PLA-2089, Final Deficiency & Part 21 Repts Re Safety Parameter Display Sys Technology Energy Corp Model 156 Isolators.Initially Reported on 840106.Non-IE Power Supply Will Be Provided for Isolator Prior to End of First Refueling
| ML20087H738 | |
| Person / Time | |
|---|---|
| Site: | Susquehanna  |
| Issue date: | 02/27/1984 |
| From: | Curtis N PENNSYLVANIA POWER & LIGHT CO. |
| To: | Murley T NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| References | |
| REF-PT21-84 PLA-2089, NUDOCS 8403210145 | |
| Download: ML20087H738 (4) | |
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x+ PP&L Pennsylvania Power & Light Company Two North Ninth Street
- Allentown, PA 18101
- 215 1 770'5151
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,s Norman W. Curtis .
Vice President-Enginecting& Construction-Nuclear
,4 215/770-7501
^ FEB 271984 - -
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3.Dr. Thomas E. Hurley
,~ Pegional Administrator, Regioa.I
. U.S. Nuclear Regulatory _Comruission
'631 Park Avenue: ( i lrini of Prussia, PA ,19406
~ SUSQUEHANNA STEAM ELECTRIC STATION s
FINAL REPORT ON : A = DEFICIENCY INVOLVING
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1N, iSPDS TEC MODEL^156(ISOLATORS ER 1D050,8' '; .b FILE 821-10 PLA-2089 ~ '
, Docket No. 50-388 LReferenceA (1) PLA-2063 dated 2/06/84
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Dear Dr. Murley:
O 1s letter serves =to provide.the Commission with a final report on a deficiency initolving SPDS'TEC Model 156 isolators. This deficiency was
. freported. under'10CFR50.55(e)'by telephone to'Mr. G. Kelley of NRC Region I by g p Mr. J. Saranga'of PP&L on January 6, 1984.
e ' 'The attachment to this letter contains=a description of the problem, the.
safety-implications,-and the corrective actions.. This deficiency was addressed for' Unit'1 in PLA-2070 dated 2/03/84.(LER 84 003).
, Since Ehe~ details of this report Trovide information relevant to the reporting "requireme'nts of'10CFR21 for Unit 2, this correspondence is considered to also L, discharge any. formal responsibility PP&L may have for reporting in compilance thereto. .
I' We trust thelCommissien will find this report to be satisfactory,
- Veryj truly ' yourr,,4
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- N. W. Curtis h '
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" Vice President-Engineering & Construction-Nuclear
~ VAtrachment-
?.. f Y 8403210145 840227
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PDR ADOCK 05000388 g-hS PDR y L
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Page 2 SSES PLA-2089 FEB 27 m ER 100508 Pii. 821-10
'Dr. Thomas E. Murley I
'_. Copy to: .
-Mr.1 Richard C. DeYoung'(15)'
Director-Office of Inspection & Enforcement u U.S. Nuclear-_ Regulatory Comuission
. Washington, D.C. 20555-
-Mr. G.; Mcdonald,_ Director Office of Management:Information & Program Control
- U.S.: Nuclear Regulatory Commission Washington, D.C.--20555 Mr. R. H. Jacobs U.S. Nuclear Regulat'ory Commission
-P.O.. Box 52
- Shickshinny, PA 18655 Records Center.
Institute.of Nuclear. Power Operations liOO; Circle.75 Parkway,-Suite 1500 Atlanta, GA'30339 s
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FINAL REPORT v ,, .
, ' Attachment [ to PLA-2089 1
' SUBJECT l Technology for Energy Corporation Model 156 isolators procured under Bechtel
-Purchase Order 8856-J-049-AL-do not meet the requirements of the purchase sspecification which calls for ceparation of the power source from both'the y
- input land' output signal connections. Two instances have been identified where a Class!1E power source:isLused tesulting'in'a violation in separation 1 requirements..
g iDESCRIPTION'
!Th$ safety' parameter' display system (SPDS) and the interim emergency response
' computer system (ERCS) '(both non-1E) require input. from safety related.
. systems.- 'To provide separation'for the safety related systems, TEC Model 156 isolators were purchased and installed. The purchase order for these isolators; required a minimum isolation of 600 VAC or 1000 VDC between the
- input, output, and power' supply circuits. After the installation of the
- Isolators, ~it was discovered that the power supply circuit was directly v> connected to the output circuit. Consequently, use of the isolator in
- cabinets with -1E power' results in' connection of a 1E s ource to a non-1E =
. circuit..- Two cases have been identified where a Class-1E power supply was
- used for the isolator
l'. -average power range monitor.(APRM) inputs-to SPDS
- 2. , high' pressure coolant injection (HPCI) inputs to interim ERCS dANALYSIS OF SAFETY IMPLICATIONS-The. configuration at'the isolators on the APRM inputs to SPDS could have led 1to the failure.of the-20 VDC power' supplies in all six APRM channels. These q ? power supplies.also serve'as;the power source for the relays that provide a
, , ' trip , signal to the' RPS systera. . A fault within the SPDS system could propagate
- through the: isolator and cause'the relays to.deenergize. When the relays
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- deenergize, a, reactor scram is initiated.
w, iThe power supply 'for: the isolator on the HPCI system input to interim ERCS is .
, also usedlas.the power. supply for the HPCI control loop.. Consequently, a
' failure originating in the interim ERCS system could have caused the loss of the HPCI control loop power ~ supply. Without the~HPCI control loop, HPCI would
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A 3 be inoperable.L
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tin both deficiencies: discussed above, there is adequate protection on the Class"1Eipowerl supplies to prevent their failure from propagating and a f Laffecting'ad:litional safety related functions, u-
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,j ~-CORRECTIVE' ACTIONS
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- M, ; Unit 1^;&' Common:
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[~ -((1)lThepower.. supply lon-theisolatorforHPCIinputstointerimERCSis _.
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- disconnected.1 A non-1E power. supply-will'be provided for the isolator by vg y 7 PMR 84-3011 prior;to;the-endlof-the first" refueling outage.
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I[.1 [(2) Afnon-1E power; source has been.provided for the' isolator'on the APRM p ,
inputs to',SPDS under DCP 82-174C, Rev.-5.
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(3) The remaining Unit.1 and common-TEC Model 156' isolators procured under
. Purchase;0rder-8856-J-049-AL were reviewed by an' examination of the design "y :g '
- drawings;and/or a. field inspection.-- This review ~is~ documented under NCR-84-026.-
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Iq. M ;;(1) A.non-lE power supply will;be'provided for the isolator on HPCI inputs to m
~ .. interim-ERCS. prior to initial 1 criticality under PMR 84-3048.
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' ' ' - " -(2)fAJnon 1EJpower. supply-will be'provided.for the isolator on the APRM inputs
.-to SPDS' prior.to fuel load.. This-work is being done under NCR 83-1110 and lNCRl83-1174.
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-(3)..Th'e7 remaining Unit 2 TEC'Model 156 isolators procured under Purchase Order i
8856-J-049-AL will be reviewed by'an examination of the design drawings-
,~~ y. - and/orra field. inspection."1This review will'be documented under NCR n
027..
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