ML20065K557
Text
.
-m 3
UNITED STATES 8
NUCLEAR REGULATORY COMMISSION o
I
{
.E WASHWGTON, D. C. 20555 AE0D/E210 k..... +o FEB 2 31982 MEMORANDUM FOR: Ronald C. Haynes, Regional Administrator Region I FROM:
Carlyle Michelson, Director Office for Analysis and Evaluation of Operational Data
SUBJECT:
INADEQUATE SWITCHGEAR COOLING AT BEAVER VALLEY, UNIT 1 Two events occurred at Beaver Valley during the past sunner of potential safety significance regarding adverse environmental effects on safety-related equipment.
The enclosed LERs (81-59/02L and 81-71/03L) report that the Number 2 battery charger output breaker tripped on thennal over-load during surveillance testing. The switchgear rooms are provided with I
the same flow-through ventilation system circulating outside air. The chargers are located in the switchgear rooms and contribute to increasing the room temperature when operating.
Similar breakers in the rooms have not tripped.
Portable fans have been used to increase the airflow around the battery cbrger.
The potential for tripping the output breaker would increase if more than one battery charger is operating during elevated ambient temperatures be cause of increased heat load. For a loss-of-offsite power event, the heat contribution of the operating battery charger could potentially affect other safety-related swi,tchgear equipment.
The ventilation system is not safety related and would not be available during this event.
Corrective actions taken by the licensees include rebalancing the venti-lation flow in the switchgear rooms and revising the surveillance proce-dure for testing the battery chargers, to prevent more than one charger operating at the same time.
In addition, a station modification request has been made to increase the' ventilation flow in the switchgear rooms.
The licensee has tested the breakers under full load (without high ambient temperatures) and believes that there is no problem with the breakers.
Our evaluation of the events indicated that the licensee had not expanded his investigation to verify the environmental qualifica. tion of the breaker.
Since the breaker was not found defective, the qualification of the breaker for mild environments should be evaluated by the licensee to ascertain the root cause for the failures.
gO 32 820628 UDELL82-261 PDR
'l Ronald C. Haynes We recommend that the licensee complete the appropriate analyses and modifications to prevent recurrence of this type of failure before the summer of 1982.
The current refueling outage may be an apprcpriate time for modifications.
The resident inspector is following the licensee's investigations into the problem.
The implications of this event suggest that the loss of the ventilation system could have potential safety significance requiring additional generic review by the NRC.
Operational occurrences at other plants have already attuned +.his office to possible inadequate ventilation design and performance situati.as which could result in subjecting electrical equipment to adverse mild environmental conditions. As a result of IE Bulletin 79-01,79-01B and others related to environmental qualification of electrical equipment, it is our understanding that the staff is reviewing in detail the adequacy of equipment to withstand accident environments.
We were not able to confirm that the same level of review will be performe6 for non-accident conditions exemplified by the Beaver Valley events and events involving inadvertent actuation of the fire protection system addressed in another AE00 memorandum.
~
In responding to the Bulletin, it may no! be apparent to the licensees to address qualification of electrical equipment which are required to operate, but not exposed to postulated accident conditions. These occurrences may be useful in evaluating the scope of the licensee's response to the bulletins.
This effort has been coordinated with the Environmental Qualificatlon Branch, Division of Engineering, NRR. The AEOD contact is Wayne Lanning.
~
Carlyle Michelson, Director Office for Analysis and Evaluation of Operational Data EnclosJres:
As stated cc w/ enclosures:
HDenton, NRR DBeckman, RI, Beaver Valley ZRosztoczy, NRR RDeYoung. IE VStello, CRGR 4
e y-c-(---,e
-,,.r.-
.-c---
j
-. 3. -
t.['
co~rnet stoC.e 1 1
I I
i i
ig i,ts,se,niNr oa ry,c Att arouinso 6,oanitioN g j ? { A l B lV l S l 1 l@l 0 l0 l-1010101010 l-1010 [@ll. l1 11 l1 l1 l@l l
l@
I
+8 36 8C1*.L4 7 "i J
3 7 s'T 13 8 9 LICENSEE CCDE M
4 Li:t.5E NV:="2 48 oIiI
",*[c~' l L }@l 0151010101313 l!. @l 0 l 61 1151 81 11@l 01 71 y
- oN'T sa en svaNTeave
- 4 s
aa.:nt :4:s to 5
so,
si coc g; w y,i, -
EVENT DESCRIPTION AND PRoBABtE CoNSECUENCES h
- o 121 I on 6/15/81 at d730 hours with reactor onw r at 45'z. the batterv chsreer suoniv to 125 VDC bus Nc. 1-2 was lost when the So. 2 battery charger output breaker trippe
- o,3, i The. charger was declared inoperable while power operation continued withir i o g., ; ;
open.
the limitations of Technical Specification 3.S.2.3.
The health and safety of the lo e 3j [
l o 151 l public was not jeopardized as the No. 2 battery remained operational.
lo l?l 1 l o la i 1
?
se c0VP.
vatvg SYSTEM cAust CAL 1E coot coes suecoce cov cNENTcoct sus::cs sus::cs l E l c l@ Lx_j@ ! z l@ Iz Iz I z I z I z 1218 W@ W @
~
loisi 18' la 10 7
s 9
.0 11 12 12 OC0t'ARENCI at:0mT R EV'SION
$1CUENTI At '
gg g.po EVENrvtAm mt'omr NO.
COCE Tvet No.
I i
@,as g i sl 11
[ --]
101519 l W
10 i s i I tl I-I LO_J -
2 22 23
- 4
- 6 27 03
- 9 3J W2N 'isTYEd o'lltEr s;p,gy,w
,,,u,, g 4,7,agpgp,cll,g, n,7,t y,p y,y,vlf,4t.,'
s L
[
[XJ@[_F_j@
I z l@
W@
l 010 l 010 !
[Y_j @
lNl@
lzl@
l zl 919
- s 24 2n
- s 2
o u
as u
CAUSE oESCRIPTioN AND CORRECTIVE ACTIONS h l 1oll Excessive heat in the, emergency switchgcar area caused the breaker to trio on
)
1-eil l thermal overload. A portable fan was placed in the vicinity of the batterv chat Futur to cool the breaker. ' At 1120 hours0.013 days <br />0.311 hours <br />0.00185 weeks <br />4.2616e-4 months <br /> the charger was returned to se.rvice.
s,,7, I actions will be to investigate improvements to the ventilation system on the g i ; 31 l li ia l I battery charcert 7
3 9 1
Discovgny :ES:mi,*:0A STA "57CwtR oTHER17ATUS 5
Y IiisiLE_J@.]Ol9lSl@l N/A l
lAl@l Control Room Alarm LecArion Cr =stsast @
' !:mTv cd'veyr Aucunt o, acimrv @ l N/A l
N/A p'
\\-
=t'. 4sas :p estras li is I Lij @ I zi@l f
jg/ ( g 44 e5 8
d 9
'O st g Y,, f4 /-
- tploNNtt Ex,CSURE3
/;
\\
f \\,p/
}T o Nu'.tB E R TV'E ats EISTICN P
li i:1 101010 !@l z l@l N/A a
y y v t.r ;r
""',*T *"E'i:.i,,,cN @
[\\ f, M./. h V}3 v" / p - '
i, o
% d k% # d I hl10l0f01@l N/A gfc#1V V /r )
f 6 \\"
!,:s.s o, om :".,2:i,oNe.2cr..v. @
V,Mg e 4 9
~
- ne..1 d
le t il I z l@l N/A
-8107240335 B10713 % e^I"bb 4 /
V
=*
2:
- E. fr \\"C tJSE C' A
- * 'C
- PDR ADCCK 05000334\\
[. g. g
g.j'."*"'"' ' @
S S
PDR sd i;i:;iii gf3 u o
.+
P 2-G;-E5:5 g
S. ' ace?
-:. s.
.!2..g:p,mtetzg=
=
?
[1,, m [ AL T
1 N'
W. D. L'A".19$LV1J LJLK$ULW2Y COMMISSIDN a
LICENSEE EVENT REPORT
-~140L SLOCK. l l
l 1
I I
(PLEASE KINT 0 : TYPE ALL REcutRED INFC*w.AT1:N)
I t r I s Iv is il Igl o lo I-I o 10 lo lo lo I-lo lo @l4 li-l1 Il li lG l
Ig a
sggssgg ccgg te 18 u'.ENSE NwueER 2h 26 uCENSE TYPE Ji1 si GT S4 O IL @lo l 5 lo I o 10131314 @l ois lo 151811 l@lo 19 I o l
- s i 11@,
60 el CoCKET NWMSER 68 59 EVENT oATE 84 il REPORT E
40 s.rs- :Es:mirTios A.No PResArits CoNSECUCNCES h n 8/5/81 at 0231 hours0.00267 days <br />0.0642 hours <br />3.819444e-4 weeks <br />8.78955e-5 months <br /> with tne reactor at 99'; power the battery :5.arger l
supply to 125 VDC bus No.'1-2 was lost when No. 2 battery chstger eutput i
breaker tripped open.
The charger was declared inoperable while
- ver j
~
operatica continued within the limitations of Technical Specificarions l
e 3.8.2.3.
The health and saferv of the oublic was ne: ieocardized as the I
f ba t te rv rer.ained. ooera tional. Thi's is the second reoorted event.
I I
r so-a SYS*Eu CAvst CAUsE CoWP.
VALVE C:ct CooE susCcCE CeuPonENTCooE suscoot suecoCE I ri cl@ [Jj@ l 21@ I z ! z i z i z l z i z i@ W@ Lz._I S 9
10 11 12 13 14 13 20 SEoVENTIAL oCCUpptNCE REPORT
' REilSloN EVENT VEAR REPORT No.
CooE TYPE No.
@ g* ERreo 18 l 11
[.--J l01711l M
.! o l 31 W
1.-:
lo I g
,_21 22 23 24
- S 27 28 29 30 31 22
^WSa* Tis' PK"M.. '"#/,5?ll*-
.o!OPfC# rem loIoIo@IoI
. S!E2R 5"af C#5r
- EIBM" NovRs s
LYJ@
1 xl@
II l@
~l2 iS I919 I@
ix1(31rl@
LzJ@
lzl@
=
ss as se as aC - se -
<1 as u
a, m =s ossen Pr:ON AND CORRECTIVE ACTIONS h.
- T Excessive heat in the charger enclosure area caused the breaker :: trip 1
'r en a thermal overload. A oortable fan was used to remove the' hea snd at 1
J !
0333 hours0.00385 days <br />0.0925 hours <br />5.505952e-4 weeks <br />1.267065e-4 months <br /> the charger was back in service. The station engineerir.c group 1
I has becun an investiention looking towards imoroving the cresent area I
I
,r or batterv charter ventilation system.
ao o
- % PohvER oTHER STATUS i
y otscovtRY oESCRIPTION 5":a Control Reor. Alarm l
r I3 In I o l 9 l@l N/A l
Wh.s
~
i2 ii 4
as s0 g
4, AwouNTof ACTiviTv @ I toCAvioN of RELEASE @
=r ww-ca =ELEAst N/A I
N/A I
! F_s) L.z.J@l D
to t
e4 45 se
- T*:5:a.%EL Epcstats
% m's k-
"*Pg Q($;Mi'T1oM
- I o I o l@U!;j@l N/A I
- Tu'S h sELeNJLa.gg es. awe t e
- ts:RiPTioN
- IoIol@l N/A l
80 D
11 17
---+ lps ce Sava?! *3 84C:UTV E T 0 0'5 f n o m-a 10904 PDR ' A6yCK 05000334 l
-~=t
- Es:aiat'cN
- G"l N/A S
-__-TSE:...tios@
~
- a l N/A
}
!I' I l!!Il!!It Y
ss
.r n.;
C fl2-6-:-iS 5 o
'*. S. 1.s c e v.
.g