ML20247M420
| ML20247M420 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 07/26/1989 |
| From: | William Cahill TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| TXX-89488, NUDOCS 8908020096 | |
| Download: ML20247M420 (11) | |
Text
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M L
Log # TXX-89488 1
C File # 10010 C
C 918 Ref. # 10CFR50.34(b) 7UELECTRIC WiHimmJ.CahiH Jr.
Ltecutive Vice Presidmt U. S. Nuclear Regulatory Commission Attn: Document Control. Desk Washington, D. C.
20555
SUBJECT:
COMANCHE PEAK STEAM ELECTRIC STATION (CPSES)
DOCKET NOS. 50-445 and 50-446 ADVANCE FSAR SUBMITTAL DESIGN OF RESET CIRCUITS OF ENGINEERING SAFETY FEATURES Gentlemen:
The enclosure to this letter provides an advance submittal of FSAR changes related to the design of reset circuits of Engineering Safety Features (ESF).
These changes will be included in a future FSAR amendment.
In order to facilitate NRC staff review of these changes, information related to the FSAR change (Enclosure 1) is organized as follows:
1.
Draft revised FSAR pages, with changed portions indicated by a bar in the margin (denot ed as " draft"), as they are to appear in a future amendment (additional pages immediately preceeding and/or following the revised pages are provided if needed to understand the change).
2.
A description / justification of the revised FSAR.
3.
A copy of related SER/SSER sections.
4.
The bold / overstrike version of the revised FSAR pages referenced by the description / justification for each item identified above.
The bold / overstrike version facilitates review of the revisions by highlighting each addition of new text in bold type font and overstriking with a slash (/) the portion of the text that is deleted.
8908020096 890726 O
PDR ADOCK 05000445 i
A PDC
' \\
400 North Olive Street LB 81 Dallas, Texas 75201 J
-/:
TXX-89488 July 26, 1989 Page 2 of 2 l-F Per the enclosed FSAR change, clarification has been provided to indicate that upon resetting of the Westinghouse supplied ESF Actuation Signal (ESFAS),
equipment must be subsequently reset at a lower level (e.g. at the individual component controis, by resetting thc_ sequencer, etc.).
The specific loads associated with the Westinghouse supplied ESFAS, which may reposition upon an ESFAS reset, are listed in Enclosure 2.
In addition, loads that may reposition (i.e. depending on the process demand) upon-resetting the sequencer are listed in Enclosure 3.
TU Electric requests that the NRC perform _an expedited review of the above FSAR changes and inform us as to their acceptability.
Sincerely, William J. Cahill, Jr.
4 By:
D. R. Woodlan Docket Licensing Manager VPC/vid Enclosures c - Mr. R. D. Martin, Region IV Resident Inspectors, CPSES (3)
E'
, to.TXX-89488 July 26, 1989 Page 1 of 6 Advance FSAR Change n' lated'to Design of Reset Circuits of Engineering Safety Features and Supporting Documentation Item I..
-Draft Revised FSAR Pages:
- p. 2
' Item 2 Description / Justification for
- p. 3 FSAR. Change Item 3 Related SER/SSER Pages' pp. 4 and 5 Item 4-Bold / overstrike version of the
- p. 6 FSAR pages 4
1
_E._
_________________________m___________.._
_____._______________,.__J
., -to TXX-89488'
' :l July-26,1989 '
CPSES/FSAR.
,. Page.2 of. 6 5).
-The instrumentation systems which initiate
. Containment Ventilation Isolation and are part of ESFAS are qualified to Class 1E criteria.
6)
Overriding or resetting an ESFAS signal does not cause any' equipment to change position.
Equipment DRAFT must be subsequently reset at a. lower level (e.g..-
at the individual component controls, by resetting the sequencer, etc.) before the equipment will reposition.
The CPSES design per items 1), 3) and 6) above shall'be verified as part of the Preoperational Test Program.
\\
032-138
CPSES FSAR AMENDMENT 77 e Enclosure 'l. to TXX-89488 DETAILED DESCRIPTION Page1.%f L o July. 26,1989 f :Page.3 of 6
)
FSAR Page
.(31 amended)-
Group Description
]
L:
.Q&R'032-138 2
Engineered Safety Features (ESF) reset controls in which some non-safety related equipment may' change position.
Revision:
Similar:to the NRC request in IE Bulletin 80-06 for operating facilities, the NRC requested that TU Electric review all safety-related equipment to determine whether or.not overriding or resetting an-ESFAS signal, all safety-related equipment remains in:
- its emergency mode.
In the original response, TV Electric stated that neither condition would cause any equipment to change position. However, it was recently identified that some non-safety equipment will change position after an ESFAS reset. Design modifications are' being implemented such.that no equipment will change position when an ESFAS signal is reset. In addition, the response was clarified to show that it is acceptable for equipment to change position when.
subsequent action is taken at a lower level, such as the operation of individual controls of equipment, the resetting of the sequencer, etc..
FSAR Change Request Number: 89-540 Related SER Section: 7.3.2.1 SER/SSER Impact: No
closure 1 to TXX-89468 July 26,1989 Page 4 of 6 Thechilledwaterrecirculationpumpsstartwhentheyreceiveasafetyinjection or blackout sequence signal.
{1 7.3.1.12 Containment Ventilation isolttion Acutation j
The containment purge isolation valves closo automatically on detection of high-radiation leve s,l.a manual containment sprpy actuation signal, or a safetyinjectionsigna The containment pressure relief system relieves excess containment pressures caused by temperature transients or air leakage from pneumatic actuators during normal operation.
The pressure relief containment isolation valves automatically close on a contain:2ent ventilation isolation signal.
7.3.1.13 Combustible Gas Control Actuation Following a ORA, hydrogen gas may be generated inside the containment. To ensure that the hydrogen concentration is maintained on a safe level, electrical, redundant hydrogen reces41ners and a backup hydrogen purge system are provided.
Each recombiner is provided with a separate power panel and control panel, and each is powered from a separate safeguard bus. Operation of the recombiner is performed manually from a control panel located in an accessible area outside the containment. The power panel for the recombiner contains an isolation transforiser plus an SCR controller to regulate power into the recombiner.
7.3.2 Resolution of Concerns Related to ESFAS 7.3.2.1 Loss of Safety Function After Roset x
As was dona for operating reactors through IE Bulletin 80-06, the staff has
(
requested that the applicant review all safety equipment to determine which, if any, safety functions might be unavailable after reset, and what changes would be implemented to correct any problems.
The applicant provided a response stating that he has reviewed the design and determined that it is in conformance with the applicable guidelines, except for one case that contravenes the staff position.
The logic to initiate containment ventilation isolation uses a radiation high-level signal and ESFAS T signal input to a retentive manery with actuation block gate. Thus a reset of a high-radiation signal would block the ESFAS input signal.
The applicant will i
modify the design se that the reset of one input signal will not block systes
)
actuation by the other in have riot been completed. put signal. At this time, the design modifications The staff will review the design for this system i
before the issuance of the Operating License.
The appifcant further committed that a test will be conducted during the preoperational test program to confirm the conclusion of this review.
The staff finds this acceptable.
7.3.2.2 Level Measurement Errors Due to Environmental Temperature Effacts on Level Instrument Reference Legs The staff asked the applicant to evaluate the effects of high temperatures in reference legs of water level measuring instruments after high-eneig-line breaks.
This issue was addressed for operating reactors through IE w!!*-
tin 79-21.
In response to these concerns, 'the applicant has committed to i
7-17
_ to TXX-89483 July 26,1989 Pbge 5 of 6 7
INSTRUMENTATION AND CONTROLS
- 7. 3 kncineered-Safety-FeaturesActuationSystem 7.3.1 Description 7.3.1.5 Feedwater Line Isolation Actuation As a result of the staff's review of current operating Itcense applications for Westinghouse plants, a concern about control and protection systems inter-action has been id9ntified which was not addressed jn the earlftr review.
The concern relates to steam generator level measurement channels which are used for both protection and control. The protection system initiates feedwater isolation when 2 of 3 channels indicate high. level.
Since one of these level channels is used for control, the failure of this channel would result in steam generator overfill by action of the level control system. As a consequence of this failure, the two remaining channels must operate to provide the required protective action.
This does not satisfy the requirements for control and pro-taction system interaction in that the remaining channels of the protection system must satisfy the single failure criterion. Therefore, the staff has requested that the applicant respond to this concern and the staff will address its resolution in a future supplement to the SER.
7.3.2 Resolution of Concerns Related to ESFAS
(;
7.3.2.1 Loss of Safety Function After Roset x
In the SER, the staff indicated that the logic to initiate containment ventila-tion isolation uscs a radiation high-level signal and an E5FAS signal input to a retentive memory with ac;.uation block gate. Thus a reset of a high-radiation signal would block the ESFAS input signal.
In Amendment 29 of the FSAR, the applicant provided a design change to address this issue.
The high radiation signal was changed to a pulsed s'gnal. If the gate was set because of a high-radiation signal, resetting the gate after the pulse would not invoke the actuation block feature, and thus it would initiate protective action on a sub-sequent ESFAS signal. The staff finds that the applicant's modification is acceptable, and therefore, this issue is resolved.'
- 7. 7 Control Systems Mst Reevired for Safety 7.7.2 Conclusions In the SER tt was noted that the staff had requested a review by the applicant to determine whether the harsh environments associated with high-energy line breaks might cause control system malfunctions and result in consequences more severe than those calculated in the Chapter 15 analp es or beyond the capability of operators or safety systems.
The applicant has performed a review to evaluate the impact of control system failures as a consequence of harsh environments due to high-energy ifne breaks.
Based on this review, t.h. spplicant concludes that the following failures could f(
occur and that the consequences of these failures are not bounded by the safety analysis provided in Chapter 15 of the FSAR.
Comanche Peak SSER #2 7-1
Enclo'sur.e 1 to.TXX-89488 July. 26, '1989 o
E Pag'e 6 of-6 CPSES/FSAR l'
5)
The instrumentation systems which initiate Containment Ventilation Isolation and are part of ESFAS are qualified to Class IE criteria.
l' 6)
Overriding or reset +.ing an ESFAS signal does not cause any equipment to change position. Equipment must be subsequently reset at a lower level (e.g.,
at the individual component controls, by resetting the sequen er, etc.) before the equipment will reposition.
Edd Fiddtd 7/2/Z/ dHddf Bl ddfd 61 The CPSES design per items 1), 3) and 6) above shall be verified as part'of the Preoperational Test Program.
032-t#B13F l
H lEn losure' 2 to TXX-89488 -
July:26,R1989
;iPagh:1 of'1 NON-SAFETY RELATED EQUIPMENT CHANGING POSITION
' ~
(WESTINGHOUSE) is EQUIPMENT (1)
MCC HP/KVA/KW COMMENTS Vent Control Unit Cooler 1EB3-2
.33HP 2
'MOV'l-HV-6074
. Vent Control Unit Cooler 1EB3-2
.33HP 2
MOV 1-HV-6076 Vent Control Unit Cooler
.33HP 2
.MOV 1-HV-6078 Vent Control Unit Cooler IEB4-2
.33HP 2
MOV 1-HV-6075 Vent Control Unit Cooler 1EB4-2
.33HP 2
'HOV 1-HV-6077 Vent Control Unit Cooler 1EB4-2
.13HP 2
'MOV 1-HV-6079 Containment LTG XFMR 1EB4-2 45KVA
-2 CPI-ELTRNT-19 Containment LTG XFMR 1EB3-2 45KVA 2
'CP1-ELTRNT-18 Vent Chilled Water XEB1-1 125HP 3
Recirc. Pump
-CPX-CHAPCP-01 Vent Chilled Water XEB2-1 125HP 3
Recirc Pump CPX-CHAPCP Vent Chilled Water XEB1-2 125HP 3
Recire Pump 1
CPX-CHAPCP-03 Vent Chilled Water XEB2-2 125HP 3
Recirc Pump
)
.CPX-CHAPCP-04 i
NOTES:
]
- 1. Includes Equipment Associated with Both Train A and Train B.
2.; Current design includes two breakers in series in the power feed and an "SI" contact in the control circuit.
Proposed fix is to remove the "SI" contact.
- 3. Current design is control circuit tripped on "SI" signal.
Proposed fix is the addition of sequencer auto lockout (SIS /AL) contact to the auto start control q
circuitry.
l-
- Enclosur -3'to TXX-89488 JJuly 26, 1989-
' ~ Paga,1 of 2 NON-SAFETY RELATED EQUIPMENT CHANGING POSITION (SEQUENCER);
1 EQUIPMENT (1.2)
MCC HP/KVA/KW COMMENTS Containment Vent Damper 125VDC 1-HV-54050-1 Containment Vent Damper.
125VDC 1-HV-5405D-2 Containment Vent Damper 125VDC 1-HV-5409D-1 Containment. Vent Damper 125VDC
'1-HV-5409D-2' Containment Vent Damper 125VDC 1-HV-5413D-1
' Containment Vent Damper 125VDC 1-HV-5413D-2
. Containment Vent Damper 125VDC 1-HV-54170-1 Containment Vent Damper 125VDC HV-5417D-2 Battery RM 1-3(c)
IEB3-1 1.5HP EXH FAN-11 Battery RM 1-3(c) 1EB4-1 1.5HP EXH FAN-12 Aux Jacket Water _ Pump IEB4 75HP Aux Lube Oil Pump IEB4-4 60HP Jacket Water Heater IEB4-4 75KW Lube Oil Heater IEB4-4 48KW
~D.G. Air Compressor #3 1E84-4 30HP D.G. Air Compressor #4 IEB4-4 30HP
.D.G. Prelube Pump IEB4-4 15HP i
l
_=___ - _ _ - _
,c-,
f '
[cEnclosure 3 to.TXX-89488s
~A July,26/ J989-
'.Page 2 of 2
. NON-SAFETY RELATED EQUIPMENT CHANGING POSITION (SEQUENCER)
I~
EQUIPMENT (1.2)
MCC HP/KVA/KW COMMENTS
- 3HP-Compressor Aftercooler #3 IEB4-4 IHP Compressor l Aftercooler #4-IEB4-4 IHP
-),
. Fuel 011LDrip Return Pump 21EB4-4 IHP Aux Jacket Water Pump 1EB3-4 75HP
- Aux Lube Oil Pump IEB3-4 60HP
'--Jacket Water. Heater
-IEB3-4 75KW-Lube Oil Heater.
-IEB3 48KW
- D.G., Air Compressor #1' IEB3-4, 30HP 1D.G. Air Compressor #2 1EB3-4 30HP.
. D.G; Prelube; Pump.
1EB3-4 15HP Jacket?Wtr: Keep Warm Pump IEB3-4 3HP Fuel' Oil Booster Pump
'IEB3-4 3HP
- Fuel Oil Drip Return-Pump IEB3-4 IHP
' After' Cooler #1 IEB3-4 1HP
' After Cooler #2
'1EB3-4 IHP
- NOTES:
~1. Includes: equipment associated with both Train A and Train B
- 2.-Equipment which may reposition upon reset of the sequencer.
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