Post on 24-Feb-2018
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TESTING OF SWITCHGEAR
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SWITCH GEARSWITCH GEAR
Circuit BreakerCircuit Breaker
Busbars and associated Insulators.Busbars and associated Insulators.
Isolators/ isconnectorsIsolators/ isconnectors Instru!ent Trans"or!ersInstru!ent Trans"or!ers
#rotecti$e Rela%s and au&iliar% circuits#rotecti$e Rela%s and au&iliar% circuits
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SWITCHGEAR TESTINGSWITCHGEAR TESTING
e$elo'!ental Teste$elo'!ental Test
T%'e TestT%'e Test
Routine TestRoutine Test Factor% Ins'ection TestFactor% Ins'ection Test
#re(Co!!issionin) Test#re(Co!!issionin) Test
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Developemental TestDevelopemental Test
Carried out on components,sub-assembliesCarried out on components,sub-assemblies
and complete switc!ear durin! and a"terand complete switc!ear durin! and a"ter
te development o" switc!ear#te development o" switc!ear#
Related wit R$Ds and manu"acturin!Related wit R$Ds and manu"acturin!
processes#processes#
%ot covered under an& re"erence standard#%ot covered under an& re"erence standard#
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T&pe TestT&pe Test
Tese tests are carried out "or te purposeTese tests are carried out "or te purpose
o" provin! caracteristics o" switc!ear ando" provin! caracteristics o" switc!ear and
control !ear, teir operatin! devices andcontrol !ear, teir operatin! devices and
au'iliar& e(uipment#au'iliar& e(uipment#
Te t&pe tests are carried out on aTe t&pe tests are carried out on a
ma'imum o" "our test specimen unlessma'imum o" "our test specimen unless
oterwise speci"ied in te relevant IECoterwise speci"ied in te relevant IEC
standards#standards#
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T%'e TestT
%'e Test
*i)+tnin) I!'ulse Test*i)+tnin) I!'ulse Test
S,itc+in) I!'ulse TestS,itc+in) I!'ulse Test
#o,er Fre-uenc% O$er olta)e Wit+stand Test#o,er Fre-uenc% O$er olta)e Wit+stand Test
#artial isc+ar)e Test#artial isc+ar)e Test Arti"icial #ollution TestArti"icial #ollution Test
Te!'erature Rise TestTe!'erature Rise Test
Resistance easure!ent o" t+e ain Circuit.Resistance easure!ent o" t+e ain Circuit.
S+ort Ti!e Wit+stand Current Test0 #eak Wit+standS+ort Ti!e Wit+stand Current Test0 #eak Wit+standCurrent TestCurrent Test
akin) Current and Breakin) Current Testakin) Current and Breakin) Current Test
ec+anical Endurance Testec+anical Endurance Test
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*i)+tnin) I!'ulse Test*i)+tnin) I!'ulse Test
Te insulation o" switc!ear sould be soTe insulation o" switc!ear sould be sodesi!ned tat it can witstand te occasionaldesi!ned tat it can witstand te occasional)i!tnin! sur!es o" i! pea* value, sarp rate o")i!tnin! sur!es o" i! pea* value, sarp rate o"
rise and sort duration#rise and sort duration# Te li!tnin! impulse volta!e witstand level o"Te li!tnin! impulse volta!e witstand level o"
te switc!ear is proved b& conductin! tis test#te switc!ear is proved b& conductin! tis test#
Te test is per"ormed wit volta!es o" botTe test is per"ormed wit volta!es o" bot
positive and ne!ative polarit& wit respect topositive and ne!ative polarit& wit respect toeart usin! te standard )i!tnin! Impulseeart usin! te standard )i!tnin! Impulse+#./+#./0s wave"orm 12i! +3#0s wave"orm 12i! +3#
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*i)+tnin) I!'ulse Test*i)+tnin) I!'ulse Test
Rated olta)e 12r!s3Rated *i)+tnin) I!'ulse Test
olta)e 12'eak3
4.5 67
8.9 57
:9.7 8;
45.7 :87
:6;.7 5;7
96;.7 :7;7
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Brie" test 'rocedure
Te standard test involves te application o" +. nos# o" test
volta!es1+#./microsec li!tnin! impulse wave sur!e to
simulate li!tnin! stro*e condition3 between eac pase and
eart in turn wit C4 closed $ oter pases earted# Inaddition, test volta!es are also applied across eac set o" open
C4 contacts# Te overall test is considered to be satis"actor& i"
not more tan "lasovers occur durin! an& series o" +. tests
provided tat tese discar!es onl& occur in sel"-restorin!insulation 1i#e# air, oil or S25 !as3# A brea*down o" solid
insulation normall& results in an inabilit& to recover and
constitutes a test "ailure#
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BASIC CIRC
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Switcin! Impulse TestSwitcin! Impulse Test
Te purpose o" tis test is to veri"& teTe purpose o" tis test is to veri"& teabilit& o" te insulation o" switc!ear toabilit& o" te insulation o" switc!ear towitstand te occasional i! "re(uenc&witstand te occasional i! "re(uenc&
Switcin! sur!es occurred durin! openin!Switcin! sur!es occurred durin! openin!$ closin! o" unloaded EH6 AC lines,$ closin! o" unloaded EH6 AC lines,switcin! o" small inductive or capacitiveswitcin! o" small inductive or capacitive
loads etc#loads etc#
Tis test is necessar& "or switc!ear o"Tis test is necessar& "or switc!ear o"ratin! 7// 86 and above#ratin! 7// 86 and above#
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Te switcin! sur!es are simulated in testTe switcin! sur!es are simulated in test
laboratories b& a representative ./.// 0slaboratories b& a representative ./.// 0s
switcin! impulse wave obtained "rom answitcin! impulse wave obtained "rom an
impulse !enerator#impulse !enerator#
Te test procedure o" switcin! impulse isTe test procedure o" switcin! impulse is
same as tat o" )i!tnin! Impulse Test#same as tat o" )i!tnin! Impulse Test#
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9ower 2re(uenc& :ver volta!e9ower 2re(uenc& :ver volta!e
Witstand TestWitstand Test Te purpose o" tis test is to veri"& teTe purpose o" tis test is to veri"& te
abilit& o" te insulation o" switc!ear toabilit& o" te insulation o" switc!ear to
witstand te temporar& power "re(uenc&witstand te temporar& power "re(uenc&
over vota!es "or a speci"ied sort duration#over vota!es "or a speci"ied sort duration#
Tese over volta!es o" ./H; wave"orm areTese over volta!es o" ./H; wave"orm are
produced b& sudden load-trow-o"", "aults,produced b& sudden load-trow-o"", "aults,
resonance, and poor volta!e re!ulations b&resonance, and poor volta!e re!ulations b&
:)TC o" trans"ormers etc#:)TC o" trans"ormers etc#
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Test 'rocedureTest 'rocedure
Main CircuitMain Circuit
Te switc!ear is sub
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Rated olta)e 12r.!.s3Rated #o,er Fre-uenc%
Test olta)e 12r!s3
4.5 :7
8.9 97
:9.7 9=
45.7 87
:6;.7 98;
96;.7 ;47
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On Auxiliary & Control CircuitsOn Auxiliary & Control Circuits
Au'iliar& and control circuits o" switc!ear sall beAu'iliar& and control circuits o" switc!ear sall besub
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9artial Discar!e Test9artial Discar!e Test
Te primar& reason o" tis test is to cec* teTe primar& reason o" tis test is to cec* teealtiness o" insulation o" switc!ear #ealtiness o" insulation o" switc!ear #
>ain cause o" 9D is te "ormation o" localised void in>ain cause o" 9D is te "ormation o" localised void inte insulation#te insulation#
Te applied power "re(uenc& volta!e is raised to a pre-Te applied power "re(uenc& volta!e is raised to a pre-stress value wic is identical to te power "re(uenc&stress value wic is identical to te power "re(uenc&witstand volta!e test and maintained at tat value "or +witstand volta!e test and maintained at tat value "or +min# 9artial discar!e occurrin! durin! tis period ismin# 9artial discar!e occurrin! durin! tis period is
disre!arded# Ten te volta!e is decreased to a speci"icdisre!arded# Ten te volta!e is decreased to a speci"icvalue de"ined in te table below dependin! upon tevalue de"ined in te table below dependin! upon tecon"i!uration o" e(uipment and s&stem neutral "orcon"i!uration o" e(uipment and s&stem neutral "or
partial discar!e measurement#partial discar!e measurement#
T i i iblT i i ibl
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Te ma'imum permissibleTe ma'imum permissible
partial discar!e level sallpartial discar!e level sall
not e'ceed . pC#not e'ceed . pC#
However some e(uipment inHowever some e(uipment insw# !ear li*e 6olta!esw# !ear li*e 6olta!e
Trans"ormer ave anTrans"ormer ave an
acceptable level o" 9D !reateracceptable level o" 9D !reater
tan . pC#tan . pC#
An& sub-assembl&An& sub-assembl&
containin! suc componentscontainin! suc components
sall be considered acceptablesall be considered acceptablei" te discar!e level does noti" te discar!e level does not
e'ceed +/ pc, but in tat casee'ceed +/ pc, but in tat case
tese will be tested "or 9Dtese will be tested "or 9D
separatelseparatel
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Arti"icial 9ollution TestArti"icial 9ollution Test
Tese tests are intended to provide in"ormation on te beaviour o"Tese tests are intended to provide in"ormation on te beaviour o"
e'ternal insulations under conditions representative o" pollution ine'ternal insulations under conditions representative o" pollution in
service#service#
%o arti"icial pollution tests are necessar& wen te creepa!e distances%o arti"icial pollution tests are necessar& wen te creepa!e distanceso" te insulators compl& wit te relationsip !iven below ?o" te insulators compl& wit te relationsip !iven below ?
It @ a ' I" ' r ' 8DIt @ a ' I" ' r ' 8D
Were, It @ minimum nomianl creepa!e distance in mmWere, It @ minimum nomianl creepa!e distance in mm
a @ application "actora @ application "actor
I" @ minimum nominal speci"ic creepa!e distance 1mm*63I" @ minimum nominal speci"ic creepa!e distance 1mm*63
r @ Rated volta!e o" switc!ear in 86r @ Rated volta!e o" switc!ear in 86
8D@ Correction "actor due to diameter8D@ Correction "actor due to diameter
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Temperature Rise TestTemperature Rise Test
Temperature rise test is performedto prove that temperature risecomply to limits specied instandards and to derive thermalcharacteristic of the transformer.
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Temperature Rise TestTemperature Rise Test
Te test is done wit te normal ratedTe test is done wit te normal ratedsinusoidal current wit te tree polessinusoidal current wit te tree polesconnected in series# Temperature rise test isconnected in series# Temperature rise test is
carried out over a period o" time su""icientcarried out over a period o" time su""icient"or te temperature rise to reac a constant"or te temperature rise to reac a constantvalue#Wen te stead& temperature isvalue#Wen te stead& temperature isreaced te ma'imum temperature rise o"reaced te ma'imum temperature rise o"eac part sould be less tan teeac part sould be less tan tepermissible limits as per IS#permissible limits as per IS#
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Resistance measurementResistance measurement
o" >ain Circuito" >ain Circuit >easurement o" resistance o" >ain Circuit>easurement o" resistance o" >ain Circuit
is made "or comparison between Sw# Gearis made "or comparison between Sw# Gear
t&pe tested "or temperature rise and sw#t&pe tested "or temperature rise and sw#
!ears o" te same t&pe#!ears o" te same t&pe#
Te resistance is measured be"ore and a"terTe resistance is measured be"ore and a"ter
temperature rise test and te readin!s intemperature rise test and te readin!s in
tese two conditions sould not di""er b&tese two conditions sould not di""er b&
more tan /B#more tan /B#
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Te resistance is measured b& >illivoltTe resistance is measured b& >illivolt
Drop Test >etod#Drop Test >etod#
Te DC current sould be more tan ./ATe DC current sould be more tan ./Aand less tan rated current o" circuitand less tan rated current o" circuit
brea*er#brea*er#
Te resistance sould be measured atTe resistance sould be measured at
ambient air temperature#ambient air temperature#
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Resistance measurementResistance measurement
o" Au'illiar& Circuito" Au'illiar& Circuit Tese test is intended to veri"& te contact per"ormanceTese test is intended to veri"& te contact per"ormance
under e'tremel& low volta!e condition due to teunder e'tremel& low volta!e condition due to tereason tat on au'illiar& contact materials, o'idationreason tat on au'illiar& contact materials, o'idationma& occur wic results in an increased contactma& occur wic results in an increased contact
resistance or even no conduction at ver& low volta!e#resistance or even no conduction at ver& low volta!e# :ne sample o" eac t&pe o" au'illiar& contacts is:ne sample o" eac t&pe o" au'illiar& contacts is
inserted into a resistive load circuit trou! wicinserted into a resistive load circuit trou! wic"lows a current o" +/ mA wen ener!ised b& a source"lows a current o" +/ mA wen ener!ised b& a source
avin! an open circuit volta!e o" 5 6 DC wit aavin! an open circuit volta!e o" 5 6 DC wit arelative tolerence o" /-+.B and te resistance isrelative tolerence o" /-+.B and te resistance ismeasured accordin! to IEC 5/.+-#measured accordin! to IEC 5/.+-#
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Rated Sort Time WitstandRated Sort Time Witstand
Current TestCurrent Test De"De"nn ?Te r#m#s value o" te current wic?Te r#m#s value o" te current wic
te switc!ear can carr& in te closedte switc!ear can carr& in te closed
position durin! a speci"ied sort time#position durin! a speci"ied sort time#
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Routine TestRoutine Test
Ti)+tness testTi)+tness test
easure!ent o" resistance o" !aineasure!ent o" resistance o" !ain
circuit o" eac+ 'olecircuit o" eac+ 'ole
#o,er "re-uenc% $olta)e ,it+stand test#o,er "re-uenc% $olta)e ,it+stand test
on !ain circuit and au&iliar% circuitson !ain circuit and au&iliar% circuits
ec+anical o'eratin) testec+anical o'eratin) test
esi)n and $isual c+ecksesi)n and $isual c+ecks
Tests on au&iliar% and control circuitsTests on au&iliar% and control circuits
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Ti!tness TestTi!tness Test
Te purpose o" ti!tness tests is to demonstrateTe purpose o" ti!tness tests is to demonstrate
tat te absolute lea*a!e rate does not e'ceed tetat te absolute lea*a!e rate does not e'ceed te
speci"ied value o" te permissible lea*a!e rate#speci"ied value o" te permissible lea*a!e rate#
Te test sall be per"ormed at normal ambient airTe test sall be per"ormed at normal ambient air
temperature wit te assembl& "illed at tetemperature wit te assembl& "illed at te
pressure 1or densit&3 correspondin! topressure 1or densit&3 correspondin! to
manu"acturers test practice#manu"acturers test practice#
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ec+anical o'eratin) test
>ecanical operational tests are per"ormed on switc!ear at te"ollowin! points?
1a3 at speci"ied ma'# suppl& volta!es and !as pressure1i"
applicable3
+# "ive closin! operations# "ive openin! operations
1b3 at speci"ied min# suppl& volta!es and !as pressure1i"
applicable3
+# "ive closin! operations
# "ive openin! operations1c3 at speci"ied rated suppl& volta!es and !as pressure1i"
applicable3
+# "ive closin! operations
# "ive openin! operations
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Desi!n and 6isual Cec*Desi!n and 6isual Cec*
Te switc!ear and control !ear sall beTe switc!ear and control !ear sall be
cec*ed to veri"& its compliance wit tecec*ed to veri"& its compliance wit te
purcase speci"ication#purcase speci"ication#
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Tests on Au'iliar& and Control CircuitsTests on Au'iliar& and Control Circuits
Te tests includes ?Te tests includes ?
1i3 Inspection o" au'iliar& and control circuits1i3 Inspection o" au'iliar& and control circuits
Te nature o" te materials, te (ualit& o" assembl&, teTe nature o" te materials, te (ualit& o" assembl&, te
"inis etc# sall be cec*ed# Te components "or au'iliar&"inis etc# sall be cec*ed# Te components "or au'iliar&
circuits inside enclosures sall be cec*ed "or propercircuits inside enclosures sall be cec*ed "or proper
mountin!#mountin!#
##
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1ii3 2unctional tests1ii3 2unctional tests
Tis test is necessar& to veri"& proper "unctionin! o"Tis test is necessar& to veri"& proper "unctionin! o"au'iliar& and control circuits in con
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Factor% Ins'ection Test b% ClientFactor% Ins'ection Test b% Client
Durin! inspection at te manu"acturin!Durin! inspection at te manu"acturin!
wor*s, sample tests are witnessed b& client #wor*s, sample tests are witnessed b& client #
Te normal routine tests are conducted onTe normal routine tests are conducted on
sample switc!ear# Additionall&, client ma&sample switc!ear# Additionall&, client ma&
as* "or oter tests also as per teiras* "or oter tests also as per teir
re(uirement or te& can as* "or repeat testre(uirement or te& can as* "or repeat test
on same switc!earon same switc!ear
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#re Co!!issionin) Test#re Co!!issionin) Test
Hi)+ $olta)e ,it+stand test 1HAC3Hi)+ $olta)e ,it+stand test 1HAC3 Resistance !easure!ent testResistance !easure!ent test
easure!ent o" insulation resistanceeasure!ent o" insulation resistance
o"o"
t+e au&iliar% and control circuitt+e au&iliar% and control circuit Current Trans"or!ers 1 all testsCurrent Trans"or!ers 1 all tests3#3#
olta)e Trans"or!ers 1 all tests 3.olta)e Trans"or!ers 1 all tests 3.
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Current Trans"ormer TestCurrent Trans"ormer Test
IR !easure!ent.IR !easure!ent.
Ratio C+eckin).Ratio C+eckin). Windin) resistance !easure!ent.Windin) resistance !easure!ent.
#olarit% Test#olarit% Test##
a)neti>in) C+aracteristic Testsa)neti>in) C+aracteristic Tests##
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Insulation ResistanceInsulation Resistance
>easurement>easurement
Insulation resistance o" te CT secondar& isInsulation resistance o" te CT secondar& is
measured wit te elp o" +///6measured wit te elp o" +///6
>e!!er 1Insulation Tester3 wit respect to>e!!er 1Insulation Tester3 wit respect to
Eart $ in between di""erent cores#Eart $ in between di""erent cores#
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Ratio Cec*in!Ratio Cec*in!
Te usual metod is to appl& test current toTe usual metod is to appl& test current to
te primar& windin! o" CT close to ratedte primar& windin! o" CT close to rated
primar& current and measure teprimar& current and measure te
ma!nitudes o" primar& and secondar&ma!nitudes o" primar& and secondar&
currents wit a low value o" secondar¤ts wit a low value o" secondar&
burden#burden#
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Ratio Cec*Ratio Cec*1Connection Dia!ram31Connection Dia!ram3
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Windin! ResistanceWindin! Resistance
>easurement>easurement Secondar& windin! resistance o" a CT isSecondar& windin! resistance o" a CT is
measured as per te circuit dia!ram !ivenmeasured as per te circuit dia!ram !iven
below#below#
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9olarit& Testin!9olarit& Testin!
I" at an& instant, current is enterin! teI" at an& instant, current is enterin! te
primar& "rom 9+ te current sould leaveprimar& "rom 9+ te current sould leave
secondar& "rom terminal mar*ed S+# A setsecondar& "rom terminal mar*ed S+# A set
up sown in te "i!ure tests weater teup sown in te "i!ure tests weater te
polarit& mar*in!s wit respect to tepolarit& mar*in!s wit respect to te
secondar& are correct or not# 19+ souldsecondar& are correct or not# 19+ sould
correspond to S+3correspond to S+3
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#olarit% Test#olarit% Test
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>a!neti;in! Caracteristic Test>a!neti;in! Caracteristic Test
>a!neti;in! current is measured "or several secondar&>a!neti;in! current is measured "or several secondar&em"s# Tis is accomplised b& appl&in! appropriateem"s# Tis is accomplised b& appl&in! appropriatevolta!e to te secondar& windin!, and measurin! tevolta!e to te secondar& windin!, and measurin! tecurrent ta*en b& secondar& windin! under test#current ta*en b& secondar& windin! under test#
Durin! te test te primar& and oter windin!s areDurin! te test te primar& and oter windin!s are*ept open circuited#*ept open circuited#
Te R>S value o" te sinusoidal volta!e o" ratedTe R>S value o" te sinusoidal volta!e o" rated"re(uenc& applied to te secondar& windin! wic,"re(uenc& applied to te secondar& windin! wic,
wen increased b& +/B, causes te secondar&wen increased b& +/B, causes te secondar&ma!neti;in! current to increase b& ./B is called 8neema!neti;in! current to increase b& ./B is called 8nee9oint 6olta!e 16*3#9oint 6olta!e 16*3#
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a)neti>in) C+aracteristic Testsa)neti>in) C+aracteristic Tests
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olta)e Trans"or!ersolta)e Trans"or!ers
easure!ent o" IReasure!ent o" IR
Ratio TestRatio Test
#olarit% Test#olarit% Test
easure!ent o" secondar% ,indin) resistanceeasure!ent o" secondar% ,indin) resistance
easure!ent o" 'ri!ar% ,indin) resistanceeasure!ent o" 'ri!ar% ,indin) resistance
a)neti>in) C+aracteristicsa)neti>in) C+aracteristics? O$er olta)e? O$er olta)e
Wit+stand TestWit+stand Test
l i iI l i R i
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Insulation ResistanceInsulation Resistance
>easurement>easurement
>easurement is done wit a +///6 >e!!er to
ascertain te insulation resistance o" primar&
windin! w#r#t eart isolatin! te intentionaleartin!, insulation resistance o" secondar&
windin!s w#r#t eart and insulation resistance in
between primar& and secondar& windin!#
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Ratio TestRatio Test
Te ratio o" 6T is cec*ed b& appl&in! variableTe ratio o" 6T is cec*ed b& appl&in! variable
AC volta!e to te secondar& windin! andAC volta!e to te secondar& windin! and
measurin! its volta!e re"lection in te primarmeasurin! its volta!e re"lection in te primar
Ratio TestRatio Test
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Ratio TestRatio Test
1Back to Back connection o" t,o Ts31Back to Back connection o" t,o Ts3
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#olarit% Test#olarit% Test
easure!ent o" secondar%easure!ent o" secondar
%
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easure!ent o" secondar%easure!ent o" secondar%
Windin) ResistanceWindin) Resistance
easure!ent o" 'ri!ar%easure!ent o"
'ri!ar%
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easure!ent o" 'ri!ar%easure!ent o" 'ri!ar%
Windin) ResistanceWindin) Resistance
a)neti>in) C+aracteristicsa
)neti>in) C+aracteristics ??
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a)neti>in) C+aracteristicsa)neti>in) C+aracteristics??
O$er olta)e Wit+stand TestO$er olta)e Wit+stand Test
>a!neti;in! caracteristic !ives a clear picture o">a!neti;in! caracteristic !ives a clear picture o"amount o" ma!neti;in! current drawn b& secondar&amount o" ma!neti;in! current drawn b& secondar&core and te secondar& e#m#" up to wic te corecore and te secondar& e#m#" up to wic te coree'ibits its ma!netic properties#e'ibits its ma!netic properties#
Te var&in! volta!e is applied in te secondar& o"Te var&in! volta!e is applied in te secondar& o"6T *eepin! te primar& windin! open and is raised6T *eepin! te primar& windin! open and is raisedupto +/B o" te normal rated volta!e 1i#e# +/B o"upto +/B o" te normal rated volta!e 1i#e# +/B o"57#. 63 to ascertain tat 6T can witstand tis57#. 63 to ascertain tat 6T can witstand tis
overvolta!e witout an& "ailure#overvolta!e witout an& "ailure# Te ma!neti;in! current drawn b& te 6T secondar&Te ma!neti;in! current drawn b& te 6T secondar&
core is also noted "or di""erent applied volta!es#core is also noted "or di""erent applied volta!es#
a)neti>in) C+aracteristicsa
)neti>in) C+aracteristics ??
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a)neti>in) C+aracteristicsa)neti>in) C+aracteristics??
O$er olta)e Wit+stand TestO$er olta)e Wit+stand Test
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Fuestions Fuestions
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Tan* ou#Tan* ou#