ML20153D305
| ML20153D305 | |
| Person / Time | |
|---|---|
| Site: | Pilgrim |
| Issue date: | 08/23/1988 |
| From: | Thomas Koshy NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | |
| Shared Package | |
| ML20153D303 | List: |
| References | |
| 50-293-88-23, IEIN-86-003, IEIN-86-053, IEIN-86-3, IEIN-86-53, NUDOCS 8809020163 | |
| Download: ML20153D305 (15) | |
See also: IR 05000293/1988023
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U.S. NUCLEAR REGULATORY COMMISSION
REGION I
Report No.
50-293/88-23
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Cocket No.
50-293
License No. DPR-35
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Licensee: Boston Edison Company
800 Boylston Street
Boston. Massachusetts 02199
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Facility Name:
Pilgrim Nuclear Power Station. Unit 1
Inspection At:
Braintree and Plymouth. Massachusetts
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Inspection Cunducted: June 20-30, 1988
Inspectors:
b~O'N
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T. Koshy, Lead Reactor Engineer
date
$~/3 ~@8
fot J. F. Lara~ R ctor Engineer
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Approved by:
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C. J.VAnderson, Chief, Plant Systems Section
date
Inspection Summary: Thir. vas an announced inspection to review the licensee
corrective actions in response to Information Notice 86-03 regarding the
unqualified internal wiring in Limitorque valves and Informstion Notice
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No. 86-53 which addressed the improper installation of Raychem Heat Shrink
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tubing. This inspection also looked at some electrical open items.
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Results:
The licensee corrective action to address the qualifications of
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limitorque internal wiring was insufficient in that the inspectors observed
three unidentifiable wires in valves located inside the containment.
See
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Section 4 for details. The licensee developed additional test data for
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supporting the qualification of Raychem Heat Shrink Tubing installations.
Section 6 of this report documents the licensee response to previously
identified violations and unresolved items.
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The presence of unidentifiable wires in the environmentally qualified motor
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operated valves indicate a weakness in maintenance and quality control
activities.
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DETAILS
1.0 Persons Contacted
1.1 Boston Edison Company (BECo)
- M. Andrews, Sr. QC Engineer
J. Coughlin, Principal Electrical Engineer
S. Das, Sr. Electrical Engineer
S. Dasgupta, I&C Division Manager
N. Eisenmann, Sp. I&C Engineer
R. Fairbank, Design Section Manager
- F. Famular, QA Manager
D. W. Gerlits, Safety and Systems Analysis Engineer
"R. R. Grammont, Maintenance
- R. E. Grazio, Regulatory Affairs Section Manager
- P. Hamilton, Compliance Division Manager
- K.
L. Highfill, Station Director
E. J. Janus, Sr. Electrical Engineer, Nuclear Engineering Department
R. L. Kirven, Electrical Engineering Supervisor, Nuclear
Engineering Department
- F. J. Mogolesko, Environmental Qualification Proj et Manager
- A. V. Mori:1, Acting Planning and Outage Depa:tme t Manager
K. T. O'Donnell, Electrical Maintenance Engineer
J. Pawlak, Principal Electrical Engineer, Nuclear Engineering
Department
L. Perfetti, Electrical Engineer, Nuclear Engineering Department
- J. E. Peters, Electrical Division Manager
B. Rancourt, Sr. I&C Engineer
- J. A. Seery, Technical Section Manager
R. N. Swanson, Nuclear Engineering Manager
T. Tracy, Civil Structure Division Manager
- T. A. Venkataraman, Sr. QA Engineer
- R. Whetsel, Sr. Compliance Engineer
V. Zukauskas, Principal Structural Engineer
1.2
U.S. Nuclear Regulatory Commission (NRC)
T. J. Kim, Resident Inspector
J. J. Lyash, Resident Inspector
C. Warren, Senior Resident Inspector
- Present at the exit meeting on June 30, 1988.
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2.0 Purpose
The purpose of the inspection was to review the following items.
ihe environmental qualification of internal wiring utilized in the
Limitorque motor operated valves (MOVs) that are required to perform
safety functions in a harsh environment.
The installation of Raychem heat shrinkable tubing on safety related
cable splices.
Electrical and Equipment Qualification open items.
3.0 Background
On September 30, 1985 Commonwealth Edison reported to the NRC that it
discovered four Limitorque operators with jumper wires different from
those tested by Limitorque in their environmental qualification program.
Subsequent to this finding, several licensees identified similar problems.
That led to the issuance of Information Notice No. 86-03 which promulgated
the need for establishing the qualification of Limitorque internal wiring.
On May 14, 1986 the licensee for Davis Besse plant reported that termina-
tions and splices using heat shrinkable tubing were not done according to
the manufacturer's instructions in that the installed configuration placed
the plant in an unanalyzed condition.
Typical discrepancies included
improper diams'.cr of the tubing and, improper overlap of the heat shrink-
able tubing (HST). Discrepancies of this nature were observed at various
plants.
As a result NRC issued Information Notice No. 86-53,
4.0 Limitorque MOV Wiring (TI 2515/75)
The licensee inspected all MOVs covered under the EQ program to determine
if the internal wiring was environmentally qualified.
The licensee docu-
ment PDC 84-60 addressed the inspection and upgrade of the MOV wiring.
The inspectors reviewed the checklist and the work instructions contained
in the above docunent.
The document identified the acceptable wires and
also several other aspects of limitorque MOVs which are critical for main-
taining the equipment qualification.
The team selected the following
seven, from a total of seventy MOVs covered in the environmental qualifi-
cation (EQ) program.
The first two MOVs were selected from the valves
inside containment.
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MO-202-5A
MO-202-58
MO-1001-28A
MO-1001-43A
M0-1001-43C
M0-2301-10
MO-2301-33
All but two valves contained identifiable Rockbestos SIS or General Electric
Vulker.e Supreme wires.
Valves MO-202-5A and MO-202-5B contained wires
which could not be identified.
The inspectors noticed a red jumper wire
on the terminal block inside the Limitorque compartment of M0-202-5A.
It
was the only red wire and it did not have any identifiable markings on it.
The licensee presented a QC Verification Checklist dated November 2, 1984.
It refers to the following documents which trace the wire to be Gauge 12
E-928 Material Receiving Instruction dated June 7, 1934
82-027.1 Material Receiving Report for Purchase Order FN-4050Q
dated September 18, 1984
General Electric Certificate of Compliance dated February 14, 1985
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for Customer Order FN-4050Q
In MOV MO-202-5B the inspectors observed two types of unidentifiable wires
inside the Limitorque compartment. One was a grey wire with a red line
used as a jumper on the terminal block, the other was a white wire con-
nected between the limit switches.
The licensee presented the following
document to establish the origin of the wire.
84-060-04-E-002 QC Verification Checklist dated November 2,1984
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However, this document traced the wire to be a GE Vulkene Supreme red
wire.
The field installation was a grey wire with a red line on it.
This raised some questions regarding the adequacy of QC inspection.
The
licensee generated PCAQ NED 88-035 to address this concern.
The licensee
believes that the white wires on the limit switches were installed by the
manufacturer, Limitorque. The licensee initiated a 10 CFR Part 21 review
to address the extent of the problem and to evaluate this issue for
reportability to the NRC.
The licensee had replaced several MOV assemblies under PDC 84-16 in the
current plant outage. Only a few of those new assemblies were inspected
for Environmental Qualification requirements, as there were no discrepan-
cies identified in the first batch inspected.
In the light of the
concerns identified during this inspection, the licensee committed to
complete the walkdown of all new POVs for any potential EQ concerns,
before restart.
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Subsequent to the inspection, the licensee inspection revealed a few more
instances of unqualified wiring in MOVs. The licensee review concluded
that some of the wires are qua11fiable.
The presence of unidentifiable
wiring in the MOVs that are covered under the EQ program is an unresolved
item pending the licensee evaluation of the causes of the discrepancy and
the corrective action.
(50-293/88-23-01)
5.0 Raychem Heat Shrinkable Tubing Installation (TI2500/17)
In response to the NRC Information Notice 86-53, Improper Installation of
Heat Shrinkable Tubing, the licensee issued a "Potential Condition Adverse
to Quality Report." This report contained a preliminary evaluation that
recognized some concerns on the subject installations at Pilgrim Station.
PNPS conducted a field inspection of a sample of installations in order
to document the most limiting configurations to be addressed.
The sample
size chosen was equal to or greater than that specified in standard,
Sampling Procedures and Tables for Inspection By Attributes MIL-ST0-1050.
The selected samples were inspected to document acceptable configurations
that can be tested to establish qualification.
The test samples were then
made with a bend to crease and were subjected to equipment qualification
tests.
This test establishes qualification of Raychem splices with h"
real length for Gauge 14 and 16 cable sizes.
The other cable sizes were
tested with a one inch seal length.
Based on the licensee's acceptance criteria as supported by the qualifica-
tion data, the NRC inspectors reviewed the following selected installations.
Safety Related Penetration Q106B (approximately 20 power and control
splices)
MO-202-5A MOV
MO-1001-63 MOV
J208
Junction Box
J456
Standby Gas treatment splice box
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J177
Standby Gas treatment splice box
10-DPIS-261-12C Pressure Switch for Low Pressure Injection
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2-PS-1001-104A Pressure Switch
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2-PS-1001-93A Pressure Switch
The NRC inspectors walked down the above installations for the following
attributes.
Seal length of h inch to 1 inch per the licensee qualification data
Use of proper size HST
improper or inadequate shrinking of HST
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Use of HST over unqualified surfaces such as braided jackets
Appropriate use of shims
Based on the records verified and the samples inspected, no discrepancies
were observed.
The licensee has developed Procedure No. 3.M.3-17.1
"Field splice, Repair, and Sealing of Safety Related Cables (1000V and
Under) Raychem WCSF-N Sleeve NPK, NPKV, NMCK, NCBK and NESK kits
Installation".
The inspectors reviewed this procedure for the inclusion
of the manufacturer's requirements.
No violations or deviations were identified.
6.0 Status of Previcusly Identified Items
6.1 .(Update) Violation (88-08-01) Failure to Perform Periodic
Calibration / Testing of DC Circuit Breakers:
This violation pertains
to the failure of the licensee to perform periodic calibration / testing
of DC circuit breakers as required by PNPS Technical Specification
6.8A.
Periodic testing of these Class 1E breakers is specified to
ensure that they will perform their safety function when called upon.
The inspector reviewed BECo Nuclear Engineering Department's (NED)
analysis addressing the untested breakers.
The Pilgrim Unit 1 Report
88XE-1ER-Q, "Analysis of 125V and 250V DC System Molded Case Circuit
Breaker Maintenance and Testing" documented the analysis and methodology
used to develop a testing program for a representative sample of all
types of safety-related DC breakers installed at PNPS.
Testing
includes breakers of varying ratings and types.
A sample of 44 breakers
will be tested.
The inspector verified that all types of breakers
were considered for testing and reviewed NED's method of choosing the
sample to be tested.
The inspector reviewed in detail the technical analysis and basis
used to document the breaker testing program.
Independent
calculations revealed no discrepancies in the NED acceptance
criteria with respect to the guidelines presented in NEMA Standard
AB 2-1984, "Procedures for Field Inspection and Performance
Verification of Molded Case Circuit Breakers Used in Commercial and
Industrial Applications".
The breaker acceptance criteria was incorporated into PNPS procedure
8.Q.3-4, "125/250 VDC Motor Control Center Testing and Maintenance",
Revision 5.
The procedure provides maintenance personnel with
requirem...ts for periodic testing and maintenance of 125/250 VDC
Motor Control Centers.
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Upon conclusion of this inspection period, the licensee had completed
testing 23 of the 44 DC breakers.
The remaining breakers not yet
tested are being tracked and scheduled for completion prior to
restart.
Upon completion, NED will review the results to evaluate
breaker performance.
If all the breakers pass the acceptance
criteria, long-term testing will be scheduled for the entire popula-
tion of Class IE DC; breakers.
However, if any type of the breakers
fail the criteria, all breakers of that type in the entire population
will be tested before restart.
Test results and analyses will be provided to the NRC for review
prior to restart.
The licensee has committed to develop and
implement a long-term DC breaker surveillance testing program.
The
program will include the type and frequency of testing to be performed.
The licensee comnitted to implement this program by October 1,1988.
Pending NRC review of the test results, this issue will remain open.
6.2 (Closed) Violation (88-08-02) Inadequate Battery Maintenance: During
a previous special team inspection of the electrical power systems.
NRC inspectors identified examples of inadequate battery maintenance
and procedures.
Examples of corrosion by products were observed on
various battery terminals of the 125 VOC Control and 250 VDC power
batteries.
Licensee procedures did not include criteria for removal
of corrosion by products, spacing between battery cells and seismic
support racks, and verifying the torquing of battery connections.
The NRC inspector reviewed the licensee's response to the notice of
violation during this inspection.
The review revealed a revision of
the following procedures:
8.C.14, "Weekly Pilot Cell, Overall Battery Check and Battery
Charger Test", Revision 23
8.C.16, "Quarterly Battery Cell Surveillance", Revision 15
These procedures include battery surveillance criteria and
requirements of PNPS Technical Specification sections 4.9.A.2.a and
4.9.A.2.b.
These sections specify the weekly and quarterly battery
surveillance requirements.
Requirements for the inspection of corrosion by products on battery
terminals, battery cells and seismic support racks spacing, and
verification of proper terminal torque values are now incorporated
into a newly issued PNPS Plant Maintenance Procedure 3.M.3-25.1,
"Periodic Battery Inspections", Revision 0.
The inspectors inspected three battery banks for cleanliness and proper
maintenance.
Three separate cell terminals exibited varying degrees
cf corrosion on battery "B" (02).
Review of the licensee's Maintenance
Request (MR) log book indicated that several MRs were written to
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specifically clean the identified battery cell terminals which showed
sign of corrosion by-products.
Inade,uate cleaning and inspection
for the past several years has made all the battery terminals very
susceptive to corrosion. The inspector concluded that the issued MRs
provided only temporary and not long-term solution to the problem of
corrosion by products.
This lack of maintenance for all battery
cells could in the long run cause insufficient charging due to poor
terminal contact. The licensee agreed with the inspector that unless
all battery terminals and bolted connections were completely cleaned
and adequately maintained at the same time, corrosion by products
would be a recurring problem. The licensee committed to completely
clean and apply the protective wax on all battery banks prior to
restart.
Based on these actions, this violation is censidered closed.
6.3 (Closed) Unresolved * Item (88-03-05) Low Setpoints of Degraded Grid
Voltage Relays:
This item pertains to degraded grid voltage relay
setpoints being set too low to ensure minimum required voltages at
safety-related loads during a degraded grid scenario. On January 30,
1988 the licensee reported to the NRC that the degraded grid voltage
protection system setpoints were set too low.
The licensee committed
to complete a detailed review analysis of the Electrical Distribution
System to address low relay setpoints and recommend corrective
action.
BECo's Nuclear Engineering Department (NED) performed the review
analysis of the Electrical Distribution System.
NED's Power Systems
Group Study on load flow and voltage conditions of PNPS Auxiliary
Power Distribution System resulted in various modifications within
the electrical systems.
The study included new alarm and trip
setpoints for the degraded grid voltage protection system.
Based on
these setpoints, the minimum acceptable switchyard voltage had to be
revised.
In addition, to reduce voltage drops within the distribu-
tion system under LOCA conditions, certain loads will be shed from
the safety bus. To further assure proper voltage levels at loads,
RHR and CS pump starting logic will be modified to add a time delay
before any automatic start. Additional alarms will also be installed
to provide operators with additional information on the status of
load shed relays. Within the scope of,the study results, specific
non-safety loads will be relocated from safety busses to non-safety
busses.
Results of the NED study indicate that these modifications
will provide greater assurance that all safety-related equipment will
have adequate voltage for proper and safe operation during all modes
of operation.
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During this inspection period, the NRC inspectors held various
discussions with NED staff members. An in-depth review of NED's
voltage study was performed. Modifications resulting from the study
are documenied in PDC 88-07.
Results of the study, scope of
modifications, and inspector observations are described below.
A.
Degraded Grid Protection Setpoints for Alarm and Trip Relays:
PNPS is connected to the New England power grid through a 345
KV ring bus.
Rhode Island Eastern Massachusetts Vermont Energy
Control (REMVEC) monitors and assures that PNPS receives
adequtte power to be distributed throughout the station.
REMVEC presently has procedures in place to provide a minimum
of 330 KV at the PNPS switchyard.
Results of the group study
on load flow and voltage conditions revealed that the present
330 KV minimum required grid voltage would not ensure adequate
voltage for all safety-related loads under all operating
conditions.
Therefore, BECo has requested REMVEC to revise
their operating procedures to provide a minimum of 340 KV to
PNPS.
REMVEC will notify PNPS if the new minimum accaa+Qle
voltage cannot be maintained and thus allow PNPS to prepare for
necessary actions.
Based on the new minimum acceptable switchyard voltage,
modifications were made to the degraded voltage alarm and trip
relay setpoints.
New relays are being installed to support the
voltage range required by the new setpoints.
These new relays,
ITE-27N Undervoltage Relay, have higher accuracy and response
characteristics. Accordingly, trip relays now have a trip
setpoint of 3868V, as opposed to the previous setpoint of
3745V. Alarm relays are now set at 3959V, as opposed to the
previous setpoint 3850V.
These setpoints are applicable to
both Class IE 4.1GKV busses A5 and A6.
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The new trip setpoints correspond to an MCC voltage of 437V at
MCC busses B14 or BIS under worst case conditions.
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condition results in a margin of 7V above the minimum required
MCC voltage of 430V. However, it should be noted that the
worst case MCC voltage of 437V ocurrs at a switchyard voltage
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of 337KV which is below the minimum acceptable voltage of
340 KV. All other MCCs have a greater voltage margin.
The inspector reviewed BEco calculations PS-67 and PS-68 which
provide the analysis performed to determine the new trip and
alarm setpoints. No deficiencies were identified.
B.
Modification of Emergency Diesel Generator Lead Shedding logic:
This modification initiates load shedding under LOCA conditions
coincident with the safety related busses being supplied by the
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Startup Transformer. However, the load shedding logic will be
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initiated only if the 4.16KV bus voltage is at or below the
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alarm relay setpoint of 3959V for a duration greater than the
time delay of 9.2 seconds.
Loads to be stripped from the bus
are only those loads which are not required to mitigate the
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consequences of an accident. These load shedding logic changes
ensure that, when in any degraded voltage condition, sufficient
voltage is available to all safety-related loads.
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Other logic modifications include the removal of the Feedwater
Pump auxiliary oil pumps from the load shedding logic. These
pumps will not be stripped from the 4.16KV busses.
This will
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allow the plant operator to restart the pumps if needed.
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C.
Modification of RHR and CS Pump Starting Logic:
This modifica-
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tion ensures that, under LOCA conditions, adequate power is
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available for all required equipment and loads during load
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starting transients.
Pump starting logic for RHR and CS pumps
will be modified so that for any automatic pump start, time
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delays will be imposed when safety busses are being supplied by
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the startup transformer.
The time delay is the same that exists
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when the emergency diesel generator or the shutdown transformer
are supplying the Class 1E 4.16KV busses.
Specifically, CS
pumps will have a 1/3 second delay for any automatic start.
pumps A and B will have a 5 second delay while RHR pumps C and D
will have a 10 second delay for any automatic start.
D.
Additional load Shedding Alarms:
This modification provides
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the operator with additional alarms regarding the status of load
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shedding relays. Once a LOCA signal is received, alarms alert
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the operator that load shedding has been initiated.
Presently,
once the LOCA signal is cleared, these alarms are also cleared.
This situation can lead the operator to believe that all load
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shedding relays are reset and thereby loads can be restarted if
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needed.
However, there are some loads which require manual
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resetting of their respective load shedding relays.
This modi-
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fication provides for the installation of additional alarms to
alert the operator that certain loads are still shed and require
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manual resetting of their respective relays,
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Relocation of non-safety loads from safety-busses: This modift-
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cation, as documented in PDC 88-18, consists of relocating five
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non-safety loads from safety busses B14 and BIS to non-safety
busses B13 and B19B. The loads include plant heating pumps and
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auxiliary boilers and their associated equipment.
Relocating
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these loads reduces power requirements at the safety busses and
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thereby improves voltage during all modes of operation.
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NED analysis to determine relay setpoints was performed with the aid
of a commercial software program called Distribution Analysis for
Power Planning, Evaluations and Reporting (DAPPER).
Results of
NED's DAPPER generated calculations were cross-referenced with those
of Stone & Webster's similar main frame program.
Numerical
results were found to be essentially identical.
During this inspection, the NRC inspector performed an in-depth
review of various licensee documents pertaining to proposed degraded
grid protection system design changes. These documents were
reviewed independently and later discussed with NED staff members.
Documents reviewed are listed in Attachment 1.
New relay voltage
ranges and tolerances were reviewed to verify they supported the
voltage study requirements.
BECo is in the process of submitting proposed Technical Specification
changes to NRR for review and approval.
Technical Specification
changes incorporate the design modifications resulting from the load
analysis and voltage study.
Based on the information presented to the NRC inspector, this
unresolved item is considered closed.
6.4 { Closed) Unresolved Item (86-40-01) Raychem Splices on ECCS
Equipment:
This item pertains to the motor lead splices performed by
General Electric on 5 Kilovolts (KV) motor.
During January 1987 the
motor lead splices for these pumps were removed to facilitate 10 CFR 50 Appendix R, modifications.
During this removal, it was discovered
that B and D RHR pump motor splices were improperly installed, some
cable insulation damaged and some strands severed.
The licensee initiated an extensive program to reinspect the SKV
splices.
The problem was traced to a certain crew that performed the
splices. The licensee elected to replace the potentially affected
splices with a qualified splice using procedure No. 313 "5KV Cable
Splice Replacement" Revision 2.
The unqualified splices remained in
service only for a short duration when the plant was shutdown.
The
inspectors reviewed the following documents to verify the adequacy of
the corrective action.
Root cause and corrective action plan 86-192
Failure and Malfunction Report 86-435
Maintenance Request 86-10-53
The damaged cable was evaluated by General Electric Company and the
recommended corrective actions were taken by the licensee.
The
licensee has taken measures to increase QC attention on contractor
performed services.
This item is closed,
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6.5 (Closed) Unresolved item (50-293/88-08-04) Solid Fuse Links: This
item pertains to the use of solid links instead of fuses in the auto
trip circuit of the 4160 volt breakers and the Emergency diesel
generator field flashing circuits.
The licensee has elected to use solid links in the auto trip circuit
of the 4160 breaker to provide the maximum tripping capability.
This
circuit carries the current to operate the trip device only and does
not carry the fault current.
The trip signal from the protection
system is generated through remote sensing relays. Moreover, any
potential fault on this circuit will be interrupted by a magnetic
only circuit breaker.
The tripping of this breaker can cause power
failure only to one bus that belongs to one train.
The field flashing current is limited to approximately 60% of the no
load generator field current.
A 2.5 chm resistor limits this
current to approximately 50 amperes and is immediately removed when
the field is established.
Since this circuit is current limiting
and critical for field flashing, the fuse would function to provide
only short circuit protection.
For greater reliability in
establishing the field in the exciter, a solid link is used. The
use of a solid link provides an electrically continuous circuit to
function without interruption or failure. Short circuit protection
for the entire circuit is still provided by the circuit breaker at
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the distribution panel.
The consequences of tripping this circuit
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breaker, resulting from a short circuit, would be a loss of diesel
generator control power to an already inoperable generator due to a
failed field flashing circuit.
Since each diesel generator is
supplied from an electrically and physically independent DC power
supply, the tripping of the field flashing circuit breaker will not
affect the operability of the second diesel generator.
This item is closed.
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6.6 (Closed) Inspector Followup Item (87-53-05 Item #2)
Analog Trip System Fuses:
This item deals with the blown fuses in
the analog trip system during the loss of offsite power event on
November 12, 1987.
The licensee investigation discovered that four fuses were blown in
the analog trip system (ATI).
The failures were in the power supplies
of the ATI System. The root cause of the problem is attributed to
high inrush current due to repeated energizing and denergizing.
The
inspector reviewed the trip characteristics of the original fuse
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FNM KTKR, the fuse supplied by the manufacturer.
The licensee
replaced this fuse with an MIN type which is very similar to the
original fuse.
Due to the similarity in characteristics the
inspector, agreed with the licensee that the failure could have
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happened even with the use of the original fuse.
In order to prevent
similar fuse failures, BECo has installed a new type of fuse, FNM
which provides additional margin to accommodate switching transients.
The licensee review of other instrumentation fuses did not reveal any
new concerns.
This item is closed.
6.7 (Closed) Violation (87-32-0_1) Equipment Qualification Environmentg
P_rofile in Containment:
This pertains to the accident environment
profile utilized by the licensee for qualifying safety related equip-
ment located inside the drywell.
The qualification requirements for
this equipment is addressed in 10 CFR 50.49. As required by this
regulation, the licensee did not use the most limiting design basis
time dependent temperature profile to qualify the safety related
solenoid valve SV-220-44 and cable splice assemblies Q102A, Q102B,
Q103A and Q1038.
The licensee instead, qualified the equipment to a
large break temperature profile which was 30'F lower than the
temperature profile for a small break LOCA.
In response to this violation, the licensee developed a composite
imperature profile for the drywell environment.
This information
.as submitted to the NRC for review and is currently being reviewed
'y the office of the Nuclear Reactor Regulation.
The profile indicates
peak temperature of 320'F in the initial part of the accident.
The
s
licensee stated that all of the equipment was qualified based on the
documented test reports which the licensee had in possession before
November 30, 1985.
The inspectors reviewed the qualification basis of terminal blocks
used inside Limitorque compartments. The terminal blocks were
originally qualified as per test report No. B0119 which tested the
terminal blocks for a peak temperature of 311*F.
Limitorque test
report B-0027 dated August 31, 1978 provides data on the ambient
temperature of terminal blocks when the actuator is subjected to
high superheat conditions.
This test establishes that the internal
component temperature for terminal block does not exceed the saturated
steam temperature for the required operating duration.
Based on this
fact, the qualification of the terminal block is established through
test report B0119 for terminal blocks utilized in power and control
applications.
The inspectors also reviewed the licensee records on revising the
qualification data for other drywell instrumentation, cables, penetra-
tion and splices. No discrepancies were identified.
This item is closed.
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
'
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.'
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14
7.0 Unresolved Items
Unresolved items are matters for which more information is required in
order to ascertain whether they are acceptable, violations, or deviations.
One unresolved item is discussed in Section 4 of this report.
8.0 Exit. Interview
At the conclusion of the inspection on June 30, 1988, the inspectors
met with the licensee representatives denoted in Section 1.0.
The
inspectors summarized the scope and findings of the inspection at that
time.
No written material was provided to the licensee by the inspectors.
.
.
_ _ _ _
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ATTACHMENT 1
DOCUMENTS REVIEWE0
1)
Licensee Event report 88-003-000, "Low Setpoints of Degraded Grid Voltage
Relays due to Error in Model Used for Analysis," January 30, 1988.
2)
Failure and Malfunction Report 88-29, January 30, 1988.
3)
Plant Design Change (PDC) 88-10.
4)
Scope and Justificaticn Approval 88-10. "Replace Degraded Voltage Relays
and Modify Load Shedding Logic," February 4,1988.
5)
Field Revision Notice (FRN) 88-07-01.
6)
BEco Calculations:
a)
PS-67; Degraded voltage - trip setpoint, June 21, 1988
b)
PS-68; Degraded voltage - alarm setpoint, June 21, 1988
7)
Safety Evaluations:
a)
2277; Replacement of voltage relays and modification of load
shed logic
b)
2289; Technical Specification changes evaluation
c)
2290; Post FRN 88-07-01 evaluation.