ML20247G333

Forwards Summary of NRC Understanding of How Restrictions on Low Power Physics Testing Will Be Met.Approach Satisfactory

ML20247G333
Person / Time
Site:	Seabrook
Issue date:	05/21/1989
From:	Nerses V Office of Nuclear Reactor Regulation
To:	Ellen Brown PUBLIC SERVICE CO. OF NEW HAMPSHIRE
Shared Package
ML20245K651	List: ML20245K649 ML20247G333 ML20247R202 ML20247R210 ML20247R227 ML20247R245
References
FOIA-89-309 CLI-88-10, NUDOCS 8905300378
Download: ML20247G333 (16)

Text

>> MS g i5 g NUCLEAR REGULATORY COMMISSION-g WASHINGTON. D. C. 20555 May 21, 1989 Docket No. 50-443 Mr. Edward ' A. Brown President 8' Chief Executive Officer New Hampshire Yankee Division Public Service Company of New Hampshire Post Office Box 300 Seabrook, New Hampshire 03874

SUBJECT:

SEABROOK LOW POWER PHYSICS TESTS U

I In accordance with the Commission Order, CLI-88-10 dated December 21, 1989, for any low power testing license that may be issued for Seabrook Unit 1, the license will be conditioned to allow operation at pcwer levels not in excess of five percent and shall permit no more than 0.75 effective full power hours (EFPH) of operation.

In consideration that such a license may be issued, we have reviewed the manner in which your staff intends to perform low power physics tests and remain

} within the license restriction of 0.75 EFPH and 5% maximum power' level. The enclosure presents a summary of our understanding of how the two restrictions are expected to be met. We find the approach to be- satisfactory.

p Sincerely, s_- ., . 8 M c. G Victor Nerses, Project Manager Project Directorate I-3 Division of Reactor Projects I/II L

Enclosure:

i As stated cc w/o enclosure:

See next page f

Public Service Company of New Hampshire q Cc:.

l Thomas Dignan, Esq. E. Tupper Kinder, Esq.

'o John A. Ritscher, Esq. G. Dana Bisbee, Esq.

Ropes and Gray Assistant Attorney General-

'225 Franklin Street Office of Attorney General Boston, Massachusetts 02110 208 State House Annex Concord,-New Hampshire 03301 Mr. Bruce B. Beckley, Project Manager Public. Service' Company of New Hampshire Resident Inspector Post Office' Box 330 US Nuclear Regulatory'Comission Manchester, New Hampshire 03105 Post Office Box 1149 Seabrook, New Hampshire 03874 Dr. Mauray Tye, President Sun Valley Association Mr. A. M. Ebner, Project Manager-

'209 Summer Street United Engineers & Constructors Haverhill, Massachusetts 01830 Post Off ke Box 8223 Philadetph?a, Pennsylvania 19101 Robert Backus, Esq.

Backus, Meyer and Solomon Steven Oleskey, Esq.

116 Lowell Street Office of the Attorney General Manchester, New Hampshire 03106 One Ashburton Place P.O. Box 330 Diane Curran, Esq. Boston, Massachusetts 02108 Harmon and Weiss

, 2001 S Street, NW Carol S. Sneider, Esq.

Suite 430. Office of the Assistant Attorney General Washington, D.C. 20009 One Ashburton Place P.O. Box 330 Philip Ahren, Esq. Boston, Massachusetts 02108-Assistant Attorney General State House, Station #6 D.- Pierre G. Cameron, Jr., Esq.

Augusta, Maine 04333 General Counsel Public Service Company of New Hampshire Mr. Edward A. Brown, President Manchester, New Hampshire 03105 and Chief Executive Officer New Hamp hire Yankee Division Mr. Jac s 1 Pesc!ki Public Service Company of Public Service Company of New Hamsphire New Hampshire P.O. Box 300 Post' Office Box 300 Seabrook, New Hampshire 03874 Seabrook, New Hampshire 03874 Seacoast Anti-Pollution League Regional Administrator, Region I 5 Market Street U.S. Nuclear. Regulatory Comission Portsmouth, New Hampshire 03801 475 Allendale Road 25 Maplewood Ave.

King of Prussia, Pennsylvania 19406 Ms. Diana P. Randall Ashod N. Amirian, Esq.

70 Collins Street Town Counsel for Merrimac Seabrook, New Hampshire 03874 376 Main Street Mr. T. Feigenbaum Public Service Company of New Hamsphire Post Office Box 330 Seabrook, New Hampshire 03874

m. ,

l Edward A. Brown, Public Seabrook Nuclear Power Station Service Company of New Hampshire CC*

Mr. Calvin A. Canney, City Manager Mr. Alfred Y. Sargent, City Hall Chairman 126 Daniel Street Board of Selectmen Portsmouth,.New Hampshire 03801 Town of Salisbury, MA 01950 Board of Selectmen Senator Gordon J. Humphrey RFD Dalten Road ATTN: Tom Burack Brentwood, New Hampshire 03833 531 Hart Senate Office Building U.S. Senate Ms. Suzanne Breiseth, Washington, D.C. 20510 Board of Selectmen Town of Hampton Falls Drinkwater Road Mr. Owen B. Durgin, Chairman Hampton Falls, New Hampshire 03844 Durham Board of Selectmen Town of Durham Mr. Guy Chichester, Chairman Durham, New Hampshire 03824 Rye Nuclear Intervention Committee Jane Spector c/o Rye Town Hall Federal Energy Regulatory 10 Central Road Commission Rye, New Hampshire 03870 825 North Capital Street, N.E.

Room 8105 Chairman, Board of Selectmen Washington D. C. 20426 RFD 2 South Hampton, New Hampshire 03827 Mr. R. Sweeney R. Scott Hill - Whilton Three Metro Center Lagoulis, Clark, Hill-Whilton suite 610

& McGuire Bethesda, Maryland 20814 l 79 State Street Newburyport, Ma. 01950 Mr. Richard Strome, Dire.ctor '

1 . iL Cashman, Chairman New Hanipshire. Office ci t merge 6cy Board of Selectmen Management Town of Amesbury State Office Park South Town Hall 107 Pleasant Street Amesbury, Massachusetts 01913 Concord, New Hampshire 03301 Adjudicatory file (2)

Honorable Peter J. Matthews Atomic Safety ae.d Licensing Board Mayor, City of Newburyport Panel Docket City Hall U.S. Nuclear Regulatory Commission Newburyport, Massachusetts 01950 Washington, D.C. 20555 Mr. Donald E. Chick, Town Manager Congressman Nicholas Mavroules Town of Exeter 70 Washington Street 10 Front Street Salem, Massachusetts 01970 Exeter, New Hampshire 03823 Mr. G. Thomas Mr. John C. Duffett Public Service Company of President and Chief Executive Officer New Hampshire Public Service Company of New Hampshire Post Office Box 330 1000 Elm St., P.O. Box 330 Seabrook, New Hampshire 03874 Manchester, New Hampshire 03105

a

?

t .

l Enclosure I H'

Seabrook 55/0.75 EFPH Operation GENERAL INFORMATION 3 0.75 effective full power hours (EFPH) operation for Seabrook is equiva-lent to 0.75 x 3411MW x 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> = 2558 MW -br. At5% power (or170.6MW)' t t t Seabrook could operate continuously for 15 hours1.736111e-4 days <br />0.00417 hours <br />2.480159e-5 weeks <br />5.7075e-6 months <br />. The tests to be conducted are primarily_ low power physics tests and a natural circulation test. The majority of the low power physics tests are conducted in the zero power test range (approximately .01% power). Low power flux mapping will be conducted at approximately 1% power and the natural circulation test'will be conducted at approximately 3% power.

The process that will be used to determine core exposure during the low power test program will be identical to that used to determine core exposure during normal plant operation. However, instead of using a secondary calorimetric to calibrate (normalize) the power range nuclear instruments the core AT power will be used to calibrate'(normalize) theintermediaterange(IR)nuclearinstruments. This calibration will-be based on the full power core temperature risc (core A T). One of the first evolutions to be performed in the low power test program till be to increase reactor power to 3% (based on core AT) and record the IR detector currents. From the data obtained by this evolution, the normal-irction enrs.txt , frr each intermediate range detector (amps /% power) n will be determined.

A process computer program has been written to record the IR detector currents and the time between program executions. The program then utilizes this data along with the IR detector normalization constants to

. calculate core exposure. The EFPH will be the sum of the test power levels times the test time and this sum will be maintained below 2558 Mw -hr.

t

4 2-SPECIFIC INFORMATION Reactor power will be measured using the core temperature rise normalized to the full power core temperature rise (comonly referred to as AT power). The IR detector outputs will then be normalized to the measured core 4 T power. It will be necessary to calibrate (normalize) the IR detectors to trace core exposure because most of the low power testing is conducted in the zero power test range where core AT is O'T but the IR detectors are producing a current equivalent to approximately .01% power.

The uncertainties associated with the measurement of core 4T are about the same magnitude as the measurement itself. To offset this, a full power core 6T of 57.0'F.is used to determine the IR detector normalization constants. A full power core AT of 57.0*F is conservative with respect to the expected full power value of 59.4*F. The process of normalizing l

L the IR detector output to match coreoT power also normalizes out any uncertainties associated with the IR detector outputs. Thus, the IR detector outputs simply inherit the error associated with the core oT measurements which has already been accounted for.

All instruments necessary to monitor core exposure are calibrated with the exception of the IR detector output normalization. IR detector normalization will be performed during normai plant startup regardless of any core exposere .mitations.

There is no specific plan or schedule for expending the .75 EFPH. The only plan that exists is the low power test sequence which, if goes as planned and without any unforeseen test or equipment difficulties, should be completed within the allotted exposure limit. The tests are expected to be completed in about ten days.

A special computer program has been written for the main plant computer to calculate and track core exposure. An administrative procedure will be written to ensure that the exposure limit will not be exceeded and to document core exposure'. The administrative procedure that tracks and documents core exposure will contain a section on manual tracking of core exposure if the plant computer is unavailable.

- - - - . - ~ ,_

< i i i REACTOR ENGINEERING DEPARTHENT CALCULATION COVER SH I l

l

. i RECALC - S p - g pq i CALCULATION TITLE: ~ SHEET ~ l'~ OF 6

[ M k&IG W Vf'(^5/cG4 bf 574 d5 h 1

& hh DJw 9twev i'es t @rsegmm 1

~l 1

.. j l

- l l,

l i

l 1

PREPARED BY: fhk, DATE /f 89 i REVIEWED BY 4 [a cm -s DATE_d !/ / ,

. . . APPROVED BY: M-k, _ ~ _ _ _ _ DATE I k g-l 1

RD 0719 Rev. 00 l

WECAt-c'. coo 4 5 M 2,e i .

/. s rJ+t<

. rz Ostec.tv Cn, vevs>~ ces+cas Sv cove npa.c m Trnckiay Dua9 7% l.sw Pswer Test- (Przyrc.m.

2. o ?c< < Pera Il-e (parfase of ~tk i s c<a.C c salc tI M is 71) clefe<m, et e.

1%, %L d e fechv- c.nt ve.. s i+ ce<rmts

$b p~a.U vi e e ess eq e Cive (.A0 ogfos u >< clav,< y ttu gn%

4es+ pv ye.~ .

1o 12der we< -

/. hen asce Obscv. ,+cc Ptkecfrn u+k Ptv yve m usea -h> Ce&culc.h tdeet  % aw<

clun% %  % ?uwev P blyc u u N sfi +tg ncn C A# e c ho./ ces 4/ cps t)

A.o A sm,pti m s h&ML- -

S.Lo _Sfun m a,v_vF L H1 .

77e a m<a co3A6 & bA nt Po(ech Ch <m ds is

/6 60 5 FP,M /ca~y - n< t.e nk-6

____________.___.___...___________m

.Q' ,

.__ ,-  :- - ~

g~ .

4 y3, m

L .

66 9cxty ch GdculcdaM G.( G+s vsc 4T fsw iect;cdica s fro %. c- AU

.6T it GI *t- 10 w

9 -M/ powu. 47 oF q c.swesa sipw = m avedes sre n x# s'/N g, ,

h .te... & s f at w fo n ds ,463t2. , Ac3t7, A0122, emJ ho3z? md 0.2 in umh * % pmm TP. Ghfectev Gets EwweeteerdV 9w Cowedu dr 9 w Ley 1 s gro -' . I3 , t 2.

9Nd . 7/ .41 iXto'* .W . BST Wz 6 .v/ ~'

9Ato *'

~

.3i

,8o

.E6 22.

/ x/0 " /. c. 7 . 9/

krug 3 6xto~' s.40 1.75

.9 4 fo~' z.o f I80 i Mo *T 2. t l

• l. 7_8 (org A co A to -(- .

2L .&+

'3 Af6

l. I 6 . l.03

,. I Ato# 1. 6 l 22 -

4.2 kiemaue +ls. slope. (ie 6

% obswwd T R- 9 de & cu w s+d5 cQ Ovvt eleg cmes /M G%w .

)

/3T Pn i r1clicdOk S. D ;> is &m cdicu is qwsedect yqWivedly cu fl y .i..

Slege. c <J cu. Maw s u.mes.e pcvi n ( ttz lik ev k cf .,-run 1' ce n cb> cm c, c<<<k

/fr y//C ceA c.d.&w,

\ l#rp L ses /% W S.S3 r/s

l  % 7.- G. 43 .uo~'

l-o 0y 3 S. 4 > /to - '

Lovg + G.5e ,yc - '

9 ec ac -e v-coos 5%

A / f k ey 1 k n c, y ;f- de of +be. topp tJavi e4  % sicpe c)f +k s r pw venus or em re chfeo c w e~;t O.MpiAL /Me~ be w.w.

W Uc< v o J idu s iH -t24 1M af % Coup LT gn.s cm be. ca tM Es%e/n  % 40 ih v c a < u % .s Gieam ym e+ dev- loc els 6.3 GeAseman cdim 6f- c< up s tsp e cuot co ou.7 o p ; A te J fo too g pw.

Asv y Sbye- 5.95 4 ~ A,p- /% pw du ve-T &v <v-te2 - v /co'2 gw

= G. 9e5~ 4/rG w p 7 4:< x /Co % ~= S.9 6~x/C* % .

k4e-; helimiMcay vai ue. c l' 3 2- c<< u u.x p m . dz /

in tsr ?M wc< s 1 N r f c, ~ ps, '?w cliscuv,jm uviit t k,g w o.ne.l m c Wt~e.

c)um aau.e is ce,aste+~r in.n ofk W tynd 6 +-

6/ mite de s < '<g n .

Tk a ki+-e vat a will be ve e n lac,.le d ch i n .g- qw c< s c c a d c u .

C. 4 DefewM.ah e oF EFPM T nc.bhty froepm Ccrt 44/ow crus 74-d3, 7LL initid (/c.(u cf- /4,00 0 wos c4e. lev Ah e /

O.s hilcos (CC T

/Q-4 a q.1 m {l00 7.X i E FFM t m.h .)

l jg, g o g Me 0

Gsq-r-a

_ _ _ _ _ . _ . . _ _ .. _ _ _ - - - - - - . _ - - - - - - _ . - . - _ - _ - _ - . _ - _ _ . _ - _ _ _ - _ _ . --_._ . _ . - _ _ _ _ _ . . - _ . - _-__-..-_-_._._.__n

y- ~r.- ~~ "" - -

~

g{ g g gp ,,, ( Tc l(s,k 'f-fa % ll Q owW Seettm S. 3  % tuw Cuvvts't~

cn vers,is, clofem eaeJ tn cs 1 k ts cuz.4 C<.s Nvllet/IS 160 'A i EP Ph ___ .

jg gg EFPM S. 9 TA/u " A wy , (10b %j l n o H ) ~

cwf ~m&

(c . S~ Be<se / cm

')%

a M e,w c~ a v s + s. 9s </u-r < ~is

+ 6 lier A t > > fr< n JM :s CAL c. d cJen +o c<ic4

1. se: ny In flc 0P4&o'obt 5 oft <v:t.ty W PW Sero @w- 96ver Tc=st %p lw I xtc~' a4, = . 0017 ?l pw h Te r- A g N.- Iwa-> g. ,ot3s w g.w B& %r _

Zit. Qwtw- CwkJ-

/7; G.?v.or' ag, I a7:

f /./9.nu-' anp 3% .

/. 2 8 %fo *

• a y s f '<f 2. 3 9 4 to ~' y, ST 2. D @ -* cry  ;

w___________.______.-_---------. - - - - - - - - - - --

,.-...v , P,..Ccru,1RE d _ ,,

rec 6LC cco4 , , , , . . , ,

3r .

2, 'l, 3

} I i l l6 I__ i  ! i

. ! , i a . . . . i i _f' . 1 1 6 e i 6 ,

t i i .,

i -. i . , . .. i

+.+1 .

r-t..t... r- - - - i i , . . .

--- ! , i

'.ii , ,.

i  ;'.

, i i

l

_ a.

F

+ r, t -, , ,

., .  ; . .., . . r, -

, , . i. , ~

, i , , . . .... . . .-

=.

i i i

. .s . >- . +.

un _ > H- -.,gr r. tm1,,

1, . , - , . i, .

c m, .,

y. r. , .~i i,, , i , . , ,

+. 3a+u i_ _ _ _ . _

, ,  : ; i ; ,

4 >

l  :

1 i

,..J g.;'

.i

' 63 I

-J

. 6 , f, . ,ii

-t I ,. . .

i y f , . i ..I

,. , i , ~~, .

3 _

y" . . .i , ~ ~

a .

rt .  % i r i

.X 4 ,g-

... sw gu . y

-, < - +~

--l /-

., i, j w.

. - -.. rm-

-;_< ._ , , t. +

, , , , , , y . -f . ,. .. ~. g, ,

..,..J!. I ' ' I ' I *

. s .

c .

1 '. l *}

j i .. i*-

. ._ I 'I i ,J, ,J .; ..

g  ;

.e 4.. , ,

3 I .I I. f '>

~

u

% f . . . -

4. ,, a I 'I' ' ' ' '

3 "*g

. . I fi i . . . j -- ' * --*,

• i .

-*--,1 ..'*

- -*- T - *-

i , j ,

9.

. g ,..

m. . . .. . - . -

4r f f l' i L

' ' 4 f.

f...... ' .f y I i *

..I.I-f I f I ,,_L.,

' . .' ' . II i f , _ . _

1

. . .,. ;, ,i

.. i. . . '

.t.. * , 9 5

.*I i

'. b e

e r A f A . .

1.4-(, - . ,>

,, v, , ,_ . ,

, .;- ,u . _.

~ i

! -l i- -

f u

,r o . ~ ._.

g s. m u ,

dy ,

ll.- - . - - I-

= . . J, , . _ . . - , ,

mqf , ,

i q ,t ...9 ,

r _. . . _j +_ __

4.....  ;

v1, g fj #

r-

,7 ,

J y.

y s i

>.. . . _ _ g

.s .. y .y ,': ;;

1 v .

g9% _ .-

, o, -

- v,l - - . . .- .

or '

1 ,>

U 1,

o

-l ...g . lyl \l ....N 's .' - n f

y ,

l .. , ......_ + g . .

a y

w

, u.,

i m Rr q,f - ..,

y g , yjp . . . . . .

m,

& Ql _, ,. . . Q . . . . , . , , , ..

o.,

,' N l } f w o, .

-... . . . i .. ..

Ea I  : Ej _ * '

,_,,I I I 6

~

I * '

n,Q .I \11 ..

. i .4 ._

1 --

g  : p._-  ; . a .. __ . .

l t_f .. . f l

I----

l i_,,,L ' ' ' ' ' '

,,. ( I I I" i , .

s  !# f ., .

• I. 41 ,,;. _ ' ' I g_ ., _ .' . .. i. t i1 t !,

i i l

I I ,; J _L  ; i . i

• l' I ' g.' l l .

.}... ..

. s .. . !..i f .} . .

f l . . f. 4 ,

~

j . . i"~ i . . . i r i

i f

_; _,",1....,

t .

I i .

' -~

.i

. j- ,4

-+- - - - - 91" 11' i ,

r --- &., . .

. 6 i .

. .i 1

. 6 r i .J . i . .-

- i 6 f. .. f. f .-..a{ j; , .} , ;..

, ,l ,, ..,

, 3 ;

1_

I f i . iJ 1 .

3,,4 F 1 I . i

, 4 ,,;', 4 5 ,

--f-1 i

. j .L . ..y}

. g. .

gs ,I

,.'1-

,I u -

l q i

' . ;,;' ; ],

a ..

, l I. . .T'~ .

i g,_2 , . .. i 6 Il  !

I *, i e . i . 6 .

11 , i I . . 2

~t *g

T P ~~**j f'/p " 4 H

. '2 J. ! ,

M .

l i

1i*3.

.I

• 'i. .*

.. Ai i 1.

1, I

i i . ~~ I i I

i

. i !

6 i .

- v

'.i 3.i 0

. i O t.o 2o A T PMu5 P._ L.coLEsc7&rn

_ .. . -_ -_ - _ - - _ . - - . _ - - _ - . ~ --

.l. .

- FZg442d 2. j g -~

^

EECM C ocoq.

l l.

Functional Description for the Program Used to Calculate Accumulated Core Exposure During t.ow Power Physics Testing e

9 9

c; .*p _

Submitted by: Q .,V .h( M f_L ,4 39_i36ff('[

Approved by: __

[fc f/ hw l f j f gj o

0

.__m__________.___._____m._ . . . _ _ . _ . - _ _ _ _ _ _ _ . _ _ _ - . _ . _ _ _ _ _ . . _ . . _

__ _ - _ _ ~ _ . -

-- ~~ m~

!.0 INTRODUCTION When the low power license for Seabrock is issued, it is expected to contain an accumulated core exposure limitation of 45 effective full power minutes (EFPM). To verify compliance with any EFPM limitations

.and to simplify will be used. the core exposure tracking, an NPCS computer program This functional description specifies the requirements and basis for the calculations that will be ured by the program to track accumulated core exposure.

2.0 DEFINITION OF TERMS EFPM, Effective Full Power Minute LPPT. Low Power Physics Testing MCB. Main Control Board HPCS, Main Plant Computer System RE. Reactor Engineering 3.0 ASSUMPTIONS 3.1 The power Invel existing at the time of program execution has existed since the last program execution.

3.2 The response of intermediate range instrumentation versus power level is linear.

4.0 DESCRIPTION

A program for tracking core curnup currently exists on the MPCS; however, it lacks the capability to accurately track core exposure at low power levels.

during icwA power separate program is required to track core exposure (in EFPM) physics testing. The new program will operate as follows:

4.1 The program will be ectivated by the periodic scheduler on a 5 minute basis. Since the program is temporary in nature, it will M a ',tand alone program and will not be incorporated in thu existirig

+ -

RE 5 minute task (RE5 MIN}.

4.2 Due to the temporary need for the program, no DA1 disc storage will be used. All tracking will be dene with 6 calculated points which are described below!

- Calculated Point 1: This point is the cumulative amp-minutes calculated using intermediate range chanse) 35 indication. This C point will be updatcc every program execution.

- Calculated Point 2: This point is the camulative amp-minutes calculated using intertrediate range channel 36 indication. This C point will be updated every program execution.

l

,,,, l

, _h 30f- C

- Calculated Point 3: This point is the channel conversion con-stant used to convert intermediate range channel 35 amp-minutes

-into an ETPM value. Thts C point will be updated by RE. as required, using the Analog Management-Function at the HCB. This point will not be RELIAB cnecked since use of a subftttute value causes an unreliable flag to be set.

- Calculated Point 4: This point is the channel conversion Con- i stant used to convert intermediate range channel 36 amp-minutes into an EFPM value.- This C point will be updated by RE. as required using the Analog Management Function at the MCB. This point will not be RELIAS checked since use-of a substitute value causes an' unreliable flag to be set.

- Calculated Point 5: This point is the current core exposure as of the last program execution. This C peint will be updated every program execution.

- Calculated Point 6: This point is the sean nutr.ber corresponding to the previous progran execution. This C point will be updated every program execution.  ;

4.3 Every time the' program is executed, it will perform the following items:

4.3.1 Obtain the analog values for intermediate range channels 35 and 36, and convert to units of aftps. If one.value is

• unreliable, the alternate value will be substituted for the unreliable value. If both values are unreliable, a value of zero amps wl!1 be assigned to beth channels.

4.3.2 The difference in scan number since last program execution will be calculated and converted te minutes.

4.3.3 The Step 4.3.1 values will be multiplied by the Step 4.3.2-delta time to obtain the change in amp-minutes for each intermediate range channel.

4.3.4 The change in amp-minutes from Step 4.3.3 will be adced to the applicable calculatec points te obtain new values of cumulative arrp-minutes.fer each intermediate range ctannel.

j Calculated points, 1 and 2 will be updatec with the new values.

4.3.5 The cumulative trrp-minutes from Step 4.3.a will be multiplied by the applicable channel conversion constant (calculated points 3 and 4 input into the program anc not RELIAB checked) to obtain an EFPM value for each intermediate range channel.

4.3.6 The current core burnup in EFPM will be obtained by averaging the two EFPM values of Step 4.3.5. The result will be usec to update calculated point 5.

4.3.7 Calculated point 6 will te udpated with the s'can number of the current program execution.

• * ~

, W o( \

o

' ^

5.0 DETAILS OF CALCULATIONS S.1 Conversion of MPCS intermediate range analog values to amps.

The analog units of MCAMPS. values for intermediate range.c.hannels 35 and 36 are in To obta must be multiplied by 10 jn the required urlits of amps, the MCAMPS 5.2 Calculating to minutes. the time since last program execution and converting Delta Current Scan number Time (Minutes)

= [ ( scan ) - ( of previous ) ) x ( (5 secondy) x g 1 minute number. program execution scan 60 seconds) )

Note that if.the delta scan time is less than zero (indicating a new day has started), a value of 17,280 will be addeo to the current scan titre in order to obtain the delta scan time.

5.3 Converting amp-minutes to EFPM using channel conversion constants.

The value of cumulative emp-minutes for intermediate range channel 35 and 36 is converted to ETPM using channel conversion constants. The initial value of the channel conversion constant is determined as ex-plained below; however, the values should De updated when a more accurate value has been cbtained from LPPT data. -

Revision 2. of the Precat,tions. Limitations and Setpoints for Nuclear Steam Supply Systems states that the initial setting for intermediate range channels is such that the full power current for 100% is 10-4 amps.

is: Therefore the initial value for the channel conversion constants 100% 1 EFFH

[ 10-4 amps 3 3 = 10

1. 4 EFPM/ amp-minute (100%) (2 min)

During LPPT overlap data consisting of intermediate range currents and core delta temperatures (in units of % power) will become availatle.

This data should be eval.lsted for possible Channe' conversion constart update as described below:

5.3.1 Verify the data represents stable conditions (constant power level and constant RCS temperatures).

5.3.2 Average the % power values to obtain a core average % power.

1 1

hp To f ' l V .-

S.3.3 f Correct the-core average % power by multiplying by (51'F/57'F) where: j

' ~

l

1) 51'F.is'the conservative value initially used by delta I

temperature instrumentation to convert delta temperature  !

to % power.

\

2) 57'F'is an estimate of actual full power delta temperature.

.(Note that an alternate value specified by the RE Department Supervisor can also be used).

5.3.4 Calculate new channel conversion constants as follows:

Calculated Point 3 "E % power (from Step 5.3.3) 3

• E 1 EFPM

~3

!R 35 indication (amps) (100%) (1 min)

Calculated 1 EFPM Point 4 "E % power (from Step 5.3.3) 3

• E 3 IR 36 indication (amps) (100%) (1 min) 5.3.5 If directed by the RE Department Supervisor, update calculated points 3 and 4 with the Step 5.3.4 values using the Analog Management Function at the NCB.

S.4 Calculation of current core exposure. -

Calculated point 5 for current core exposure in EFPM will be the aver-age of the EFPM calculated by both intermediate range channels as shewn below:

Calculated 5

C Calculated C C

=.C alculated3 Point 1 E Point 3 3 + b alculated Point 2 3 b alculate:-

Poirt 4'__

2

- _ _ . _ - - - _ - - _ . _ - _ _ - _ - _ _ _ - - _ _ _ _ - _ _ _ _ _ - _ _ _