Text

Response to Request for Additional Information - Developmental Revision I Technical Specification Section 3.8 - Diesel Generator Batteries
	ML15280A509
Person / Time
Site:	Watts Bar
Issue date:	10/07/2015
From:	James Shea; Tennessee Valley Authority
To:	; Document Control Desk, Office of Nuclear Reactor Regulation
References
	CNL-15-220
	Download: ML15280A509 (12)
	v • d • e

Tennessee Valley Authority, 1101 Market Street, Chattanooga, Tennessee 37402 CNL-15-220 October7, 2015 10 CFR 50.36 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001 Watts Bar Nuclear Plant, Unit 2 Construction Permit No. CPPR-92 NRC Docket No. 50-391

Subject:

Watts Bar Nuclear Plant Unit 2, Response to Request for Additional Information - Developmental Revision I Technical Specification Section 3.8 -

Diesel Generator Batteries

References:

1. Electronic Mail from J. Poole (NRC) to G. Arent (TVA), Batteries, dated October 5, 2015

2. TVA Letter to NRC, Watts Bar Nuclear Plant Unit 2 - Submittal of Developmental Revision I of the Unit 2 Technical Specification & Technical Specification Bases and Developmental Revision D of the Unit 2 Technical Requirements Manual and Technical Requirements Manual Bases, dated June 16, 2014 [ML14169A525]

The purpose of this letter is to respond to a request for additional information (RAI) provided in Reference 1. Tennessee Valley Authority (TVA) was requested to confirm that the Diesel Generator batteries are designed to operate at 50o Fahrenheit (F). This question was identified by the Nuclear Regulatory Commission during their review of Technical Specification (TS) 3.8 provided in Development Revision I of the Watts Bar Nuclear Plant Unit 2 TSs (Reference 2).

The enclosure provides TVAs response to the Reference 1 RAI regarding batteries.

There are no new regulatory commitments associated with this letter. Please direct any questions concerning this matter to Gordon Arent at (423) 365-2004.

U.S. Nuclear Regulatory Commission CNL-15-220 Page 2 October 7, 2015 I declare under penalty of perjury that the foregoing is true and correct. Executed on the 7th day of October 2015.

Respectfully, Digitally signed by J. W. Shea J. W. Shea DN: cn=J. W. Shea, o=Tennessee Valley Authority, ou=Nuclear Licensing, email=jwshea@tva.gov, c=US Date: 2015.10.07 19:14:15 -04'00' J. W. Shea Vice President, Nuclear Licensing

Enclosure:

Response to NRC Request For Additional Information - Diesel Generator Battery Temperature cc (Enclosure):

U.S. Nuclear Regulatory Commission, Region II NRC Senior Resident Inspector - Watts Bar Nuclear Plant, Unit 2 NRC Project Manager - Watts Bar Nuclear Plant, Unit 2

Enclosure Response to NRC Request For Additional Information - Diesel Generator Battery Temperature

Background

By letter dated June 16, 2014, Tennessee Valley Authority (TVA) submitted the Watts Bar Nuclear Plant (WBN) Unit 2 Developmental Revision I of the Technical Specifications (TS) and TS Bases, and Developmental Revision D of the WBN Unit 2 Technical Requirements Manual (TRM) and TRM Bases to the Nuclear Regulatory Commission (NRC) (Reference 1). By electronic mail (email) dated October 5, 2015, the NRC provided a request for additional information (RAI) regarding TS Section 3.8 of Developmental Revision I (Reference 2).

The following response to the Reference 2 RAI addresses the NRC staff concerns related to the design of the Diesel Generator (DG) batteries.

NRC RAI TS 3.8.6.3 establishes battery operability based on battery cell parameters and average electrolyte temperatures for vital and DG batteries. If the average electrolyte temperature of the representative cells is outside the lower limit (< 60oF for vital batteries and < 50oF for DG batteries), the battery is considered inoperable. The staff requested information about Station battery sizing and testing criteria for 60oF ambient temperature and DG battery at 50oF ambient temperature.

The applicant provided details on correction factors for station batteries for temperature range at and above 60oF and correction factors for DG batteries for temperature range at and above 60oF and NOT 50oF. The staff recommends that the applicant confirm that the DG batteries are designed for operating at 50oF.

TVA Response Based on TVAs review of 125VDC Diesel Generator Battery sizing analysis calculation WBNEEBMSTI110062; the design temperature used for sizing the DG batteries is 50oF. provides pages from the calculation confirming the use of 50oF The cell sizing factor for 50oF corresponds to 1.19 and is obtained from Table 1 of IEEE Standard 485, IEEE Recommended Practice for Sizing Lead-Acid Batteries for Stationary Applications (Attachment 2). Therefore, TVA confirms that the DG batteries are designed for operating at 50oF.

References

1. TVA Letter to NRC, Watts Bar Nuclear Plant Unit 2 - Submittal of Developmental Revision I of the Unit 2 Technical Specification & Technical Specification Bases and Developmental Revision D of the Unit 2 Technical Requirements Manual and Technical Requirements Manual Bases, dated June 16, 2014 [ML14169A525].

2. Email from J Poole (NRC) to G. Arent (TVA), Batteries, dated October 5, 2015.

CNL-15-220 E-1

ATTACHMENT 1 TVA Calculation WBNEEBMSTI110062, 125VDC Diesel Generator (DG) Control Power System Evaluation Extracted Pages

NPG CALCULATION COVERSHEET I CTS UPDATE Page 1 REY 0 EDMS/RIMS NO. CTSJYPE; EDMS TYPE:

90021480004/826 900202 406 calculation CALCULATIONS (NUCLEAR) cak: Trtle:

125VDC DIESEL GENERATOR (DG) CONTROL POWER SYSTEM EVALUATION BBANQH NVMBER CYB REV NEW REV CALCID NUC WBN EEB WBNEEBMSmt0062 028 CTS UPDATE ONLY 0 NO CTS CHANGES

- ~ ~__..-'.v 10(

(Verifier and Approval Signatures Not Required) (For calc revision, has been and no CTS changes required)

Y.!::i1I (check one) SVSTEMS UNIDS o181. 1 O. 2 0. 3 D I

082 NIA APPLICABLE DESIGN pOCUMEN!(§)

I I pCN.E[)C NIA CLASS!RCADON See Bev Log NIA E OUAUJY SAEED' RELATEP7 UNVEBIREP SPECIAL REQUIREMENTS 1 oeslGN OIJJPUT SAR/TS and/or !SfSI

.ei:1...t.TED? (If yes, QB = yes) a"'" JMPTION &NrvnA uumNG

I ..TT: ** " ,

~ -* - .. -*

Yes 181 Non I I

£ , K Yes 181 No L I Yes D No 181 Yes D

No 181 Yes D No~ Yes D No 181 CALCULATION NUMBER BEOl.JESTOR PBEPABING QISC!PUNE VERIFICATION METHOD

1NEW METHOD OE AN6LYS!S Name: vupetel PHONE: 301*228-7658 EEB Design Review 0 Yes 181 No PREPARER v.r:NAMEAN~Sl~./7 DATE CHECKER (PRl~NAMEA~SIGN) . DATE VlnuPatel ~cc.>CY to/>/,?_ DSBhatla (\,(~~ 1o/2Ji,_

VERIFIER (PRINT NAME ~G~ h . - DATE APPROVAL (PRINT NAME AND SIGN) DATE FAJl.~oQ SoF1 { fl- d'- - 10/tofrv ~Cox ~~ ~

10

//1fi2 I

STATEMENT OE PRQBL.EMIABSTRACT STATEMENT of PROBLEM:

Verify the adequacy of the design and compliance with design criteria and SAR requirements. Review and document and Impact.

ABSTRACT:

This calculation evaluate the adequacy of the 125 VDC DG Control Power System battery sizing, charger sizing, protective devlc1 sizing, short circuit and cpordlnation, Appendix R, fleg. Gulde 1.75 - Associated Circuits, cascade fuses and maximum voltag.e to the control circuit components. Equipment submerged due to MELB event Is identified

and the impact of Its submergence on the 125 VDC DG Control Power System Is evaluated in Appendix I. See Section 8.0 and 9.0 for results and conclusions.

The following revisions are Revision Log Change Only: 17, 21 The revision log changes must be worked in conjunction with the full version that issued the entire calculation.

See revision log for total pages and FSAR and Tech Spec compliance U:GmIUTY EVALUATED AND ACCE~ FOR ISSUE A-tl. /~ /1 InltJaJs: Oate ; __ /d(r:1.e.//2 MICROACHE/EACHE . Yes r l No D ACHE NUMBER(S)

TVA40532 Page 1 of2 NEDP*2-1 (10.31*2011]

WBN EEB-MS-Till-0062 Prepared By ---=!A=JC.r.,;;;____ Date '-22 -B Checked By JP;?i,.pi

~---

Date ;/J-2/4'3

~1 Page 6 The purpose of this calculation is to evaluate the adequacy of the 125VDCDiesel Generator Control Power System for compliance with FSAR and design criteria requirements for the following:

-battery sizing

-battery charger sizing

-protective device sizing

-short-circuit protection and coordination

-Appendix R power supply and associated circuits

-Reg Guide 1.75 associated circuits

-cascade fuse analysis

-voltage to components The purpose of this calculation is also to evaluate the impact of the MELB on fut.I 125V DC Diesel Generator Control Power System and demonstrate that in the event of its loss the plant's safe shutdown can be successfully achieved.

2.0 Assumptions Refer to Section 5.0 for documentation and justification of assumptions.

3.0 References and Sources of Design Input Data 3.1 WBN FSAR Sections 8.3.

3.2 Design Criteria WB-DC-30-27, "AC and DC Control Power Systems", DIMS WB-DC-30-27-1 (B26890324040), WB-30-27-2 (826900510078).

3.3 WBN Preop Test 14D R4.

3.4 TVA drawings and vendor documents listed below:

15N210-4 RF 15W814-5 RJ 1-45W727 R03 l-45W728-l R02 1-45W760-82-l R02, -2 ROl, -3 R03, -4 R02, -5 ROO, -6 R02, -11 ROO, -12 ROl, -13 ROI, -14 R02, -15 ROO, -16 R02, -20 R02, -21 ROO 45Wl761-l RM 45Wl762-l RH 45Wl763-l RK 45Wl780-l RG, -2 RD, -3 RF, -4 RF, -5 RC, -6 RE THIS PAGE ADDED BY REVISION 14

WBN EEB-MS-Till-0062 Prepared By~ Date :£.§£2 Checked By: .......... . I) .

Date: :i- z..- '..:z Page 7 45W1781-1 RN, -2 RD, -3 RG, -4 RF, -5 RC, -6 RE 45W1782-1 RE, -2 RB, -3 RD, -4 RB, -5 RB, -6 RC 45W1787-1 RG 45W2761-1 RJ 45W2763-1 RL 45W2780-1 RK, -2 RE, -3 RH, -4 RG, -5 RC, -6 RF 45W2781-1 RL, -2 RE, -3 RF, -4 RH, -5 RB, -6 RE 47E235-29 R04, -30 R03 Vendor Documents

/?.II Contract 83090 DG Manual VOl 1 & 2, TVA IDs 979, 980 (DG lA-A, lB-B, 2A-A, 2B-B); DG Manual Vol 1 & 2, TVA IDs 1548, 1549 (DG C-S) 650-242, 244; 655-241 6036B11010 RD, SHEETS 1-10 6036C04501 RB C379C11501 R904 6036C11501 R901 6036C11501 R902 6036F11502 RB 3.5 DS-ES.1.1 RS,"Substitution standard for Low-Voltage Power and control Fuses (600 Volts or Less)".

IEEE Standard 485 (1978), IEEE Recommended Practice for Sizing Large Lead Storage Batteries for Generating Stations and Substations".

3.7 SQN Calculation SQN-CPS-007 RO, "Diesel Generator Battery Capacity", B43861210901.

3. 8 SQN Calculation SQN-CPS-012 Rl, "Diesel Generator I~ If Lube Oil Pump Voltage", B87910118002.

3.9 Walkdown data for DG distribution panels included as attachment to memo from R.W. Bradford to H.B.

Bounds, dated Nov. 28, 1988, "Watts Bar Nuclear Plant-Unit 1 and 2-Walkdown of Electrical Equipment

-Walkdown Procedure WP-37 11 , C24881128629.

3.10 National Electric Code, 1987, Chapter 9, Table 8, "Properties of Conductors" (de resistance at 25° C) .

This Sheet Added By Rev 11

WBN EEB-MS-Till-0062 Prepared By: _ _?__~__.;?_'k.____ Date: 6/2-Y/t:/5""'

7 Checked By: _ _ -#-~<..-=----- Date: ~/'24!f )'b-Page 10 5.0

5. The minimum ambient temperature of the rooms containing the diesel batteries is 50° F.

Justifioation: TVA drawings 47E235-29R2 and 47E235-30RO list the average DG room temperature at 75° F and a normal minimum of so° F. Ref. DCN M11594A.

5.2 The diesel batteries shall support three start attempts; one at the beginning of its 4 hour4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months duty cycle, one at the 29 minute mark and the other at the end of the 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months .

Justification: DCN S-34918-A limits the number of starting attempts to three during the 4 hour4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months Station Blackout event. If the diesel fails to RJ°l reach 200 rpm within 5 seconds of initial start, a fail to start condition exists and the diesel is locked out, requiring a manual reset for a restart attempt. Experience with the diesel has proven that if it does not start at the initial start command, the time required for response and problem correction is significant such that it is reasonable to assume that the first restart attempt will occur in the first 30 minute period. Assuming the third and final starting attempt occurs in the final minute is conservative.

5.3 It is assumed for short-circuit analysis that the DG battery system voltage is determined by the base emf of the battery at 2.06 volts-per-cell such that the battery voltage used in analysis is 119.5V (58 cells x 2.06V).

Justification: Under short-circuit conditions, the charger voltage declines as the output is current-limited. The use of 2.06 volts per cell will provide conservative results.

This Sheet Added By Rev 19

WBN EEB-MS-Ti ll- 006 2 PREPARED BY -fJ.?t.,'){

PAGE 15 11 CHECKED BY ~--

Battery Sizing Calculation IEEE 485-1983 Work Sheet DIESEL BATTERIES SIMULTANEOUS MOTOR STARTS Period load Change Duration Time to End Capacity Required In Load of Period of Section At T Min Section Section (A) (Amps) (minutes) Size Pos Pl Section 1 - First Period Only / o~. 't I 1 A1=

10824

~ A1-0= ~ M1= T=M1 72 .33

-f00*£1 I Of.4 Section 2 - deleted for clarity

. F Section 3 ; 1* ~Ist Th s . o ree ect1ons nly IOi I 02.'24y l 1 A1 1

- . . 1oe .;~ .. A1-0 = ~ M1 = '2 -29 .

1 T;:M1 :M3 30 47.33 ~

2 A2=n.:l11s .e *&4A2-A1 = (91 .2) M2= 28 T=M2:M3 29 47.33 (1 .93) 3 A3= -&+:e

-8'1; . o4 A3-A2 = 65.0 M3= T=M3 72 .33 o.9o R/'1

.?;2. ;i I Total .. . ~

1*'26 ~

Section 4 - deleted for clarity Section 51.PS.FJ.rst Five Periods Only A1-:-

4oe;p'24 A1-o = '

.Jii* i~ (,.1i

~

1 M1= T= M1 : ~A5 240 ; 6.:: ~

2 A2=f7.~l Mi.!H7-04 A2-A1 = (91 .2) M2= 28 T='= M2 :M5 239 1 e.,'J0 (5.70) 3 A3=8'J..:lla1 .a ea e4A3-A2 = 65.0 M3= 1 T=M3 :M5 21 1 19.00 3.42 4 A4=1Pil 1i.O1Su24A4-A3 = (66.8) M4= 209 T=M4 :M5 210 19.00 (3.52) 5 A5=78.~f +M A5-A4 = 63.4 *Ms= °T=M5 72 .33

. 78* 64 0.88 Total ... 4-:88-

/.81;,

Battery Cell Size (No. Of Pos Plates) = Temp Car Factor X Aging Factor X Design Margin

). 8 b

= 1.19 x 1 .2s x 1 .ox 1 .aa ~ 85

= ~*~ Positive Plates

.,;7 P,27 THIS PAGE ADDED BY REVISION 19

ATTACHMENT 2 IEEE Std 485-1997(R2003)

IEEE Recommended Practice for Sizing Lead-Acid Batteries for Stationary Applications Extracted Pages

IEEE Std 485-1997(R2003)

(Revision of IEEE Std 485-1983)

IEEE Recommended Practice for Sizing Lead-Acid Batteries for Stationary Applications Sponsor IEEE Standards Coordinating Committee 29 on Stationary Batteries Reaffirmed 11 September 2003 Approved 20 March 1997 IEEE Standards Board Abstract: Methods for defining the de load and for sizing a lead-acid battery to supply that load for stationary battery applications in full float operations are described . Some factors relating to cell selection are provided for consideration. Installation , maintenance, qualification , testing proce-dures, and consideration of battery types other than lead-acid are beyond the scope of this recom-mended practice. Design of the de system and sizing of the battery charger(s) are also beyond the scope of this recommended practice.

Keywords: battery duty cycle , cell selection , de load, full float operation , lead-acid batteries, rated capacity, sizing , stationary applications, valve-regulated lead-acid (VRLA) cell , vented battery The Institute of Electrical and Electronics Engineers, Inc.

ISBN 1-55937-913-8 No part of this publication may be reproduced in any form, in an electronic retrieval system or otherwise, without the prior written permission of the publisher.

Copyright The Institute of Electrical and Electronics Engineers , Inc . Document provided by IHS Licensee=Tennessee Valley Authority/5919845100, Provided by IHS under license with IEEE User,,,ACBANGAL, 03/09/2004 12:55 :52 MST Questions or comments about this message: please call the Document Policy Group at 303*397-2295.

IEEE Std 485-1997 IEEE RECOMMENDED PRACTICE FOR Note that the "margins" required by 6.3.1.5 and 6.3.3 of IEEE Std 323-1 983 are to be applied during "quali-fication" and are not related to "design margin."

Table 1-Cell size correction factors for temperature Electrolyte temperature Cell size Electrolyte temperature Cell size correction correction (o F) (0 C) factor (o F) (o C) factor 25 -3.9 1.520 78 25.6 0.994 30 - I.I 1.430 79 26.1 0.987 35 1.7 1.350 80 26.7 0.980 r:

40 4.4 1.300 81 27.2 0.976

"-"- _ 72 - J .22_0 82 27.8 0.972

'{ 'I" '[ y rt" y v ~

50 10.0 1.190 A 83 28.3 0.968

.... - ... "TZ....u ,. - l.. -

-- l.. l..

A A

- ~ ~~

0.964

~

) J" ~ J~ - -~ 84 28.9 60 15.6 1.110 85 29.4 0.960 65 18.3 1.080 86 30.0 0.956 66 18.9 1.072 87 30.6 0.952 67 19.4 1.064 88 31.1 0.948 68 20.0 1.056 89 31.6 0.944 69 20.6 1.048 90 32.2 0.940 70 21. 1 1.040 95 35.0 0.930 71 21.7 1.034 100 37.8 0.910 72 22.2 1.029 105 40.6 0.890 73 22.8 1.023 110 43.3 0.880 74 23.4 1.017 11 5 46.1 0.870 75 23.9 1.011 120 48.9 0.860 76 24.5 1.006 125 51.7 0.850 77 25 .0 1.000 NOTE-This table is based on vented lead-acid nominal 1.215 specific gravity. However, it may be used for vented cells with up to a 1.300 specific gravity. For cells of other designs, refer to the manufacturer.

6.2.3 Aging factor As a rule, the performance of a lead-acid battery is relatively stable throughout most of its life, but begins to decline with increasing rapidity in its latter stages, with the "knee" of its life versus performance curve occurring at approximately 80% of its rated performance.

IEEE Std 450-1995 recommends that a battery be replaced when its actual performance drops to 80% of its rated performance because there is little life to be gained by allowing operation beyond this point. Therefore, to ensure that the battery is capable of meeting its design loads throughout its service life, the battery's rated capacity should be at least 125% ( 1.25 aging fac tor) of the load expected at the end of its service life.

Exceptions to this rule exist. For example, some manufacturers recommend that vented batteries with Plante, modified Plante, and round plate designs be replaced when their measured capacity drops below 100% of R

Co pyright The Institute of Electrical and Electronics Engineers , Inc. Document provided by IHS licensee=Tennessee Valley Authority/5919845100, Provided by IHS under license with IEEE User=ACBANGAL, 03/09/2004 12:55 :52 MST Questions or comments about this message: please call the Document Policy Group at 303-397-2295.

Tennessee Valley Authority, 1101 Market Street, Chattanooga, Tennessee 37402 CNL-15-220 October7, 2015 10 CFR 50.36 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001 Watts Bar Nuclear Plant, Unit 2 Construction Permit No. CPPR-92 NRC Docket No. 50-391

Subject:

Watts Bar Nuclear Plant Unit 2, Response to Request for Additional Information - Developmental Revision I Technical Specification Section 3.8 -

Diesel Generator Batteries

References:

1. Electronic Mail from J. Poole (NRC) to G. Arent (TVA), Batteries, dated October 5, 2015

2. TVA Letter to NRC, Watts Bar Nuclear Plant Unit 2 - Submittal of Developmental Revision I of the Unit 2 Technical Specification & Technical Specification Bases and Developmental Revision D of the Unit 2 Technical Requirements Manual and Technical Requirements Manual Bases, dated June 16, 2014 [ML14169A525]

The purpose of this letter is to respond to a request for additional information (RAI) provided in Reference 1. Tennessee Valley Authority (TVA) was requested to confirm that the Diesel Generator batteries are designed to operate at 50o Fahrenheit (F). This question was identified by the Nuclear Regulatory Commission during their review of Technical Specification (TS) 3.8 provided in Development Revision I of the Watts Bar Nuclear Plant Unit 2 TSs (Reference 2).

The enclosure provides TVAs response to the Reference 1 RAI regarding batteries.

There are no new regulatory commitments associated with this letter. Please direct any questions concerning this matter to Gordon Arent at (423) 365-2004.

U.S. Nuclear Regulatory Commission CNL-15-220 Page 2 October 7, 2015 I declare under penalty of perjury that the foregoing is true and correct. Executed on the 7th day of October 2015.

Respectfully, Digitally signed by J. W. Shea J. W. Shea DN: cn=J. W. Shea, o=Tennessee Valley Authority, ou=Nuclear Licensing, email=jwshea@tva.gov, c=US Date: 2015.10.07 19:14:15 -04'00' J. W. Shea Vice President, Nuclear Licensing

Enclosure:

Response to NRC Request For Additional Information - Diesel Generator Battery Temperature cc (Enclosure):

U.S. Nuclear Regulatory Commission, Region II NRC Senior Resident Inspector - Watts Bar Nuclear Plant, Unit 2 NRC Project Manager - Watts Bar Nuclear Plant, Unit 2

Enclosure Response to NRC Request For Additional Information - Diesel Generator Battery Temperature

Background

By letter dated June 16, 2014, Tennessee Valley Authority (TVA) submitted the Watts Bar Nuclear Plant (WBN) Unit 2 Developmental Revision I of the Technical Specifications (TS) and TS Bases, and Developmental Revision D of the WBN Unit 2 Technical Requirements Manual (TRM) and TRM Bases to the Nuclear Regulatory Commission (NRC) (Reference 1). By electronic mail (email) dated October 5, 2015, the NRC provided a request for additional information (RAI) regarding TS Section 3.8 of Developmental Revision I (Reference 2).

The following response to the Reference 2 RAI addresses the NRC staff concerns related to the design of the Diesel Generator (DG) batteries.

NRC RAI TS 3.8.6.3 establishes battery operability based on battery cell parameters and average electrolyte temperatures for vital and DG batteries. If the average electrolyte temperature of the representative cells is outside the lower limit (< 60oF for vital batteries and < 50oF for DG batteries), the battery is considered inoperable. The staff requested information about Station battery sizing and testing criteria for 60oF ambient temperature and DG battery at 50oF ambient temperature.

The applicant provided details on correction factors for station batteries for temperature range at and above 60oF and correction factors for DG batteries for temperature range at and above 60oF and NOT 50oF. The staff recommends that the applicant confirm that the DG batteries are designed for operating at 50oF.

TVA Response Based on TVAs review of 125VDC Diesel Generator Battery sizing analysis calculation WBNEEBMSTI110062; the design temperature used for sizing the DG batteries is 50oF. provides pages from the calculation confirming the use of 50oF The cell sizing factor for 50oF corresponds to 1.19 and is obtained from Table 1 of IEEE Standard 485, IEEE Recommended Practice for Sizing Lead-Acid Batteries for Stationary Applications (Attachment 2). Therefore, TVA confirms that the DG batteries are designed for operating at 50oF.

References

1. TVA Letter to NRC, Watts Bar Nuclear Plant Unit 2 - Submittal of Developmental Revision I of the Unit 2 Technical Specification & Technical Specification Bases and Developmental Revision D of the Unit 2 Technical Requirements Manual and Technical Requirements Manual Bases, dated June 16, 2014 [ML14169A525].

2. Email from J Poole (NRC) to G. Arent (TVA), Batteries, dated October 5, 2015.

CNL-15-220 E-1

ATTACHMENT 1 TVA Calculation WBNEEBMSTI110062, 125VDC Diesel Generator (DG) Control Power System Evaluation Extracted Pages

NPG CALCULATION COVERSHEET I CTS UPDATE Page 1 REY 0 EDMS/RIMS NO. CTSJYPE; EDMS TYPE:

90021480004/826 900202 406 calculation CALCULATIONS (NUCLEAR) cak: Trtle:

125VDC DIESEL GENERATOR (DG) CONTROL POWER SYSTEM EVALUATION BBANQH NVMBER CYB REV NEW REV CALCID NUC WBN EEB WBNEEBMSmt0062 028 CTS UPDATE ONLY 0 NO CTS CHANGES

- ~ ~__..-'.v 10(

(Verifier and Approval Signatures Not Required) (For calc revision, has been and no CTS changes required)

Y.!::i1I (check one) SVSTEMS UNIDS o181. 1 O. 2 0. 3 D I

082 NIA APPLICABLE DESIGN pOCUMEN!(§)

I I pCN.E[)C NIA CLASS!RCADON See Bev Log NIA E OUAUJY SAEED' RELATEP7 UNVEBIREP SPECIAL REQUIREMENTS 1 oeslGN OIJJPUT SAR/TS and/or !SfSI

.ei:1...t.TED? (If yes, QB = yes) a"'" JMPTION &NrvnA uumNG

I ..TT: ** " ,

~ -* - .. -*

Yes 181 Non I I

£ , K Yes 181 No L I Yes D No 181 Yes D

No 181 Yes D No~ Yes D No 181 CALCULATION NUMBER BEOl.JESTOR PBEPABING QISC!PUNE VERIFICATION METHOD

1NEW METHOD OE AN6LYS!S Name: vupetel PHONE: 301*228-7658 EEB Design Review 0 Yes 181 No PREPARER v.r:NAMEAN~Sl~./7 DATE CHECKER (PRl~NAMEA~SIGN) . DATE VlnuPatel ~cc.>CY to/>/,?_ DSBhatla (\,(~~ 1o/2Ji,_

VERIFIER (PRINT NAME ~G~ h . - DATE APPROVAL (PRINT NAME AND SIGN) DATE FAJl.~oQ SoF1 { fl- d'- - 10/tofrv ~Cox ~~ ~

10

//1fi2 I

STATEMENT OE PRQBL.EMIABSTRACT STATEMENT of PROBLEM:

Verify the adequacy of the design and compliance with design criteria and SAR requirements. Review and document and Impact.

ABSTRACT:

This calculation evaluate the adequacy of the 125 VDC DG Control Power System battery sizing, charger sizing, protective devlc1 sizing, short circuit and cpordlnation, Appendix R, fleg. Gulde 1.75 - Associated Circuits, cascade fuses and maximum voltag.e to the control circuit components. Equipment submerged due to MELB event Is identified

and the impact of Its submergence on the 125 VDC DG Control Power System Is evaluated in Appendix I. See Section 8.0 and 9.0 for results and conclusions.