Problems Associated with Testing, Tuning, or Resetting of Digital Control Systems While at PowerML031050587 |
Person / Time |
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Site: |
Beaver Valley, Millstone, Hatch, Monticello, Calvert Cliffs, Dresden, Davis Besse, Peach Bottom, Browns Ferry, Salem, Oconee, Mcguire, Nine Mile Point, Palisades, Palo Verde, Perry, Indian Point, Fermi, Kewaunee, Catawba, Harris, Wolf Creek, Saint Lucie, Point Beach, Oyster Creek, Watts Bar, Hope Creek, Grand Gulf, Cooper, Sequoyah, Byron, Pilgrim, Arkansas Nuclear, Three Mile Island, Braidwood, Susquehanna, Summer, Prairie Island, Columbia, Seabrook, Brunswick, Surry, Limerick, North Anna, Turkey Point, River Bend, Vermont Yankee, Crystal River, Haddam Neck, Ginna, Diablo Canyon, Callaway, Vogtle, Waterford, Duane Arnold, Farley, Robinson, Clinton, South Texas, San Onofre, Cook, Comanche Peak, Yankee Rowe, Maine Yankee, Quad Cities, Humboldt Bay, La Crosse, Big Rock Point, Rancho Seco, Zion, Midland, Bellefonte, Fort Calhoun, FitzPatrick, McGuire, LaSalle, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant |
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Issue date: |
10/22/1996 |
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From: |
Martin T Office of Nuclear Reactor Regulation |
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To: |
|
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References |
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IN-96-056, NUDOCS 9610160361 |
Download: ML031050587 (10) |
|
Similar Documents at Beaver Valley, Millstone, Hatch, Monticello, Calvert Cliffs, Dresden, Davis Besse, Peach Bottom, Browns Ferry, Salem, Oconee, Mcguire, Nine Mile Point, Palisades, Palo Verde, Perry, Indian Point, Fermi, Kewaunee, Catawba, Harris, Wolf Creek, Saint Lucie, Point Beach, Oyster Creek, Watts Bar, Hope Creek, Grand Gulf, Cooper, Sequoyah, Byron, Pilgrim, Arkansas Nuclear, Three Mile Island, Braidwood, Susquehanna, Summer, Prairie Island, Columbia, Seabrook, Brunswick, Surry, Limerick, North Anna, Turkey Point, River Bend, Vermont Yankee, Crystal River, Haddam Neck, Ginna, Diablo Canyon, Callaway, Vogtle, Waterford, Duane Arnold, Farley, Robinson, Clinton, South Texas, San Onofre, Cook, Comanche Peak, Yankee Rowe, Maine Yankee, Quad Cities, Humboldt Bay, La Crosse, Big Rock Point, Rancho Seco, Zion, Midland, Bellefonte, Fort Calhoun, FitzPatrick, McGuire, LaSalle, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant |
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Category:NRC Information Notice
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Mclaughlin on NRC, Regarding NRC Information Notice 2006-13: Groundwater Contamination 2020-09-03 The following query condition could not be considered due to this wiki's restrictions on query size or depth: <code> [[:Beaver Valley]] OR [[:Millstone]] OR [[:Hatch]] OR [[:Monticello]] OR [[:Calvert Cliffs]] OR [[:Dresden]] OR [[:Davis Besse]] OR [[:Peach Bottom]] OR [[:Browns Ferry]] OR [[:Salem]] OR [[:Oconee]] OR [[:Mcguire]] OR [[:Nine Mile Point]] OR [[:Palisades]] OR [[:Palo Verde]] OR [[:Perry]] OR [[:Indian Point]] OR [[:Fermi]] OR [[:Kewaunee]] OR [[:Catawba]] OR [[:Harris]] OR [[:Wolf Creek]] OR [[:Saint Lucie]] OR [[:Point Beach]] OR [[:Oyster Creek]] OR [[:Watts Bar]] OR [[:Hope Creek]] OR [[:Grand Gulf]] OR [[:Cooper]] OR [[:Sequoyah]] OR [[:Byron]] OR [[:Pilgrim]] OR [[:Arkansas Nuclear]] OR [[:Three Mile Island]] OR [[:Braidwood]] OR [[:Susquehanna]] OR [[:Summer]] OR [[:Prairie Island]] OR [[:Columbia]] OR [[:Seabrook]] OR [[:Brunswick]] OR [[:Surry]] OR [[:Limerick]] OR [[:North Anna]] OR [[:Turkey Point]] OR [[:River Bend]] OR [[:Vermont Yankee]] OR [[:Crystal River]] OR [[:Haddam Neck]] OR [[:Ginna]] OR [[:Diablo Canyon]] OR [[:Callaway]] OR [[:Vogtle]] OR [[:Waterford]] OR [[:Duane Arnold]] OR [[:Farley]] OR [[:Robinson]] OR [[:Clinton]] OR [[:South Texas]] OR [[:San Onofre]] OR [[:Cook]] OR [[:Comanche Peak]] OR [[:Yankee Rowe]] OR [[:Maine Yankee]] OR [[:Quad Cities]] OR [[:Humboldt Bay]] OR [[:La Crosse]] OR [[:Big Rock Point]] OR [[:Rancho Seco]] OR [[:Zion]] OR [[:Midland]] OR [[:Bellefonte]] OR [[:Fort Calhoun]] OR [[:FitzPatrick]] OR [[:McGuire]] OR [[:LaSalle]] OR [[:Fort Saint Vrain]] OR [[:Shoreham]] OR [[:Satsop]] OR [[:Trojan]] OR [[:Atlantic Nuclear Power Plant]] </code>.
[Table view]The following query condition could not be considered due to this wiki's restrictions on query size or depth: <code> [[:Beaver Valley]] OR [[:Millstone]] OR [[:Hatch]] OR [[:Monticello]] OR [[:Calvert Cliffs]] OR [[:Dresden]] OR [[:Davis Besse]] OR [[:Peach Bottom]] OR [[:Browns Ferry]] OR [[:Salem]] OR [[:Oconee]] OR [[:Mcguire]] OR [[:Nine Mile Point]] OR [[:Palisades]] OR [[:Palo Verde]] OR [[:Perry]] OR [[:Indian Point]] OR [[:Fermi]] OR [[:Kewaunee]] OR [[:Catawba]] OR [[:Harris]] OR [[:Wolf Creek]] OR [[:Saint Lucie]] OR [[:Point Beach]] OR [[:Oyster Creek]] OR [[:Watts Bar]] OR [[:Hope Creek]] OR [[:Grand Gulf]] OR [[:Cooper]] OR [[:Sequoyah]] OR [[:Byron]] OR [[:Pilgrim]] OR [[:Arkansas Nuclear]] OR [[:Three Mile Island]] OR [[:Braidwood]] OR [[:Susquehanna]] OR [[:Summer]] OR [[:Prairie Island]] OR [[:Columbia]] OR [[:Seabrook]] OR [[:Brunswick]] OR [[:Surry]] OR [[:Limerick]] OR [[:North Anna]] OR [[:Turkey Point]] OR [[:River Bend]] OR [[:Vermont Yankee]] OR [[:Crystal River]] OR [[:Haddam Neck]] OR [[:Ginna]] OR [[:Diablo Canyon]] OR [[:Callaway]] OR [[:Vogtle]] OR [[:Waterford]] OR [[:Duane Arnold]] OR [[:Farley]] OR [[:Robinson]] OR [[:Clinton]] OR [[:South Texas]] OR [[:San Onofre]] OR [[:Cook]] OR [[:Comanche Peak]] OR [[:Yankee Rowe]] OR [[:Maine Yankee]] OR [[:Quad Cities]] OR [[:Humboldt Bay]] OR [[:La Crosse]] OR [[:Big Rock Point]] OR [[:Rancho Seco]] OR [[:Zion]] OR [[:Midland]] OR [[:Bellefonte]] OR [[:Fort Calhoun]] OR [[:FitzPatrick]] OR [[:McGuire]] OR [[:LaSalle]] OR [[:Fort Saint Vrain]] OR [[:Shoreham]] OR [[:Satsop]] OR [[:Trojan]] OR [[:Atlantic Nuclear Power Plant]] </code>. |
vJ
UNITED STATES
NUCLEAR REGULATORY COMMISSION
OFFICE OF NUCLEAR REACTOR REGULATION
WASHINGTON, D.C. 20555-0001 October 22, 1996 NRC INFORMATION NOTICE 96-56: PROBLEMS ASSOCIATED WITH TESTING, TUNING,
OR RESETTING OF DIGITAL CONTROL SYSTEMS
WHILE AT POWER
Addressees
All holders of operating licenses or construction permits for nuclear power reactors.
Purpose
The U.S. Nuclear Regulatory Commission (NRC) is issuing this information notice to alert
addressees to recent reactor transient events, reactor trips, and engineered safety feature
actuations caused by testing, tuning, or resetting of digital control systems while at power. It
is expected that recipients will review the information for applicability to their facilities and
consider actions, as appropriate, to avoid similar problems. However, suggestions contained
in this information notice are not NRC requirements; therefore, no specific action or written
response is required.
Description of Circumstances
Washington Nuclear Project 2 (WNP-2)
On July 20, 1996, the WNP-2 facility experienced a rapid change in power of 15 percent in a
40-second timeframe. Specifically, power dropped from 68 to 53 percent and returned to
68 percent. The licensee determined that the power transient resulted from testing of the
recently installed digital adjustable speed drive modification to the reactor recirculation
pumps. The adjustable speed drive provides the capability to change the speed of the
reactor recirculation pump motors and eliminates the need for recirculation flow control
valves.
Before the event, the licensee was preparing to increase reactor recirculation flow from 51 to
53 percent. As part of the preparation, a nonlicensed General Electric (GE) test engineer
typed computer instructions that would return the reactor recirculation flow to 51 percent if
electrical harmonics were experienced in the adjustable speed drive system during the
reactor recirculation flow increase. Once these instructions were typed, a licensed reactor
operator would verify the entry and only had to strike the "ENTER" key on the computer
keyboard to execute the instruction. It was intended that the licensed operator would only hit
the ENTER key and execute the instruction if the system started to experience electrical
harmonics as reactor recirculation flow was increased. If there were no electrical harmonics, W
the instruction would not be executed. In this instance, the GE engineer typed an incorrect
R N I C9610160361 PDR ran- NOTICEq&"'OS6S 1&1022- gas~L
i
IN 96-56 October 22, 1996 value (transposed numbers) and then mistakenly executed the instruction by striking the
ENTER key. These actions caused reactor recirculation flow and reactor power to drop.
Immediately after entering the data, the GE engineer recognized the error and corrected the
instruction, thereby increasing reactor power. This event is discussed in NRC Inspection
Report 50-397/96-16 dated September 12, 1996 (Accession No. 9609190275).
Dresden Unit 2 On May 31, 1996, while at approximately 45-percent power, Dresden Unit 2 experienced a
loss of reactor feedwater control and a subsequent decrease in reactor vessel water level
while performing an on-ine configuration change to the recently installed Bailey Network 90
digital feedwater control system. Operators initiated a manual reactor scram as a result of
the decrease in the reactor vessel water level.
Before the event, the licensee was performing startup testing of the Bailey Network 90
feedwater control system modification. During the startup testing, the test team determined
that a minor software logic change was required to correct a problem associated with
automatic transition from the 2B feedwater regulating valve to the 2A valve. An original
equipment manufacturer representative indicated that the proposed software logic change
could be completed with the control system on-line. The manufacturer representative
indicated that the system would check the logic before going into the control mode and, as a
result, there would be no impact on plant operation. The test team reviewed and approved
the on-ine logic change; however, the approval process was not documented per station
procedure.
The new software logic configuration was inserted on the backup control module. Automatic
diagnostic checks indicated a successful load into the control module. Upon placing the
backup control module in the execute mode, the 2B feedwater regulating valve began to
close, resulting in a sudden drop in feedwater flow and reactor vessel water level.
During a subsequent design review of the Bailey Network 90 feedwater control system, a
logic execution sequence error was found in the original logic design of the Bailey
Network 90 firmware. This error caused the 2B feedwater regulating valve to dose when the
backup control module attempted to take over process control from the primary module. It
was determined that the execution sequence error would have resulted in the same process
control failure any time the backup control module attempted to take control from the primary
control module with the control system in the automatic mode. This event is discussed in
NRC Inspection Report 50-237/96-06 dated August 22, 1996 (Accession No. 9609030142).
Browns Ferry Unit 2 On May 10, 1996, Browns Ferry Unit 2 experienced an automatic reactor scram on low
reactor water level from full power. The low water level resulted from an unexpected runback
of two of the three reactor feedwater pumps, which occurred while software parameter
changes were being made in the recently installed digital feedwater control system.
Specifically, the flow biasing of the feedwater pumps was being adjusted and the control
system speed demand limit was being increased while at power in an effort to fine tune the
IN 96-56 October 22, 1996 system and thereby enhance system performance. When the software parameter changes
were made active (saved) in the control system, a reinitialization sequence occurred within
the control software block, which drove the feed pump speed demand signal to zero for a few
seconds. Plant personnel were unaware that entering these new software parameters would
cause the feedwater control system to reinitialize.
The cause of the event was attributed to inadequate design of the control system software.
The digital feedwater control system is a Foxboro I/A distributed control system. The system
software contains 380 software blocks, that is, logic functions performed by the computer. A
design weakness existed in the installed system in that making software parameter changes
in certain software blocks would cause the control system to automatically reinitialize to zero
output. During its investigation, the licensee confirmed that for 5 of the 380 software blocks, a parameter change would result in a control system reinitialization. This characteristic of the
software design was not known to the plant personnel. As part of its corrective actions, the
licensee modified the five affected software blocks to eliminate the reinitialization problem.
This event is discussed in NRC Inspection Report 50-260196-05 dated June 19, 1996 (Accession No. 9607030386).
Comanche Peak Unit 2 On May 5, 1996, while in Mode 3, Comanche Peak Unit 2 experienced an auto-start of the
motor-driven auxiliary feedwater pumps while personnel were resetting the central processing
units in the digital main feedwater pump turbine control system. Before the event, the vendor
representative for the newly installed main feedwater pump control system requested access
to reset the central processing units following completion of system testing. The shift
manager cautioned the vendor and nonlicensed utility instrumentation and controls personnel
that two of the three processors were required to be in service to avoid a trip of the main
feedwater pumps.
The instrumentation and controls personnel and the vendor representative planned to reset
the three central processing units one at a time to avoid initiating a trip of the main feedwater
pumps. The first two processors were rebooted. However, during the reset of the third
processor, an inadvertent trip signal was generated for both main feedwater pumps. This
signal caused an auto-start of the motor-driven auxiliary feedwater pumps (an engineered
safety feature actuation). All four motor-driven auxiliary feedwater flow control valves shifted
to auto and opened. Both motor-driven auxiliary feedwater pumps were operating and
supplying the required flow to the steam generators before the event.
The licensee concluded that the personnel performing the rebooting task did not adequately
verify that the second processor was properly restored and functional before rebooting the
third processor. The main feedwater pump trip signal was generated because the system
sensed that two of the three central processing units were not functional.
Discussion
In recent years, many licensees have chosen to replace outdated analog control systems with
digital upgrades. Digital system retrofits are intended to improve system performance,
K)
IN 96-56 October 22, 1996 reliability, flexibility, and operator interface characteristics. These systems also offer the
capability to change software parameters, setpoints, or logic configurations or to reset
processors while at power. However, as illustrated in the events previously described, resetting processors in digital control systems or performing on-line software manipulations
as part of digital control system tuning or testing can result in unforeseen transients, reactor
trips, and engineered safety feature actuations.
The events described herein highlight the importance of evaluating proposed changes and
developing and implementing controls for performing any type of on-line manipulation of
digital control systems to avoid reactor transients and plant trips. When it is deemed
necessary to reset a processor or to perform on-line software changes, it is important to
maintain control of these activities in order to minimize potential errors, and to be aware of
the potential effect on plant operation if errors occur while performing such activities.
This information notice requires no specific action or written response. If you have any
questions about the information in this notice, please contact one of the technical contacts
listed below or the appropriate Office of Nuclear Reactor Regulation (NRR) project manager.
Ia Thomas T. Martin, Director
Division of Reactor Program Management
Office of Nuclear Reactor Regulation
Technical contacts: Charles Petrone, NRR Jerry L. Mauck, NRR
(301) 415-1027 (301) 415-3248 Email: odp@nrc.gov Email: jlm2@nrc.gov
John K. Ganiere, NRR
(301) 415-2921 Email: jkg@nrc.gov
Attachment: List of Recently Issued NRC Information Notices
V N o >
K>
Attachment
IN 96-56 October 22, 1996 LIST OF RECENTLY ISSUED
NRC INFORMATION NOTICES
Information Date of
Notice No. Subject Issuance Issued to
96-55 Inadequate Net Positive 10/22/96 All holders of OLs or
Suction Head of Emergency CPs for nuclear power
Core Cooling and Contain- reactors
ment Heat Removal Pumps
Under Design Basis Accident
Conditions
96-54 Vulnerability of Stainless 10/17/96 All materials licensees
Steel to Corrosion When
Sensitized
96-53 Retrofit to Amersham 660 10/15/96 All industrial radio- Posilock Radiography graphy licensees
Camera to Correct Incon- sistency in 10 CFR Part 34 Compatibility
95-04, Excessive Cooldown 10/11/96 All holders of OLs or CPs
Supp. 1 and Depressurization and vendors for nuclear
of the Reactor Coolant power reactors
System Following Loss
of Offsite Power
96-40, Deficiencies in 10/07/96 All holders of OLs or CPs
Supp. 1 Material Dedication for nuclear power reactors
and Procurement
Practices and in
Audits of Vendors
96-52 Cracked Insertion 09/26/96 All U.S. Nuclear Regulatory
Rods on Troxler Commission portable gauge
Model 3400 Series licensees and vendors
Portable Moisture
Density Gauges
OL = Operating License
CP = Construction Permit
IN 96-56 October22, 1996 reliability, flexibility, and operator interface characteristics. These systems also offer the
capability to change software parameters, setpoints, or logic configurations or to reset
processors while at power. However, as illustrated in the events previously described, resetting processors in digital control systems or performing on-ine software manipulations
as part of digital control system tuning or testing can result in unforeseen transients, reactor
trips, and engineered safety feature actuations.
The events described herein highlight the importance of evaluating proposed changes and
developing and implementing controls for performing any type of on-line manipulation of
digital control systems to avoid reactor transients and plant trips. When it is deemed
necessary to reset a processor or to perform on-line software changes, it is important to
maintain control of these activities in order to minimize potential errors, and to be aware of
the potential effect on plant operation if errors occur while performing such activities.
This information notice requires no specific action or written response. If you have any
questions about the information in this notice, please contact one of the technical contacts
listed below or the appropriate Office of Nuclear Reactor Regulation (NRR) project manager.
original signed by D.B. Matthews
Thomas T. Martin, Director
Division of Reactor Program Management
Office of Nuclear Reactor Regulation
Technical contacts: Charles Petrone, NRR Jerry L. Mauck, NRR
(301) 415-1027 (301) 415-3248 Email: cdp@nrc.gov Email: jIm2@nrc.gov
John K. Ganiere, NRR
(301) 415-2921 Email: jkg@nrc.gov
Attachment: List of Recently Issued NRC Information Notices
Tech Editor reviewed and concurred on 8/21/96
- SEE PREVIOUS CONCURRENCES DOCUMENT NAME: 96-56.IN
To receive a copy of this document, indicate hIthe box: 'C - Copy w/o
attachment/enclosure 'E- - Copy w/attachment/enclosure *N - No copy ^See previous concurrence
OFFICE TECH CONTS E C:PECB:DRPM D:_DRPM
NAME JGaniere* AChaffee* TMarti
JMauck* J
CPetrone*
Date 10/15/96 10/ /96 7_/96
10/
OFFICIAL RECORD COPY
IN 96-xx
October xx, 1996 Discussion
In recent years, many licensees have chosen to replace outdated analog control systems with
digital upgrades. Digital system retrofits are intended to improve system performance, reliability, flexibility, and operator interface characteristics. These systems also offer the
capability to change software parameters, setpoints, or logic configurations or to reset
processors while at power. However, as illustrated in the events previously described, resetting processors in digital control systems or performing online software manipulations
as part of digital control system tuning or testing can result in unforeseen transients, reactor
trips, and engineered safety feature actuations.
The events described herein highlight the importance of evaluating proposed changes and
developing and implementing controls for performing any type of on-line manipulation of
digital control systems to avoid reactor transients and plant trips. When it is deemed
necessary to reset a processor or to perform on-line software changes, it is important to
maintain control of these activities in order to minimize potential errors, and to be aware of
the potential effect on plant operation if errors occur while performing such activities.
This information notice requires no specific action or written response. If you have any
questions about the information in this notice, please contact one of the technical contacts
listed below or the appropriate Office of Nuclear Reactor Regulation (NRR) project manager.
Thomas T. Martin, Director
Division of Reactor Program Management
Office of Nuclear Reactor Regulation
Technical contacts: Charles Petrone, NRR Jerry L. Mauck, NRR
(301) 415-1027 (301) 415-3248 Email: cdp@nrc.gov Email: jIm2@nrc.gov
John K. Ganiere, NRR
(301) 415-2921 Email: jkg@nrc.gov
Attachment: List of Recently Issued NRC Information Notices
- SEE PREVIOUS CONCURRENCES
DOCUMENT NAME: IN-XX.DIG
To receive a copy of this document. hIdicate In the box: IC' - Copy w/o
IF' - rnn, w/attanhmantlandnisura JN'- No cOrv *Seearevious concurrence
OFFICE TECH CONTS IE C:PECB:DRPM D:DRPM I
NAME JGanie AChaffee* TMartin
JMauck
CPetrone >bW
DATE 10/15/96 X 8 /29/96 / /96 OFFICIAL RECORI) COPYa
44A
- <~2 IN 96-xx
September xx, 1996 power. However, as illustrated in the events previously described, resetting
processors in digital control systems or performing on-line software
manipulations as part of digital control system tuning or testing can result
in unforeseen transients, reactor trips, and engineered safety feature
actuations.
The events described herein highlight the importance of developing and
implementing controls for performing any type of on-line manipulation of
digital control systems to avoid reactor transients and plant trips. When it
is deemed necessary to reset a processor or to perform on-line software
changes, it is important to maintain control of these activities in order to
minimize potential errors, and to be aware of the potential effect on plant
operation if errors occur while performing such activities.
This information notice requires no specific action or written response. If
you have any questions about the information in this notice, please contact
one of the technical contacts listed below or the appropriate Office of
Nuclear Reactor Regulation (NRR) project manager.
Thomas T. Martin, Director
Division of Reactor Program Management
Office of Nuclear Reactor Regulation
Technical contacts: Charles Petrone, NRR
(301) 415-1027 Email: cdp~nrc.gov
John K. Ganiere, NRR
(301) 415-2921 Email: jkg~nrc.gov
Jerry L. Mauck, NRR
(301) 415-3248 Email: Jlm2@nrc.gov
Attachment: List of Recently Issued NRC Information Notices
DOCUMENT NAME:
To receive a copy of ths document. Idlcate Inthe box: 'e
attachment/enclosure 'E' - Copy wlattachmentlenclosure 'N' - No copy *See previous concurrence -
OFFICE TECH CONTS IE C:PECB:DRPM I D:DRPM 1 Z I I
NAME JGanier AChaffee* TMartin
JMauclc
CPetrone _ _ _ _
DATE 8 /29/96 / /96 OFFICIAL RECORD COPY
IN 96-xx
August xx, 1996 The events described herein highlight the importance of developing and
implementing controls for performing any type of on-line manipulation of
digital control systems to avoid reactor transients and plant trips. When it
is deemed necessary to reset a processor or to perform on-line software
changes, It is important to maintain control of these activities in order to
minimize potential errors, and to be aware of the potential effect on plant
operation if errors occur while performing such activities.
This information notice requires no specific action or written response. If
you have any questions about the information in this notice, please contact
one of the technical contacts listed below or the appropriate Office of
Nuclear Reactor Regulation (NRR) project manager.
Thomas T. Martin, Director
Division of Reactor Program Management
Office of Nuclear Reactor Regulation
Technical contacts: Charles Petrone, NRR
(301) 415-1027 Email: cdp~nrc.gov
John K. Ganiere, NRR
(301) 415-2921 Email: jkg@nrc.gov
Jerry L. Mauck, NRR
(301) 415-3248 Email: jlm2@nrc.gov
Attachment: List of Recently Issued NRC Information Notices
my, s,£6 ASMc
&."8 sAid
- See previous concurrence dockw.' t~aunta
DOCUMENT NAME:
To aceive a copy f tes docunmkt Incate hi the box: C - COpy vcony
t.C .,I .. ,4,,.t n
If - _nv WV/ttanhmantlare mastrt
O UA ' No dODV
OFFICE TECH CONTS E C:PECB:DRPM D:DRPM I I
NAME JGaniere* AChaffee TMartin
JMauck*
CPetrone*
DATE 08/26/96 V/1o96 / /96
08/26/96 _
08/26/96 C O
l OF:FICIAL RECORD COP
'-> IN 96- August , 1996 The events described herein highlight the importance of developing and
implementing controls for performing any type of on-line manipulation of
digital control systems to avoid reactor transients and plant trips. When it
is deemed necessary to reset a processor or to perform on-line software
changes, it is important to maintain control of these activities in order to
minimize potential errors, and to be aware of the potential effect on plant
operation if errors occur while performing such activities.
This information notice requires no specific action or written response. If
you have any questions about the information in this notice, please contact
one of the technical contacts listed below or the appropriate Office of
Nuclear Reactor Regulation (NRR) project manager.
Thomas T. Martin, Director
Division of Reactor Program Management
Office of Nuclear Reactor Regulation
Technical contacts: Charles Petrone, NRR
(301) 415-1027 Email: cdp@nrc.gov
John K. Ganiere, NRR
(301) 415-2921 Email: jkg@nrc.gov
Jerry L. Mauck, NRR
(301) 415-3248 Email: jlm2@nrc.gov
Attachment: List of Recently Issued NRC Information Notices
DOCUMENT NAME:
To receive a copy of this document, Indlcate In the box: 'C' - Copy w/o
attachmentlenclosure 'E' - Copy wlattachmentlenclosure CNU- No copy
OFFICE TECH CONTS C:PECB:DRPM _ID:DRPMIIIIIIIII
NAME JGa AChaffee TMartin
JMa
DATE
CPetr
8 hi/ 6 e_ / /96 / /96 R/Cv/96 Ak6S/96 OFFICIAL RECORD COPY
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list | - Information Notice 1996-01, Potential For High Post-Accident Closed-Cycle Cooling Water Temperatures to Disable Equipment Important to Safety (3 January 1996)
- Information Notice 1996-01, Potential for High Post-Accident Closed-Cycle Cooling Water Temperatures to Disable Equipment Important to Safety (3 January 1996)
- Information Notice 1996-02, Inoperability of Power-Operated Relief Valves Masked by Downstream Indications During Testing (5 January 1996, Topic: Stroke time)
- Information Notice 1996-03, Main Steam Safety Valve Setpoint Variation as a Result of Thermal Effects (5 January 1996)
- Information Notice 1996-03, Main Steam Safety Valve Setpoint Variation As a Result of Thermal Effects (5 January 1996)
- Information Notice 1996-04, Incident Reporting Requirements for Radiography Licensees (10 January 1996, Topic: Brachytherapy)
- Information Notice 1996-05, Partial Bypass of Shutdown Cooling Flow from Reactor Vessel (18 January 1996, Topic: Reactor Vessel Water Level)
- Information Notice 1996-06, Design & Testing Deficiencies of Tornado Dampers at Nuclear Power Plants (25 January 1996)
- Information Notice 1996-07, Slow Five Percent Scram Insertion Times Caused by Viton Diaphragms in Scram Solenoid Pilot Valves (26 January 1996)
- Information Notice 1996-08, Thermally Induced Pressure Locking of a High Pressure Coolant Injection Gate Valve (5 February 1996, Topic: Anchor Darling, Cold shutdown justification)
- Information Notice 1996-09, Damage in Foreign Steam Generator Internals (12 February 1996, Topic: Earthquake)
- Information Notice 1996-10, Potential Blockage by Debris of Safety System Piping Which Is Not Used During Normal Operation or Tested During Surveillances (13 February 1996)
- Information Notice 1996-10, Potential Blockage by Debris of Safety System Piping Which is Not Used During Normal Operation or Tested During Surveillances (13 February 1996)
- Information Notice 1996-11, Ingress of Demineralizer Resins Increases Potential For Stress Corrosion Cracking of Control Rod Drive Mechanism Penetrations (14 February 1996)
- Information Notice 1996-11, Ingress of Demineralizer Resins Increases Potential for Stress Corrosion Cracking of Control Rod Drive Mechanism Penetrations (14 February 1996)
- Information Notice 1996-12, Control Rod Insertion Problems (15 February 1996)
- Information Notice 1996-13, Potential Containment Leak Paths Through Hydrogen Analysis (26 February 1996)
- Information Notice 1996-14, Degradation of Radwaste Facility Equipment at Millstone Nuclear Power Station, Unit 1 (1 March 1996)
- Information Notice 1996-15, Unexpected Plant Performance During Performance of New Surveillance (8 March 1996)
- Information Notice 1996-16, BWR Operation with Indicated Flow Less than Natural Circulation (14 March 1996)
- Information Notice 1996-17, Reactor Operation Inconsistent with the Updated Final Safety Analysis Report (18 March 1996)
- Information Notice 1996-18, Compliance with 10 CFR Part 20 for Airborne Thorium (25 March 1996, Topic: Brachytherapy)
- Information Notice 1996-19, Failure of Tone Alert Radios to Activate When Receiving a Shortened Activation Signal (2 April 1996)
- Information Notice 1996-20, Demonstration of Associated Equipment Compliance with 10 CFR 34.20 (4 April 1996, Topic: Brachytherapy)
- Information Notice 1996-21, Safety Concerns Related to the Design of the Door Interlock Circuit on Nucletron High-Dose Rate and Pulsed Dose Rate Remote Afterloading Brachytherapy Devices (10 April 1996, Topic: Brachytherapy)
- Information Notice 1996-22, Improper Equipment Settings Due to Use of Nontemperature-Compensated Test Equipment (11 April 1996, Topic: Brachytherapy)
- Information Notice 1996-23, Fires in Emergency Diesel Generator Exciters During Operation Following Undetected Fuse Blowing (22 April 1996, Topic: Brachytherapy)
- Information Notice 1996-24, Preconditioning of Molded-Case Circuit Breakers Before Surveillance Testing (25 April 1996, Topic: Brachytherapy)
- Information Notice 1996-25, Traversing In-Core Probe Overwithdrawn at Lasalle County Station, Unit 1 (30 April 1996, Topic: Brachytherapy)
- Information Notice 1996-26, Recent Problems with Overhead Cranes (30 April 1996, Topic: Brachytherapy)
- Information Notice 1996-26, Recent Problems With Overhead Cranes (30 April 1996)
- Information Notice 1996-27, Potential Clogging of High Pressure Safety Injection Throttle Valves During Recirculation (1 May 1996, Topic: Brachytherapy)
- Information Notice 1996-28, Suggested Guidance Relating to Development and Implementation of Corrective Action (1 May 1996, Topic: Brachytherapy)
- Information Notice 1996-29, Requirements in 10 CFR Part 21 for Reporting and Evaluating Software Errors (20 May 1996, Topic: Brachytherapy)
- Information Notice 1996-30, Inaccuracy of Diagnostic Equipment for Motor-Operated Butterfly Valves (21 May 1996)
- Information Notice 1996-31, Cross-Tied Safety Injection Accumulators (22 May 1996)
- Information Notice 1996-32, Implementation of 10 CFR 50.55a(g) (6) (II) (A), Augmented Examination of Reactor Vessel (5 June 1996, Topic: Non-Destructive Examination)
- Information Notice 1996-32, Implementation of 10 CFR 50.55a(g) (6) (ii) (A), Augmented Examination of Reactor Vessel (5 June 1996, Topic: Nondestructive Examination)
- Information Notice 1996-33, Erroneous Data From Defective Thermocouple Results in a Fire (24 May 1996, Topic: Reverse polarity)
- Information Notice 1996-33, Erroneous Data from Defective Thermocouple Results in a Fire (24 May 1996, Topic: Reverse polarity)
- Information Notice 1996-34, Hydrogen Gas Ignition During Closure Welding of a VSC-24 Multi-Assembly Sealed Basket (31 May 1996)
- Information Notice 1996-35, Failure of Safety Systems on Self-Shielded Irradiators Because of Inadequate Maintenance and Training (11 June 1996)
- Information Notice 1996-36, Degradation of Cooling Water Systems Due to Icing (12 June 1996, Topic: High winds, Ultimate heat sink, Frazil ice)
- Information Notice 1996-37, Inaccurate Reactor Water Level Indication and Inadvertent Draindown During Shutdown (18 June 1996, Topic: Reactor Vessel Water Level)
- Information Notice 1996-38, Results of Steam Generator Tube Examinations (21 June 1996)
- Information Notice 1996-39, Estimates of Decay Heat Using ANS 5.1 Decay Heat Standard May Vary Significantly (5 July 1996)
- Information Notice 1996-40, Defciencies in Material Dedication and Procurement Practices and in Audits of Vendors (7 October 1996, Topic: Coatings, Troxler Moisture Density Gauge)
- Information Notice 1996-41, Effects of a Decrease in Feedwater Temperature on Nuclear Instrumentation (26 July 1996)
- Information Notice 1996-42, Unexpected Opening of Multiple Safety Relief Valves (5 August 1996, Topic: Reactor Vessel Water Level)
- Information Notice 1996-43, Failures of General Electric Magne-Blast Circuit Breakers (2 August 1996)
... further results |
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