ML19331C648
| ML19331C648 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry  |
| Issue date: | 08/12/1980 |
| From: | TENNESSEE VALLEY AUTHORITY |
| To: | |
| Shared Package | |
| ML19331C645 | List: |
| References | |
| NUDOCS 8008190258 | |
| Download: ML19331C648 (16) | |
Text
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i ENCLOSURE 1 1
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PROPOSED CHANGES TO TECHNICAL SPECIFICATIONS I
(TVA BFNP TS 144) 1 BROWNS FERRY NUCLEAR PLANT I
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e UNITS 1 Any g PROPOSED CHANGES J
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o Minimum No.
TAELS 3.2.A (Centinued)
~.
Instrument Channels Operable per Trip Sys(1)
Function Trip Level Setting Action (1)
Remarks 2 (10)
Instrument Channel -
< 200 F B
1.
Above trip setting initiates 0
Xain Steen Line Tunnel Mhin Steam Line ~ leakage alarm Ftch Temperature 2
Instrument Channel -
160 - 180 F C
1.
Above trip 9etting initiates 0
Reactor Water Cleanup Isolation of Reactor Water Systen Floor Drain High Cleanup Line from Reactor and Temperature Reactor Water Return Line.
2 Instrument Channel -
160 - 180 F C
1.
Same as above 0
Reactor Water Cleanup Syster. Space High Temperature gn cn 1
Instrument Channel -
< 100 nr/hr or downscale G
1.
1 upscale or 2 devnscale vill
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Reactor Building Venti-Initiate SGTS a.
lation High Radiation -
b.
Isolate reactor zone and Reactor Zone a
refuleing floor.
c.
Close atmosphere control syste=.
1 Instrument Channel -
< 100 mr/hr or downscale F
1.
1 upscale or 2 downscale vill
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Reactor Building Venti-a.
Ini.tiate SGTS.
lation High Radiation b.
Isolate refueling floor.
Refuleing Zone c.
Close atmosphere control systen.
2 (T)(8) Instrument Channel Charcoal Heaters < 2000 H and 1.
Belov 2000 erb, trip setting charcoal SGTS Flov - Train A cDn R. H. Heaters < 2000 (A or F) heaters vill turn on.
Heaters ern 2.
Below 2000 cfm, trip setting R. H.
heaters vill shut off.
2 (T)(8) Instrument Channel Charcoal Heaters < 2000 H and 1.
Below 2000 cfm, trip sotting charcoal SGTS Flev - Train 3 ccn R.H. Heaters 7 2000 (A or F) heaters vill turn on.
Heaters ef=
~
2.
Belov 2000 cfm, trip setting R.H.
heaters will shut off.
2 (7)(8) Instrument Channel Charcoal Jfeaters< 2000 cfm H and 1.
Below 2000 cnn, trip setting charcoal SGTS Flov - Train C R.H. Heater < 2000 cfm (A or F) heaters vill turn on.
Heaters 2.
Belov 2000 cfm, trip setting R.H.
heatern vill shut off.
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$1
g TABLE 3.2.5 (Continued)
Minimus No.
. Operable Per Trip Sys (1)
Function Trip I.evei Setting Action Remarks 4(4)
Instrument Channel -
_ 200*F.
A
- 1. Above trip setting initiates RCIC Steam Line Space High leakage alarm Teeperature 2(2)
Instrument Channel -
< 583" above vessel zero.
A
- 1. Above trip setting trips HPCI turbine.
Reactor Ilith Water Level 1
Instrument Channel -
_90 psi (7)
A
Flow 4(4)
Instrument Channel -
_ 200*F.
A
- 1. Above trip settin6 initiates HPCI Steam Line Space High leakage alarm Temperature 1
Core Spray System Logic N/A B
- 1. Includes testing auto initiation inhibit to Core Spray Systems in other units.
j 1
RCIC System (Initiating)
N/A B
- 1. Includes Groun 7 valves. Refer to Loe,1c Table 3.7.A for list of valves, i
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3.2 BASES and trips the recirculation, pumps. The low reactor water level instrumentation that j e, set to trip when reactor water level is 17.7" (378" above vessel zero) above the top of the active fuel (Table 3.2.8) initiates the LPCI, Core Sperg Pumps, contributes to ADS initiation and starts the diesel generatoIu. jdids&'crip eetting levels were chosen to be high enough to prevent spurious actuation but low enough to initiate CSCS operation so that post accident cooling can be accomplished and the guidelines of 10 CFR 100 will not be violated.
For large breaks up to the complete circumferential break of a 28-inch recirculation line and with the trip setting given above, CSCS initiation is initiated in time to meet the above criteria.
The high drywell pressure instrumentation is a diverse signal to the water level instrumentation and in addition to initiating CSCS, it causes isolation of Groups 2 and 8 isolation valves. For the breaks discussed above, this instrumentation will initiate CSCS operation at about the same time as the low water level instrumentation; thus the results given above are applicable here also.
Venturis are provided in the main steam lines as a means of measuring steam flow and also limiting the loss of mass inventory from the vessel during a steam line break accident. The primary function of the instrumentation is to detect a break in the main steam line. For the worst case accident, main steam line break outside drywell, a trip setting of 140% of rated steam flow in conjunction with the flow limiters and main steam line valve closure, limits the mass inventory loss such that fuel is not uncovered, fuel cladding g
temperatures remain below 1000 F and release of radioactivity to the environs is well below 10 CFR 100 guidelines.
Reference Section 14.6.5 FSAR.
Temperature monitoring instrumentation is provided in the main steam line tunnel to detect leaks in these areas. Trips are provided on this instrumentation and when exceeded, cause initiation of control room alarms.
The setting of 200 F for the main steam line tunnel detector is low enouogh to detect leaks of the order of 15 gpm; thus it is capable of covering the entire spectrum of breaks.
High radiation monitors in the main steam line tunnel have been provided to detect gross fuel failure as in the control rod drop accident. With the established setting of 6 times normal background, and main steam line isolation valve closure, fission product release is limited so that 10 CFR 100 guidelines are not exceeded for this accident.
Reference Section 14.6.2 FSAR. An alarm, with a nominal set point of 3 x normal full power background, is provided also.
Pressure instrumentation is provided to close the main steam isolation valves in Run Mode when the main steam line prescure drops below 825 psig.
112 9
}.2 BASFS_
and temperature instrumentattun are provided to detect The HPCI h1P.h flow a break in the HPCI steam piping. Tripping of high flow instinxmentation re-Tripping logic for the high sults in actuation of HPC1 isolation valves.
1 out of 2 logic and all sensors are required to be operable.
flow is a in the vicinity of the HPCI equipment is sensed by 4
. lligh temperature acts of 4 biectallic temperature switches.
The NPCI t rip settings of 90 psi f or high flow er.d 20C*T for high ter.-
i core uncovery is prevented and fission product perature are such that release la within 11=1ts.
instrumentation are arranged the samt The RCIC high flow and temperature as that for t.e HPCI. The trip setting of 450" H 0 for high flow and h
y 200*P f or tenperature are based on the same criteria as the HPC1.
the Reactor Cleanuo Syst,ee floor drain could indicate liigh tenperature at When high teopercture occurs, the cleanup a break in the cleanup system.
system is isolated.
The instrumentation which initiates CSCS action is arranced in a dual As f or other vits1 instrumentation stranged in this f ashion, bus system.
the ef f ectiveness of the systen cven during the Specification preserves An erecption to periods when maintenance or testing is being perforned.
this is when logic functional testina is being perforned.
The control rod block functions are provided to prevent excessive control rod withdrawal so that HCPR does not decrease to 1.07. The trip logic for this function is 1 out of n:
c.g., any t r ip on one of six APRM's, eight IRM's. or four SRM's will result in a rod block, t
instrumenta-The minimum instrument channel requirenents assure sufficient The minimum instru=ent tion to assuie the single failure criteria is cet.
channel requirements for the RSM may be reduced 'y one for maintenance, o
testing, or es11bration. This time period is only 3% of the operating time in a month and does not algnificantly increase the risk of preventing an inadvertent control rod withdrawal.
The APRM rod block function is flow biased and prevents a significant reduc-tion in HCPR, especially during operation at reduced flow. The APAN pro-vides gross core protection; i.e.
limits the gross core power increase The f rom withdrawal of control rods in the normal withcrawal sequence.
trips are set so that MCFR is maintained greater than 1.07.
The RBH tod bloca function provides local protection of the core; i.e.,
in a local region of the core, for a the prevention of critical power single rod withdrawal error from a limiting control rod pattern..
113 Amendment No. #, 47
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UNIT 3 PROPOSED CHANGES I
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TADLE 3.2.A s
PRIMm comArmm Arm aEen wxLoI:4c Isourton InstnerATIon Minimum No.
Instrument g
Channels Operabic e
g per Trip Sys(l) ru nct io, rrir Irvel set tin <r _
Action 111 Feiu r ks n
D 2
Instrument channel -
2 538= above vessel aero A or 1.
Below trip setting does the m
meactor low water revel (6)
(D and E) following:
a.
Initiates Peactor Duitsing V.
Isolation
.O b.
Init lates Frimary Containrer.t Isolation 1
ra c.
Initiates SCTS i
1 Instruzent Channel -
100 + 15 psig D
1.
Above trip setti+ 1 1solates the snutdown cooling su tson valves Peactor fligh Pressure of the EUR system.
2 Instrument channel -
) 2 970 above vessel sero A
1.
Below trip setting initiates ~.ain
~
i Steam Line Isolation peactor Iow water Ievel (LIS-3-56 A-D, SW 01) 2 Instrument Channel -
s 2.5 pses A or 1.
Above
- rip settir.9 soes the High crywell Pressure (6)
(D and E) following:
Initiates Peactor Bailding a.
(P S-6'6 - M A-D)
Isolation b.
Init lates IT.ta rf Containtient Isolation c.
Initi;.tes SGTS 2
Instrument Channel -
5 3 times normal rated 3
1.
Above trip setting initiates ruin Steam Line Isolation Bigh Radiation Main Steam f ull power lackgrocrat Line Tunnel (G) j 3
1.
Below trip setting initiates Main 2
Instrument channel -
Steam ttne Isolation Low Prescure Main Steam h825 psig (4)
Line i
2 (3)
Instru:nent Channel -
$ 1401 of rated steam ficw B.
1.
Above trip setting initiates Main Steam Lane Isolation
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Uigh Flow Main Steam Line 2 (10)
Instrument Channel -
s 2co*r B
1 Above trip setting initiates Main Stear Line- }cgkagg g } g g.m i
Main Steam Line Tunnel Righ Temperature 4
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l Table 3.2.8 INSTRUMENTATION TI!AT INITIATES OR CONTROLS T!!E CORE AND COVTAINMENT Ct>OLING SYSTIAS l'inimua No.
Operable Per nic_Sn_tJt runction Trip _rtvr1 ser e in, action Remarks 1
Core Spray Trip N/A C
1.
Mcnitors availability of power Systen bus to logic systems, power monitor 1
ADS Trip System bus N/A C
1.
Monitors availability of power pcwer monitor to logic systems and valves.
1 HirI Trip System bus IVA C
1.
Monitors availability of power gewer monitor to logic systems.
1 RCIC Trip System bus pouer II/A C
1.
!!cnitors availability of power monitor to logic systems.
1(2)
Instrument Channel -
2 Elev. 551' A
1.
Below trip setting will open Condancate Storage Tank Low HPCI suction valves to the Level (LS-73-56A & B) suppression chamber.
1(2)
Instrument Channel -
57" above normal water A
1.
Above trip settin; will open Suppression Chacher High level UPCI suction valves to the Level suppa m ion chamber.
S 2 (2)
Instrument Channel -
5 583" above vessel zero A
1.
Above trip setting trips RCIC Reactor High Water Level turbine.
1 Instrument Channel -
5 450" B 0 (7)
A 1.
Above trip setting isolates RCIC Turbine Steam Line RCIC system,and trips BCIC Uigh Flow turbine.
e 4 (t)
Instrument Channel -
$200*r.
A 1.
Above trip settin9 initiates RCIC Steam Line Space High Terperature leakage alarm t
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P Table 3.2.B INSTRUMENTATION TtiAT INITIATES OR CO*.TROLS THE CORE AND CONTAINMENT COOLIPM SYSTEMS Minimun No.
Operable Per Trip Sys ill Punct ion Trip Level set t ing Act ion Reharks 2 (2)
Instrument channel -
5583a above vessel zero.
A 1.
Atove trip setting trips HPCI turbine.
Reactor High Water Level 1
Instrument Channel -
5 90' psi (7)
A 1.
Above trip settini isolates HPCI system and trips HPCI turbine.
BPCI Turbine Steam Line Bigh Flow s te)
Instrument Channel -
s200*r.
A 1.
Above trip setting initiates BPCI Steam Line Space leakage alarm High Temperature 1
Core Spray System Logic N/A B
1.
Includes testing auto initiation inhibit to Core Spray Systems in other units.
1 RCIC System (Initiating)
N/A B
1.
Includes Group 7 valves.
Refer to Table 3.7.A for Logic list of valves.
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1 RCIC System (Isolation)
N/A B
1.
I'ncludes Group 5 valves.
Refer to Table 3.7.A for Logic list of valves.
1(16)
ADS Logic N/A A
(Initiation)
)
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r anl HPCI, and trips tne recirculation pumps.
The low reactor water level instrumentation that is set to trip when reactor water level is 17.7" (376" above vessel zero) above the top of the active fuel (Table 3. 2. E) initiates the LPCI, Core Spray Pumps, contributes to ADS initiation and starts the diesel generators.
These trip setting levels were chosen to be high enough to prevent spurious actuation but low enough to initiate CSCS operation so that post accident cooling can be accomplished and the guidelines of 10 CFR 100 will not te violated.
For large breaks up to the complete circumferential break of a 28-inch recirculation line and with the trip setting given above, CSCS initiation is initiated in time to meet the above criteria.
The high drywell pressure instrumentation is a diverse signal to the water level instrumentation and in addition to initiating CSCS, it causes isolation of Groups 2 and 8 isolation valves.
For the break; di scussed above, this instrumentation will initiate CSCS operation at about the same time as the low water level instrumentation; thus the results given above are applicalbe nere also.
Venturis are provided in the main steam lines as a means of measuring steam flow and also limiting the loss of mass inventory f rom the vess el during a steam line break accident.
The primary function of the instrumentatica is to detect a break in the main steam line.
For the worst case accident, main stean line break outside the drywell, a trip setting of 140% of rated steam flow in conjunction with the flow limiters and main steam line valve closure, limits the mass inventory loss such that fuel is not uncovered, fuel cladding temperatures remain below 10000F and release of radioactivity to the environs is well below 10 CFR 100 quidelines.
Reference Section 14.6.5 FSAR.
Temperature monitoring instrumentation is provided in the main steam line tunnel to detect leaks in these areas.
Trips are provided on this instrumentation and when exceeded, cause initiation of control room alarns.
The setting of 2000F for the main steam line tunnel detector is low enough to detect leaks of the order of 15 qpm; tnus, it is capable of covering the entire spectrum of breaks.
High radiation mcnitors in the main steam line tunnel have been provided to detect gross fuel failure as in the control rod drop l
accident.
With the established setting of 6 times normal background, and main steam line isolation valve closure, fission product release is limited so that 10 CFR 100 quidelines are not exceeded for this accident.
Reference Section 14. 6. 2 FSAR.
An l
a la rm, with a nominal set point of 3
x normal full power background, is provided also.
109
Pressure instrumentation is provided to close the main steam isolation valves in Run Mode when the main steam line pressure d ro p e, below E25 psig.
The IIPCI high flus and temperature instrumentation are provided to detect a break in the llPCI ste.im piping.
Tripping of the high flow in s t r umarat a t ion results in actuation of HPCI isolution valves.
Tri ppi nq logic for the high flow is a 1 out of 2 logic, and all sensor s are reguired to be operable.
High tei,perature in the vicinity of the HPCI equipment is sensed by 4 sets of 4 bimetallic temperature switches.
The HPCI trip settings of 90 psi for high flow and 2000F for high tenperature are such that core uncovery is prevented and fission product release is within li mit s.
The BCIC hiqh flow and temoerature instrumentation are arranged the same as th.st for the HPCI.
Tne trip betting cf 450" water for high flow and 2000F for temperature are based on the same criteria as the HFCI.
High temperature at the Reactor Cleanup System floor drain could indicate a break in the cleanup system.
When high temperature occurs, the cleanup system is isolated.
The instrumentation which initiates CSCS action is arranged in a dual bus system. As for other vital instrumentation arranged in this fashion, the Specification preserves the ef fectiveness of the system even during periods when naintenance or testing is being performed.
An exception to this is when logic functional testing i s being performed.
The control red block functions are provided to prevent excessive control rod withdrawal so t> at MCPR does not decrease to 1.07 Th3 trip logic for this f unction is 1 out of n:
e.g.,
any trip on one of six APRM's, eight IRM's, or four SRM's will result in a rod block.
The minimun instrument channel requirements assure sufficient instrumentation to assure the single failure criteria is met. Two h3M channels are provided and only one of these may be bypassed frem the console, for maintenance and/or testing provided that this condition does not last longer tl.an 2L hours in any thirty day pericd. This time period is only 3% of the operating tine in a racnth and does net significantly increase the risk of preventing an.
inadvertent control rod withdrawal. _
The APRM ro'i block function is flow biased and prevents a siqnificant reduct ion in MCPR, especially dur inq operation at reduced flow.
The Al'RM provides gross core protection; i.e.,
lini t s the gross core pnser incr eau f rom withdrawal of control 110
8 4
5 ENCLOSURE 2 JUSTIFICATION (TVA BFNP TS 144) 4
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Units 1 and 2, pages 56,157,112, and 113 Unit 3, pages 57, 69 (Intr. Channel - RCIC Steam Line Space High Temperature), 70, 109, and 110 Steam line space high temperature isolations are used to detect small line breaks. Breaks in these systems of sufficient size to endanger. fuel claddig integrity (small break LOCA size) are detected by both high flow and low pressure trips in the steam lines. The consequences of isolation from the steam line space high temperature lanction would cause nonconservative reactor water level fluctuations.
In the event of a steam space high temperature alarm on the HPCI, RCIC, or main steam system, the operator will be directed, through operating instructions, to verify the validity of the alarm by:
a.
Other instrumentation such as steam flows, pressure, and radiation monitors, or b.
Direct observation of the area involved.
In addition, other instrumentation is available which can provide isolation in the event of a steam line break. These incitde low reactor water level, high steam flow and low turbine steam pressure.
The high temperature alarms are both audio and visual. They are located in the main control room on a front annunciator panel.
Unit 3, page 69 (Instrument Channel - Suppression Chamber High Level)
Units 1 and 2 technical specification Tahle 3.2.B states that for the Suppression Chamber High Level function the mini =um number of operable instrument channels is one, while the unit 3 specification lists the minimum number as two.
This function is the same for all thrae units. The Browns Ferry FSAR, pages 7.4-8 and 7.4-9 indicates i
that only one channel is required to initiate the appropriate control action. This revision is needed to make the unit 3 technical specifications consistent with units 1 and ?.
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O ENCLOSURE 3 REFERENCE TO PREVIOUS CHANGES TO TECHNICAL SPECIFICATIONS (TVA BFNP TS 144)
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m Unit 1, page 56 and Unit 3, page 57 The change to the heading of the first column of Table 3 2.A and addition of the footnote (10) to the Main steam Line Tunnel High Temperature was proposed in requested change TVA BFNP TS 133 dated December 5, 1979 Unit 1, page 112 and Unit 2, page 109 The change to the trip and alarm setpoints for the main steam line tunnel high radiation monitors from 3.to 6 times and from 1.5 to 3 times background respectively, was proposed in requested change TVA BFNP TS 123 dated June 29, 1979, and supplement dated January 14, 1980.
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