ML20128F438
| ML20128F438 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 10/01/1996 |
| From: | Terry C, Walker R TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| TXX-96475, NUDOCS 9610080073 | |
| Download: ML20128F438 (7) | |
Text
-
mammmmmmm,
Log # TXX 96475
==
File # 916 (3/4.7)
"""" 7 10010 1
Ref. # 10CFR50.90 r
=
10CFR50.36 illELECTRIC 9
$1,,,
October 1, 1996 a,
U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555
SUBJECT:
COMANCHE PEAK STEAM ELECTRIC STATION (CPSES)
DOCKET NOS. 50 445 AND 50 446 ADDITIONAL INFORMATION FOR LICENSE AMENDMENT 96 004 UNINTERRUPTIBLE POWER SUPPLIES (UPS) HVAC SYSTEM ADDITION OF FAN C0IL UNITS TO TECHNICAL SPECIFICATIONS REF:
TU Electric letter logged TXX 96405, dated July 10,1996, from C. L. Terry to the NRC 4
Gentlemen:
By the above referenced letter TU Electric submitted license amendment request 96 004 to amend the CPSES Unit 1 Operating License (NPF 87) and CPSES Unit 2 Operating License (NPF 89) to incorporate the changes
]
associated with addition of train oriented UPS Fan Coil Units. These Fan Coil Units are redundant to the existing Air Conditioning Units in the UPS HVAC System.
4. " DESCRIPTION AND ASSESSMENT" pages 4 and 7 of 13 to 1
TXX-96405 (above reference), provides the discussion on the enhancement to the ability of CPSES to meet the station blackout requirements for the UPS HVAC System.
Further clarifications are provided by an attachment to this transmittal to assess the UPS HVAC System's ability to cope with a station blackout.
Should you have any questions, please contact Mr. Manu C. Patel at (817) 897-0139.
Sincerely, d'. 6. Q DD7i ' ;
C. L. Terry
% b-6 By:
g' ', dn qO Roger D. Walker egu atory Affaks Manager PDR DO 0500 445 P
PDR P.O. Box 1002 Glen Rose, Texas 76043
~,_ _
i i
TXX 06475 Page 2 of 2 i
l MCP/
Attachment c-Mr. L. J. Callan, Region IV Mr. J. I. Tapia, Region IV Mr. T. J. Polich, NRR
?
Resident Inspectors, CPSES l
3 Mr. Arthur C. Tate Bureau of Radiation Control i
Texas Department of Public Health 1100 West 49th Street Austin, Texas 78704 1
J i
i 1
)
4 l
1 Attachment to TXX 96475 Page 1 of 2 UPS ROOM VENTILATION AND STATION BLACK OUT (SBQ1 In the Station Blackout (SBO) scenario under consideration, both units may be affected by the loss of offsite power; however, at least one emergency diesel generator on one of the units (the non SB0 unit) is assumed to start and operate. The UPS A/C system contains two 100% capacity air conditioning (A/C) units powered by common electrical distribution equipment. This arrargement ensures that one A/C unit will receive power from an operating i
emergency diesel generator from the Non SB0 Unit.
Each A/C unit is supplied with condenser cooling water from either Unit I er Unit 2 Component Cooling Water (CCW). During normal operation, only one condenser cooling water path per A/C unit is open. As a result, cooling water may be lost during an SB0 i
a f
if it is aligned to the SB0 Unit.
Fans on the cooler, however, will continuously circulate air throughout the UPS & Distribution Rooms with or j
withcut condenser cooling water.
To assess the effects of a loss of cooling to the UPS & Distribution Rooms, l
the maximum steady state temperatures were previously calculated (Ref.
i TXX 92447) using the methodology defined in Appendix H of NUMARC 87 00, i
modified by taking credit for the circulation of air by the fans powered from a diesel generator on the Non SB0 Unit. An initial temperature of 95'F was assumed in this calculation based on one year of Unit 1 operating l
experience and administrative controls that ensure the area temperature i
remains below this assumption. The maximum steady state temperature was calculated to be no greater than 121.8'F, provided that the UPS room doors j
were opened within 30 minutes after the station blackout.
)
In order to increase the reliability of the UPS HVAC system and reduce the i
possibility of a forced two Unit shutdown as a result of UPS HVAC system j
failure, Design Modification 92 071 was initiated to add a new safety related, IEEE Class 1E Fan Coil Unit (FCU) to each of the four (4) UPS &
5 Distribution Rooms.
Each FCU is powered and cooled by the same Unit and l
train as the UPS it serves.
This change was communicated in TXX 96405 and, as stated in that transmittal, the new FCUs were considered to be enhancements to the ability of CPSES to cope with a Station Blackout.
The applicability of the NUMARC methodology to this design and some of the l
assumptions in the calculation were re examined.
During this process, it l
was discovered that electrical heat loads used in the original UPS SB0 i
loss of ventilation analysis did not include all applicable electrical equipment.
In order to address these higher heat 1c, ads, a plant specific analysis was performed to determine the 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> peak temperature and to provide time dependent parametric information.
Based on this latest analysis, it is concluded that CPSES has been and remains capable of coping with a Station Blackout for 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />,. This analysis does not assume that the room doors are initially open or that they i
must be opened during the coping period.
]
}
I
i Attachment to TXX 96475 Page 2 of 2 1)
Historical data concerning the normal operating temperatures of the UPS & Distribution Rooms indicate that these areas have normally been maintained below 86'F.
Based on the CPSES UPS HVAC design prior to the installation of any of the FCUs and assuming 4
an initial temperature of 86'F, the analysis shows that the room temperatures remain below 120'F during the 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> coping period.
As discussed above, one train of UPS HVAC fans continues to j
circulate air throughout the rooms during the S30.
2)
Because all four FCUs will normally be operating, at least one of the FCUs (the FCU which is the same unit and train as the operating Emergency Diesel Generator) may be assumed to operate i
during an SBO. Based on the CPSES UPS HVAC design after the FCUs are installed and assuming an initial temperature of 95'F, the analysis shows that the room temperatures remain below 120'F during the 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> coping period. This analysis also assumes that the available train of UPS HVAC fans (which will start automatically) circulate air throughout the rooms durdi, the SBO.
I TV Electric has decided to replace the Westinghouse and Elgar inverters, 4
which are located in the UPS & Distribution Rooms, with 10KVA units from another vendor.
The Unit 1 inverters will be replaced in 1RF05 per DM 96-013. Although these inverters are more efficient and have a higher 1
i qualification temperature, they also result in a higher heat load on the air l
conditioning system.
Even with this additional heat load, the parametric study described above confirms that the UPS room temperatures will remain below the qualification limits of the inverters for the duration of the SB0 using the same assumptions as 2) above (an initial room temperature of 95'F i
or less, cooling by one FCU and air circulation by the fans in one UPS A/C 4
train).
1 The temperature history of the UPS & Distribution rooms, along with the l
administrative controls already in place, provide high confidence that CPSES 4
will maintain the temperature in the UPS rooms below 95'F during normal plant operation. The installation of the FCUs will be completed prior to placing the new 10KVA inverters in service.
4 i
A
NCTWPLSS.001 TU ELECTRIC PACE:
1 DATE: 07-25-96 TOTAL PLANT KYSTEM TIME: 19:35:50 SHORT DESCRIPTION CDF PRINT RES. ORC: RSNm COMID: 25404 STATUS: INC LIC CONTACT: CLM SC M COMPLETION DATES UNIT 1 UNIT 2:
REGO COMPLETION DATES UNIT 1:
UNIT 2:
TITLE: STATION BLACKOUT COPING ASSESSMENT DESCRIPTION:
Station bimekout response omsipment has been assessed for the ef fects of loss of ventilation for a four hour duration. This equipment will remain operable for S8O temperatures for the required duration.
{perephrased for clarity}
RES. ORC: Pumm COM1D: 25414 STATUS: INC LIC CONTACT: 08 SCHD COMPLETION DATES UNIT 1:
UNIT 2:
REGO COMPLETION DATES UNIT 1:
UNIT 2:
TITLE: LOSS OF 0FFSITE PONER PROCEDURE FOR STATION BLACKOUT (10CJR58.63)
DESCRIPTION:
Revise ABN-691 to direct operators to open the UPS distribution room doors within 30 minutes of a station blackout if the UPS airconditicining units are not operating to equalize the touperatures in the area.
RES. CRC: EEmu COMID: 25843 STATUS: INC LIC CONTACT: VPC/ JET SCHO COMPLETION DATES UNIT 1:
UNIT 2:
REGO COMPLETION DATES UNIT 1 UNIT 2:
TITLE: BATTERY CALCULATIONS (STATION BLACKOUT)
DESCRIPTION:
The following assumptions were used to determine bettery capecity for
$80.
a.
Minimum electrolytic temperature of 65 degrees F, based the $80 calculated minimme temperature of 67 degrees F (reference calculation ME-CA-8385-3027 Revisione) l b.
Bettery sizing in accordance with IEEE 485.
c.
Aging factor of 1.25 based on IEEE 485.
d.
Temperature correction factor of 1.88 based on IEEE 485.
e.
Design margins of 25 and 35 percent for Class IE betteries based on the S80 analysis, and f.
No load shedding mesumed.
RES. ORC: Puum COMID: 26523 STATUS: INC LIC CONTACT: 08 SCHO COMPLETION DATES UNIT 1:
UNIT 2:
REGO COMPLETION DATES UNIT 1:
UNIT 2:
TITLE: UPS PROCEDURE DURING BLACKOUT (SSER 26)
DESCRIPTION:
The applicant committed to revise procedures to direct operators to open
.. MORE..
l
. ~ - -
- ~.
-. -. ~...-
NCTWPLSS.Re1 TU ELECTRIC PACE:
2 DATE: 87-25-96 TITAL PLANT SYSTEN TINE: 10:32:50 SHORT DESCRIPTION CDF PRINT RES. ORC: Puma CONID: 26523 STATUS: INC LIC CONTACT: 08 DESCRIPTION:
the UPS distribution room doors within 39 minutes of a station blackout if the UPS air conditioning units are not operating (i.e., single failure of the associated train on the unit that is not blacked out).
RES. ORC: Puum CONID: 26524 STATUS: INC LIC CONTACT: OB SCle COMPLETION DATES UNIT 1:
UNIT 2:
REGE COMPLETION DATES UNIT 1:
UNIT 2:
TITLE: UPS ROON ADMIN. CONTROLS (SSER 26)
DESCRIPTION:
The applicent further indicated that adminstrative controls will be provided to monitor the UPS room temperature on a per-shift basis so as to ensure that the initial room temperates will remain at or below that used in the inoperature calculation for en $30 event.
um Ele OF REPORT mm 5
k b
NCTWPLSS.Re1 TU ELECTRIC PAGE:
1 DATE: 89-25-96 TSTAL PLANT SYSTEN COMPtITNENT LIST REPORT TINE: 10:35:50
'un' IMICATES PRINTED ComtITNENTS CoretIT NUPSER CoretITMNT DETAIL um 25404 STATION KACKOUT COPING ASSESSENT em 25414 LOSS OF OFFSITE POWER PROCEDURE FC2 STATION K ACKOUT (19CFR50.63) um 25043 BATTERY CALCULATIONS (STATION K ACK0UT) TION K ACKOUT (19CFR50.631 mm 26523 UPS PROCEDURE DURING K ACKOUT ($$ER 26) TION K ACKOUT (19CFR50.63) um 26524 UPS ROON ADMIN. CONTROLS (SSER 26)R 26) TION KACKOUT (IDCFR50.63) um Em 0F REPORT n=
li 1
l b
i L
i L
L
- -