TCE CONSULTING ENGINEERS LIMITEDSHEET i OF i 30421007-3CL00010-P0D 13.8 kV MV CABLE SIZING REPORT SAUDI ELECTRICITY COMPANY EASTERN OPERATING AREA Dammam, Saudi Arabia GENERATION EXPANSION OF ARAR POWER PLANT (CONTRACT NO : 30421007/00) DESIGN BASIS FOR 13.8kV MV CABLE SIZING DOCUMENT NO : 30421007-3CL-00010-P0D MARCH 2005 ENGINEERING CONSULTANT TCE CONSULTING ENGINEERS LIMITED 73/1, ST.MARK'S ROAD BANGALORE 560001 INDIA CONTRACTOR: AL-TOUKHI COMPANY FOR INDUSTRY & TRADING P.O.BOX 497, RIYADH 11411, KINGDOM OF SAUDI ARABIA TEL.00966-1-4633660 : FAX.00966-1-4631150 P0D 03.03.2005 P0C 15.12.2004 P0B 30.10.2004 P0A 28.08.2004 REV NO. DATE 276463800.xls SECTION :cover sheeet MP SR MP SR MP SR MP SR PREPARED BY CHECKED BY CLEARED BY APPROVED BY SHEET 1 OF 10 xls SECTION :cover sheeet PREPARED BY CHECKED BY CLEARED BY APPROVED BY SHEET 2 OF 10 . DATE 276463800.REV NO. 0 CABLE SIZING REPORT SUMMARY 276463800.xls SECTION :Index SHEET 3 OF 10 .8kV CABLE SIZING REPORT DOCUMENT NO.0 GENERAL PARAMETERS 4.0 STANDARDS & REFERENCES 3.0 CONCLUSION 6.0 SIZING CRITERIA 5. 30421007-3CL-00010-P0D CONTENTS SECTION DESCRIPTION 1.GENERATION EXPANSION OF ARAR POWER PLANT (CONTRACT NO : 30421007/00) ARAR 13.0 SCOPE 2. GENERATION EXPANSION OF ARAR POWER PLANT (CONTRACT NO : 30421007/00) 276463800.xls SECTION :Index SHEET 4 OF 10 . 1022 as per Cl.1 page 70 of 336.7/15kV Grade) from Unit#7 Generator Circuit Breaker or Unit#8 Generator Circuit Breaker to Unit Auxiliary Transformer of UAT 307 or UAT 308.Cable Selection -Engineering standards.6 Electrical System Study Report Doc No: 30421007-3CL-00004-P0B 3. 2. According to SAUDI CABLE COMPANY Catalogues for Medium Voltage Cables page 61 of section-6 the nominal current carrying capacities for 1Cx630Sqmm Unarmoured cables are.4. XLPE Unarmoured cable size has been selected.0 DOCUMENT NO.No.4.in flat formation 30 Deg C and Thermal resistivity of soil = 1.4.4 kA for 3 second as per Cl.Medium Voltage Cables Catalogues 2.Depth of Burried Cables .8 kV = 52.01.4 Key One Line Diagram for Arar Plant Drawing No: KA667481 REV P0E 2. IEC 60364-5-523 Selection and erection of electrical equipment-Current Carrying capacities in wiring system.3 Amps However.8kV cable to UAT 307 1250 kVA = 3 x 13.3 SES-P-104. the minimum size of 1C x 630 Sqmm/Phase Cu.1 CURRENT CARRYING CAPACITY The total load current to be carried by 13.Current Carrying Capacity.8kV CABLE SIZING REPORT 1.5 SAUDI CABLE COMPANY .03 .8kV cable of PTS-1022.2 page 71 of 336 of PTS .2K-m/W. 2.2 STANDARDS & REFERENCES IEC 60986-short circuit sizing.xls SECTION :Notes and Sizing Cal Current Carrying capacity in Amps for 1C x 630 Sqmm 665 SHEET 5 OF 10 .Ground Temperature at a depth of 1 meter .No. 30421007-3CL-00010-P0D SCOPE Scope of this report is to calculate the 13.0 2.8kV Cable size (8. Laying Conditions(in duct) Laid directly in ground or duct ways.1 2.0 = = = = = 1 meter 35 Deg C 2 Deg C -m/w 50 Deg C 68.11 of Electrical System Study report Doc No:30421007-3CL-00004-P0B SIZING CRITERIA The Power Cable size shall be selected on the basis of : .Ambient air Temperature . Ground temp. . depth of laying = 0.No. Cl. 4. as per the Data Schedule of 13.Permissible Voltage Drop.Short Circuit current 4. 2.Short circuit Rating.8m 276463800.01.GENERATION EXPANSION OF ARAR POWER PLANT (CONTRACT NO : 30421007/00) ARAR 13.Average Thermal Soil resistivity . .0 GENERAL PARAMETERS . 8m Laying Conditions (in Air) DOCUMENT NO.GENERATION EXPANSION OF ARAR POWER PLANT (CONTRACT NO : 30421007/00) ARAR 13. depth of laying = 0. Ground temp.xls SECTION :Notes and Sizing Cal SHEET 6 OF 10 . 30421007-3CL-00010-P0D 720 Current Carrying capacity in Amps for 1C x 630 Sqmm Laid in Air (tray).2K-m/W.in trefoil formation 30 Deg C and Thermal resistivity of soil = 1. in trefoil formation Ambient Temperature 40 Deg C 965 276463800.in flat formation Ambient Temperature 40 Deg C 980 Laid in Air (Tray).8kV CABLE SIZING REPORT Laid directly in ground or duct ways. = Power Factor = 0.ambient Air Temperature 50 DegC K5 = 0.3Amps under all site conditions.Laying on Cable Tray(in touching form) K6 according to: . 4. current Laying cable in trefoil formation.Thermal Resistivity of soil 2.Depth of Laying 1m K3 = 0.No of ducts in ground = 3 Derating Factor Kd Kd = = K1 x K2 x K3 x K4 0. current = Laying cable in trefoil formation.3/2 = 26.052 = Cable Voltage in V = 13800 276463800.2 VOLTAGE DROP SIZING : From drg no KA-667496 REV P0A.02 Amps 450.installation system = spacing between two adjacent(center line to center line) ducts equal 0.6 .xls SECTION :Notes and Sizing Cal Note: The full load current for 2Runs of 1Cx630Sqmm/phase is 52. current = = 980 x Ka = 965 x Ka = 750. The Voltage drop check is calculated as follows : = V% 3 x(RCOS + XSIN) x I x L x 100 /Un for three phase system Where. Add 10m at each end.89 .43 Amps Maximum current carrying capacity of Cable Laid in Air(Cable Tray) (after considering derating factor) Laying cable in flat formation.3m .0Deg C-m/W K2 = 0. 1C x 630 Sqmm/Phase cable can carry the required load current of 52.15 Amps SHEET 7 OF 10 .No of trays = 3 = 0.84 Page 70 cables of Saudi .8 COS SIN = = 0. Hence for 1Run of 1Cx630Sqmm/phase is considered as 52. so total length = 52m.95 Page 69 medium voltage .86 Derating Factor Ka Ka = = Page 61of Section 6 medium voltage cables of Saudi Cable Company catalogue as per IEC 60364-5-523 table 52-E5.Group Rating Factor K4 = 0.6256 Derating factor Ka for Cable installed in free air:(for both Flat/trefoil formation) .3A.98 Page 69 cable company . cable length = 30m.GENERATION EXPANSION OF ARAR POWER PLANT (CONTRACT NO : 30421007/00) ARAR 13. also add another 12m. the maximum current carrying capacity of the selected 1C x 630Sqmm/phase cable as follows Maximum current carrying capacity of Cable Laid in Duct ways(after considering derating factor) Laying cable in flat formation.7654 According to the above.8kV CABLE SIZING REPORT DOCUMENT NO. current = 665 x Kd = 720 x Kd = 416.09 Amps 738. 30421007-3CL-00010-P0D The following Derating factors have been considered as per SAUDI CABLE COMPANY Catalogues for the site conditions specified: Derating factor Kd for Cable Laid in Duct ways :(for both Flat/trefoil formation) of Section. Page 77 K5 x K6 0. -according to: .15 L Un = Length in Km = 0.61 Amps As per above calculation.80 Page 71 catalogues.Ground Temperature 35 DegC K1 = 0.6 I = Full load Current in A = 26.installation system in three phase circuits . GENERATION EXPANSION OF ARAR POWER PLANT (CONTRACT NO : 30421007/00) ARAR 13. 30421007-3CL-00010-P0D Page 56 & 67of Section 6 medium voltage cables of Saudi Cable Company catalogue SHEET 8 OF 10 . Voltage drop is within the limits only.0434 X = Reactance /Km = 0.11 The Voltage Drop V% = 0.xls SECTION :Notes and Sizing Cal DOCUMENT NO.002 % Volts which is < 5% Hence.8kV CABLE SIZING REPORT R = Resistance /Km = 0. 276463800. 65 kA The selected 1R x 1C x 630Sqmm/Phase cable size can withstand upto 51. 5.6 the maximumshort circuit current carrying capacities for the conductor calculated with the formula: 142 x S I = t Where.GENERATION EXPANSION OF ARAR POWER PLANT (CONTRACT NO : 30421007/00) ARAR 13.3kA for 3 seconds.3 DOCUMENT NO.30 kA The selected 2Rx1Cx630Sqmm/Phase cable size can withstand upto 103. Unarmoured cable has been selected based on the above calculations. 276463800. XLPE insulated.8kV CABLE SIZING REPORT 4. the maximum short circuit current is 68. the maximum short circuit current is 68.4kA for 3 seconds only.9. I = Maximum Allowable conductor Short Circuit Current in Amps t = Duration of Short circuits in seconds S = Cross Sectional Area of Current Carrying conductor in Sqmm K = Temperature co-efficient of conductor resistance.7/15kV Grade.0 CONCLUSION From Unit#7 Generator Circuit Breaker or Unit#8 Generator Circuit Breaker to Unit Auxiliary Transformer UAT 307 or UAT 308 8.65kA for 3 seconds only. 30421007-3CL-00010-P0D SHORT CIRCUIT RATING. Whereas. According to SES-P-104. Therefore. 2R x 1C x 630Sqmm/Phase cable size has been selected for short circuit current carrying capacity 142 x 2 x 630 I = 3 I = 103. Whereas.4kA for 3 seconds. Copper Conductor of size 2R x 1C x 630 Sqmm/Phase.xls SECTION :Notes and Sizing Cal SHEET 9 OF 10 .03 Engineering standards Cl No:4. 142 x 630 I = 3 I = 51. = 142 for copper XLPE therefore. GENERATION EXPANSION OF ARAR POWER PLANT (CONTRACT NO : 30421007/00) 6.002 SHEET 10 OF 10 .02 450.6256 0.xls SECTION :Cable Sizing Report Summary 52.7654 416.30 IN AIR 2 RUN OF 2 RUN OF 1C X 630 1C X /Phase 630 /Phase DERATING FACTOR CURRENT CARRYING CAPACITY OF CABLE AFTER DERATING FACTOR (SINGLE RUN) CABLE LAID IN AIR(CABLE CABLE LAID IN DUCT CABLE LAID IN AIRCABLE LAID IN DUCT CABLE LAID IN AIR(CABLE BANKS CABLE TRAYS TRAY) BANKS TRAY) (IN BOTH (IN FLAT/TREFOIL BOTH FLAT/TREFOIL IN FLAT IN TREFOIL IN FLAT IN TREFOIL IN FLAT IN TREFOIL IN FLAT IN TREFOIL FORMATION) FORMATION) FORMATION FORMATION FORMATION FORMATION FORMATION FORMATION FORMATION FORMATION CABLE LAID IN DUCT BANKS 665. 30421007-3CL-00010-P0D LOAD VOLTAGE kVA VOLTS FULL LOAD CURRENT CARRYING CAPACITY OF CABLE (SINGLE CABLE SIZE SELECTED CURRENT RUN) IFL AMPS SQ.43 750.00 0.0 CABLE SIZING REPORT SUMMARY ARAR 13. FEEDER DESCRIPTION DOCUMENT NO.052 0.09 738.00 720.00 980.61 LENGTH OF CABLE % VOLTAGE DROP KM % 0.00 965.8kV CABLE SIZING REPORT SL NO.MM IN DUCT BANKS 1 Unit#7 Generator Circuit Breaker or Unit#8 Generatort Circuit Breaker TO UNIT AUX TRANSFORMER UAT 307 or UAT 308 1250 13800 276463800.