Rev 1 to Open Circuit of Current Transformer SecondaryML20137M185 |
Person / Time |
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Site: |
Clinton ![Constellation icon.png](/w/images/b/be/Constellation_icon.png) |
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Issue date: |
10/17/1983 |
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From: |
SARGENT & LUNDY, INC. |
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To: |
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Shared Package |
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ML20137M160 |
List: |
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References |
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19-BD-5, 19-BD-5-R01, 19-BD-5-R1, NUDOCS 8601280211 |
Download: ML20137M185 (8) |
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Category:TECHNICAL SPECIFICATIONS & TEST REPORTS
MONTHYEARML20209E0551999-07-0606 July 1999 1999 Business Plan ML20206F2231999-04-27027 April 1999 NRC Manual Chapter 0350 Restart Action Plan for Clinton Power Station ML20199H2771999-01-20020 January 1999 Proposed Tech Specs Changing Table 3.3.8.1-1 to Revise Allowable Values for Degraded Voltage Relay Reset & Dropout Setpoints as Specified Per Items 1.c,1.d,2.c & 2.d ML20206E6281998-12-31031 December 1998 Rev 17 to ODCM for Clinton Power Station ML20196A0941998-11-20020 November 1998 Proposed Tech Specs Re Div 3 Diesel Generator Droop Issue ML20196A1501998-11-20020 November 1998 Revised Pages Constituting Rev 3 to CPS TS Bases,Consisting of Pages Annotated with Rev Numbers 3-1,3-2,3-3,3-4 & 3-5. Changes to Text Identified with Rev Bars.No Rev Bars Included for Changes to Format ML20155A5631998-10-23023 October 1998 Proposed Tech Specs LCO 3.6.1.9, FW LCS (FWLCS) for Implementation of FWLCS Mode of RHR Sys U-603088, Proposed Tech Specs Section 5.5.13,allowing Next Scheduled Performance of LLRT of Primary Containment Penetration for RPV Head Spray Piping (IMC-042) to Be Deferred Until Seventh Refueling Outage (RF-7)1998-10-0505 October 1998 Proposed Tech Specs Section 5.5.13,allowing Next Scheduled Performance of LLRT of Primary Containment Penetration for RPV Head Spray Piping (IMC-042) to Be Deferred Until Seventh Refueling Outage (RF-7) ML20153F4201998-09-23023 September 1998 Corrected Proposed Tech Specs Bases Page B 3.8-94 Re SVC Protection Sys ML20237E4191998-08-24024 August 1998 Proposed Tech Specs SR 3.8.1.17,revising Acceptance Criteria for Meeting ready-to-load Requirement for Division 3 DG ML20237C3501998-08-17017 August 1998 Proposed Tech Specs Partially Reducing Load at Which DGs Are Required to Be Tested Per Affected SRs in Order to Reduce Stress & Wear on Machines While Still Sufficiently Challenging Machines to Confirm Operability ML20236X0071998-07-31031 July 1998 Proposed Tech Specs,Revising Acceptance Criteria of SRs 3.8.1.7,3.8.1.12,3.8.1.15 & 3.8.1.20 ML20236Q4661998-07-17017 July 1998 Rev 0 to Procedure 2800.93, Emergency Reserve Auxiliary Transformer Integrated Test ML20236Q4651998-07-17017 July 1998 Rev 0 to Procedure 2800.92, Emergency Reserve Auxiliary Transformer Integrated Test ML20236Q4571998-07-17017 July 1998 Rev 0 to Procedure 2800.91, Emergency Reserve Auxiliary Transformer Test ML20216B1511998-05-0404 May 1998 Proposed Tech Specs Pages,Incorporating Requirements for Static Var Compensator (SVC) Protection Sys Under New TS ML20217M3351998-04-27027 April 1998 Proposed Tech Specs Re Mgt Changes Occurring in Operations Organization at Plant ML20203D5651998-02-19019 February 1998 Plan for Excellence ML20212C6951997-10-23023 October 1997 Proposed Tech Specs,Constituting Rev 2 to CPS TS Bases.Rev Consists of Pages Annotated W/Rev Numbers 2-1 Through 2-14 ML20149J1701997-07-22022 July 1997 Proposed Tech Specs Requesting Exemption to 10CFR50,App a, General Design Criteria to Allow Operation W/Identified Offsite Circuit Condition ML20149H8991997-06-30030 June 1997 CPS Long Term Improvement Plan U-602714, Proposed Tech Specs Table 3.3.8.1-1 Re Loss of Power Instrumentation1997-04-0101 April 1997 Proposed Tech Specs Table 3.3.8.1-1 Re Loss of Power Instrumentation ML20133F2051997-01-0707 January 1997 Proposed Tech Specs 2.0 Re Safety Limits ML20133A5951996-12-13013 December 1996 Proposed TSs Re Transfer of Minority Ownership ML20134M3181996-11-19019 November 1996 Proposed Tech Specs Revising Table 3.3.8.1-1, Loss of Power Instrumentation, by Dividing Function, Degraded Voltage - 4.16 Kv Basis & Degraded Voltage Dropout - 4.16 Kv Basis, re-numbering Items in Table & Revising Associated Notes ML20128K0711996-10-0404 October 1996 Proposed Tech Specs 3.3.8.1,adding Action Statement & Note Requiring Restoration of Inoperable Degraded Voltage Relays, Rev to Table 3.3.8.1-1 ML20134C1631996-09-20020 September 1996 Proposed Tech Specs,Revising TS 3.3.4.1, End of Cycle Recirculation Pump Trip Instrumentation, to Delete SR 3.3.4.1.6 Which Requires RPT Breaker Interruption Time to Be Determined at Least Once Per 60 Months ML20116N1101996-08-15015 August 1996 Proposed Tech Specs 2.0, Safety Limits, Changing TS to Incorporate Revised SLMCPR as Calculated by GE for CPS Cycle 7 U-602619, Proposed Tech Specs 5.0, Administrative Controls, Deleting Examples Currently Included in Parentheses1996-08-15015 August 1996 Proposed Tech Specs 5.0, Administrative Controls, Deleting Examples Currently Included in Parentheses U-602623, Proposed Tech Specs 3.10.10, Single Control Rod Withdrawal- Refueling1996-08-15015 August 1996 Proposed Tech Specs 3.10.10, Single Control Rod Withdrawal- Refueling ML20137A1101996-08-14014 August 1996 Rev 19 to App V Second 10-Yr Interval Pump & Valve Testing Program Plan ML20137A1021996-07-10010 July 1996 Rev 5 to App IV Second 10-Yr Interval Inservice Exam Plan ML20113E7261996-06-28028 June 1996 Proposed Tech Specs,Allowing Removal of Inclined Fuel Transfer Sys Primary Containment Blind Flange While Primary Containment Required to Be Operable U-602591, Proposed Tech Specs,Allowing Utilization of RWP or Equivalent to Control Entry Into High Radiation Area, Clarifying Example Given in TS of Individuals Qualified in Radiation Protection Procedures1996-06-21021 June 1996 Proposed Tech Specs,Allowing Utilization of RWP or Equivalent to Control Entry Into High Radiation Area, Clarifying Example Given in TS of Individuals Qualified in Radiation Protection Procedures ML20108C9431996-05-0101 May 1996 Proposed Tech Specs,Implementing 10CFR50,App J - Option B ML20107L0011996-04-19019 April 1996 Proposed Tech Specs,Revising Listed TS to Eliminate Core Alterations as Applicable Condition for Which Associated LCO Must Be Met ML20100H8411996-02-22022 February 1996 Proposed Tech Specs,Changing TS 3.3.4.1, End of Cycle Recirculation Pump Trip Instrumentation, to Delete SR 3.3.4.1.6 Which Requires RPT Breaker Interruption Time to Be Determined at Least Once Per 60 Months ML20100H7901996-02-22022 February 1996 Proposed Tech Specs,Deleting SR 3.3.8.1.1 Which Requires Channel Check for Loss of Power Instrumentation & Changing TS Table 3.3.8.1-1 to Change Allowable Value for Degraded Voltage Function from 3762V & 3832V to 3876V ML20100H8171996-02-22022 February 1996 Proposed Tech Specs,Changing TS 3.4.11, RCS P/T Limits, to Incorporate Specific P/T Limits for Bottom Head Region of Rv Separate & Apart from Core Beltline Region of Rv ML20100H7741996-02-22022 February 1996 Proposed Tech Specs,Proposing to Revise TS 3.6.5.1, Drywell, to Allow Drywell Bypass Leakage Tests to Be Performed at Intervals of Up to Ten Yrs Based on Demonstrated Performance of Drywell Barrier ML20095G5141995-12-14014 December 1995 Proposed Tech Specs 3.3.1.1, RPS Instrumentation & TS 3.3.6.1, Primary Containment Dwl Isolation Instrumentation to Eliminate Periodic Response Time Testing of Analog Trip Modules ML20095G6401995-12-14014 December 1995 Proposed Tech Specs Instrumentation Associated W/High Pressure Core Spray Sys,Reactor Core Isolation Cooling Sys & Residual Heat Removal Sys ML20095G4791995-12-14014 December 1995 Proposed Tech Specs 3.4.2, Flow Control Valves Re Proposed Deletion of Average Rate of Movement Verification Requirement ML20117E3001995-11-0606 November 1995 Rev 18 to App V Pump & Valve Testing Program Plan ML20094D2031995-10-27027 October 1995 Proposed Tech Specs,Consiting of Changes to TS 3.1.3 to Include 25% Surveillance Overrun Allowed by LCO 3.0.2 Into Allowances of Surveillance Notes for Control Rod Notch Testing Per SR 3.1.3.2 & SR 3.1.3.3 ML20094D2141995-10-27027 October 1995 Proposed Tech Specs,Consisting of Changes to TS 5.2.2.e to Revise Requirements for Controls on Working Hs of Unit Staff That Perform SR Functions ML20085N0621995-06-23023 June 1995 Proposed Tech Specs Bases,Per TS 5.5.11, TS Bases Control Program ML20085F5961995-06-0909 June 1995 Proposed Tech Specs,Incorporating Description of Exclusion Area Boundary ML20087J5691995-05-17017 May 1995 Rev 17 to App V, Pump & Valve Testing Program Plan of CPS ISI Program Manual ML20085J9701995-02-16016 February 1995 Proposed Tech Specs Reflecting Enforcement Discretion Re TS LCO for Div 2 DC Electrical Power Sources 1999-07-06
[Table view] Category:TEST REPORT
MONTHYEARML20067D2051993-11-30030 November 1993 Reactor Containment Bldg Integrated Leak Rate Test,Final Rept U-601847, Reactor Containment Bldg Integrated Leak Rate Test. W/1991-02-28028 February 1991 Reactor Containment Bldg Integrated Leak Rate Test. W/ U-601519, First Refueling Outage Startup Rept1989-08-21021 August 1989 First Refueling Outage Startup Rept ML20116G5411989-06-15015 June 1989 Fuel Matls Technology Test Rept on Determination of Fast Neutron Flux Density & Fluence:Clinton Station for 890614 ML20154N8001988-02-0202 February 1988 Rev a to Qualification Test Rept 110-11004, AMP Insulated Terminals & Splices for Class 1E,Inside Containment Svc in Nuclear Power Generating Stations U-600813, Reactor Containment Bldg Integrated Leakage Rate Test, Final Rept1986-12-31031 December 1986 Reactor Containment Bldg Integrated Leakage Rate Test, Final Rept ML20154L6921986-02-11011 February 1986 Rev 3 to Calculation for Establishing Required Raceway/ Cable Separation Distances ML20199F4291986-01-31031 January 1986 Reactor Containment Bldg Integrated Leakage Rate Test, Final Rept ML20137M1631985-11-0505 November 1985 Rev 2 to Calculations for Establishing Required Raceway/ Cable Separation Distances ML20137M1671985-09-26026 September 1985 Rev 2 to Cable Separation ML20135F2801985-09-11011 September 1985 Rev 0 to SPDS Dynamic Simulation Test Results Rept ML20137M1931985-06-0707 June 1985 Rev 1 to Auxiliary Transformer Metering Classification Change from Class 1E to Associated ML20137M2871985-05-17017 May 1985 Rev 0 to Minimizing Separation Requirements for Cables ML20137M3001985-04-16016 April 1985 Rev 0 to Non-Class 1E Resistors Used W/Westinghouse V-4 Transducers ML20137M2061985-02-26026 February 1985 Rev 1 to 1H22-PO71 & 1H22-P072 Rod Position Indication Sys Multiplexing Cabinets ML20116H5261985-02-22022 February 1985 Unique Encroachments Final Test Rept ML20137M2811985-02-0101 February 1985 Rev 0 to Separation Requirements for Circuits Connected to Class 1E Sources Which Are Deenergized on Accident Signal ML20137M2671985-01-0808 January 1985 Rev 0 to Tray Cover Exemption for Safety Trays Under Non-Safety Raceway ML20137Z8271984-11-30030 November 1984 Nuclear Component Qualification Test Rept Square D 9025-BCW-45 Thermal Switch ML20137M2391984-11-19019 November 1984 Rev 0 to Bus 1A1 or 1B1 Pressure Transmitter Primary & Secondary Fuses ML20137M2151984-10-19019 October 1984 Rev 0 to Failure Effects Mode Analysis on Non 1E Components in Dc Motor Control Ctr 1A,1B & 1D ML20094F5751984-08-0606 August 1984 Production Test ML20094F5641984-05-10010 May 1984 Generic 300 Start Tests for Electro-Motive Div of General Motors (EMD) Model EMD-645E4 Diesels ML20137M1851983-10-17017 October 1983 Rev 1 to Open Circuit of Current Transformer Secondary ML20137M1971983-10-17017 October 1983 Rev 0 to Separation of Class 1E & Non-Class 1E Circuits in IE22-S004 ML20071D0801983-02-18018 February 1983 Masonry Block Wall Tests ML20070E6631982-11-12012 November 1982 Control Sys Failure Review & Evaluation Program, Final Rept ML20063M6051982-09-0909 September 1982 Kuosheng Startup Test Rept,Reactor Internals Vibration Monitoring ML20137M1751982-05-19019 May 1982 Rev 0 to Cable Separation Associated W/Diesel Generators Var Transducers 1993-11-30
[Table view] |
Text
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OPEN CIRCUIT OF CURRENT cue nom 9-BD-9 SARGENT ALUNDY TRANSFORMER SECcNoARY n ., 1 oat.ToJ17/a 3 '
C ' "' ^ ' ' O Xl Listy-R elated 1 N on-S.t e rv -h eiated Page 1 of 8
. c.ent ILLINOIS PCWER COMPANY p,,p., o tofb _,,,(had yr pgD l o,s./cyf r/n _
Protect CLINTON - UNIT 1 g,,,,,,d n, h[ fyd 37en lcate /v//r//)
Pros. No. 4536-00 Ew.u No Approved by My[# [. yer CYO
- l0 ate / !i7!6; f 6SP.)lv' gpg)
U FILE Alo.19'@
I. REVISION STATUS Rev. 0 1/4/83 First issue all pages.
Rev. 1 10/17/83 Second issue all pages. The revised material
~
is denoted by linleftmargin. This revision deletes information from two referenced Q.A.
calculations which have been ' voided, and includes two more pieces of equipment into the analysis.
\ d II. PURPOSE
. The purpose of this calculation is,to determine if the open circuiting of the secondary of the non-Class lE metering or bus duct differential relaying cts at the main and reserve feed to the 4.16 kV ESF switchgear would cause a condition adverse
~
to safety-related circuits, since the non-Class lE CT secondary wiring is bundled and/or in close proximity to C.'. ass lE wiring internal to the switchgears. The open circuiting of the non-a
?+
Class lE cts analyzed are identified in Section IV.B of this 8
, calculation.
E i UNCONTROLLED COPY
~
REVIEW METHOD D c b + l.-l S*
19 [
8601280211 060124 PDR ADOCK 05000461 A PDR
O cs For OPEN CIRCUIT O'P GURRE!!? Caic No 19-DD-5 SARGENT iLUNDY TRANSFORMER SECONDARY H ., 1 0.te10/17 /8 3
- ee.e.e.eems .
"*"C^'*" 8 X l s4:etv-Hetated N on -Sala ty -H eia ted Page 2 of i
. ci.en ILLINOIS POWEP. COMPANY Prepared b, G. A. POLETTO Date/4
/ ///O :
Pro,ect CLINTON - UNIT 1 Reviewed by ? Oase :
Proi. No. 4536-00 Epp No. Approved by Date III. REFE RENCES ~
- 1. " Peak Voltages Induced by Accelerated Flux Reversal in.
Reactor Cores Operating Above Saturation Density" by Theodore Specht and E. C. Went: in AIEE Transactions, May 1946, 2 Insulation of Electrical Apparatus book by D. F. Miner, 1941, Chapter III, " Factors Affecting Dielectric Behavior".
- 3. "Overvoltages in Saturable Series Devices" by A. Boyajian and G. Camilli in AIEE Transactions, 1951, pp. 1845-1853 4 ANSI Standard C57.13-1978
- 5. ICEA-NEMA Standard S-66-524,
- 6. Q A. Calculation 4536-EAD-1, Rev. 2, dated 8/12/81.
l7 S&L single line drawing: E02-1AP01, Sht. 004, Rev. C, 4/29/83 .
8 S&L Relay and Metering Diagrams:
E02-1AP12, Sheet 011, Rev. P , dated 4-7-8 3
' E02-1AP12, Sheet 013, Rev. M, dated 4-7-83.
E02-1AP12, Sheet 016, Rev. J, dated 7-22-83 s 9. S&L CT excitation curves:
Westinghouse 459341, Rev. A, for 5000:5A CT' 8
a a Westinghouse 536932-A, Rev. A, for 800:5A CT .
j Westinghouse 622004, Rev. A, for 4000:5A CT I Westinghouse 666818, for 2500:2.5A CT.
- 10. Memo of telephone conversation between Ed Horn of Westinghouse and G. A. Poletto of S&L, dated 12/30/82
- 11. NCRs 5426; Rev. 1, dated 8-9-82 5425, Rev. 1, dated 8-9-82 5453, Rev.,1, dated 8-9-82.
C.io Fo, OPEN CIRCUIT Or CURRENT coc so 19-BD-5 SARGENT a LUNDY TRANSrORMER SECONDARY a .. 1 a.ie 10/17/a 3
-.... .=._ ,
" ~ - + - x i wei,-sei.i.o =l]- ! N . -ue .-a.i.i.a r.y. 3 or 8 C1ent ILLINOIS POWER OMPANY Prewed by ' G. A. POLETTO cai.fc4 y /G Proiect CLINTON - UNIT l Reviewed av 0.te Proi. No. 4536-00 Em.ip No. Approud av Oais III. REFERENCES (Cont'd.)
- 12. ANSI /IEEE C37.90-1978, " Relays and Relay-Systems Associated .
j with Electric Power Apparatus".
h 13. "The Effects of Electric Discharges Between Electrodes Across Insulation Surfaces", by Lyon Mandelcorn, AIEE Transaction on Power Apparatus and System, August 1961, pp. 481-494
- 14. Buchanan "Electrolog" January 1971 IV. DATA A. Test Data on Some Typical cts l.(Reference 1, dated 1946)
- a. 2500/5A CT Voltage Class 5000V Westinghouse Type H-5
) Accuracy Class 0.3D-0.1, 0.5, 2 Peak secondary open circuit voltage with rated current in the primary: v oc = ll,000V i
1 b. 5/5-600/5A CT voltage Class 5000V Westinghouse Type. CT-5 i Accuracy Class 0. 38-0.1, 0.5, 2 i
Peak secondary open circuit voltage with rated current 4
in the primary: V oc = 1800V
}z 8 2 (Reference 10, dated 12/30/82) i m l 3 a. 1200/5A CT Westinghouse Type RCT for medium voltage swgr.
! ! Peak secondary open circuit voltage with rated current
- in the primary
- V = 25,000V oc i
, b. 600/SA CT Westinghouse Type RCT for medium voltage swgr.
1 i Peak secondary open circuit voltage with rated current in the primary: V = 12,000V oc
- c. 400/5A CT Westinghouse Type RCT for medium voltage swgr.
Peak secondary open circuit voltage with rated current in the primary: V = 4000V' oc l
Cales Fo, OPEN CIRCUIT OF CURRENT _
caic No 19-BD-5 SARGENT LUNDY TRANSFORMER SECONDARY
.~.~..... s ev i c.ivi o/17 /s I"*"
X l S.teiv-Reiated jp j , Nun-Salety-Hetated
! Page 4 of 8 Ci.en II.LINOIS POWER COMPANY buared by G. A. POLETTO Date/OS 7/;'l Prsiect CLINTON - UNIP 1 Reviewed by Date Prea No. 4536-00 duu.o No awroved o< oei.
IV. DATA (7ont'd.)
S. Rating of Existing Non-Class lE cts Whose Open Circuiting is Analyzed
- 1. On the Main Feed to 4.16 kV Buses lAl and 1B1 (Ref. 9 )
- a. 2500-2.5A CT with accuracy class C-400 for bus duct differential relay,
- b. 800-5A metering CT with accuracy class 10H50,
- 2. On the Reserve Feed to 4.16 kV Buses lAl and 1B1 ( Re' f . 9 )
4000-5A CT accuracy class C-200 for bus duct differential" relay.
- 3. On the Main feed to 4.16 kV Bus ICl 5000-5A CT for bus duct differential relay.
- 4. On the Reserve Feed to 4.16 kV Bus 1Cl 4000-5A CT for bus duct differential relay.
C. Insulation Requirements for the cts, Cables and Other Devices
- 1. A current transformer is required to withstand a secondary voltage of 3500V peak for 60 seconds (per ANSI C57.13 -
, Ref. 4 ),
a I 2 600V class cables are required to withstand 3500V rms for
! 5 minutes (per ICEA-NEMA Std S-66-524 - Ref.5). '
?.
j 3. Terminal blocks and test switches are required to withstand twice rated voltage plus 1000V rms for 60 seconds.
Terminal block rated 750V (Ref. 12, p. 42) 750 x 2
- 1000 = 2500V rms Test switch rated 600V 600 x 2 + 1000 = 2200V rms l
l
con so,
~~
OPEN CIRCUIT OF CURRENT k cm. N o_ 19-BD-5 SARGENT a LUNDY TRANSPOnnEn SECONDAaY ---
n e, 1 o. .t on 7 /s ,
....,~. .. ,
- "C"" X,. Safety-Hetated , Non-S.tety-netated Pa9e 5 of 8 I. (
, ct..n ILLINOIS POWER COMPANY Preparea bv G. A. POLETTO Date/c/f 7/C Proiect CLINTON - UNIT 1 nes,ewea av lcate Approved by Date Proi. No. 4536-00 Euwo No.
V. ANALYSIS OF EFFECTIVE OPEN CIRCUITED CT SECONDARY Determination of the peak voltage that would occur if.the secondary of any of these cts in question were to become open circuited with full load current flowing in the primary with any degree of accuracy is difficult without actually performing a test on each CT. This peak voltage is a function of the turns ratio and the design of the core of the transformer.
Even with,the same turns ratio, the peak voltage may vary greatly from one CT to another due to differences in the core design. Since the manufacturers are reluctant to perform tests on cts with secondaries open circuited, there is very limited test data available to'compa're with the cts in question. liowever, it can be seen from the available test data that the peak voltages may range from 2 kV to 25 kV. If the open circuit ;
of ,the secondary goes undetect'ed for an extended period of ,
time, these peak voltages will most likely cause an insulation failure.
From the industry requirement for the insulation of the devices j given in Section IV.C, and that breakdown voltage' for insulation, materials is an inverse exponential function of time (Ref. 2 ) ,
~
[ we may draw a typical curve for each of the four insulations
$ involved in the CT circuitry as shown below.
E
I ge,p,OPEN CIRCUIT OF CURRENT caic Na 19-DD-5 l SARGENT x LUNDY TRANSFORMER SECONDARY R ev.
1 04teLO/17/8 3
.~..~. ._ ,
j
" * * * * " N; Listv-Re64:ed Non-Lf ety-R elated Paqe 6 of 8 ct.en: ILLINOIS POWER COMPANY prepared by G. A. POLET10 Data /od V5'3 '
Pro,ect CLINTON - UNIT 1 R viewed bv l cate l Pro No. 4536-00 Ecu.o No. Apo,oved bv l 0 ate V. ANALYSIS OF EFFECTIVE OPEN CIRCUITED CT SECONDARY (Cont'd.)
3 ,_
CABLE l
i N
o
) I t
c E$
< k N l
3.5 x 4 kV 2.5kV x d 0 I 3 2.2kV x d Term.,Blk.
1 Min.
. Test /
Switch ,
i
. LOG TIME -
i From this figure we can. expect either the CT insulation, the terminal block or the test switch to fail before the cable
, insulation. If the CT fails, it would occur near the ungrounded j j CT terminal which is exposed to the full peak open circuit voltage j and would most probably involve a sparkover between terminals or to
- ground. The arc will quickly form a carbon track (Ref.13) which will j j provide a low resistance path to ground. !!avina both te.rminals ground +
2 will short circuit the secondary of the CT and alleviate the i high peak voltage. The secondary current will only be a few amperes and will not cause damage to the ground path.
The safety and non-safety terminal blocks or test switches are physically separated (not touching) from each other. If the I . terminal block or test switch fail, it will involve an arc from
I w ro, - OPEM CIRCUIT OF CURRENT Cale. Na 19-0D-5
. SARGENT2 LUNDY TRANSFORMER SECONDARY Rev 1 Due10 /17 /9 -
-speer . -
1 * " " * * '
y Xf Ltet y-Related N on-Liet y-Related Page 7 of 8 h
ct.en ILLINOIS POWER COMPANY Prep.,ed by G. A. POLETTO Oue/GId?3
[
Que f
) he,u CLINTON - UNIT 1 Reve*ed b, I ho,. No. 4536-00 Ewa No. Approved av om i
k V. ANALYSIS OF CFFECTIVE OP.':N. CIRCUITED CT SECONDARY (Cont'd.) f l :
i the terminal connected to the ungrounded CT lead to the grounded . r terminal. This are will quickly form a carbon track (Ref. 13) which will act as a low resistance path for the CT secondary current. This short circuits the secondary of the CT and alleviates the high peak voltage. The secondary current will l
I only be a few amperes and will not cause damage 'in the ground path.
)/
r
~
l For the metering cts the open circuit condition would be detected
- during the next meter logging operation and corrected.
I l
' For the main (RAT) feed differential relay CT to any of the ESF f buses, the differential relay will trip immediately and transfer the ESF buses to the reserve source or the diesel generator if l
4 the current through the open circuited CT is greater than the minimum sensitivity of the relay. However, if the current is I
less than the minimum relay sensitivity, open circuiting of the CT will not cause the breaker to trip but the relay will
! still be able to detect and trip for any f ault occurring. within its zone of protection.
- For the reserve feed differential relay CT to any of the ESF e
buses, the dLfferential relay will trip immediately and transfer 4 .
i o 8
1 i
} the ESF busea to the main source or the diesel generator if ;
.j the current through the open circuited CT is greater than the ,
a j minimum sensitivity of the relay. If the current is less than j the minimum relay sensitivity, open circuiting of the CT will i not cause the breaker to trip, but the relay will still be >
able to detect and trip for any fault within its zone of l
j -
protection.
1
)
- ** Ca. ra, OPEN CIRCUIT OF CURRENT caic. g. 19-BD-5 i
i SARGENT ELUNDY TRANSFORMER SECONDARY Rev 1 Oa:JO/17/03 l - .co m .
8 c"<^"" - X! s.t.t,-a. tar d Non-Saf ety- A elated Page8 of 4
l
- ILLINOIS POWER COMPANY Pre w ed bv G. A. POLETTc Date/d ///b3 client l l Date Pro,ect CLINTON - UNIT 1 Rev.evoed by 1
. 1 Equ.o No. Approved bv l Date i
! Prai No. 4536-00 !
i
., VI. CONCLUSIONS r i
We conclude that open circuiting of the metering or differential [
i relaying cts is not expected to result in a condition adverse to i safety-related circuits.
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