05000249/LER-1980-008, Forwards LER 80-008/03L-0

Forwards LER 80-008/03L-0

ML17174A495
Person / Time
Site:	Dresden
Issue date:	03/25/1980
From:	Stephenson B COMMONWEALTH EDISON CO.
To:	James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML17174A496	List: 05000249/LER-1980-008, Forwards LER 80-008/03L-0 05000249/LER-1980-008-03, /03L-0:on 800307,during Refueling Outage While Performing Temp Switch Calibr Surveillance,Three Temp Switches Failed to Trip Per Specs.Caused by Drift,Excessive Gap Between Actuator & Switch Plunger or Dirty Contacts
References
80-242, NUDOCS 8004020363
Download: ML17174A495 (3)

LER-1980-008, Forwards LER 80-008/03L-0

Event date:
Report date:
2491980008R00 - NRC Website

text

---

___, __ e.

cdmmonwealedison

• B Dresden Nuclear Power Station A.fl. #1 Morris, Illinois 60450 Telephone 815/942-2920 BBS LTR #80-242.:

March 25, 1980 James G. Keppler, Regional Director Directorate of Regulatory Operations - Region III U.S. Nuclear Regulatory Connnission 799 Roosevelt Road Glen_ Ellyn, IL 60137 Reportable Occurrence Report #80-8/03L-O, Docket #050-249, is being submitted to your office in accordance with Dresden Nuclear *Power

• Station Technical Specification 6.6.B.2.(a), reactor protection system or engineered* safety feature instrument settings which are found to be less conservative than those established by the tech-.

nical specifications but which do not prevent the fulfillment of the functional requirements of affect:ed systems.

BBS:lcg Enclosure tep nson Station Superintendent Dresden Nuclear Power Station cc:

Director of Inspection & -Enforcement Director of Management Information & Program Control File/NRC

.. /

icav~z~3~s

~MR 3 1 1980

RC FORM 366: --*...... --*

U/S.NUCLEAR REGULATORY COMMISSION* *

>.77)..

~ "'

---~\\~

. eeNSEE EVENT REPORT

.*Lio:

-~

car-i:rROL BLOCK: r 1 1 1 10*

1

6.

(PLEASE PRINT OR TYPE ALL REQUIRED INFORMATION)*

O:IJ I I I LI DIR I s,. 3 IG)I 0 I ol'--1 0 I 0 lo* lo* I 0,_ lo ro IG')f 4 I ii 1 I 1 r l l©I* 1

• I© 8* 9 L.ICENSEE CODE

14.

15 L.ICENSE NUMBER 25 26*

L.ICENSE TYPE JO 57 CAT SB ffi. :~~~~~ W©I. o I 5 I o I o Io 1*2 I 4 I 9 101 o 13 Io I 1 I a.Io.l©I o I 3 J 2 I s I a 1* o IG) 8 60 61 DOCKET NUMBER 58..

69

. EVENT DATE 74 75 REPORT DATE 80

-=ev'ENT 0EscR1P~10N A~.D PROBABLE coNSEQUENces@.

f[ITI. I During Unit 3. refueling outage, while* performing temperature switch calibration I

~: I surveillance,. nrs* 2300""'. T,. three temperature* switches failed to. trip <l=, 200 degree F.

1.

as per tech... spec *. table 3*.2*.i.

Safetrimplications were minimal. since at least two I'

remaining switches in. channels B and" D were operable as. were: redundant channels A and I.

w* I C, and would have :auto isolated the HPCI system at 180 degree F.

Similar* events:

R.O

• f m I 50.,-237/74...;.63 and 50-249/80-11, I-3-73-4.and* I-3-74-6.

r lill 8-9 nu*

8 SYSTEM<<

CODE*

IS IF I@

9 10

~

- L.ER/RO CEVENT YEAR

~

REPORT I s1 01 NUMBER 21 22

CAUSE

CODE L!J@

11 l=J.

23 CAUSE' suscoDE COMPONENT CODE'.

l!J@ I I I NI s I T'I R: I u 1@

12 13 18 SEQUENTIAL.

OCCURRENCE REPORT NO.

CODE.

10 10 18 T 1/r Io 13 I 24

26.

27.

28.

29 80 COMP:

VAL.VE suBCODE.

SUBCODE

~@) Ul@

19 20 REPORT REVISION*

TYPE NO.

~ l=1 L~.l 30 31 32 PRIME COMP.

COMPONENT ACTION FUTURE TAKEN*

ACTION EFFECT SHUTDOWN

~

ATTACHMENT NPR~**

• ON Pl.ANT.

METHOD HOURS ~. SUBMITTED FORM SUB.

SUPPLIER MANUFACTURER L.:J@L.:.J@

L:J@ L.:J 1 o 1 o ! o I o I

• W@

• W@

33 34 35 36 37 40 41 42 L!!J@. IF Io is 111@

CAUSE DESCRIPTION AND CORRECTIVE ACTIONS @

43

44.

4T

IIIJ. 1 The cause of failures were drift, excessive gap between actuator and switch plunger,

rm* I or dirty contacts. ** The necessary adjustments were made to the switches, and they were

!IIJ. I recalibrated to 180 degrees F +/-5 degrees.

All HPCI area temperature switches shall I

ITIJ I continue to be tested during each refueling outage.

~.L-.~----~--~~~-------~--~--------~----------~--~---~--~--'

8 9

~

FACILITY IJQ\\

METHOD OF*

(.;'.'.;\\

STATUS

% POWER

. OTHER STATUS. \\:::;:J DISCOVERY DISCOVERY DESCRIPTION '23'

~

L.!:J@ I 0 I 0 I 0 l@I._ _____

N_/ A----~' ~@.._I _____ s_u_rv_e_i_l_la_n_c_e_T_e_s_t.;... ---*--------ii.

8

9.

10

12.

11 44 45 46 80 ACTIVITY CONTENT

'7"T:1REL.EASED O.F REL.EASE AMOUNT OF ACTIVITY 35

~* Ll.l@ L.Ll@I. N/A 1_:,

8 9

10 11 44 l.OCATION OF REL.E.ASE @

45 N/A 80 PEASONN EL EXPOSURES*

• r::;:;:.,

NUMBER

~TYPE.

DESCRIPTION

m.1 OI OIOl~~~-N/_A_-----------~--------------~

8 9

11 12*

13 80*

PERSONNEL. INJURIES

~

NUMBER DESCRIPT10N6

!TI]. I 01 01 Ol@)L------N~/A-------------------------------------~

8 9*

11.

12 80 LOSS OF OR DAMAGE TO FACI L.ITY f'43\\

71n'1 TYPE.

DESCRIPTION

\\;.::J

~

~@*

N/A 8

9 10 80 PUBLICITY G\\

NRC USE ONLY 1sr* '".".lt,;"'.;'\\ DESCRIPTION~

~~~'---------N_.IA

__ -----------~ II 11111111 Ill~

a

• ~

• 5s __ 6:...

so.a;

• 1*1

• 1'.

... l

---~~-*-*

---a_*_-*

ATTACHMENT. TO LICENSEE* EVENT REPORT* 80-008/03L-0 COMMONWEALTH EDISON COMPANY (CWE)

DRESDEN UNIT (ILDRS.,-3)

DOCKET' II 050;249 HPCL area. high* temperature: switch Ts*: 3-2J71B tripped repeatedly at: 204.3°F' iI1creasing..

The failure* can. be* attributed to instrument:

drift:.

. HPCI area. high* temperature switch TS3-2370D*tripped repeatedly at 273.6°F increasing.

The failure can.be. attributed to excessive gap between the actuata.r and switch plunger-. *The switch was found to _have a. gap of' approximately 0.120 in., as compared to a proper*

gap setting of. approximately. 060 in-.. The.gap was adjusted* to. 060 in.

HPCI area high temperature.switch TS 3~2370B.tripped repeatedly at 235°'7°F increasing*.

• The failure* was attributed. to loose mounting bolts on the. micro-:-swit_ch and dirty switch contacts.

Bolts* were tightened. and switch contact_s Clea1!_ed.

All switches were recalibrated to a setting of 180°F + 5° *in com-*

pliance with Tech. Spec. :'able 3. 2.1.. All. HPGT area temperature switches* shall continue* to be tested. during each refueling outage.