ML19257C541
| ML19257C541 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 01/22/1980 |
| From: | Fay C WISCONSIN ELECTRIC POWER CO. |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| References | |
| TASK-2.E.1.1, TASK-2.E.1.2, TASK-TM TAC-11692, TAC-11693, NUDOCS 8001290365 | |
| Download: ML19257C541 (9) | |
Text
.
O Wisconsin Electnc eowca coupas<
231 W. MICHIGAN, P.o. BOX 2046. MILWAUKEE, WI 53201 January 22, 1980 Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation U. S. NUCLEAR REGULATORY COMMISSION Washington, D. C.
20555
Dear Mr. Denton:
DOCKET NOS. 50-266 AND 50-301 SMALL-BREAK LOSS-OF-COOLANT ACCIDENT OPERATOR GUIDELINES POINT BEACH NUCLEAR PLANT, UNITS 1 AND 2 Mr. Denwood F. Ross' letter of December 6,1979 to Mr. Cordell Reed, Chairman of the Westinghouse Operating Plants Owners' Group, on the subject of evaluation of small-break Loss-of-Coolant Accident (LOCA) operator guidelines confirmed the approval of the Westinghouse guidelines with the revisions submitted to your staff on November 5,1979 for plants with nominal 1400 psi range safety injection pumps.
Mr. Ross' subsequent letter of December 27, 1979 discusses the modifications to the small-break LOCA operator guidelines which were submitted to your staff on December 21, 1979. We consider that these latest revisions are approved by your staff and have incorporated them into the Point Beach Nuclear Plant (PBNP) Emergency Operating Procedures for LOCA and spurious safety injection.
We also consider that these approved operator guidelines supersede the reactor coolant pump manual trip requirements established by IE Bulletin No.79-06C dated July 26, 1979.
The December 27, 1979 letter from Mr. Ross requires that utilities provide documentation showing the errors and their method of combination used in developing the reactor coolant system subcooling criterion for terminating safety injection. The subcooling criterion used in the PBNP Emergency Operating Procedures for LOCA and spurious safetf njection require that the reactor coolant system i
subcooling margin exceed 36 F prfor to terminating safety injection. The justification of this minimum 36 F margin is documented in the attachment.
The conservatively calculated instrument errors for PBNP result in a subcooling criterion which exceeds your staff's requirement that the criteriori should in U
no case be less than 30 F.
Mr. Ross' letter also requested utilities to document and justify any proposed revision to their procedures within 21 days if the calculated subcooling criterion does not permit timely termination of HPI for ron-LOCA events.
Currently, the non-LOCA generic guidelines for the Emergency Operating Instructions are being reviewed for the purposes of incorporating a subcooling criterion in the HPI N
termination criteria.
These activities associated with the generic guidelines will be completed and transmitted to the NRC by the Owners' Group Chainnan with-in the 21 day requirement.
. b.
1827194 com e
[
365 y
Mr. Harold R. Denton, Director January 22, 1980 The December 27, 1979 letter also requests the acknowledgement of a commitment to install instrumentation and readout devices, in the longer term, 0
that will ensure 20 F of actual subcooling margin based on the criterion used in our procedure.
It is our intention to install this instrumentation on both units of PBNP by January 1981, and to modify our procedures as necessary to 0
ensure 20 F of subcooling.
If equipment delivery delays or other problems beyond our control prevent the installation of such equipment by that time, then procedural changes will be made to ensure 20 F of actual subcooling based on the criterion in the LOCA and spurious safety injection procedures.
In addition, the plant process computer, which already has an alarm and readout of reactor coolant system subcooling, will be reprogrammed to ensure 20 F of actual subcooling.
0 Very truly yours, C. W. Fay, ir ctor Nuclear Power Department Attachment 182 195
m ww i. i JUSTIFICATI0fl 0F THE RCS SUBCOOLI lG SETPOI:lT USEJ Ifl THE PBl4P EMERGEriCY OPERATI:lG PROCEDURES P rocedures :
E0P-1A (4.11.3, 4.11); E0P-2A (4.ll.l.c, 4.11, 4.ll.2.c);
ECP-5B (4.3.3) e.g. E0P-1 A, Step 4.11
" Safety injection flow can be terminated if the following plant conditions are achieved.
4.11.3 The reactor coolant indicated subcooling is greater than 36 F... ".
iiote: Since the reactor coolant system (RCS) pressure must he above 2000 psig to secure safety injection, the operator can read the RCS narrow range (1700 - 2500 psig) pressure instrument and either the average RCS tem-are running,VG) or cold leg temperature (T ), if reactor coolant pumps perature (TA C
or core exit thermocouple readings to determine the magnitude of RCS subcooling. The plant process computer also has an alarm and read-out for RCS subcooling.
I.
Errors in Indicated Pressure dormal Transmitter Reference Accuracy
= +.5; of scan (includes hysteresis, linearity, and
__.005 of 300 psi
= e Reactor Protection Analysis, Tel Con, lu17/79
~ 4 psi repeatability) (Dick Miller, Westingnouse
-r and Foxboro Technical Manual, 611GM Transmitter) 1.lli of full scale Accuracy of Dead Weight Pressure Tester and
=
.0011 of 2500 psi Current Tester Used in Calibration
= +
7_ 3 psi (PBi4P IJC Engineer, Tel Con,12/5/79 &
=
WEPCO liPO IaC Engineer, Pers Con,12/5/79)
+.5% of span Allowed Calioration Tolerance
=
[.005of800 psi (PUilP I;C Engineer, Tel Con, 12/19/79)
=
- 4 psi
=
+.56 of span Artient Temperature Effects on Transmitter
=
+.005 of 800 psi (dick Miller, Westinghouse Reactor Protection
=
+ 4 psi Analysis, Tel Con, 12/17/79)
=
+ 1.0% of span Maximum Transmitter Drift
=
[.01of800 psi (Dick Itiller, Westinghouse Reactor Protection
=
+ 8 pis Analysis, Tel Con, 12/17/79)
=
+.5% of span
'lormal Instrument Accuracy
=
~
.005 of 800 psi (Dick !1 iller, Westinghouse Reactor Protection
=
Analysis, Tel Con, 12/17/79 & Foxboro
~+ 4 psi
=
Technical Manual, Model #66SC)
- .55 of span Actient Temperature Effects on Instrumant
=
+.005 cf 300 osi (Jics Miller, Westinghouse Reactor Protection
=
+ 4 psi Analysis, Tel Con, 12/17/79)
=
+ 1.0% of span Maximum Instrument Dri ft
=
7.01 of 800 osi (Dick fiiller, Westingnouse Reactor Protection
=
i Analysis, Tel Con, 12/17/79)
, _ 8 psi
=
182g196 fiormal Indicator Accuracy
= + l.0% of span (Foxboro Technical Manual for
= +.01 of 800 psi flodel #65PX indicator)
= [ 8 psi flaximum Indicator Reading Error
= + 1/4 of smallest meter division (Bob Monka,PBriP P,eactor
, +.25 of 2u psi Operator, Tel Con, 12/11/79)
+ 5 psi Maximum !loreal Instrument Error
5(4)-+(3)-+3(8)-+(5)-
= + 18 esi Note : Since the above normal errors are random and independent, they can be combined statistically by taking the square root of the suu) of the squares.
Maximum Post-Accident Envi ronment
= - 3.6 % of test pressure Error for Transmitter
=
.036 of 2030 psi (Environment of s285 F and 60 psig steam)
= - 74 psi (WCAP 7410-L. Topical Report, Environmental Testina of Engineered Safety Features Related Eau 1orent, Dec.,1970, P. A-8 for Unit 4 (foxboro Model 4611GM))
Note: Althougn the errors were negative throughout the test, a positive error cr' +51 of test pressure will be assumed for conservatism in cases where a positive error is worse.
Maximum Asst. red Post-Accident
= +5% of maximum pressure Environment Error ror Transmitter
= +.05 of 2500 psia
= +125 psi Note: Errors due to the radiation exposure of the transmitter are negligible for the radiation expected.
Maximum Total Pressure Instrument
= normal error + environment Error in an Adverse Er.vironnent error
= 18 psi + 125 psi
= 143 psi II. Errors in Indicated Temoerature A.
T-llarrow-Rance Ins trument Process Measurement Error
= + 3". o f s pan (Dick Miller, Westingnouse Reactor
= [.03 of (590 F - 515 F)
Protection Analysis, Tel Con, 12/17/79
= 1 2.3 F RTD Refemnce Calibration Curve Accuracy
=12F (Dick Miller, Wettingnouse Reactor Protection Analysis, Tel Con, 12/17/79) 1827197 Accuracy of Current Tester
.015 of span
=+
Used in Calibration
= 7.0001 of 75*F (WEPC0 tiP0 I&C Engineer, Pers Con,12/5/79)
=[.01F Allowed Calibration Tolerance
= _ +_.51 of span (PBliP ISC Engineer, Tel Con, 12/19/79)
.005 of 75 F
=+
= + 0.4 F Calibration Error Due to fion-Linearity
= +.5% of span f 75 F
- j @g licroal Instrurent Accuracy
= + 0.5% of span (Dick f1 iller, Westinghouse Reactor
= 7.005 of 75 F Protection Analysis, Tel Con, 12/17/79)
=[0.4F Ambient Terrperature Effects on Instrument
= + 0.5% of span (Dick Miller, Westinghouse Reactor
= 7.005 of 75 F Protection Analysis, Tel Con, 12/17/79)
=[0.4F f4ximun Instrument Dri ft
= + 1.0% of span (Dick Miller, Westingnouse Reactor
= [.01 of 75 F Protection Analysis, Tel Con,12/17/79)
= 1 0.8 F Strip-Chart Recorder Error
= + 2.0% of full scale (PBNP I&C Engineer, Tel Con,12/10/79)
= 7.02 of 75 F
=[1.5'F Operator Readout Error on Recorder
= + 1/4 of smallest recorder division (Bob Monka,PBNP, Reactor
= + 1/4 of 1.0 F Operator, Tel Cori, 12/11/79)
=[0.3F Maximum fiormal Temperature (TAVG) E rror = i[( 2. 3)-+(. 2)"+ (.01 )-+4(0.4)-+(0.8)-+
(1.5)-+(0.3)-
= + 3.0 F flote : Since the above errors are random a.1d independent, tr.ay can be combined statistically by taking the square root of the sum of the squares.
The Maximum Difference Between
= 1/2 (core ai at Rated Core Exit Temperature and Tgyg Power) (Fraction of Full When Evaluating Criteria for Securing Power Decay Heat at Two SI with RCP's Running (TH-TAVG)
Minutes After Snutdown)
(PBNP FFDSAR, Table 4.1-2 and PBNP Tec.inical
= 1/2 (610.1 F - 552.5*F)(1.02)
Speci fications, P 15.3.3-8) i 1.03 F Maximum Post-Accident Envi rontrental 2 error equivalent to four Error junction boxes (Sears, John A., Foxboro Test Recort
,= 1 02", o f 75 F No.1013, June,1973, p. 3)
= +.02 F 182)198 (in an adverse environnent) AVG) Error tiaximum Total Temperature (T
= Maximum normal error +
maximum envi ronmental error + maximum (T -Tgyg) o
_= 3.0 F +.02 F + 1.03 F
= 4.1 F 3.
Tnermocoucles at Core Exit Thermocouple Reference Accuracy
=+3F (Dick Miller, Westingnouse Reactor
=
Protection Analysis, Tel Con, 12/19/79)
_.75% of reading Calibration Accuracy
=+
(PB iP ILC Engineer, Tel Con,12/5/ 79)
= +.0075 of 600 F
= + 4.5 F Analog-to-Digital-to Engineering Units
= + 1% of reading Instrument Accuracy (fl. Pitterle, PBflP Reactor = +.01 of 600 F Engineering Group, Tel Con, 12/12/79)
=6F Maximum Instrument Dri ft
= + 1% of reading (Dick Miller, Westincnouse Reactor
= +.01 o f 600 F Protection Analysis,'9/12/79)
-[6F Maximum flormal Thermocouple Error
= 43)-+(4.5)-+2(6)-
= + 10.l*F IJote : Since the above errc.s are random and independent, they can be combined statistically by taking the square root of the som of the squares.
~'
Maximum Post-Accident Environment Errcr
= error equivalent to two (Sears, Jonn A., Foxboro Test Reoort junction boxes
.Olt of 600 F No. 1013, J une,1973, p. 3)
-=+
=[.1F Maximum Total Thermocouple
= normal - environment errors Temperature Error
= + 10.l'F +.1 F (in an adverse environment)
= + 10.2 F C.
T Wide-Rance Instrument g
Process Measuren.at Error
= 13% of span (Dick Miller, Westinghouse Reactor
= ;.03 of 600 F Protection AN1ysis, Tel Con, 12/17/79)
= + 18 F RTD Reference Calibration Curve Accuracy
=12F (Dick Miller, Westingnouse Reactor Protection Analysis, Tel Con, 12/17/79) 182'/ 199 4
Accuracy of Current Tester
.01% of span
=+
=7 I [.0001 of 600 F Used in Calibration (UEPC0 NPO I&C Engineer, Pers Con,12/5/79)
.1 F Allowed Calibration Tolerance
=+.5% of span (PBNP ISC Engineer, Tel Con, 12/19/79)
= [.005 of 600 F
=+3F Calibration Error Due to Non-Linearity
= +. 5 ', o f s p a n
= +.005 of 600 F
=[3F Normal Instrum nt Accuracy
= + 0.5% of span (uick Miller, riestinghouse Reactor
= +.005 of 600 F Protection Analysis, Tel Con, 12/17/79)
=[3F Antient Tenperature Effects on Instrument
= + 0.5% of span (Dick Miller, Westingnouse Reactor
= 7.005 of 600 F Protection Analysis, Tel Con, 12/17/79)
= [ 3'F Maximum Instrument Drift
= + 1.0% of scan (Dick Miller, Westinghouse Reactcr
= 7.01 of 600 F Protection Analysis, Tel Con 12/1;f '3)
=[6F Strip-Chart Recorder Error
= + 2.0% of span (PBNP I&C Engineer, Tel Con,12/10/L)
= 7.02 of 600 F
= [ 12 F Operator Readout Error on Recorder
= + 1/4 of smallest recorder division (Bob Monka, PBNP Reactor
= + 1/4 of 10 F Operator, Tel Con, 12/11/79)
=[2.5F Maximum Jormal Ten perature (T ) E rror = - [( 18r +(.2)-+(.1)-+4( 3)'+(6)'+(12)'+(2.5)']
C
.= + 23.4*F (strip-chart recorder)
Note: Since the above errors are random and independent, they can be comoined statistically by taking the square root of the sum of the squares.
~.
Maximum Post-Accident Environment
= error equivalent to two Error junction boxes (Sears, John A., Foxboro Test Reoort 2 [.0l*; of 600 F
=+
- 10. 1013, June,197 3, p. 3)
.1 F Maximum Di fference Between
= (Core c.T at Rated Power)
Core Exit Temperature and TC (Fraction of Full Power Decay When Evaluating Criteria for Securing Heat at Two Minutes After SI with RCP's running (Ty - T)
Shutdown) c (PBNP FFDSAR, Table 0.1-2 and
= (610.1 F - 552.5'F) (1.02)
PBNP Tecnnical Speci fications, p. 15.3.3-8)
X 0.035 4 2.1 F 182/)200 Maximum Total Terperature (T ) Error
= Maximum flormal Error +
C Maximum Environmental Error
+ Maximum (Tn-T )
C
= 23.4 F +.1 F + 2.1 F
= 25.6 F III.
Calculation of Minimum Required Subcooling Margin with Consideration of Instrument Errors A.
Under Adverse Environmental Conditions Inside Containment Minimum Absolute Pressure at
= Indicated Absolute Pressure -
an Indicated Pressure of 2000 psig Maximum Pressure Instrument Error
= 2015 psia - 143 psi
= 1872 psia Maximum Indicated Temperature
=TSAT (1872 psia) - Maximum To Ensure Subcooling at an Indicated Temperature Measurement Error Pressure of 2000 psig
= 626.5*F -
4.1 F (T yg)
A 10.2 F (Thermocouple) 5.6 F (T )
C 622.4 F (TAVG)
=
616.3 F (Thermocouple) 600.9 F (T )
C Minimum Required Subcooling (ASME Steam
=TSAT (indicated pressure) -
Tables,1967)
Maximum Indicated Temperature To Ensure Subcooling
= 636.9 F -
622.4 F (T VG)
A 616.3 F (Thermocouple) 600.9 F (TC) 14.5 F (TAVG)
=
20.6 F (inermocouple) 36.0 F (T )
C B.
Under Normal Environmental Condicions Inside Containrrent Minimum Absolute Pressure at
= Indicated Absolute Pressure -
an Indicated Pressure of 2000 psig Maximum Normal Pressure Instrument Error
= 2015 psia - 18 psi
= 1997 psia Maximum Indicated Temperature
=TSAT (1997 psia) - (Maximum to Ensure Subcooling at an Indicated Normal Temperature Measurement Pressure of 2000 psig Error + Maximum (Tg-T )
C (ASME Steam Tables,1967)
= 635.6 F - (3.0 F + 1.1 F)(TAVG) 10.1 F (Thermocouple)
(23.4 F + 2.1 F) (T )
C
= 631.5 F (TAVG) 625.5 F (Thermocouple) 610.2 F (T )
C 182// 201 liinimum Required Subcooling
=TSA7 (indicated pressure) -
( ASTE Steam Tables,1967)
Maximum Indicated Temperature To Ensure Subcooling
=TSAT (2015 psia) -
631.5 F (TAVG) 625.5 F (Thermocouple) 610.2 F (T )
C
= 636.9 F -
631.5 F (TAVG) 625.5 F (Thermocouple) 610.2 F (T )
C
= 5.4 F (TAVG) 11.4 F (Thermocouple) 26.8 F (T )
C tiote : The RCS subcooling margin of 36 F used in the PBriP Emergency Operating Procedures is greater than or equal to the minimum required values calculated above.
1827 202
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