ML20078B871

Part 21 Rept Re Failure of Automatic Depressurization Sys Initiation Due to Blown Fuses.Digital Signal Conditioner Printed Circuit Cards Used in Nuclear Protection Sys Basic Components Involved.Cards Mfg by GE

ML20078B871
Person / Time
Site:	Clinton
Issue date:	09/19/1983
From:	Hall D ILLINOIS POWER CO.
To:	James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
REF-PT21-83-988-000 1606-L, PT21-83-988, PT21-83-988-000, U-10091, NUDOCS 8309270288
Download: ML20078B871 (8)

Text

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y 1606-L ILLINOIS POWER 00MPANY U-10091 CUNTON POWER STATION. P.O. BOX 678. CLINTON. ILLINOIS 61727 September 19, 1983 Docket No. 50-461 Mr. James G. Keppler Regional Administrator, Region III U.S. Nuclear Regulatory Commission 799 Roosevelt Road Glen Ellyn, Illinois 6013/

Subject:

10CFR PART 21 DEFECT ADS DIGITAL SIGNAL CONDITIONER CARD FUSE FAILURES

Dear Mr. Keppler:

On July 21, 1983 Illinois Power Quality Assurance (IFQA) received a Potential Defect or Noncompliance (10CFR21) Referral from Nuclear Station Engineering Department (NSED) concerning the failure of automatic depressurization system (ADS) initiation due to blown fuses. Based on an evaluation, Illinois Power is providing the following information to the Commission in accordance with the requirements of 10CFR Pair 21.21 (b) (3).

(i) D. P. Hall, Vice President of Illinois Power Company, by means of this report, hereby informs the Commission of a 10CFR Part 21 defect.

(ii) The basic components involved are digital signal conditioner (DSC) printed circuit cards used in the Nuclear System Protection System (NSPS). A list of the NSPS printed circuit cards by parts list (PL) number, title, and abbreviation is included with this report as Attachment "A".

(iii) The NSPS printed circuit cards were manufactured and supplied by:

General Electric Compaay Nuclear Power Systems Division 175 Curtner Avenue San Jose, CA 95125 (iv) During construction and initial operation (C&IO) testing, the ADS logic failed to actuate the safety relief valves in response to automatic or manual signals. The failure was attributable to a blown fuse (F3) on the DSC card. When fuse F3 blows, a card-out-of-file signal is annunciated in the main SEP 221983 8309270288 830919 PDR ADOCK 05000461 -

S PDR [

s Mr. James G. Keppler Page 2 September 19, 1983 control room, and the power-on-initialization logic is prevented from initiating the ADS function in that division.

The ADS is an engineered safety feature subsystem of the emergency core cooling system. ADS provides pressure relief during a loss of coolant accident in which the high pressure core spray fails to provide a sufficient volume of water to the reactor, and allows the low pressure core spray system to successfully cool the reactor vessel. The blown fuse on the DSC card would result in a deficiency in the function of the ADS and could, under operating conditions or an operating ,

transient, contribute to the exceeding of a safety limit. In consideration of an independent single failure, a blown fuse on the ADS card could result in loss of a safety function necessary to mitigate the consequences of an accident.

(v) NSED informed IPQA, by means of the Potential Defect or Noncompliance (10CFR21) Referral on July 21, 1983, of a potentially reportable defect in the ADS initiation logic.

(vi) A list, showing the number and location of each type of NSPS printea circuit card at Clinton Power Station, is included with this report as Attachment "B".

(vii) Investigation has revealed the cause of the fuse failures to be attributable to GE's assignment of pins in the card edge connector. Card edge connector (P2) pin (P2-21, u) provides a fault path to the card out-of-file interlock signal present at pin (P2-22, v).

When the card edge connector (P2) is either connected to, or disconnected from the card, pins (P2-21, u and P2-22, v) momentarily short and the subsequent fault I current is sufficient to open the fuse on the DSC card.

The NSPS printed circuit cards have been returned to GE in San Jose, CA. GE will implement FDDR No. LH1-777 to replace fuse F3 on each DSC circuit card with a 2.2 Kchm resistor to limit the power bus load to 5.5 mA.

This work is expected to be completed by September 23, l

1983. A subsequent test of each card by the Terradyne l

card tester is expected to be completed by GE by February 1, 1984.

All other printed circuit cards in the NSPS panels will be reviewed (schematically) by Illinois Power (NSED) for edge connector pin assignments for all fused signal paths. Completion of this action is expected by December 1, 1983.

l (viii) Not applicable l

Mr. James G. Keppler Page 3 September 19, 1983 Our evaluation of this reporta'ule defect is available for your review at our offices. I trust that this letter provides sufficient information for your review and analysis of the problem and solution.

Sincerely yours d

D. P. Hall Vice President KFH/j f Attachments cc: U.S. NRC Resident Office Illinois Department of Nuclear Safety Director of Inspection and Enforcement (3 copies)

INPO Records Center

Mr. James G. Keppler U-10091 September 19, 1983 Attactunent A LIST OF NSPS PRINTED CIRCUIT CARDS, PARTS PARTS LIST LIST ITEM ABBRE- ITEM ABBRE-NO. TITLE ,VIATION NO. TITLE VIATION 600 CARD SELECT DCDR CSD 634 RESID HEAT REMOVAL SYS 4 RHR-4 601 DATA ACQ/DSPL CONT DADC 635 RESID HFAT REMOVAL SYS 5 RHR-5 602 DISPLAY AND CONTROL DCP 636 RESID HEAT REMOVAL SYS 6 RHR-6 603 ANLG TRIP MDL ATM 637 RESID HEAT REMOVAL SYS 7 RHR-7 604 DGTL SIG CONDITIONER (24VDC IN) DSC 638 REAC CORE ISLN CLG SYS 1 RCIC-1 605 DGTL SIG CONDITIONER (120VAC IN) DSC 639 REAC CORE ISLN CLG SYS 2 RCIC-2 605A DGTL SIC C0hDITIONER (120VAC IN) DSC 640 REAC CORE ISLN CLG SYS 3 RCIC-3 606 2/4 LOGIC 2/4 LOGIC 641 REAC CORE ISLN CLG SYS 4 RCIC-4 607 REAC PROTECTION SYS 1 RPS-1 642 REAC CORE ISLN CLG SYS 5 RCIC-5 608 REAC PROTECTION SYS 2 RPS-2 643 REAC CORE ISLN CLC bYS 6 RCIC-6 609 REAC PROTECTION SYS 3 RPS-3 645 1-999 SEC TD TD1-999 610 REAC PROTECTION SYS 4 RPS-4 648 ISOLATED LANP DRVR ILD 611 REAC PROTECTION SYS 5 RPS-5 650 TWO WAY BUFFER 2WB 612 REAC PROTECTION SYS 6 RPS-6 668 CARD SELECT MON CSM 613 REAC PROTECTION SYS 7 RPS-7 671 STC-CPU MEMORY CPU MF,M 614 NUC ST SPLY SHUT 0FF SYS 1 NS4-1 672 SELF TEST CONT UNIV I/O UNIV I/O 615 NUC ST SPLY SHUT 0FF SYS 2 NS4-2 673 SER I/O MEMORY SER I/O 616 NUC ST SPLY SHUT 0FF SYS 3 NS4-3 679 PWR SPLY MON PWRM 617 NUC ST SPLY SHUT 0FF SYS 4 NS4-4 682 NUC ST SPLY SHUT 0FF SYS 8 NS4-8 618 NUC ST SPLY SHUT 0FF SYS 5 NS4-5 684 AUTO DEPRESSURIZATION SYS 5 ADS-5 619 NUC ST SPLY SHUT 0F'. SYS 6 NS4-6 685 AUTO DEPRESURIZATION SYS 6 ADS-6 620 NUC ST SPLY SHUT 0FF SYS 7 NS4-7 687 2 WAY SIG SEPARATION 2WSS 621 AUTO DEPRESSURIZN; ION SYS 'i ADS-1 688 SELF TEST CONT. MOTHER STCMTH 622 AUTO DEPRESSURIZATION SYS 2 ADS-2 695 LOAD DRIVER LD 623 AUTO DEPRESSURTZATION SYS 3 ADS-3 951 ANALOG INP ISOLATOR AII 624 AUTO DEPRESSURIZATION SYS 4 ADS-4 952 ANALOG ISOL POWER SUP AIPS 625 LOW PRESS CORE SPRAY SYS 1 LPCS-1 954 FIELD CONTACT ISOLATOR FCII 626 LOW PRESS CORE SPRAY SYS 2 LPCS-2 955 HI SPEED INP ISOLATOR HSII 627 LOW PRESS CORE SPRAY SYS 3 LPCS-3 958 12V LOGIC INP ISOLATOR LII 628 HICH PRESS CORE SPRAY SYS 1 HPCS-1 960 ANALOG OUT ISOLATOR A01 629 HIGH PRESS CORE SPRAY SYS 2 HPCS-2 962 HIGH LEVEL OUT ISOLATOR HLOI 630 HIGH PRESS CORE SPRAY SYS 3 HPCS-3 963 FLOATING LOW LEVEL OUT ISOLA. FLLOI 631 RESID HEAT REMOVAL SYS 1 RHR-1 964 12V LOGIC OUT ISOLATOR LOI 632 RESID HEAT REMOVAL SYS 2 RHR-2 965 HIGH SPEED OUT ISOLATOR HSOI 633 RESID HEAT REMOVAL SYS 3 RHR-3 986 INVERTING HIGH LEVEL ISOLA. IHLOI l

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Mr. James G. Keppler U-10091 Attachment B Page 1 of 4 NUMBER AND LOCATION OF NSPS PRINTED CIRCUIT CARDS, BY TYPE P.L.

ITEM PANEL NO. ASSEMBLY CARD TYPE P661 P662 P_663 P664 TOTAL 600 147D8456 G002 Card Select Decoder 8 7 4 3 22 601 147D8454 G001 Data Acq/Dspl Cont. I 1 1 1 4 603 147D8505 G001 ATM 64 52 26 17 159 604 147D8461 C001 Digital Signal Conditi 22 2G 8 7 57 605 147D8461 C002 Digital Signal Conditi 15 14 3 2 34 605A 147D8461 C003 Digital Signal Conditi 4 3 1 1 9 606 147D8503 G001 2/4 Logic 6 6 6 6 24 607 147D8463 G001 RPS #1 1 1 1 1 4 608 147D8464 G001 RPS #21 1 1 1 1 4 609 147D8465 G001 RPS #3 1 1 1 1 4 610 147D8466 G001 RPS #4 1 1 1 1 4 611 147D8467 G001 RPS #5 1 1 1 1 4 612 147D8468 G001 RPS #6 1 1 1 1 4 613 147D8469 G001 RPS #7 1 1 1 1 4 614 147D8470 G001 NS4 #1 1 1 1 1 4 615 147D8471 G001 NS 4 #2 1 1 1 1 4 616 147D8472 G001 NS4 #3 1 1 1 1 4 617 147D8473 G001 NS4 #4 4 4 0 0 8 618 147D8474 G001 NS4 #5 1 1 0 0 2 619 147D8475 G001 NS4 #6 1 1 0 0 2 620 147DB476 G001 NS4 #7 1 1 1 1 4 021 147D8478 G001 ADS #1 1 1 0 0 2 622 147D8479 G001 ADS #2 2 2 0 0 4 623 147D8480 G001 ADS #3 2 2 0 0 4 624 147D8481 G001 ADS #4 1 1 0 0 2 625 147D8484 G001 LPCS #1 1 0 0 0 1 626 147D8485 G001 LPCS #2 1 0 0 0 1 627 147D8486 G001 LPCS #3 1 0 0 0 1 628 147D8500 G001 HPCS #1 0 0 1 0 1

Mr James G. Keppler U-10091 Attactunent B Page 2 of 4 NLhBER AND LOCATION OF NSPS PRINTED CIRCUIT CARDS, BY TYPE P.L.

ITEM PANEL N3. ASSEMBLY CARD TYPE P661 P662 P663 P654 TOTAL 629 147D8501 G001 HPCS #2 0 0 1 0 1 630 147D8502 G001 HPCS #3 0 0 1 1 2 631 147D8487 G001 RHR #1 1 1 0 0 2 632 147D8488 G001 RER #2 1 1 0 0 2 633 147D8489 G001 RHR #3 1 1 0 0 2 634 147D8490 G001 RHR #4 1 1 0 0 2 635 147D8491 G001 RHR #5 1 1 0 0 2 636 147D8492 G001 RHR #6 0 1 0 0 1 637 147D8493 G001 RHR #7 1 1 0 0 2 638 147D8494 G001 RCIC #1 1 0 0 0 1 639 147D8495 G001 RCIC #2 1 0 0 0 1 640 147D8496 G001 RCIC #3 1 0 0 0 1 641 147D8497 G001 RCIC #4 1 0 0 0 1 642 147D8498 G001 RCIC #5 0 1 0 0 1 643 147D8499 G001 RCIC #6 2 1 0 0 3 645 147D8504 G001 1-999 Sec Time Delay 9 10 2 2 23 648 219B5378 C001 Isolated Lamp Driver 9 9 3 2 23 650 167B2820 G001 Two Way Buffer 13 9 6 5 33 668 147DE 33 G001 Card Select Mon (CSM) 1 1 1 1 4 668A 147D8453 G002 Card Select Mon (CSM) 1 1 1 1 4 668B 147D8453 G003 Card Select Mon (CSM) 1 1 1 1 4 668C 147D8453 G004 Card Select Mon (CSM) 1 1 1 1 4 668D 147D8453 G005 Card Select Mon (CSM) 1 1 1 1 4 668E 147D8453 G006 Card Select Mon (CSM) 1 1 1 1 4 668F 147D8453 G007 Card Select Mon (CSM) 1 1 1 1 4 668G 147D8453 G008 Card Select Mon (CSM) 1 0 0 0 1 668H 147D8453 G009 Card Select Mon (CSM) 1 1 0 0 2 668J 147D8453 G010 Card Select Mon (CSM) 1 1 0 0 2

o Mr. James G. Keppler U-10091 Attaciunent B Page 3 of 4 NUMBER AND LOCATION OF NSPS PRINTED CIRCUIT CARDS, BY TYPE P.L.

ITEM PANEL NO. ASSEMBLY CARD TYPE P661 P662 P663 P664 TOTAL 668K 147D8453 G011 Card Select Mon (CSM) 1 1 0 0 2 668L 147D8453 G012 Card Select Mon (CSM) 1 1 0 0 2 668M 147D8453 G013 Card Select Mon (CSM) 1 1 0 0 2 668N 147D8453 G014 Card Select Mon (CSM) 1 1 0 0 2 668P 147D8453 G015 Card Select Mon (CSM) 1 1 0 0 2 668S 147D8561 G001 Card Select Mon (CSM) 1 1 1 1 4 66BT 147D8561 G002 Card Select Mon (CSM) 1 1 1 1 4 668U 147D8561 G003 Card Select Mon (CSM) 1 0 1 1 3 668V 147D8561 G004 Card Select Mon (CSM) 1 1 1 0 3 668W 147D8561 G005 Card Select Mon (CSM) 1 1 0 0 2 668X 147D8561 G006 Card Select Mon (CSM) 1 - 1 0 0 2 668Y 147D8561 G007 Card Select Mon (CSM) 1 1 0 0 2 668Z 147D8561 G008 Card Select Mon (CSM) 1 1 0 0 2

! 671 147D8507 G001 CPU Memory 1 0 0 0 1 671A 147D8507 G002 CPU Memory 0 1 0 0 1 671B 147D8507 G003 CPU Memory 0 0 1 0 1 671C 147D8507 C004 CPU Memory 0 0 0 1 1 672 147D8452 G001 Self Test Cont Univ I/O 1 1 1 1 4 672A 147D8452 G002 Self Test Cont Univ I/O 1 1 1 1 4 672B 147D8452 G003 Self Test Cont Univ I/O 1 1 1 1 4 l 672C 147D8452 G004 Self Test Cont Univ I/O 1 1 1 1 4 1

672D 147D8452 G005 Self Test Cont Univ I/O 1 1 1 1 4 l 672E 147D8452 G006 Self Test Cont Univ I/O 1 1 1 1 4 673 219B5376 G001 SER I/O Memory 1 0 0 0 1 l

673A 219B5376 G002 SER I/O Memory 0 1 0 0 1 l 673B 219B5376 G003 SER I/O Memory 0 0 1 0 1

! 673C 219B5376 G004 SER I/O Memory 0 0 0 1 1 679 147D8450 G001 Power Monitor 2 2 2 2 8 l

_. . . . . _ _ = - - - -_. . _ - .

1 Mr. James G. Keppler U-10091 Attachment B Page 4 of 4 l NUMBER AND LOCATION OF NSPS PRINTED CIRCUIT CARDS, BY TYPE t

P.L.

ITDI PANEL NO. ASSEMBLY CARD TYPE P661 P662 P663 P664 TOTAL t

682 147D8477 C001 NS4 #8 1 1 0 0 2 684 147D8482 G001 ADS #5 1 1 0 0 2

685 147D8483 C001 ADS #6 1 1 0 0 2 687 147D8460 G001 2 Way Signal Sep 5 5 2 1 13 695 147D8455 G001 Load Driver 45 40 11 6 102 951 204B6208AA G003 Analog Input Isol 7 5 2 0 14 952 198B6203AA G004 Isolator Power Supply 12 10 4 0 26 954 204B6186AA G004 Field Contact Input Isol 15 13 7 4 39 955 204B6198AA G002 High Speed Input Isol 4 4 6 6 20 958 147D3458 G001 12V Logic Input Isol 42 43 37 38 160 960 204B6220AA G002 Analog Output Isol 7 5 2 0 14

962 204B6188AA G002 High Level Output Isol 27 21 14 11 73 I 198B6241AA 37 963 G004 Floating Low Lvl Out Isol 14 12 6 5 i 964 147D8459 G001 12V Logic Output Isol 10 17 21 23 71 965 204B6196AA G002 High Speed Output isol 4 4 6 6 20 986 147D8457 G001 Inv H/Lvl Isolator 6 6 3 3 18 147D8506 C001 Display and Control 1 1 1 1 4 424 383 217 182 1206 l

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