ML20085M670
| ML20085M670 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry  |
| Issue date: | 11/23/1973 |
| From: | Eric Thomas TENNESSEE VALLEY AUTHORITY |
| To: | Oleary J US ATOMIC ENERGY COMMISSION (AEC) |
| Shared Package | |
| ML20085M669 | List: |
| References | |
| AO-BFAO-7339W, NUDOCS 8311090167 | |
| Download: ML20085M670 (3) | |
Text
.
~
TENNESSEE VALLEY AUTHO AITY T.--'3p
/
ei e
CHATTANOOGA, TENNESSEE i
^
3 3740'I U t /A
=. K =-0 November 23, 1973 SE'%'h'ESE0"5 PAMTNf' ASHIP iIt
[
%yk V. N. p-
.x i-(.
Mr. John F. O' Leary, Director Directorate of Licensing Office of Regulation U.S. Atomic Energy Commission Washington, DC 20545
Dear Mr. O' Leary:
TENNESSEE VALLEY AUTHORITY - BROWNS FERRY NUCLEAR PIAITI UNIT 1 -
DOCKET NO. 50-259 - FACILITY OPERATING LICENSE DPR ABNOR!GL OCCURRENCE REPORT BFAO-73394 The enclosed report is to provide details concerning reactor protection system condenser 1cw-vacuum switch m lfunction which occurred on Browns 4
Ferry Nuclear Plant unit 1 on November 15, 1973, and is submitted in-accordance with Appendix A to Regulatory Guide 1.16, Revision 1,.
October 1973.
I
- Very truly yours, TENNESSEE VALLEY AUTHORITY
]
/\\
.y)
.j
. ;/
y,
^,'.),,].7
./ mm fV' E. F. Thomas
. Director of Power Production Enclosure CC(Enclosure):
Mr. Normn C. Moseley, Director Region II Regulatory Operations Office, USAEC~
230 Peachtree Street, IM.
Atlanta, Georgia 30303
.,6.----4 e[(jj Q l
e yy!\\
=
4'o4 (gh
,y f 4 %.,,5 }pJ 4
fu /[ji'y -
l 8311090167 731128
.(s
- = a=ca a5aa !!=.
S r
j ams
n l
~
ABNORVAL OCCURRENCE REPORT Report No.--BFAO-7339W Report Date--November 23, 1973 Occurrence Date--Hovember 15, 1973 Facility--Browns Ferry Nuclear Plant unit 1 Identification of Occurrence Unit 1 reactor protection system condenser low-vacuum switch malfunction.
Conditions Prior to Occurrence Reactor at 25-percent thermal power during startup testing.
Description of Occurrence During accelerated surveillance testing on November 15, 1973, condenser low-vacuum pressure switch PS-2-1B was found to operate outside the technical specification setpoint of equal to or greater than 23 inches mercury vacuum as specified in Table 3.1.A.' The as-found setting was 22.8 inches.
Analysis of Occurrence The vacuun suitches are arranged in a one out of two taken twice 1cgic in.the reactor protection ::ystem. The other three channels were tested and found to operate satisfactorily; and, if required, the RPS would have performed its intendef.
function.
Corrective Action The switch was replaced with a new switch, calibrated, and functionally tested before returning to service. The accelerated testing frequency will be continued.
until three consecutive weekly tests prove satisfactory results. The testing frequency will then be reduced to biweekly and the original test schedule of once a month resumed after three consecutive biweekly tests prove saticfactory.
Failure Data Barksdale Model DIT-N1855 Serial No.: 'None.
9
'.i n
.L,
.'m-
m_._
o O
s..
FailureData(continued)
Switch Date Failure Corrective Action PS-2-IA 10/11/73 operated outside tech spec limits Reset switch PS-2-1B 10/11/73 Operated outside tech spec limits Reset switch PS-2-1A 10/25/73 Operated outside tech spec limits Reset switch l
PS-2-IB 10/25/73, Operated outside tech spec limits
. Reset switch PS-2-1B
. 11/15/73 Operated outside tech spec lb: tits Reset switch 1
9 i
4 a
)
e e e 4
1 n
gM e
n--,
~
y
,