Liquid Dielectric Test Tables Task Force (C57.12.00) Rev 17 Porto, Portugal October 7, 2008 PJH Charlotte, NC March 18, 2008 1 Liquid Dielectric Test Tables Task Force (C57.12.00) AGENDA 1. Introductions 2. Mission & Scope 3. Minutes & Review from March Charlotte Meeting 4. Document Status A. Present Form B. C57.12.00R with proposed Text revisions 6. Future Considerations: Propose disbanding Taskforce 7. Discussion and Adjournment PJH Charlotte, NC March 18, 2008 2 Liquid Dielectric Test Tables Task Force (C57.12.00) PJH Charlotte, NC March 18, 2008 3 Liquid Dielectric Test Tables Task Force (C57.12.00) Mission & Scope • Clean Up Inconsistencies • Harmonize with IEC 76-3 • Provide Reference Considerations • Simplify Tables PJH Charlotte, NC March 18, 2008 4 IEEE C57.12.00/12.01/IEC 76-3 Dielectric Test Tables Survey Tally Number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 Person Last Name Mcnelly Kraetge Molden Poulin Patel Britton Garner Harley Henning Guardado Corkran Graham Foldi Matthews Thierry Miller Sampat Riffon Recksiedler Riboud Hayes Tuli Wagenaar Boettger Hopkinson Choinski Perkins Forsyth Kim Snyder Garcia Davis Frimpong Preininger Elliott Platts PJH Charlotte, NC March 18, 2008 Approve First Name Sue Alexander Art Bertrand Bipin Jeffrey Charles Jack Bill Jeremy Jerry Jim Joe John Juan Kent Mahesh Pierre Leslie Jean-Christoff Roger Subhash Loren William Phil Scott Mark Bruce Dong Steve Eduardo Eric George Gustav Fred Don Approve with Comments 3 Abstain Disapprove with comments 1 3 1 4 1 1 1 1 1 1 1 3 1 1 1 1 7 1 2 1 5 1 1 1 1 3 1 1 10 1 5 1 1 1 1 15 29 3 24 Date Comment Type ED Tech 1/2/2008 3 1/25/2008 1/28/2008 3 1/3/2008 1/9/2008 4 1/2/2008 1/29/2008 1/2/2008 1/24/2008 1 1/3/2008 1/14/2008 1 1/9/2008 1/14/2008 2 1 1/24/2008 1/28/2008 1/2/2008 1/3/2008 1 1/24/2008 4 3 1/2/2008 1/2/2008 2 1/24/2008 1 1/9/2008 2 3 1/24/2008 1 1/29/2008 1/30/2008 1/30/2008 1/30/2008 3 1/30/2008 1 1/31/2008 1/31/2008 6 4 1/31/2008 1/31/2008 5 1/31/2008 1/13/2008 1 2/1/2008 2/6/2008 32 20 5 IEEE C57.12.00/12.01/IEC 76-3 Dielectric Test Tables: •New Proposed C57.12.00 Sections 5.5-5.10 •Comments and Proposed Disposition PJH Charlotte, NC March 18, 2008 6 Table 4: Distribution and Class I Transformers, voltages in kV Max Sytem Voltage Nominal System Voltage Col 1 Col 2 Applied Test Delta & Fully Gr Y Impedance Insulated Gr Y Col 3 1.5 3.5 6.9 11 17 26 36 48 73 1.2 2.5 5 8.7 15 25 34.5 46 69 10 15 19 26 34 40 50 95 140 1.5 3.5 6.9 11 17 26 36 48 73 Notes: 1 1.2 2.5 5 8.7 15 25 34.5 46 69 10 15 19 26 34 50 70 95 140 2 3 Col 4 Induced Test (phase to ground) 2 times Nominal Voltage Col 5 Distribution Transformers 10 15 19 26 34 40 50 70 95 Class I Power Transformers 10 10 15 15 19 19 26 26 26 34 26 40 26 50 34 70 34 95 Winding Line-end BIL Min. Alternates Col 6 Col 7 1.4 2.9 5.8 10 17 29 40 53 80 30 45 60 75 95 125 125 200 250 1.4 2.9 5.8 10 17 29 40 53 80 30 45 60 75 95 150 200 200 250 Col 8 110 150 150 250 350 45 60 75 95 110 250 350 Col 9 200 Neutral BIL GrY Impedance Gr Y Col 10 Col 11 Col 12 30 45 60 75 75 75 75 95 95 30 45 60 75 75 95 125 150 200 30 45 60 75 75 75 75 95 95 30 45 60 75 75 95 125 150 200 For Nominal System Voltage greater than Maximum System Voltage use the next higher voltage class for applied test levels. Induced tests shall be conducted at 2.0* Nominal voltage. Bold typeface BIL's are the most commonly used standard levels Y-Y connected transformers using a common solidly grounded neutral may use neutral BIL selected in accordance with the low voltage winding rating. PJH Charlotte, NC March 18, 2008 7 Table 5: Class II Power Transformers, voltages in kV Induced Test (phase to ground) Max Nominal Applied Test Winding Line-end BIL Neutral BIL System System Delta & Fully Gr Y Impedance Enhanced One Hour Min. Alternates Gr Y Impedance Voltage Voltage Insulated Gr Y 7200 cy. Gr Y Col 1 Col 2 Col 3 Col 4 Col 5 Col 6 Col 7 Col 8 Col 9 Col 10 Col 11 Col 12 Col 13 Low Voltage Windings (69 kV and lower) <=17 <=15 34 26 26 20 15 110 110 110 26 25 50 26 34 29 24 150 110 110 36 34.5 70 26 50 41 32 200 110 125 48 46 95 34 70 55 42 200 250 110 150 73 69 140 34 95 81 63 250 350 110 200 High Voltage Windings (115 kV and higher) 121 115 173 34 95 120 105 350 450 550 110 250 145 138 207 34 95 145 125 450 550 650 110 250 169 161 242 34 140 170 145 550 650 750 825 110 350 242 230 345 34 140 240 210 650 750 825 900 110 350 362 345 518 34 140 360 315 900 1050 1175 110 350 550 500 N/A 34 140 550 475 1425 1550 1675 110 350 765 735 N/A 34 140 850 750 1950 2050 110 350 800 765 N/A 34 140 885 795 1950 2050 110 350 Notes: 1 For Nominal System Voltage greater than Maximum System Voltage use the next higher voltage class for applied test levels. Induced tests shall be conducted at 1.58 * Nominal voltage for one hour and 1.80 * Nominal voltage for enhanced 7200 cycle tests. Bold typeface BIL's are the most commonly used standard levels 2 3 Y-Y connected transformers using a common solidly grounded neutral may use neutral BIL selected in accordance with the low voltage winding rating. 4 For 735kV to 800 kV nominal system voltages, induce test levels do not follow rules in Note 2, and 1950 kV BIL is not a standard IEEE level. PJH Charlotte, NC March 18, 2008 8 Table 6: High Frequency Test Tables Lightning Chopped Wave Impulse (BIL) kV Crest Min. Time to Flashover, μs kV Crest, 1.2x50 μs 1.1 X BIL Class I & Dist Class II Switching Impulse kV Crest Col 1 Col 2 Col 3 Col 4 Col 5 30 45 60 75 95 110 125 150 200 250 350 450 550 650 750 825 900 1050 1175 1300 1425 1550 1675 1800 1950* 2050 33 50 66 83 105 120 138 165 220 275 385 495 605 715 825 900 990 1155 1290 1430 1570 1705 1845 1980 2145 2255 1.0 1.5 1.5 1.5 1.8 2.0 2.3 3.0 3.0 3.0 3.0 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 2.0 2.0 2.0 2.0 2.0 2.0 2.3 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 50 62 79 92 104 125 166 208 291 375 460 540 620 685 745 870 975 1080 1180 1290 1390 1500 1550/1620* 1700 Notes: *For 1950 kV BIL, a Switching Impulse (BSL) of 1550 kV is a special application for transposed lines to reduce switching impulse levels. For non-transposed lines, a Switching Impulse (BSL) of 1620 kV shoule be used for the 1950 kV BIL PJH Charlotte, NC March 18, 2008 9 Annex A (Informative) The following table of Front-of-Wave insulation and test levels has been included for information and historical benefit. The test levels in this table have come from past issues of C57.12.00, dating back to earlier than 1965 through 1980 issues. The Front Of Wave Test, Voltages in kV : Note that this test is no longer specified but is documented for historical purposes Lightning Front Of Wave Impulse (BIL) kV Crest Min. Time to Min. effective kV Crest, 1.2x50 μs Flashover, μs Rate Of Rise, (kV/ μs) Col 1 Col 2 Col 3 Col 4 30 45 60 75 95 110 125 150 200 250 350 450 550 650 750 825 900 1050 1175 1300 1550 75 75 125 165 165 195 220 260 345 435 580 710 825 960 1070 1150 1240 1400 1530 - 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.58 0.71 0.825 0.96 1.07 1.15 1.24 1.4 1.53 - 125 125 210 210 275 430 430 430 575 725 850 850 850 850 850 850 850 850 850 - PJH Charlotte, NC March 18, 2008 10 Table III Test Values For Repaired Transformers 1. Transformers in the field do not get impulse tests. 2. Transformers that are returned to the factory with field service are to be tested at 85% of the new values. 3. Transformers that have minor repairs or where only one coil is replaced generally are also tested to 85% of the new values. 4. Transformers where 2 or more coils are replaced are generally tested to full rated values. There is naturally a requirement for agreement between purchaser and supplier. PJH Charlotte, NC March 18, 2008 11 Future Direction for Taskforce: 1. Place Task Force on idle while C57.12.00R is balloted. 2. Address issues in C57.12.00 that are referred back to Taskforce. 3. Disband Taskforce at Spring 2009 meeting in Miami. PJH Charlotte, NC March 18, 2008 12 Summary of Blume’s Dielectric Relationships of Test Valves to System Voltage in 1937 1. Low Frequency 1 Minute withstand voltage Infinite time withstand voltage 1.5 (Page 388*) 1.25 (Page 473*) 2.2 - 3.0 (Page 476*) 2. High Frequency 1 time Full wave withstand Multiple strokes Full wave withstand 1.5 x 40µsec 60 Hz withstand *Transformer Engineering: A Treatise on the Theory, Operation and Application of Transformers By L.F. Blume,, G. Camilli, A. Boyajian and V.M. Montsinger. © 1938 John Wiley and Sons, Inc. PJH Charlotte, NC March 18, 2008 13 Minimum BIL Selection from Surge Arrester Characteristics Arrester protection level V1 V2 VMX L-G V arrester protection level to VMX L-G From Blume: Minimum BIL = 1.25 X V2 PJH Charlotte, NC March 18, 2008 14 Grounded Wye-Connected Arresterd Application Chart In Accordance with C62.2 Methods Courtesy of Mike Comber, Ohio Brass Co. Rev.: 0 Date: 11/2/99 Shielding Practice Unshielded Systems Shielded Systems Nominal Nominal Duty System System Cycle Vols kV(L-L) Vols kV(L-G) Volts kV 1.2 2.5 5 8.7 15 25 34.5 46 69 115 138 161 230 345 500 765 0.69 1.44 2.89 5.02 8.66 14.43 19.92 26.56 39.84 66.40 79.68 92.96 132.79 199.19 288.68 441.69 3 3 6 9 12 18 27 36 54 90 108 120 172 258 MCOV rms 2.55 2.55 5.10 7.65 10.20 15.30 22.00 29.00 42.00 70.00 84.00 98.00 140.00 209.00 304.00 462.00 SHIELDED SYSTEM Discharge Vrev.@ Vrev./.75*1.25 10kA 10kA 8.00 8.00 15.80 23.50 31.40 47.10 67.70 98.20 122.00 202.00 243.00 283.00 404.00 604.00 850.00 1290.00 8.98 10.04 19.88 30.60 43.65 67.51 95.87 135.75 178.33 295.89 355.66 414.44 591.77 885.66 1258.20 1914.54 14.97 16.73 33.14 51.00 72.74 112.52 159.78 226.26 297.22 493.14 592.77 690.73 986.29 1476.10 2097.00 3190.91 Vrev*1.25 84.39 119.83 169.69 222.91 369.86 444.58 518.05 739.71 1107.07 1572.75 2393.18 UNSHIELDED SYSTEM Discharge Vrev.@ Vrev./.75*1.25 40kA 40kA 10.30 10.30 20.30 30.20 40.40 60.60 87.00 115.00 151.00 251.00 301.00 351.00 502.00 752.00 1000.00 1520.00 11.28 12.34 24.38 37.30 52.65 81.01 115.17 152.55 207.33 344.89 413.66 482.44 689.77 1033.66 1408.20 2144.54 18.80 20.57 40.64 62.17 87.74 135.02 191.94 254.26 345.55 574.81 689.44 804.07 1149.62 1722.76 2347.00 3574.24 Vrev*1.25 101.26 143.96 190.69 259.16 431.11 517.08 603.05 862.21 1292.07 1760.25 2680.68 1) Shielded Systems use 10 kA discharge voltage protection levels 2) Unshielded Systems use 40 kA discharge voltage protection levels 3) Transmission and subtransmission systems are shielded, having the neutral (ground) lead physically located above the line leads. 4) Distribution systems through 69 kV are normally unshielded with the neutral located below the line leads. PJH Charlotte, NC March 18, 2008 15 Delta-Connected Arresterd Application Chart In Accordance with C62.2 Methods Courtesy of Mike Comber, Ohio Brass Co. Rev.: 0 Date: 11/2/99 Shielding Practice Unshielded Systems Shielded Systems Nominal Nominal Duty System System Cycle Vols kV(L-L) Vols kV(L-G) Volts kV 1.2 2.5 5 8.7 15 25 34.5 46 69 115 138 161 230 345 500 765 0.69 1.44 2.89 5.02 8.66 14.43 19.92 26.56 39.84 66.40 79.68 92.96 132.79 199.19 288.68 441.69 3 3 6 12 18 36 45 60 90 144 172 228 312 MCOV rms 2.55 2.55 5.10 10.20 15.30 29.00 36.50 48.00 70.00 115.00 140.00 180.00 245.00 340.00 SHIELDED SYSTEM Discharge Vrev.@ Vrev./.75*1.25 10kA 10kA 8.00 8.00 15.80 31.40 47.10 89.20 113.00 139.00 202.00 332.00 404.00 520.00 708.00 950.00 8.98 10.04 19.88 38.50 59.35 109.61 141.17 176.55 258.33 425.89 516.66 651.44 895.77 1231.66 14.97 16.73 33.14 64.17 98.91 182.68 235.28 294.26 430.55 709.81 861.10 1085.73 1492.95 2052.76 Vrev*1.25 137.01 176.46 220.69 322.91 532.36 645.83 814.30 1119.71 1539.57 UNSHIELDED SYSTEM Discharge Vrev.@ Vrev./.75*1.25 40kA 40kA 10.30 10.30 20.30 40.40 60.60 115.00 146.00 173.00 251.00 413.00 502.00 645.00 878.00 1118.00 11.28 12.34 24.38 47.50 72.85 135.41 174.17 210.55 307.33 506.89 614.66 776.44 1065.77 1399.66 18.80 20.57 40.64 79.17 121.41 225.68 290.28 350.92 512.22 844.81 1024.44 1294.07 1776.29 2332.76 Vrev*1.25 169.26 217.71 263.19 384.16 633.61 768.33 970.55 1332.21 1749.57 1) Shielded Systems use 10 kA discharge voltage protection levels 2) Unshielded Systems use 40 kA discharge voltage protection levels 3) Transmission and subtransmission systems are shielded, having the neutral (ground) lead physically located above the line leads. 4) Distribution systems through 69 kV are normally unshielded with the neutral located below the line leads. PJH Charlotte, NC March 18, 2008 16 Porcelain Housed Station Class Arresters PJH Charlotte, NC March 18, 2008 17 DynaVar Type VH5 Heavy Duty Station Class Gapped Metal-Oxide Surge Arresters (Double Column of Value Elements) Maximum Continuous Operating 10-Second Voltage Voltage (MCOV) Rating kV rms kV 304 318 340 462 378 396 420 576 Maximum 0.5 us Discharge Voltage kV (1) Maximum Switching Surge Discharge Voltage (kV (2) 5 kA 10 kA 20 kA 40 kA 1023 1070 1142 1596 738 774 825 1120 806 843 500 1223 850 890 950 1290 905 947 1012 1380 1000 1046 1118 1520 Maximum Discharge Voltage using an 8 x 20 us Current Wave - kV 1) Maximum discharge voltage for an impulse current wave which produces a voltage wave creating a 5 0.5 s. Discharge currents are 15 kVA for 304=340 MCOV and 30 kA for 462 MCOV. This can be used for coordination where front-of-wave sparkover formerly was used. 2) Discharge voltage of 3 kA for a surge of 45 s time to crest. PJH Charlotte, NC March 18, 2008 18 BACKGROUND INFORMATION George Iliff Reference (Bonneville Power) Low Frequency Tests - Induce and Applied V Test = 2 x V system H2 100% H1 H2 58% G H3 A - NORMAL 100% 58% H1 H2 G R N 58% H3 B - FAULT ON UNGROUNDED SYSTEM H1 G R=O H3 C - FAULT ON EFFECTIVELY GROUNDED SYSTEM NOTE: “G’ REFERS TO THE GROUND VOLTAGE AT THE TRANSFORMER, RELATIVE TO THE LINE TERMINAL VOLTAGES. THIS DETERMINES THE COLTAGE IMPOSED ON THE TRANSFORMER INSULATION. PJH Charlotte, NC March 18, 2008 Figure 1 - Voltage Relationhips on faulted windings 19 Liquid Dielectric Test Tables Task Force (C57.12.00) Low Frequency Test Comparison PJH Charlotte, NC March 18, 2008 20 Liquid Dielectric Test Tables Task Force (C57.12.00) High Frequency Test Comparison PJH Charlotte, NC March 18, 2008 21