carbides.
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#rude petroleum is defined by "merican Society for esting
and $aterials, "S$. %&88 as follows'
A naturally occurring mixture, consisting predominantly
ofhydrocarbons which is removed from the earth in liquid state
or is capable of being removed.
Crude petroleum is commonly accompanied by varyingquantities of
extraneous substances such as water,
inorganic matter and gas.
The removal of such extraneous substances alone does not
change the status of the mixture as crude petroleum. If such
removal appreciably affects the composition of the oil
mixture then the resulting product is no longer crude
petroleum.
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here are three main groups of hydrocarbon molecules.
hese are paraffins, napthenes and aromatics.
(ach has a characteristic molecular structure, and no twocrudes
are e)actly ali!e in the relative proportions of the
hydrocarbon types or in the proportions and properties of
the
products to which they give rise.
$any classifications have been proposed for the varioustypes of
crudes, but the most generally accepted is that
based on the main constituent of the distillation residue
and
consists of four descriptions' paraffinic, asphaltic, mi)ed
or
intermediate, and napthenic.
he world*s !nown supply of crude oil is made up of
very
appro)imately + per cent paraffinic, 18 per cent asphaltic
including - per cent napthenic and +- per cent mi)ed or
intermediate.
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Typical analyses of crude oils classied as naphthenic andparanic
showing actual proportions of aromatics, naphthenesand parans
present
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PROPERTY REQUIREMNTS OF LIQUID
DIELECTRICS EQUIPMENT ESSENTIAL PROPERTY
DESIRABLE PROPERTY
TRANSFORMERS
Chemical stability t!a"#sO$i#ati%& The"malDe'"a#ati% a%#
(y#"lysis The"malcha"acte"istics )#the"mal c%#*cti+ity
(i'hs,eci-c eat *i#s
N% T$ic Bi#e'"a#able Cm,atibility !ith
t"a%s/"me" c%st"*cti%
mate"ials0 M*t*al cm,atibility !ith
the" t"a%s/"me" Fl*i#s0 Easy "ec%#iti%i%'0 Easy t ha%#le.
S2ITC( )EARS
L! ca"b% /"mati% )# a"c 3*e%chi%' )#
L*b"icati%',",e"ties
0N #e,siti% / sli# ""esi%*s mate"ials !hile#ecm,siti%0L!
Flammability.
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COMPOSITION
• Paraffinic base crude predominantly paraffinic hydro
carbon, high wax and bitumens.
• Naphthenic base crude predominantly naphthenic &
aromatic, less wax, more bitumens.
• Mixed base crude intermediate between paraffin and
naphthene. Both wax & bitumens.
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Types of Transformer Oil
)e%e"ally the"e a"e t! types of Transformer Oil *se# i%
t"a%s/"me"&
4. Pa"a5% base# T"a%s/"me" Oil6. Na,htha base# T"a%s/"me"
Oil
Na,htha il is m"e easily $i#i7e# tha% Pa"a5% il. B*t $i#ati%
,"#*ct i.e. sl*#'e i% the %a,htha il is m"e sl*ble tha% Pa"a5%
il. Th*s sl*#'e / %a,htha base# il is %t ,"eci,itate# i% bttm
/ thet"a%s/"me". (e%ce it #es %t bst"*ct c%+ecti% ci"c*lati% /
theil& mea%s it #es %t #ist*"b the t"a%s/"me" cli%' system.
B*t i% the case / Pa"a5% il alth*'h $i#ati% "ate is l!e"
tha%
that / Na,htha il b*t the $i#ati% ,"#*ct " sl*#'e is i%sl*ble
a%#,"eci,itate# at bttm / the ta%8 a%# bst"*ct the t"a%s/"me"cli%'
system. Alth*'h Pa"a5% base# il has ab+e me%ti%e##isa#+a%ta'e b*t
still i% *" c*%t"y it is 'e%e"ally *se# beca*se / itseasy
a+ailability.
A%the" ,"blem !ith ,a"a5% base# il is its hi'h ,*" ,i%t #*e tthe
!a$ c%te%t b*t this #es %t e9ect its *se #*e t !a"m climate
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Parameters of Transformer Oil
he parameters of ransformer /il are categori0ed as,
1. (lectrical Parameters %ielectric Strength , Specific
2esistance, %ielectric %issipation Factor.
&. #hemical Parameter 3 4ater #ontent, "cidity, Sludge
#ontent.
5. Physical Parameters 3 6nter Facial ension, 7iscosity,
Flash Point, Pour Point.
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Density Density f ! "i#uid !t $emperature%t 's $he Mass
of $he "i#uid ccupying (nit )olume at $hat$emperature
$est Method* IS: 148 (Part 16) – 1977
+aluating Methods*•-ydrometer Method
•Density Bottle Method
Density ange* /.01 2 /.03 4 5 6c7acilitates 8eparation of 7ree
il & il with Dissoled
Moisture
-igh )alue f Density 2 Poor -eat Dissipation
6haracteristics
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Viscosity of Transformer Oil
6n few wards, Viscosity of Transformer Oil can be said
that7iscosity is the resistance of flow, at normal condition.
/bviously resistance to flow of transformer oil means
obstruction of convection circulation of oil inside the
transformer.
" good oil should have low viscosity so that it offers
less
resistance to the convectional flow of oil thereby not
affecting
the cooling of transformer. ow viscosity of transformer
oil is essential, but it is equally important that, the
viscosity of
oil should increase as less as possible with decrease in
temperature. (very liquid becomes more viscous iftemperature
decreases.
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KINEMATIC VISCOSITY Meas*"e / Resista%ce t )"a+ity
Fl! /
a Li3*i#& The P"ess*"e (ea# Bei%',","ti%al t its De%sity
UNIT:CENTISTO;ES IS: 4??@
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Dielectric Strength of Transformer Oil is also !nown
as Breakdown Voltage of transformer oil or BDV of
transformer oil.
:rea! down voltage is measured by observing at what voltage,
spar!ing starts between two electrodes immerged in the oil,
separated by specific gap. low value of :%7 indicates presence
of
moisture content and conducting substances in the oil.
For measuring BDV of transformer oil, portable :%7 measuring
!it is generally available at site. 6n this !it, oil is !ept in
a pot in
which one pair of electrodes are fi)ed with a gap of &.- mm
in
some !it it ;mm between them. s and observe the voltage at which
spar!ing
starts between the electrodes. hat means at which voltage
%ielectric Strength of transformer oil between the electrodes
has
been bro!en down
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ELECTRICAL STRENGTH(rea!"o#n $olta%e&
Meas're of resistane in !ilo$olts re)'ire" to*rea!"o#n t+e oil
aross a s,ei-e" %a, 'n"ers,ei-e" on"itions.
Meas're of a*ility to #it+stan" eletrial stress
In"iate" 0 "etets t+e ,resene of free #ater1 "irt1moist're1
ell'lose -*re or on"'tin% ,artiles.(E2e,t "issol$e" #ater1 ai"s1
sl'"%e&
T+e mi%ration of #et soli" matter of ontaminants
to t+e stresse" area *et#een eletro"es lea"s toformation of
strin%s to *ri"%e t+e %a,
Lo# $al'e of DV in"iate" ,resene ofContaminants 0 Moist'res 0
Con"'tin% ,artiles.
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DIELECTRIC TRE!"T#
The #ielect"ic st"e%'th / a% i%s*lati%' il is a meas*"e /
theils ability t !ithsta%# elect"ical st"ess !ith*t /ail*"e.
The test i%+l+es a,,lyi%' a ac +lta'e at a c%t"lle# "ate
tt! elect"#es imme"se# i% the i%s*lati%' *i#. The 'a, is as,eci-e#
#ista%ce. 2he% the c*""e%t a"cs ac"ss this 'a, the+lta'e "ec"#e# at
that i%sta%t is the #ielect"ic st"e%'thb"ea8#!% st"e%'th / the
i%s*lati%' li3*i#.
C%tami%a%ts s*ch as !ate"& se#ime%t a%# c%#*cti%',a"ticles
"e#*ce the #ielect"ic st"e%'th / a% i%s*lati%' il.Cmbi%ati% / these
te%# t "e#*ce the #ielect"ic st"e%'th t a'"eate" #e'"ee.
Clea% #"y il has a% i%he"e%tly hi'h #ielect"ic st"e%'th b*t
this#es %t %ecessa"ily i%#icates the abse%ce / all
c%tami%ates&it may me"ely i%#icate that the am*%t /
c%tami%a%ts,"ese%t bet!ee% the elect"#es is %t la"'e e%*'h t
a9ectthe a+e"a'e b"ea8#!% +lta'e / the li3*i#.
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Specific Resistance (Resistivity) of Transformer Oil
his is another important property of transformer oil. his is
measure of %# resistance between two opposite sides of
onecm5 bloc! of oil. 6ts unit is ta!en as ohm3cm at specific
temperature.
4ith increase in temperature the resistivity of oil decreases
rapidly.
?ust after charging a transformer after long shut down, the
temperature of the oil will be at ambient temperature and during
full
load the temperature will be very high and may go up to 9@o
# atover load condition.
So resistivity of the insulating oil must be high at room
temperature
and also it should have good value at high temperature as
well.
hat is why specific resistance or resistivity of transformer
oil
should be measured at &+o# as well as 9@o#.
$inimum standard Specific 2esistance of ransformer oil at 9@o#
is
5-A 1@1& ohm cm and at &+o# it is
1-@@A1@1& ohm cm.
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Specific Resistance (Resistivity)
Measure of Vou!e Resistance"
Resistivoity # $c %ectic %ie& ' urrent $ensitiy
actors *ffectin+ Resistivity
•on&uctin+ I!purities
•Pro&ucts i,e *ci& an& Su&+e
•ree Ions an& Ions for!in+ partices
•Moisture
-estin+ Stan&ar&.IS61/0
i!its: 2e3 oi 1// % 15 ! 57 c
0 % 15 ! 9/ c
Service oi : /"1 % 15 ! 9/ c
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Dielectric Dissipation actor of tan delta of Transformer oil
%ielectric %issipation Factor is also !nown as loss factor or
tan delta
of transformer oil. 4hen a insulating materials is placed
between
live part and grounded part of an electrical equipment,
lea!age
current will flow. "s insulating material is dielectric in
nature
the electric current through the insulation ideally leads the
voltage by
9@o. Bere voltage means the instantaneous voltage between live
part
and ground of the equipment. :ut in reality no insulating
materials
are perfect dielectric in nature.
Bence electric current through the insulator will lead the
voltage with
an angle little bit shorter than 9@o. angent of the angle by
which it is
short of 9@o is called %ielectric %issipation Factor or
simply tan delta
of transformer oil.
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$ore clearly, the lea!age current through an insulation does
have two component one is capacitive or reactive and otherone is
resistive or active.
6t is desirable to have loss angle as small as possible. So
we
should try to !eep the value of tan C as small as possible.
Bigh value of this tan C is an indication of presence of
contaminants in transformer oil.
Bence there is a clear relationship between tanC and
resistivity of insulating oil. 6f resistivity of the insulating
oil is
decreased, the value of tan3delta increases and vice verse.
6n one sentence it can be said that, tanC is measure of
imperfection of dielectric nature of insulation materials li!e
oil.
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Dieletri "issi,ation fator
(3o#er fator 0 tan "elta 0 loss an%le&
Q*ality c%t"l test Meas*"e / Dielect"ic lsses i% il
Re+eals ,"ese%ce / c%tami%a%ts ,ic8e#by il > #e"i+e# #*e t
$i#ati%.
P" ma%*/act*"e G ba# *se /e3*i,me%t
(i'h +al*e / DDF lea#s t i%c"ease#
4. (eati%' lea#i%' t the"mal "*%!ay6. C""si% G $i#ati%
H. 2ate" sl*bility a%# em*lsi/yi%' ,!e"
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L! +al*e / DDF > e%s*"es /"ee#m
/"m mist*"e& ,la" cm,*%#s&sl*ble im,*"ities a%# mi%im*m
e%e"'ylss
L! Ta% Delta > i%c"ease# 'assi%'
Resisti+ity G Dec"eases hy#"sc,icity Limits
Ne! il JK C J.JJ6
Oil i% se"+ice JK C J.6 F" 4?; class
4.J F" 4?; class
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$ater Content in Transformer Oil
Mist*"e " $ater Content in Transformer Oil is
hi'hly*%#esi"able as it a9ects a#+e"sely the #ielect"ic ,",e"ties /
il. The
!ate" c%te%t i% il als a9ects the ,a,e" i%s*lati% / the c"e
a%#!i%#i%' / t"a%s/"me". Pa,e" is hi'hly hy'"sc,ic i% %at*"e.
Pa,e"abs"bs ma$im*m am*%t / !ate" /"m il !hich a9ects
,a,e"i%s*lati% ,",e"ty as !ell as "e#*ce# its li/e. B*t i%
la#e#t"a%s/"me"& il becmes htte"& he%ce the sl*bility /
!ate" i% ili%c"eases as a "es*lt the ,a,e" "eleases !ate" a%#
i%c"ease
the water content in transformer oil.
Th*s the tem,e"at*"e / the il at the time / ta8i%' sam,le
/" testis +e"y im,"ta%t. D*"i%' $i#ati% aci# a"e /"me# i% the il
theaci#s 'i+e "ise the sl*bility / !ate" i% the il. Aci# c*,le#
!ith!ate" /*"the" #ecm,se the il /"mi%' m"e aci# a%# !ate".
This"ate / #e'"a#ati% / il i%c"eases. The !ate" c%te%t i% il
ismeas*"e# as ,mHH
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!cidity of Transformer Oil
!cidity of transformer oil, is harmful property. 6f oil
becomes acidic, water content in the oil becomes more
soluble to the the oil. "cidity of oil deteriorates the
insulation
property of paper insulation of winding. "cidity acceleratesthee
o)idation process in the oil.
"cid also includes rusting of iron in presence of
moisture.
he acidity of transformer oil is measure of its acidic
constituents of contaminants. "cidity of oil is e)press in
mg
of =/B required to neutrali0e the acid present in a gram of
oil. his is also !nown as neutrali0ation number.
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%CIDIT& OR !E'TR%LI%TIO! !'()ER*!!+
Aci#s i% the il "i'i%ate /"m il #ecm,siti%$i#ati% ,"#*cts.
Aci#sca% als cme /"m e$te"%al s*"ces s*ch as atms,he"icc%tami%ati%.
These "'a%ic aci#s a"e #et"ime%tal t the i%s*lati%system a%# ca%
i%#*ce c""si% i%si#e the t"a%s/"me" !he% !ate" is,"ese%t.
A% i%c"ease i% the aci#ity is a% i%#icati% / the "ate /
#ete"i"ati% /the il !ith SLUD)E as the i%e+itable by0,"#*ct / a%
aci# sit*ati%!hich is %e'lecte#.
The aci#ity / il i% a t"a%s/"me" sh*l# %e+e" be all!e# t
e$cee#J.6m' ;O(' il. This is the CRITICAL ACID NUMBER a%#
#ete"i"ati%i%c"eases "a,i#ly %ce this le+el is e$cee#
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lash Point of Transformer Oil
lash point of transformer oil is the temperature at which
oilgives enough vapours to produce a flammable mi)ture with
air.
his mi)ture gives momentary flash on application of flame
under standard condition.
Flash point is important because it specifies the chances offire
ha0ard in the transformer. So it is desirable to have very
high flash point of transformer oil. 6n general it is more
than
1;@oD1@o.
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our oint of Transformer Oil
It is the mi%im*m tem,e"at*"e at !hich il *st sta"t t! *%#e"
sta%#a"# test c%#iti%. P*" Pi%t /
T"a%s/"me" Oil is a% im,"ta%t ,",e"ty mai%ly at the,laces
!he"e climate is e$t"emely cl#. I/ the il
tem,e"at*"e /alls bell! the ,*" ,i%t& t"a%s/"me" ilst,s
c%+ecti% !i%' a%# bst"*ct cli%' i%t"a%s/"me".
Pa"a5% base# il has hi'he" +al*e / ,*" ,i%t&
cm,a"e# t Na,htha base# il& b*t i% I%#ia li8ec*%t"y& it
#es %t e9ect the *se / Pa"a5% il #*e tits!a"m climate c%#iti%. P*"
Pi%t / t"a%s/"me" ilmai%ly #e,e%#s *,% !a$ c%te%t i% the il. As
Pa"a5%base# il has m"e !a$ c%te%t& it has hi'he" ,*",i%t.
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INTER4ACIAL TENSION
Meas*"e / mlec*la" att"acti+e /"cebet!ee% thei" *%li8e mlec*les
at thei%te"/ace / il a%# !ate" UNIT %m
Test Meth# > IS: 4J? > 44
The /"ce "e3*i"e# t li/t a ,la%%e" "i%' /,lati%*m /"m the
il0!ate" i%te"/acei%t il is meas*"e#
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I!TER-%CI%L TE!IO!*I-T+
The I%te"/acial Te%si%
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Pla" Im,*"ities a%# IFT al*e
The t"a%s/"me" il #*"i%' hi'he" tem,e"at*"e / ,e"ati%
"eacts !ithatms,he"ic $y'e% a%# the metallic ,a"ts acts as catalyst
th*s
/"mi%'
"'a%ic ,e"$i#es a%# small 3*a%tity / Al#ehy#es a%# ;et%es.
As the $i#ati% ,"cee#s& la"'e" 3*a%tity / "'a%ic aci#s a%#
the"cm,*%#s / ,la" %at*"e a"e "eleases i%t the il.
The te"m Pla" is *se# t #esc"ibe a chemical b%#&
chemical '"*," mlec*les that a"e elect"ically
*%symmet"ical.
2he% a ,la" cm,*%# e$cee# s ce"tai% le+el& ,lyme"i7ati%
ta8es
,lace
These ,lyme"s i%sl*ble i% il a%# hy#",hilic i% %at*"e a"e
calle#SLUD)E.
2he% the c%ce%t"ati% / ,la" im,*"ities s*ch as aci#s&
al#ehy#es
i%c"eases i% the il & the IFT +al*e / il is l!e"e#.
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IFT QUIC; FIELD
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Place a #", / il Oil
s,"ea#s
Place a #",
/Pla"
i%#icat"
? #y%esc
H #y%escm 6#y%escm
6J#y%escm
4#y%escm
IFT QUIC; FIELD TEST
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Chart for rapidlydetermining the acid
content of insulating oils
J.JJ
J.J
J.4J
J.6J
J.HJ
J.?J
J.J
J.J
J.@J
4.JJ
Q*ic8 Fiel# Test /" ACIDITY
Ta8e 4.4ml / t"a%s/"me"t be teste#
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I-T2!! Relationship
St*#ies ha+e sh!% that a #e-%ite "elati%shi, e$ists
bet!ee% aci# %*mbe"
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The ma'%it*#e / the IFT is i%+e"sely "elate# t
thec%ce%t"ati% / the hy#",hilic #e'"a#ati% ,"#*cts /"mthe
#ete"i"ati% / the il. Si%ce the hy#",hilic mate"ialsa"e *s*ally
hi'hly ,la" a%# th*s %t +e"y sl*ble i% the
%%0,la" il& the ,"ese%ce / these s,ecies ca% "es*lt i%sl*#'e
/"mati%. These mate"ials that "emai% #issl+e# i%the il ca% a9ect
the #esi"e# elect"ical ,",e"ties / the il.
They !ill "e#*ce the #ielect"ic st"e%'th a%# i%c"ease
the#issi,ati% /act" / the il.
Sl*#'e b*il#0*, ca% als a9ect the heat t"a%s/e"cha"acte"istics /
the il by sl!i%' " ,e"ha,s e+e%blc8i%' ci"c*lati% / the il. The"e
is *s*ally a% i%+e"se"elati%shi, bet!ee% the %e*t"ali7ati% %*mbe" /
a% ila%# its IFT.
As a% il sam,le *%#e"'es $i#ati+e #e'"a#ati%&
its%e*t"ali7ati% %*mbe" !ill i%c"ease !hile its IFT +al*e
!ill#ec"ease. It sh*l# als be "ec'%i7e# that a #ec"ease i%the IFT
#es %t im,ly that the aci#ity m*st als be hi'h&
si%ce the"e a"e the" %%0aci#ic c%tami%a%ts that c*l#
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QUALITY INDE SYSTEM
Di+i#i%' the I%te"/acial Te%si%
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Ty,ical ,atte"% / i%c"ease i% NNas a /*%cti% / time is
e$hibite#by c*"+e /" t"a%s/"me" il,e"ate# at JC. Thee$,%e%tial "ise
i% NN at thec"itical ,i%t "es*lts /"m thecatalytic acti% / aci#s
a%# the#e,leti% / the $i#ati%i%hibit"s. (eat is the
'"eatestaccele"at" / il #ete"i"ati%#ete"i"ati% is mst ma"8e#ab+e
JC. Bey%# JC& the"ate / #ete"i"ati%
a,,"$imately #*bles /" each4JC i%c"ease.
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O5IDATION STAILITY
(GLASS T6E METHOD&
SI)NIFICANCE:
DEELOPMENT OF ACIDITY G SLUD)E DURIN)STORA)E OF OIL& AND ITS
SERICE LIFE ISMINIMISED IF T(E OIL PASSES T(IS TEST.
T(E QUALITY OF OIL T(EN 2OULD BESUITABLE.
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CORROSIVE S6L3H6R
DETECTION OF SULP(UR COMPUNDS IN OILBY DISCOLOURATION OF
SOPPER SURFACEIN CONTACT 2IT( OIL AT ELEATED TEMPERATURE
MET(OD:
6' OF OIL $ 6mm POLIS(ED C* STRIPBENT J 0 0 0 NITRO)EN BUBBLED
FOR 4 MIN0 0 0 (EATED 4?JK C FOR 4 (OURS
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COLOUR OF COPPER AFTER TEST:
4. O"a%'e "e#& m*lti0cl*"e# 0 0 0 %%0c""si+e6.
Blac8& '"ay " b"!% 0 0 0
c""si+e Ne! i%s*lati%' il is "e3*i"e# t be
%%0c""si+e P"ese%ce / s*l,h*" cm,*%#s i% il 0 0
De'"a#e metal !i%#i%'s i% e3*i,me%ts
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O5IDATIVE AGEING Y O3EN EAKER
METHOD
ANOT(ER MET(OD TO DETERMINE T(EQUALITY OF NE2 INSULATIN) OIL
2IT(
RESPECT TO OIDATIE DE)RADATION
METHOD:
HJJ ml OF OIL 4 S3.cm OF POLIS( COPPER2IT( (EATED AT 44K C FOR
(OURS
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A/te" cli%' the ,",e"ties #ete"mi%e#
al%' !ith the s,eci-e# limits a"e:
I. DDF at JK c 0 J.6
Ii. Resisti+ity JK c 0 J.6 $ 4J
6K c 0 6. $ 4J
Iii. Aci#ity 0 J.J m'
;O( 'I+. Sl*#'e c%te%t 0 J.J V BY !t.
T%)LE 34 %LIC%TIO! %!D I!TERRET%TIO!
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T%)LE 34 %LIC%TIO! %!D I!TERRET%TIO!O- TET O! OIL I!
TR%!-OR(ER
AS PER IS: 4@ > 4@H
Sl.N.
Cha"acte"istic
E3*i,me%t
+lta'e
Pe"missible limit&satis/act"y /"
*se
Acti% i/ *tsi#e,e"missible limit
4S,eci-c"esista%ce atJ c hm0cm&mi%
All+lta'es
J.4 W e46
Rec%#iti% it the+al*e / #ielect"ic#issi,ati% /act",e"mits&
"eclaim i/
%t.
6Dielect"ic#issi,ati%/act" at J c&ma$
4? 8+ 4? 8+
J.64.J
Reclaim
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Sl.N
Cha"acte"isticE3*i,me
%t
+lta'e
Pe"missiblelimit&
satis/act"y /"*se
Acti% i/*tsi#e
,e"missiblelimit
HNe*t"ali7ati%+al*e&m' ;O( '
All+lta'es
J. Reclaim
?P"eci,itatesl*#'e
All+lta'es
N ,e"ce,tiblesl*#'e
Reclaim
Flash ,i%tAll
+lta'es
Dec"ease i%
ash ,i%t 4c
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Sl.N
Cha"acte"isticE3*i,me%t
+lta'e
Pe"missible limit&satis/act"y /"
*se
Acti% i/ *tsi#e,e"missible limit
I%te"/acialte%si% at6c& %m&mi%
All +lta'es J.J4 Reclaim.
Elect"icst"e%'th
4? 8+ ab+e
4? 8+ 6. 8+
6. 8+
J8+ mi%?J 8+ mi%?J 8+ mi%HJ 8+ mi%
Rec%#iti%Rec%#iti%Rec%#iti%Rec%#iti%
@2ate" c%te%t,,m
4? 8+ 4? 8+
6 ,,mH ,,m
Rec%#iti%Rec%#iti%
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LIMITING VAL6ES IS7 89:: ; 8
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ACIDITY m' ;O( '& Ma$
ALL OLTA)E IS: 4?? J.
IFT& Nm. Mi% ALL OLTA)E IS: 4J? J.J4
FLAS( POINT De'C& Mi%
ALL OLTA)EIS: 4??@
Ma$ Dec 446
SEDIMENT AND OR PRECIPITABLESLUD)E
ALL OLTA)E IS: 4 NIL
4OR TRANS4ORMERS IN SERVICE
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P",e"ties C%#iti% Reme#ies
B"ea8#!%+lta'e
L!Filt"ati% *%#e" +ac**m tem,e"at*"e
Mist*"e (i'h
Dielect"ic#issi,ati% /act"
(i'h
Filt"ati% as ab+e i/ theca*se is mist*"e " the"
l*me"esisti+ity
L!
IFT L! Reclamati%
)ENERAL
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N (I)(
FP LO2INESTI)ATE T(ECAUSE
SLUD)E V (I)( DE0SLUD)IN)
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S6GGESTED LIMITS 4OR IN SERVICE OILS GRO63 I YVOLTAGE CLASS1
ASED ON IS7 89::>8
