ML20134B742

From kanterella
Jump to navigation Jump to search
Event Tracking & Followup Assignment Sheet of 951106 Event Re Region Draft Info Notice Discussing Series of Difficulties at Plant W/Square D Series 8501 KPD-13 Relays Installed in RS11 Sockets
ML20134B742
Person / Time
Site: Saint Lucie NextEra Energy icon.png
Issue date: 03/08/1996
From: Hodge V
NRC
To:
Shared Package
ML20134B255 List:
References
FOIA-96-485 NUDOCS 9605300137
Download: ML20134B742 (4)
v • d • e


Text

{{#Wiki_filter:. -. .. ~. ~. G CEAR EVENT TRACRIN3 SEEET No Sort Specified QUERY > "HODGE" $ Assigned To & Assigned Date >= 01/19/96 & Assigned Date <- 01/19/96 i Pltat INFO NOTICE AUTH0 Unit Engineer: H0DGE V. Ev02t 11/06/95 Morning Reports Eriefing 50.72#3 0 LER# 050000009600000 PN#: Cth2r Notification: DRAIT IN FR REGION 2 (1/11/96) a Sycteas Component OP5 EATING MODE SIGNIFICANCE t 1 - Operation A - Reactor Protection System 2 - Startup B - Safety Related Cooling System i 3 Hot Standby C - Ebel Cladding 4 - Hot Shutdown D - Reactor Coolant Pressure Boundary 5 - Cold Shutdown IL-Containment 6 - Refueling 67-Plant Power j 7 - Other n/r ded.ka G - Unexpected Plant Performance H - Other: a 7.( '4 CAUSE EVENT TYPE

2. P g

i W t 5p @-EquipmentFailure SIC - Significant Event EDI - Event of Interest Og x TBD - To Be Determined ]o pf 2 - Design or Installation Error 3 - Operating Error p 4 - Maintenance Error OTH - Other - M i 5 - External 30 6 - Other POTENTIAL AO: Criterion g ggy Prcposed Eye HODCE V. Engineer V Approved: /7 I 7k . r T *, I SecTion Leadar/' {

,. b ' i *
  • i A. Chaffee Branch Chief

) / -{ LLC $22 (p EVENTS ASSESSMENT PANEL First Screening: C osuraj sigaificance Descriptions Ch 47 7 REGION DRAFT INFORMATION NOTICE DISCUSSES SERIES OF DIFFICULTIES AT ST. LUCIE 2 WITH SQUARE D SERIES 8501 KPD-23 RELAYS INSTALLED IN RS11 SOCKETS. 3 THESE PROBLEMS IMPACTED DIESEL GENERATOR OPERABILITY DURING TESTING. i ~ s ' g,-~ [ LN/c/c 96a s a o opD 4 W ,,2 l (~- JJ ~ ETE-02 Page:1 03/08/96

e G:\\ FORMS \\ETS.RV1 ASSIEMENT SMET l I PANEL -- 1 YES _ NO i ASSIGle4ENT DATE: 1/19/96 ASSIGNED TO: V. HOOGE i PLANT & UNIT: ST. LUCIE UNIT 2 ~ i EVENT DATE: 11/6/95 i 50.72 REPORT NO: 1 MR NO: OTHER SOURCE REPORT: DRAFT IN FROM REGION II (1/11/96) RELATED REPORTS: SPECIALTY CODE: i EVENT /CONLITION Sb;i4ARY REGION DRAFT INFORMATION NOTICE DISCUSSES SERIES OF DIFFICULTIES AT ST. LUCIE l 2 WITH SQUARE D SERIES 8501 KPD-13 RELAYS INSTALLED IN RS11 SOCKETS. THESE PROBLENS INPACTED DIESEL GENERATOR OPERABILITY DURING TESTING. 4 SPECIFIC FOLLOW-UP ASSIGNNENT i DETERMINE DETAILS, EVALUATE SAFETY SIGNIFICANCE AND GENERIC INPLICATIONS. IN j ADDITION, ADDRESS THE FOLLOWING SPECIFIC CONCERNS: PREPARE PANEL PRESENTATION TO DETERMINE IF IN ISSUANCE IS WARRANTED. PREPARE TO BRIEF: _ YES _ NO TARGET CLOSE00T SCHEDULE: INITIAL SCREENING BY PANEL REGULATORY ASSESSMENT: EVENT / CONDITION SAFETY SIGNIFICANCE: _ OTH _ E01 _ SIG _ A0 i REMAINING OR ADDITIONAL FOLLOW-UP ITEMS: I CLOSEOUT TEXT REGULATORY ASSESSMENT: (Abstract of Closeout / Findings) Region II submitted a draft information notice describing diesel generator testing difficulties at St. Lucie 2 with electrical contacts of Square 0 Series 0501 KPD-13 relays installed in RSll sockets. The vendor

  • W Power Systems submitted a Part 21 report on a contact rating change and a contact i

failure at Point Beach for the same relay about six months earlier. The i contact failure was caused by licensee modification of the circuit to admit a i curs;nt 3 times the contact rating. The events assessment panel closed the i Part 21 report at that time because of minimal safety significance and lack of

A survey of event notifications the past two years and generic implications. of the list of generic issues revealed no other concerns similar to the St. A similar subject, stamping rather than achining or soldering Lucie event. socket contacts in digital instrumentation circuit boards, was treated in IN 94-04. Though the problem at St. Lucie needed to be corrected, issuance of the draft information notice is not warranted. i CLOSE00T/ FINDINGS: 11, 1996, Region II submitted a draft information notice to PCEB On January discussing a series of difficulties at St. Lucie 2 with Square D Series 0501 KPD-13 relays installed in RS11 sockets. These problems affected diesel generator operability during testing. The licensee conducted a contact resistance program,ver several years and concluded that two socket failures were related to support of the socket on the circuit board being based on soldered connections, an inadequate amount of solder on the failed terminals, and mechanical cycling of the solder joints because of relay removals and replacements. On April 24, 1995, MXW Power Systems submitted a Part 21 report to the NRC (designated as Pt21 95122) about a contact failure of a Square D class 0501, type KPD relay used in a diesel generator control panel at Point Beach. PECB learned from MKW that the burnt contact was apparently the result of a misapplication by the licensee for Point Beach because the licensee had modified a relay actuation circuit to include an indication resistance, increasing the current to about 3 times the contact rating. MKW decided to issue a Part 21 report to alert the NRC to a concomitant decrease in the The vendor stated that all of their nuclear Square D type KPD contact rating. customers except Point Beach and Turkey Point have over 10 years of operating .blem with the experience and Point Beach is the only plant to have a p: contacts. The generic implications of the Part 21 report are minimal. The difference between the original and actual make/ break current ratings of the Square D type KPD relays is small. It is not likely that this difference would significantly impact the circuits in which they are typically used. Years of problem free operating experience support this view. On July 26, 1995, the events assessment panel considered Pt21 95122 and closed it as an other event with no generic implications. A survey of events reported the last 2 years (search words included socket, solder) shows: Plant Date Event Braidwood 960130 Solder defects in edg Amerace relays w commercial add-on board to suppress coil deenergization Byron transient Pt Beach 2 950304 Blown fuse in 125 vdc ctri power because of shorted indicating light and socket l St Lucie 2 951120 Broken socket solder connections in 5 edg relays l Diablo 1 940426 Shorted phase potential light on startup feeder brkr Brunswick 1 940513 Riown fuse for cooling valve ctrl power when unlit

c

  • e i

bulb blew out ofsocket on removal of bulb cover Turkey Pt 4 940924 Unguarded bulb for shutdown rod off bottom light shorted when touched by operator, overloading i 120v internal power supply and tripping a fast-acting 10 amp brkr at the vital instrument power i i bus Mill 1 2 940624 Manufacturing defect (possible cold solder joints) in Bussman Type KTK,120 vac, 5 amp fuses installed in vital ac inverters 4 l The event at St. Lucie 2 in November 1995 is the only one related to the draft information notice, which describes circumstances at St. Lucie 2 in October and November 1995. Concerning electrical contacts in sockets, on January 14, 1994, NRC issued IN l 94-04: " Digital Integrated Circuit Sockets with Intermittent Conctact," to i all NRC licensees except licensed operators. This notice dealt with sockets manufactured by Augat, Inc., an international supplier of interconnections 4 systems for the computer, automotive, and telecommunications industries. The NRC learned about this recurrent problem during an analog-to-digital process I instrumentation inspection at Cook. The contact portion of these sockets were i produced by a stamping process rather than by a machining process. 1 j An electronic search of NUREG 0933'did not reveal any generic issues on this j subject. Based on this information, the draft IN from Region II describes a moderately safety-significant problem that is not generic. This draft information notice should not be authorized for issuance by the panel. 1 FINAL PANEL ASSESSNENT: The panel considered the significance of this to be insufficient to merit issuance of an information notice. It was judged not to be generic. EVENT / CONDITION SAFETY SIGNIFICANCE: x OTH _ E01 _ SIG _ A0 BASIS: _ RISK _ PROGRAMATIC _ MARGIN _ N/A GENERIC FOLLOW-UP ACTION REC 0 MENDED:. YES _ NO g PRIORITY (1,2,3,4)' _ IN _ BUL _ GL _ NUREG _ REG GUIDE FILE: G:\\vern\\ socket _it.ets BRIEF f

1. Priarity en h te M10 Riff la lamediate aselyment of resources (e.g.

for highly risk significant safety concerns) MICRITY 28 lieer tors actlen (e.g., alpificant safety 1soues not marrant r.g lamedlete actlan) i M10 Riff 3: Lens tors actlen (e.g., leeues of anderate to teu safety el etticence) MIGilfY 4: Resource dependent actlen (e.g., items that can be deferred) _,}}

Retrieved from "https://kanterella.com/w/index.php?title=ML20134B742&oldid=4233851"