ML20133D477
| ML20133D477 | |
| Person / Time | |
|---|---|
| Site: | Hope Creek  |
| Issue date: | 08/05/1985 |
| From: | Mittl R Public Service Enterprise Group |
| To: | Butler W Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8508070348 | |
| Download: ML20133D477 (7) | |
Text
{{#Wiki_filter:F O I)#S G Compeny Publ.c Sereco Elecinc and Gas 80 Park Plaza, Newark, NJ 07101/ 201430 8217 MAILING ADDRESS / P.O. Box 570, Newark, NJ 07101 Robert L Mitti General Manager Nuclear Assurance and Regulation August 5, 1985 Director of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission 7920 Norfolk Avenue Bethesda, MD 20814 Attention: Mr. Walter Butler, Chief Licensing Branch 2 Division of Licensing Gentlemen: SAFETY EVALUATION REPORT OPEN ISSUE 7 HOPE CREEK GENERATING STATION DOCKET NO. 50-354 Pursuant to the May 28, 1985, telecon on SER Open Issue 7, the following information is attached for your review: o Data for test current versus the maximum short circuit condition in each test case. o a statement regarding the test performance of the metal clad cable compared to the rigid steel conduit. Should you have any questions in this regard, please contact us. Very truly yours, [/ 850807034s 850805 PDR ADOCK 05000354 E PDR Attachment C D. H. Wagner USNRC Licensing Project Manager A. R. Blough USNRC Senior Resident Inspector OI The Energy People in. 95>4912 (4W 7-83
ATTACHMENT 1 Safety Evaluation Report-Open Item 7 and Confirmatory Item 29 On May 28, 1985 a telephone conference call was held to discuss the information submitted by PSE&G letter to NRC dated April 4, 19 8 5, R. L. Mittl to A. S chwencer. The letter submitted for staf f review a copy of Wyle Test Report 17 730-01, " Cable and Raceway Physical Separation Verification Testing" dated March 1985. Mr. Wagner and Mr. Rhow of the NRC s taf f requested addi-tional information from PSE&G in order to complete the review of the subject i tems. The following provides the requested additional information: A. Test Currents vs. Maximum HCGS Fault Currents The test was designed to address a concern expressed by the NRC staf f reviewer with regard to cable and raceway separation. In the discussions with the staf f, PSE&G and BPC of fered to test using maximum short circuit cu r rents; howeve r, the staf f reviewer was concerned that the I 2t value for the maximum short circuit current would not be as destructive as that of an overload current that could persist for a longer time. This, in fact, is the case. Thus, a comparison of the heating effects on the faulted test cables represented by a summation of I 2t values imposed by the f ault currents with those of the maximum calcu-lated f ault currents on the corresponding Hope Creek cables is provided in the attached tabulation. Table I of the Wyle test report tabulates the various sizes of cables that were tested together with the test currents used to cause the faulted cable condition (open circuit with or without ignition of the cable ). Attached Table A has been prepared to correlate selected information from the Wyle Table I with the corresponding Hope Creek design configuration in order to com-pare the test currents with maximum f ault currents expected in the actual design. The tabulation is arranged to show the maxi-mum I2t values imposed on each of the test cable sizes until the test cable reached a faulted condition, i.e., the same test cable size is used in more than one test configuration and only the maximum I2 t values calculated for each test configuration is shown. Corresponding to the test values are the design values which have been conservatively derived to provide compar-ison. The derivation of the design values is based on conserva-tive assumptions that the fault current available is not reduced by impedances in the circuits (cables and trans fo rme rs ) and that the maximum operating times of the primary overcurren t protective devices are used. / F4/18,
As shown by the tabulation the test values significantly exceed the HCGS design values with respect to heating ef fects caused by faulted cables. It is concluded that the Hope Creek design will prevent f aulted cables in the same or similar configuration as tested from af fecting the redundant cables because an over-current device, primary or upstream backup if the primary device fails, in each circuit will clear fault currents such that temperature obtained in the testing are not reached in the de s ig n. Also, the Hope Creek design does not pe rmi t circu its to be loaded to rated ampacity of a cable since derating factors are used to account for ambient tempe ratures and ins talla tion in raceways. B. Metal-Clad Cable and Rigid Steel Conduit The metal cladding of the metal-clad cable pe rforms the same f unction as the rigid steel conduit in providing protection to the enclosed cable from external hazardh of a limited nature. A discussion of testing on the metal-clad cable is provided in FSAR Section 1.8.1.75. F4/18 'IABLE A Page 1 of 4 QJmparison of Wy3e Test Configurations with HmS Design Wyle Test Configuration ICGS Design Test Confi-l Faulted j Test Values _ Design Values l Z It l Basis for Maximtun Fault guration (Cable Current, Time, Idt Maximum Fault , Time, Number l Size Amperes Seconds! l Current, Amperes l Seconds lCurrent and Duration 1 and 2 2/C No. 210 90 0 39.7 x 100 The test configurations 2 AWG 550 1500 453.8 x 106 represent Cable Spreadirg 700 3150 1543.5 x 106 Roan tray irstallations. 900 1830 1482.3 x 106 The largest cable in this) 1200 300 432 x 106 area is 2/C No. 21HG Wiich is used to supply Total = 12W dc power to relay 3951.3 x 106 8430 .011 .781x106 panels (C654 series). Note 1 The cable has a 50A cir-cuit brecter in distribu-tion panel G18 for wer-current trotection. To provide conservative de-sign values, the fault current available at the l distribution panel is l assmed to be the sane as-at its upstrean switch-gear and the duration is based on the 50A circuit l l ' breaker's cperating time. 3 ard 4 1/C 500 477 900 204.8 x 106 The test configurations MCM 1000 2760 2760 x 106 represent a 480V ac power 1400 840 1646.4 x 106 cable enclmed and sepa-1750 4080 12495 x 106 rated by 1" fran an cpen 1900 2580 9313.8 x 106 cable trry. This power 2077 1860 8023.9 x 106 cable is typically a motor 2200 540 2613.6 x 106 control center feeder cable with 500 MCM as the i Total = 30000 .2 180x106 largest cable. To pro-37057.5 x106 vide conservative design Note 2 values, the fault current available at an mit sub-station tus is sinwn and the duration is based on the cperatirg time cf an unit stbstation circuit l l l l l breaker.
'IABLE A Page 2 of 4 Cbmparison of Wyl'a 'Ibst (bnfigurrtion", with HG;S Design Wyle Test Configuration 10GS Design Test Confi-l Faulted l Test Values _ Design Values l guration (Cable (Current, Time, 14t Maximum Fault l Time, lIt Basis for Maximtun Fault Number I Size l Anperes Seconds Current, Anperesl Seconds l l Current and Duration l 5,6,7 3/C No. 600 900 324 x 106 The test configurations and 8 2/O 900 900 729 x 106 represent 480V ac power 1050 960 1058.4 x 106 cables drcppirg mt of 1350 1860 3389.9 x 106 cable trays or enclmed 1700 2220 6415.8 x 106 in rigid steel corduits 2000 1020 4080 x 106 with a sparation dis-2500 480 3000 x 106 tance cf 1/2" or 1", as 6000 60 2160 x 106 defined in the tests, fran a corduit or free air cables. 'Iypically Total = the power cables are 21157.1 x 106 25000 .02 12.5 x 106 for motor control center Note 3 loads of motors, battery diargers ard heaters. Overcurrent protection is govided by a circuit breaker in the MCC. To provide comervative ( design values the fault I current available at the MCC bus is slown ard the duration is based on the (perating time cf a MCC circuit breaker. F6/18
TABLE A Page 3 of 4 Comparison of Wylo 'Ibst Configurations with HWS Design Wyle Test Configtration HCGS Design ( Test Confi-{ Faulted j Test Values _ Design Values ! Basis for Maximum Fault ) Z 2 guration l Cable l Current, Time, It Maximum Fault
- Time, lIt Number l Size IAmperes Seconds' Current, Amperes Secondsl Current and Duration 11 and 12 4/C No.
492 900 217.9 x 106 The test configurations 2/WG-MCl 692 180 86.2 x 106 represent metal-clad 1000 3540 3540 x 106 cable separation fran 1500 2640 5940 x 106 cable tray. Typically the cable is a 480/27N ac power cable fran a Total = notor control center 9784.1 x 106 25000 .02 12.5 x 106 to a lightirg distribu-Note 4 tion panel. Overcurrent' protection is [rovided by a circuit breaker in l the MCC. The design 2 values stown are the same as stown for Test Configuration Nos. 5, 6, 7 and 8 to prcwide con-j l l l servatism. 1 13 and 14 4/C No. 160 900 23 x 106 The test configurations 10/WG-220 1620 78.4 x 106 represent armor-clad AC 280 2400 188.2 x 106 cable separation fran 340 1300 152.7 x 106 cable tray. Typically 450 960 194.4 x 106 the cable is a lighting 600 210 75.6 x 106 branch feeder circuit I to lightirg fixtures. Total = Overaurrent Irotection 712.2 x 106 25000 .02 12.5 x 106 is gravided in the light Note 5 irg distribution panel. Even tlough the fault current ard daration available at the light-irg distribution panel will be significantly less than that available l l l
- at its upstrean MCC bus, F4/18 i
TABLE A Page 4 of 4 Comparison of Wyle 'Ibst Configurations with H(ES Design Wyle Test Configuration 10GS Design Test Confi-j Faulted l Test Values _ 1 Design Values l 2 guration l Cable l Current, Time, 14t , Maximum Fault l Time, l1 t Basis for Maximurn Fault Number lSize IAmperes Seconds l Current, Amperesl Seconds l Current and Duration 13 ard 14 4/C No. the same design values (Cont'd) 101HG-ACl for Test Configuration Nos. 5, 6, 7 and 8 are shown here for comer-l . vatism. l l 13 ard 14 Heliax-l 100 780 7.8 x 106 The test configurations coaxial 200 720 28.8 x 106 represent tHF radio an-300 1620 145.8 x 106 tenna cable separation 400 1020 163.2 x 106 fran cable tray. The 500 1020 255 x 106 cable carries low power 1 600 20 7.2 x 106 signals. Primary over-current Irotection is provided in the radio Total = cabinet with backup 607.8 x 106 250 .011 .0006875 protection trovided by a Note 6 x 106 20A fum in the 12W ac distribution panle IIU484. The fault cur-rent available is fran i the upstrean inverter Wich has a limited i output. l l l 1 NOTES 1. Test Values stown are based on Test Configuration No. I results. 2. Test Values sinwn are based on Test Configuration No. 3 results. 3. Test Values stown are based on Test Configuration No. 6 results. 4. Test Values stown are based on Test Configuration No.12 results. 5. Test Values sinwn are based on Test Configuration No.13, Test I results. 6. Test Values stown are based on Test Configuration No.14, Test 2 results. l l l l l l l l l F4/18}}