05000335/LER-2077-004, Digital Data Processing System Calorimetric
| ML18144A723 | |
| Person / Time | |
|---|---|
| Site: | Saint Lucie  |
| Issue date: | 02/18/1977 |
| From: | Schmidt A Florida Power & Light Co |
| To: | Moseley N NRC/IE, NRC/RGN-II |
| References | |
| PRN-LI-77-37 LER 1977-004-00 | |
| Download: ML18144A723 (3) | |
| Event date: | |
|---|---|
| Report date: | |
| 3352077004R00 - NRC Website | |
text
Cl i. BOX 013100, MIAMI, FL 3310'I
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- - GEEST FLORIDA POWER 5 LIGHTCOMPANY February 18, 1977 PRN-LI-77-37 Mr. Norman C. Moseley, Director, Region II Office of Inspection and Enforcement U.
S. Nuclear Regulatory Commission 230 Pcachtxcc Street, N. W., Suite 1217 Atlanta, Georgia 30303
Dear Mr. Moseley:
REPORTABLE OCCURRENCE 335-77-4 ST.
LUCIE UNIT 1 DATE OF OCCURRENCE:
JANUARY 20, 1977 DDPS CALORIMETRIC The attached Lj.censee Event, Report. is being submitted in accordance with Technical Specification 6.9 to provide 30-day notification of the subject occurrence.
Very truly yours, A. D. Schmidt Vice President Power Resources MAS/cpc Attachment cc:
Robert Lowenstein, Esquire Director, Office of Inspection and Enforcement (30)
- Director, Office of Management Information and Program Control (3)
PEOPLE..
~ SERVING PEOPLE
CONTROL BLOCK:
I IN:ENBEE EVENT REPORT (PLEASE PRIBT ALLREQUIRED II4IFORIVIATION)
L!CEN SEE N4ME toog F
L S
L S
1 0
7 89 14 15 REPORT AEPOAT CATEGORY TYPE SOURCE
~01 00N"r~
~L
~L 7
8 57'6 5S 60 LIENEE TYPE 0
4 1
1 1
25 '6 COClilET NUMBER 0
5 0 0 3
3 5
EVENT'4TE 0
1 2
0 7l 61 66 69
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'CENSE NUMBER 0-oloooo 0 EVENT TYPE
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30.
31 32 I
AEPQAT 04TE 7
0 2
1 8
7 7
74 75 80 EVENT OESCRIPTION Qa2 While reviewincr ower ascension test data from before and after the 7
8 9 60 QOg 5-month fuel reconstitution shutdown See LER 335-76-35 dated 7 23 76 a
7 89
~
80
~04 possible error in indicated ower from the Di ital Da'ta Processin S stem 7
89 80
~05 DDPS calorimetric rimar heat balance) ro ram was noted.
An inten-89:
80 MGLS 'ive investi ation confirmed that the calorimetric ro ram was in error 7
89 C'SI ICE CQQE COOS
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7 8 S 10 11 12 CAUSE OESCRIPTION ol~
There are two COMPCiNFNT COOE N
S T
R U
PRME COMPCNcNT SUPPUER N
80 C MPQNENT MANUF4CTUPER VCL4TCN F
112 0
N 44 47 48 methods in the calorimetric ro ram for convertin analo 7
8 9 60 g
f dwater flow si nals to di ital en ineerin units.
One method involves l
7 8 9 60
~1 0 a direct 4 to 20 ma linearization while the other method allows for a OTHErl STATUS NA PROBjQLF-CONSEQUENCES t11l 7
89 FAC:Lfii'T4TUS
.C POWER
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7 8
9 10 12 13 FORM OF ACTMTY CQAl cNT AELBLSEO OF AEL~MSE AMCUNT QF 4C44VITY
@~2 Z
~Z NA 7
9 9
10 11 PERSONNEL EXPOSURES NUMBER TYPE CESCAIPTlQN Pg~oo o
z 7
9 9 11 12 13 PERSONNP IiVJURIES NUMBER CESCAl~QN
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7 89 11 12 METHOC OF CLSCQVEAY 44 45 46 NA NA NA ClSCCVEAY CESCAlPTZN NA LOCATlQN CF A'cC4SE NA 80 80 60 99 LOSS OR OAMAGE TO FACILITY TYPE OESCAIPTICN z
7 89 10 PUSLICITY NA I
60
~1IS 7
89
~19 7
89 ACOITIONAL.=ACTORS P
o for continuation of Event Descri tion and Cause Descri tion.
60 7
89 M. A. Scho man 60 cpo 04t4 og'p
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'g'ICENSEE EVENT REPORT REPORTABLE OCCURRENCE 335-77-4 PAGE TWO r
EVENT DESCRIPTION (Continued) and indicated 2.57% below actual power (at nominal 80%).
The program was corrected and now functions properly.
This is the first occurrence involving software problems with the DDPS.
(335-77-4).
'AUSE DESCRIPTION (Continued) special linearization curve for each flow transmitter.
The second method will allow for non-linear behavior of different transmitters.
During initial power ascension, the direct 4 to 20 ma linearization method was used.
Following fuel reconstitution, the program and data base were reloaded into the DDPS and the second method of converting analog signals to engineering units was used.
. However, the program contained an erroneous scaling factor for the.'range of the flow transmitted.
This error caused the'indicated feedwater flow'and reactor power to be lower than actual.
The program has been corrected and all calorimetric inputs reviewed to verify that no further errors. are present in the special linearization method.