Case Studies Task Force IEEE C Workgroup Meeting Milwaukee, WI

LIGHTNING STRIKE DGA Results (PPM)Post LightningRoutine Oxygen ( O 2 )7,4914,642 Nitrogen ( N 2 )86,41960,903 Carbon Monoxide (CO) Carbon Dioxide (CO 2 )7,3043,540 DGA Results (PPM)Post LightningRoutine Hydrogen ( H 2 )2,60415 Methane (CH 4 )5169 Ethylene (C 2 H 4 )1,14762 Ethane ( C 2 H 6 )935 Acetylene (C 2 H 2 )2,0610 Roger’s Ratio and IEC Methods Post-Failure R1 CH 4 /H 2 IEC Term 20.2 R2 C 2 H 6 / CH R3 C 2 H 4 /C 2 H 6 IEC Term R4 C 2 H 2 /C 2 H 4 IEC Term 11.8 Roger’s Ratio Table 20,0,2,1 Arcing IEC Ratio Table 3D2 High energy discharge Other Important Ratios O 2 /( O 2+ N 2 )0.08 CO 2 /CO9.25 Duval Triangle Method (Table 5) Post-Lightning % CH % %C 2 H % %C 2 H % CodeD2

SAGGING GROUND STRAP DGA Results (PPM)Post MovePre-move Hydrogen ( H 2 )7045 Oxygen ( O 2 )6,0312,865 Nitrogen ( N 2 ) ,652 Methane (CH 4 )13956 Carbon Monoxide (CO) Carbon Dioxide (CO 2 )3,7913,747 Ethylene (C 2 H 4 )15967 Ethane ( C 2 H 6 )8071 Acetylene (C 2 H 2 )1490 Total Combustible Gas DGA Results (PPM)Post MovePre-move Oxygen ( O 2 )6,0312,865 Nitrogen ( N 2 ) ,652 Carbon Monoxide (CO) Carbon Dioxide (CO 2 )3,7913,747 DGA Results (PPM)Post MovePre-move Hydrogen ( H 2 )7045 Methane (CH 4 )13956 Ethylene (C 2 H 4 )15967 Ethane ( C 2 H 6 )8071 Acetylene (C 2 H 2 )1490 Total Combustible Gas Duval Triangle Method Post-Failure % CH % %C 2 H % %C 2 H % CodeD2 Roger’s Ratio and IEC Methods` Post-Failure R1 CH 4 /H 2 IEC Term R2 C 2 H 6 / CH R3 C 2 H 4 /C 2 H 6 IEC Term R4 C 2 H 2 /C 2 H 4 IEC Term Roger’s Ratio Table 2(1,0,1,1) Close Fix to Arcing IEC Ratio Table 3Loose Fit to D2 Other Important Ratios O 2 /( O 2+ N 2 )0.06 CO 2 /CO29

TURN TO TURN WINDING FAULT DGA Results (PPM)Post-FailurePre-Failure Hydrogen ( H 2 )1220 Oxygen ( O 2 ) Nitrogen ( N 2 ) Methane (CH 4 )01 Carbon Monoxide (CO)35517 Carbon Dioxide (CO 2 ) Ethylene (C 2 H 4 )2410 Ethane ( C 2 H 6 )39 Acetylene (C 2 H 2 )1000 Total Combustible Gas60437 DGA Results (PPM)Post-FailurePre-Failure Oxygen ( O 2 )4,2474,372 Nitrogen ( N 2 )87,95288,540 Carbon Monoxide (CO) Carbon Dioxide (CO 2 )6,3306,684 DGA Results (PPM)Post-FailurePre-Failure Hydrogen ( H 2 )1220 Methane (CH 4 )01 Ethylene (C 2 H 4 )2410 Ethane ( C 2 H 6 )39 Acetylene (C 2 H 2 )1000 Total Combustible Gas Duval Triangle Method Post-Failure % CH % %C 2 H % %C 2 H % CodeD1 Roger's Ratios Method Post-Failure R1 CH 4 /H 2 IEC Term 20 R2 C 2 H 6 / CH 4 0 R3 C 2 H 4 /C 2 H 6 IEC Term 38 R4 C 2 H 2 /C 2 H 4 IEC Term 14.2 Roger’s Diagnostic Table 2 5,0,2,2 close fit to Arcing IEC Ratios Table 3D1 Other Important Ratios O 2 /N CO 2 /CO6.4

DETC TAP CHANGER FAULT Sample Date11/22/20027/31/20021/14/200211/21/20015/14/2001 Hydrogen (H 2 ) Methane (CH 4 )4,2641, Carbon Monoxide (CO) Carbon Dioxide (CO 2 )1, Ethylene (C 2 H 4 )4,3921, Ethane (C 2 H 6 )1, Acetylene (C 2 H 2 )30000 Combustible Gas11,6594,2362,1952, Sample Date11/22/027/31/021/14/0211/21/015/14/01 Hydrogen (H 2 ) Methane (CH 4 )4,2641, Ethylene (C 2 H 4 ) 4,3921, Ethane (C 2 H 6 )1, Acetylene (C 2 H 2 ) PPM/Day11/22/027/31/021/14/0211/21/01 H2H CH C2H4C2H C2H6C2H C2H2C2H2 0.0 Comb. Gas Ratios 11/22/200 27/31/20021/14/200211/21/2001 R1 CH 4 /H 2 IEC Term R2 C 2 H 6 / CH R3 C 2 H 4 /C 2 H 6 IEC Term R4 C 2 H 2 /C 2 H 4 IEC Term Roger’s Diagnostic Table 22/0/1/0 IEC Ratios Table 3T2 O 2 /( O 2+ N 2 ) CO 2 / CO Duval Triangle Method ( See Table 4 and 5) Ratios11/22/20027/31/20021/14/200211/21/2001 % CH %52.20%43.20%53.00% %C 2 H %47.80%56.80%47.00% %C 2 H % Diagnostic Code (Table 5)T3T2T3T2

UNINTENTIONAL CORE GROUND FAULT Sample Date7/9/20015/30/20013/31/2000 Hydrogen (H 2 ) Oxygen (O 2 )4,8191,94523,566 Nitrogen (N 2 )90,23278,96188,681 Methane (CH 4 )001 Carbon Monoxide (CO)3,3952, Carbon Dioxide (CO 2 ) Ethylene (C 2 H 4 )5,6735,4150 Ethane (C 2 H 6 )1, Acetylene (C 2 H 2 )500 Total Combustible Gas10,9339, Roger’s and IEC Ratio Methods (Table 1, 2 & 3) Sample Dates7/9/20015/30/2001 R1 CH 4 /H 2 IEC Term 200 R2 C 2 H 6 / CH 4 00 R3 C 2 H 4 /C 2 H 6 IEC Term 35.6 R4 C 2 H 2 /C 2 H 4 IEC Term 1 00 Roger’s Ratio5,0,2,0 IECNo fit Other Important Ratios O 2 /( O 2+ N 2 ) CO 2 /CO Duval Triangle Method (Table 4 and 5) Sample Date07/09/0105/30/0103/31/00 % CH 4 0.0% 100.0% %C 2 H %100.0%0.0% %C 2 H 2 0.1%0.0% Diagnostic Code (Table 5) T3 Region, Thermal Fault, T >700 °C

HIGH VOLTAGE PHASE TO GROUND Sample Date2/16/20042/13/2004 Hydrogen ( H 2 )9013 Oxygen (O 2 )34,78425,811 Nitrogen (N 2 )114,213101,010 Methane (CH 4 )485 Carbon Monoxide (CO) Carbon Dioxide (CO 2 ) Ethylene ( C 2 H 4 )1133 Ethane (C 2 H 6 )52 Acetylene (C 2 H 2 )3540 Combustible Gas Roger’s and IEC Ratio Methods Ratios R1 CH 4 /H 2 IEC Term R2 C 2 H 6 / CH R3 C 2 H 4 /C 2 H 6 IEC Term R4 C 2 H 2 /C 2 H 4 IEC Term Diagnostic Case 2 (Table 2) (0,0,2,2) Arcing IEC Ratio (Table 3)D1 Other Important Ratios O 2 /( O 2 +N 2 )0.23 CO 2 /CO4.13 Duval Triangle Method (Table 2) Ratios2/16/04 % CH 4 9.3% %C 2 H % %C 2 H % Diagnostic Code (Table 5) D2

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