United States Nuclear Regulatory Commission - Protecting People and the Environment


ACCESSION #: 9511150379



                        ROOT CAUSE EVALUATION OF

                          4KV BREAKER SECONDARY

                          CONTACT BLOCK FAILURE

                               RCE 95-010



                              ATTACHMENT #1



                        ROOT CAUSE EVALUATION OF

                          4KV BREAKER SECONDARY

                          CONTACT BLOCK FAILURE

                               RCE 95-010



                             AUGUST 11, 1995



AUTHORED BY:

                    J. B. Riddle

                    Root Cause Engineer



                    M.S. Mostafa, PhD

                    Sr, Root Cause Engineer



REVIEWED BY:

                    W. W. Strom, Supervisor

                    Independent Safety Engineering



APPROVED BY:

                    A. J. Schramm, Manager

                    Safety Engineering



                        CLARIFICATION OF PURPOSE



This report is intended to be a self-critical use of hindsight to

identify all problems and the sources of those problems.  The root causes

identified in this report were discovered and analyzed using all

information and results available at the time it was written.  All such

information was, of course, not available during the timeframe in which

relevant actions were taken and decisions were made.



The purpose of using such a self-critical approach is to provide the most

comprehensive analysis possible for identifying "lessons learned" as a

basis for improving future performance.  The use of an open, documented

self-critical analysis program is imperative in the nuclear power

industry and cannot be compromised or confused with a management prudency

assessment.



Thus, this report does not attempt to make a balanced judgement of the

prudency or reasonableness of any of the actions or decisions that were

taken by vendors, utility management, or individual personnel based on

the information that was known or available to them at the time.



                            TABLE OF CONTENTS



EXECUTIVE SUMMARY   . . . . . . . . . . . . . . . . . . .  .  .  5

BACKGROUND . . . . . . . . . . . . . . . . . . . . . .  . . . .  6

EVIDENCE COLLECTION . . . . . . .  . .  . . . . . . . . . . . .  7

LABORATORY ANALYSIS AND TESTING. . . . . . . . . . . . . . . .   8

ROOT CAUSE IDENTIFICATION. . . . . . . . . . . . . . . . . . .  13

IDENTIFICATION OF OTHER SUSCEPTIBLE ITEMS. . . . . . . . . . .  13

OPERATING EXPERIENCE REVIEW. . . . . . . . . . . . . . . . . .  13

10 CFR 21 EVALUATION. . . . . . . . . . . . . . . . . . . . .   14

OPERABILITY ASSESSMENT . . . . . . . . . . . . . . . . . . .    14

CORRECTIVE ACTIONS. . . . . . . . . . . . . . . . . . . . . .   14



     PHOTODOCUMENTATION



     ATTACHMENT I   -    CONTACTOR APPLICATION SCHEMATICS



     ATTACHMENT II  -    VENDOR DATA



     ATTACHMENT III -    METALLURGICAL REFERENCE



     ATTACHMENT IV  -    HARDNESS TEST AND MATERIAL ANALYSIS

                         DATA



RCE 95-010                                             August 11, 1995



                            EXECUTIVE SUMMARY



At the return to service of Component Cooling Water Pump 3P026, on June

13, 1995, the control room had no indication from the breaker when the DC

was turned on.  The subsequent investigation determined that an

electrical contact finger had broken in the stationary secondary contact

block for the 4KV breaker in 3A0605.



Laboratory analysis of the failed contact block and three other contact

blocks of the same vintage revealed that the root cause of failure was

the use of hardened, brittle brass material in the manufacturing of the

contact fingers.  Cracks and work hardening were induced in the finger

bends during fabrication.  Mechanical cycling during removal and

insertion of the breaker further hardened the material eventually causing

an overload fracture.



The corrective actions for this event are identified as follows:



     -Provide an operability assessment for the affected Safety Related

     trains.



     -Issue NCR's against each Class 1E 4KV Switchgear with operability

     requiring checking of proper functioning after racking in the

     breaker.



     -Ordered replacement Class 1E contact blocks from ABB with

     verification that the strips meet the current specification which is

     a softer material and not susceptible to cracking.



     -Replace all Class 1E Unit 3 Train A contact blocks during the Unit

     3 Cycle 8 outage in July/August 1995 and evaluate the removed

     contact blocks for-cracking problems.



     -Replace Class 1E Unit 2 Train A and B and Unit 3 Train B contact

     blocks during scheduled online equipment outages with full

     replacement complete no later then the end of the U2/3, Cycle 9

     outage.



     -Sent failed contact block to ABB for Part 21 evaluation.



                                    5



RCE 95-010                                             August 11, 1995



                               BACKGROUND



At the return to service of Component Cooling Water Pump 3P026, on June

13, 1995, the control room had no indication from the breaker then the DC

was turned on.  The subsequent investigation determined that a finger in

the stationary secondary contact assembly (referred hereafter as the

"contact block") for the 4KV breaker in 3A0605 had broken.  The contact

block was removed and delivered to the Root Cause Group for failure

analysis and Root Cause Evaluation.  Reference NCR 95060044 and MO

95060799001.  The following NCR's were written to address the operability

of the Class 1E 4KV Switchgear:



                         NCR 95060065 Bus 2A04

                         NCR 95060069 Bus 2A06

                         NCR 95060070 Bus 3A04

                         NCR 95060071 Bus 3A06



The Busses are considered operable based on a seismic review,

verification of contact connection when the breaker is racked in, and the

fact that the fracturing of the contact block fingers only occurs when

racking in/out the breakers.  A detailed discussion is in the operability

Assessment section of this report.



Three (3) additional contact blocks were supplied to support the

analysis.  The first sample was a contact block from spare position

2A0602, removed under MO 95060832.  The second sample was an unused

warehouse stock unit.  The third sample was removed from the Salt Water

Cooling Pump 2P114, breaker location 2A0611, under MO 95061249.  The

2P114 contact block was selected because there had been a relatively

large number of rack in/out cycles on the breaker.  All three samples are

of the same manufacturing vintage as the failed unit.



                                    6



RCE 95-010                                             August 11, 1995



                           EVIDENCE COLLECTION



The contact blocks were originally manufactured for ITE Metal-Clad 4KV

switchgear by Brown Boveri as part number 834838-T1.  The material Code

for the block is 026-26208.  The current vendor, ABB Power T&D Company,

was contacted and they have no history of problems with the contact

blocks.  The specification sheet and Critical Characteristic Analysis for

the contact block fingers was obtained for correlation of the laboratory

analysis data.  The specification sheets are in the attachments to this

report.



A review of maintenance history revealed only two (2) failures in 155

breakers in the past 15 years.  This includes the current failure in

3A0605 and a failure in 1990 in 3A0606 documented in NCR 90090043.  The

1990 failure was considered an isolated incident.



An NPRDS search revealed no records of failed contacts on ABB breakers.



Nine utilities with ABB 4KV breakers were contacted and they have not

experienced any problems with contact block finger breakage with the

exception of a contact finger failure at Waterford which was caused by

misalignment of the breaker when racking it in.



                                    7



RCE 95-010                                             August 11, 1995



                     LABORATORY ANALYSIS AND TESTING



The contact fingers were arbitrarily numbered 1 through 12 to the

analysis.  These contact numbers correspond to the electrical connection

numbering scheme in the following way:



Analysis            Electrical

Numbering           Numbering



     1                   5

     2                   7

     3                   13

     4                   14

     5                   3

     6                   1

     7                   6

     8                   9

     9                   10

     10                  15

     11                  4



     12                  2



3A0605 Contact Block



Preliminary examination of the 3A0605 contact block revealed that one of

the contact fingers ( #4) was fractured at the 90 degree bend at the

inside end of the long section.  See Figures 1, 2 and 3.  The four bends

in the contact fingers are designated A through D.  See Figure 4.  The

fracture and cracks on this contact block are at bend C. Cracks were

present in two other contact fingers (#9 & #10) at the same location.

See Figures 5 and 6.



Scanning Electron Microscope examination (SEM) of the fracture face on

contact 4 revealed a fresh intergranular fracture which is a sign of

embrittled material.  See Figure 10.  Energy Dispersive Spectroscopy

(EDS) of the contact finger surface revealed that it was silver plated.

See Figure 11.  EDS of the base material revealed that it was 70% copper

and 30% zinc which is a 70/30 brass.  See figures 12 and 13.  No

contamination was present on or near the fracture surface.



                                    8



RCE 95-010                                             August 11, 1995



The fractured area of contact 4 was mounted for metallurgical gross

sectioning and the sample was cross sectioned from the side into the base

metal.  Microhardness testing.was performed on the base metal at bend B

and in the straight section between bend B and the fracture area at bend

C.  The Rockwell Hardness, b scale at the bend was 91.  The Rockwell

Hardness, b scale, in the Straight area was 71.  This data indicates that

the bend area is hardened and embrittled in the bend area.  All of the

Hardness testing data is in an Attachment to this report.



Optical microscope examination of the cross sectioned fracture area on

contact 4 revealed a grain structure indicative of Extra and temper.  See

Figure 7.  Intergranular cracks extended into the brass from the fracture

face.  The fracture face was also along grain boundaries.  Optical

microscopy of the cross section bend B revealed a small intergranular

crack in the inner diameter of the bend.  The grain structure in the bend

area was characteristic of Extra Hard temper.  See Figures 8 and 9.  The

grain structure in the straight.  area, away from the bend, was

characteristic of Hard temper.



The mechanical fatigue test was performed on the 3A0605 Contactor Block

to determine the number of insertion and removals were required to

fracture the cracked fingers.  A fixture was fabricated with the mating

contacts to the same dimensions as on the breaker.  Finger 12 fractured

on the thirty-second insertion in the fixture.  The finger fractured

across the preexistent crack at bend C.



Optical Emission Spectrometry was Performed on samples from all 12

contact fingers.  The analysis confirmed that the base material was 70/30

brass in all cases.  The Current ABB specification for the contact

material is Alloy 230 which is an 35% copper, 15% zinc brass which is

less brittle than Alloy 260, 70% copper, 30% zinc.  The material

specification was changed to alloy 230 in 1982.  Information from the

vendor on the material specification prior to 1982 was not available.



                                    9



RCE 95-010                                        August 11, 1995



2A0602 Spare Contact Block



Optical microscope inspection of the 2A0602 contact block revealed that

nine of the twelve contact fingers had cracks.  The cracks were mostly on

the outer diameter of bend B and D.  The inner diameter of the bends

could not be inspected until the fingers were removed.



The contact block was disassembled by mechanical means.  First,

made to open bend D but four of the five fingers bend during this

process.  It is significant that 10 was removed by opening the D bend and

the crack.  It was decided that the most effective way fingers was to cut

them in half along the straight procedure keeps the bend areas intact for

analysis.



Contact 10 was subjected to several cycles of reverse bending at an

original bend area and no cracks developed.  The finger was cross

sectioned.  Examination of the microstructure revealed that the grain

structure in the straight area was characteristic of Half Hard temper and

the grain structure at the bend was characteristic of a less brittle

material and consequently less work hardening.  See Figures 14 and 15.

Metallurgical examination of other fingers revealed the same Extra Hard

temper condition as on the failed contact block.



Microhardness testing on contact 7 revealed a Rockwell hardness, b scale,

of 72 and 94 on the straight and bent areas, respectively.  Microhardness

testing on contact 10 revealed a Rockwell hardness, b scale, of 76 and 90

on the straight and bent areas, respectively.  Note that the Hardness

numbers are similar for both contacts while contact 10 is significantly

more ductile as indicated in the microstructure.  Microhardness is not a

sensitive indicator for slight variations in material temper.



                                   10



RCE 95-010                                             August 11, 1995



Warehouse Contact Block



Optical microscope examination of the unused contact block obtained from

the warehouse revealed cracks at the outer diameter radius of the B bend

on all the contact fingers.  The contact fingers were removed from the

block by sawing the fingers in half at the center of the straight

section.  Inspection of the inner diameter of the bends revealed cracks

in all the samples at the B bend.



Contacts 7 and 8 were examined in the SEM to document the surface

cracks at bend B.  See Figures 16 and 17.  Both contacts were cross

sectioned to determine the depth of the cracks and the microstructure.

The inner diameter crack on contact 7 was deep, approximately one third

of the thickness of the contact.  See Figures 18 and 19.  The grain

structure at the bend was characteristic of Extra Hard temper and the

grain structure in the straight area is characteristic of Hard temper.

The cracks on contact 8 were shallower than those on contact 7.  See

Figures 20 and 21.  The grain structure at the bend was characteristic of

Extra Hard temper and the grain structure in the straight area is

characteristic of Hard temper.



Microhardness testing on three contacts revealed the following Rockwell

Hardness, b scale, data:



Contact        straight area       bend area

  4                 83                  90

  7                 78.5                91.5

  8                 76                  91.5



The material condition of the unused block is similar to that of the

failure and the spare block.  The unused block from the warehouse is to

be of the same vintage as the blocks installed in the plant.



                                   11



RCE 95-010                                             August 11, 1995



2A0611 Contact Block



The contact block was removed from the plant because it was installed on

Salt Water Cooling Pump P114 and is considered to have a large number of

insertion and removal cycles.  See Figures 22 and 23.



Optical examination of the contact fingers revealed cracks on the outer

diameter of the B Bend on contacts 2, 5, 6 and 11.  See Figures 24

through 27.



The contact block was cycled in the test fixture 500 times and the cracks

did not grow perceptibly.  The test cycling was so extensive that the

silver plating was scraped off the brass fingers.  This test demonstrated

that cracks in the fingers do not necessarily grow to fracture in the

short term.



New Contact Finger Material



In the process of reordering contact blocks for replacement of all unit 3

Train A applications during the U3C8 outage, a sample of twenty contact

finger bars were obtained from ABB.  Elemental analysis of the bars

revealed that they were Alloy 230, 85% copper and 15% zinc in accordance

with the current ABB specification.  The Rockwell b scale hardness was

found to be in the range of 40-60.  According to the ASTM B36 Standard,

the material is in the Quarter Hard temper range which is less likely to

crack in the contact block application.  Microstructural analysis

revealed that none of the fingers had cracks in the bend area and the

grain structure was characteristic of Quarter Hard in the straight area

and Half Hard in  the bend area.  See Figures 28 through 31.  Based on

this analysis, production of the replacement contact blocks was

authorized.



                                   12



RCE 95-010                                             August 11, 1995



                        ROOT CAUSE IDENTIFICATION



The root cause of the fracturing of the finger on the 3A0605 contact

block was improper material used in the finger construction.  The 70/30

brass used in the older (Pre-1982) contact blocks is too brittle for the

application.  Examination of the other contact blocks supports the

conclusion that cracks originate at the bends during fabrication due to

work hardening of the brass.  The variation in material hardness accounts

for the degree of cracking and susceptibility to fracture during the

stress of removal and insertion of the associated 4KV breakers.



                IDENTIFICATION OF OTHER SUSCEPTIBLE ITEMS



This type of connector is associated with 64 Class 1E 4KV breakers in 4

buses and 91 Non-1E breakers in 8 buses in Units 2 and 3.  All of the

affected breakers have been identified by Station Technical.



                       OPERATING EXPERIENCE REVIEW



As discussed in the Evidence Collection section of the report there were

no reports of failed contacts in ABB breakers in the NPRDS data base.



The manufacturer, ABB Power T&D Company, was contacted and they have no

records or recollection of fractured contact fingers.



Nine power plants, with the same kind of breakers, were contacted by

Station Technical.  One contact failure event occurred at Waterford due

to breaker misalignment during rack in.  Several other plants reported

breaking of the plastic frame due to breaker misalignment during rack in.

The plants contacted were Waterford, Vogtle, Catawba, Crystal River,

Limerick, Zion, Prairie Island, Hope Creek and Beaver Valley.



                                   13



RCE 95-010                                             August 11, 1995



                           10CFR21 EVALUATION



ABB Power T&D Company of Sanford, Florida is currently analyzing contact

block finger material from SONGS and several other sources.  As soon as

the testing and data gathering are complete, ABB currently intends to

issue a 10CFR Part 21 Report covering the broken and cracked contact

finders.  If ABB does not issue a 10CFR Part 21 Report, than ISEG will

evaluate the need to write a 1CFR Part 21 Report on the defective contact

blocks discovered at SONGS.



                         OPERABILITY ASSESSMENT



Seismic Considerations



The control fingers are not stressed by a seismic event because the

control assembly is supported firmly by the circuit breaker and cubicle.

The circuit breaker is held in place firmly by its attachment to the bus

and cubicle.  Therefore, the control fingers do not support any seismic

loads and fractures of the control fingers would not be caused by a

seismic event.



All 4kv breakers contain these stationary secondary contact blocks

which provide breaker control and indication.



The breakers are operable for the following reasons and under the

following conditions:



Operational Considerations



The secondary contact control fingers provide power for four different

functions.  Control fingers 2 and 5 provide for the charging of the

breaker control spring.  When the breaker is racked into the operate

position from the disconnected position, and the DC control power is

applied, the breaker control spring will be charged.  This action is

quite noisy and readily apparent.  If the breaker control spring has not

been



                                   14



RCE 95-010                                             August 11, 1995



discharged, the charging spring motor will not be heard upon closing of

the DC control power.  Spring charging can be verified after the first

breaker operation by either hearing the charging spring motor operate

(per above) or by viewing the "SPRING CHARGED CAUTION" tag through the

breaker viewing port in the lower right hand corner of the breaker

cubicle door.  Caution tag is located at either bottom right or left

center of the circuit breakers front.



Control fingers 13 and 14 provide the green, circuit open indication.

This indication is received at the local cubicle door and in the control

room when the DC is turned on and the breaker open.



Control fingers 6 and 7 cause the breaker x y scheme to operate closing

the breaker.



Control fingers 9 and 10 (for all breakers except the Diesel Generator

breakers) provide the trip path and also provide the red indicating light

when the breaker is closed.  Any time the breaker is closed the red light

performs the function of monitoring the breaker trip path.  If the red

lights are on (when the breaker is closed) the trip path is operable.



For the diesel generator breakers, the red light does not monitor the

trip Coil.  T-F the red light is on (with the breaker closed) then

contact fingers 14 (also used in green indicating lights) and 15 are

functioning properly.  And, if the Diesel Generator circuit breaker trips

by operator control action at the end of its run, then secondary control

fingers 9 and 10 are operating properly.



Whenever a circuit breaker is returned to service, operations as a normal

routine, functions it to show operability of the equipment.



To determine that all 1E breakers presently racked into the operating

position have their control springs charged, station technical inspected

all breakers (through the sliding cubicle



                                   15



RCE 95-010                                             August 11, 1995



door) on 2A04, 2A06, 3A04 and 3A06 at approximately 1100 hours on

6/21/95.  Each breaker racked into the energized position had its control

spring charged.



Restricted Operability



1.   Any time a breaker is racked out of the connected (racked in)

     position, to be considered operable after having been returned to

     the connected (racked in) position it must:



     a.   Verify charging spring charges when DC is applied to breaker

          cubicle, or, if charging spring was not discharged, verify

          spring is charged after the first operation by inspection (per

          above) .



     b.   With the breaker open and DC power on, green indications lights

          must be observed at the proper locations.



     c.   Close the breaker and observe red indicating lights at the

          proper locations and the load is energized.



     d.   For the Diesel Generator Breakers only, red indicating lights

          must be illuminated at the proper locations and the diesel

          breaker must be tripped by operator control action at the end

          of the appropriate diesel run.



                                   16



RCE 95-010                                             August 11, 1995



                           CORRECTIVE ACTIONS



Non-Conformance Reports have been issued against each Class 1E 4KV

switchgear to require operability verification after the breaker is

racked in.  These NCR's are NCR 95060065 for Bus 2A04, NCR 95060069 for

Bus 2A06, NCR 95060070 for Bus 3A04 and NCR 95060071 for Bus 3A06.



New contact blocks have been ordered from ABB to replace the blocks in

the plant.  The contact finger material has been verified to be the

correct Quarter Hard 85/15 brass as discussed in the Laboratory Analysis

section of the report.



All of the contact blocks in Unit 3, Train A, will be replaced during the

U3C8 outage in July/August 1995.  The tracking documents for this

activity are the above mentioned NCR's.  An MO has been written for each

cubicle and each MO references the associated NCR.  The removed contact

blocks will be evaluated by ISEG/RCG for the degree of cracking and the

results will be used to validate the overall replacement schedule.



All of the remaining old type contact blocks will be replaced in Unit 2

Train A and B and Unit 3 Train B during Scheduled Equipment outages with

all the blocks being replaced no later that the end of the Cycle 9 outage

on both Units.



The failed 3A0605 contact block was sent to ABB, Power T&D Company for

failure analysis and Part 21 evaluation.



                                   17



                           PHOTODOCUMENTATION



RCE 95-010                                             Photodocumentation



Figure 1: "Optical photograph of the failed 3A0605 contact block. Note

the fractured finger at location #4." omitted.



Figure 2: "Optical photograph of the back of the 3A0605 contact block

showing the fracture at finger #4. omitted.



RCE 95-010                                             Photodocumentation



Figure 3: "Optical photograph of one end of the fractured finger #4 at

bend C.  Crack in finger #9 is on lower right." omitted.



Figure 4: "Optical photograph of a finger showing the labeling of the

bends.  Bend D was fractured during removal." omitted.



RCE 95-010                                             Photodocumentation



Figure 5: "Optical photograph of the crack in finger #9, at bend c, on

the 3A0605 contact block." omitted.



Figure 6: "Optical photograph of the crack in finger #12, at bend c, on

the 3A0605 contact block." omitted.



RCE 95-010                                             Photodocumentation



Figure 7: "Optical Micrograph of a cross section of one the finger #4

fracture showing the intergranular cracks and extra hard temper grain

structure.  Mag:200X" omitted.



RCE 95-010                                             Photodocumentation



Figure 8: Optical Micrograph of finger #4 cross section at bend B showing

a crack at the inner diameter and the extra hard temper grain structure

at the bend.  Mag:50X" omitted.



RCE 95-010                                             Photodocumentation



Figure 9: "Close-up of the inner diameter crack in finger 4, bend

B in Figure 8.  Mag:400X" omitted.



Figure 10: "Scanning Electron Microscope (SEM) photograph of the fracture

face on finger 4 showing the intergranular structure." omitted.



RCE 95-010                                             Photodocumentation



Figure 11: "Energy Dispersive spectrum (EDS) showing the elemental

composition of the plating on the surface of finger #4, contact block

3A0605." omitted.



RCE 95-010                                             Photodocumentation



Figure 12: "EDS of the base metal of 3A0605, finger #4 showing copper and

zinc are present." omitted



RCE 95-010                                             Photodocumentation



          15-Jun-1995    15:53:37       CONTACT #4, FRACTURE



     Accelerating voltage                    20.0 KeV



     Beam - sample incidence angle           60.0 degrees



     Xray emergence angle                    29.0 degrees



     Xray - window incidence angle            1.5 degrees



                        STANDARDLESS EDS ANALYSIS

                      (ZAF CORRECTIONS VIA MAGIC V)



     ELEMENT         WEIGHT        ATOMIC         PRECISION

     & LINE         PERCENT       PERCENT*        2 SIGMA   K-RATIO**



     Cu KA          69.19          69.79          0.69      0.6959

     Zn KA          30.81          30.21          0.54      0.3093



     TOTAL          100.00



ITERATIONS             4



*NOTE: ATOMIC PERCENT is normalized to 100



**NOTE: K-RATIO = K-RATIO x R

     where R = reference(standard)/reference(sample)



               NORMALIZATION FACTOR: 1.000



Figure 13: Table of copper and zinc elemental percentages in the EDS

spectrum in figure 12.  The material is 70/3 brass.



RCE 95-010                                             Photodocumentation



Figure 14:  "Optical micrograph of bend C on finger #10 from the Spare

2A0602 contact block.  The grain structure shows why this finger was more

ductile than the others.  Compare to Figure 8. Mag:50X" omitted.



Figure 15: "Close-up of the grain structure at the bend area of figure

14.  The larger gains are a less hard temper than the cracked fingers.

Mag: 200X" omitted.



RCE 95-010                                             Photodocumentation



Figure 16: "SEM photograph of contact finger #7 from the warehouse

contact block showing the cracks at bend B." omitted.



Figure 17: "Close-up of the cracks in Contact #7, bend B, in Figure 16."

omitted.



RCE 95-010                                             Photodocumentation



Figure 18: "Optical micrograph of the cross section of contact finger #7,

bend b, showing the depth of the cracks. Mag:50X" omitted.



Figure 19: "Close-up of the inner diameter crack in finger #7, bend B, in

Figure 18.  Mag:200X" omitted.



RCE 95-010                                             Photodocumentation



Figure 20: "Optical micrograph of the cross section of contact finger #8,

bend b, showing the depth of the cracks.  Mag:50X" omitted.



Figure 21: "Close-up of the inner diameter crack in finger #8, bend B, in

Figure 20.  Mag:200X" omitted.



RCE 95-010                                             Photodocumentation



Figure 22: "Optical photograph of removal of the 2A0611 contact block

after removal from the P114 breaker." omitted.



Figure 23: "Optical photograph of back of the 2A0611 contact block

showing the location of the cracked fingers." omitted.



RCE 95-010                                             Photodocumentation



Figure 24: "Close-up of the crack in finger #2, bend B, in contact block

2A0611." omitted.



Figure 25: "Close-up of the crack in finger #5, bend B, in contact block

2A0611." omitted.



RCE 95-010                                             Photodocumentation



Figure 26: "Close-up of the crack in finger #6, bend 3, in contact block

2A0611." omitted.



Figure 27: "Close-up of the crack in finger #11, bend B, in contact block

2A0611." omitted.



RCE 95-010                                             Photodocumentation



Figure 28: "Cross sectional micrograph of the new contact finger material

in the bend area showing a grain structure indicative of Half Hard

temper.  Mag:50X" omitted.



Figure 29: "Magnified view of the new material at the bend area showing

the absence of cracks.  Mag:200X" omitted.



RCE 95-010                                             Photodocumentation



Figure 30: "Cross sectional micrograph of the new contact finger material

in the straight area showing a grain structure indicative of Quarter Hard

temper.  Mag:50X" omitted.



Figure 31: "Magnified view of the new material in the straight area

showing the acceptable grain structure.  Mag:200X" omitted.



              ABB Combustion Engineering Nuclear Operations



                       CERTIFICATE OF CONFORMANCE



Customer:                     Certificate Number 1          Page 1 of 1

NAME ABB Power T&D-Sanford,FL Certificate Is CONDITIONAL [] Order is

                                                            INCOMPLETE []

                                           UNCONDITIONAL[X]      COMPLETE

[X]

ORDER NO. P311407-00          Record Checklist Attached YES NO

LATEST REV. NONE                                        [X] [ ]

                         ABB CE Order No. 406265 - 01 Supplement No. 0



Cust.     ABB CE     Quality       Part Number    Description

item#     Item#     Order   Ship



1         1.0       3         3    701902C00      Material Analysis of

                                                  Secondary Contacts-3/6

                                                  samples.



2         2.0       3         3    816978A00      Material Analysis of

                                                  Secondary Contacts-3/6

                                                  samples.



3         3.0       6         6    81697BA00      Material Analysis of

                                                  Secondary Contacts-6/6

                                                  samples.



As checked off; the following apply to the item(s) and /or services being

certified:



     [ ]  Nuclear Spare Paris Quality Assurance Program description

          (QAM-300), revision 09.



     [ ]  System Staging Group Quality Assurance Program (QAM-400),

          revision 01.



As checked off; the following method(s) for acceptance apply:



     [ ]  Source Verification           [ ] Dropship/Receiving Inspection



     [ ]  Post Assy Test/Inspection     [ ]  Documentation Review



     Whereby this order has been processed in accordance with the ABB

     Combustion Engineering Nuclear Quality Assurance Manual (QAM-100),

     4th Edition, revision 2, dated 2/1/95 and any of the above checked.

     ABB hereby certifies that the item(s) and/or services described

     above meet the referenced purchase order requirements, including

     applicable codes, specifications, standards and equipment

     qualification requirements.  Any exceptions to these requirements

     have been documented and evaluated properly executed deviation

     notices as noted within this documentation.  Additionally; this(s)

     and or services is supplied from ABB/CE's facility at Windsor, Ct.

     or from a supplier that has been previously approved by ABB/CE

     Windsor, Connecticut.



Comments: (1) THIS CERTIFICATION PROVIDES RESULTS OF MATERIAL ANALYSES

ON

SAMPLE SECONDARY CONTACTS PROVIDED BY ABB POWER T&D, DISTRIBUTION

SYSTEMS

DIVISION, SANFORD, FL (2) THIS WORK WAS PERFORMED TO VERIFY

COMPLIANCE

WITH MATERIAL/PROCESS SPECIFICATIONS AS DEFINED ON ABB DRAWING

701902,

REV, 6 AND 816978, REV. 7, THESE SPECIFICATIONS INCLUDED:...BASE

MATERIAL: C.F. BRASS #2, ALLOY 230,... SILVER PLATING: ABB SPEC. 51664A,

REV. 5 (3) COPIES OF ORIGINAL TEST REPORTS AND PHOTOGRAPHS WILL BE

FORWARDED BY MAIL.



Distribution:

               Quality Assurance File

               Purchasing File



Engineering                             QA Representative        Date



Other                                   M. W. STEWART



Customer       ABB POWER T&D                 N/A                   N/A

                                        Cognizant Engineer       Date



COFCE 3/95                    ATTACHMENT #2



ATTACHMENT "ABB Combustion Engineering Nuclear Operations RECORDS

CHECKLIST (RCL)" omitted.



DIRATS                                            TEST REPORT

LABORATORIES



Tom S. Preston                               Report Number    226979

ABB Combustion Engineering                   Report Date    29-AUG-95

Nuclear Spare Parts                          Page             1 of 2

P.O. Box 500 M/S 9425-DH24                   Client Number     004400

Windsor, CT 06095-0500                       Client Order   406265-01

                                             Release        ITEM 1.0



RECEIVED       6 Contacts

IDENTAS        P/N 701902C00

MATERIAL       .050 CF Brass #2, Alloy 230

               Silver Plated

CONDITION      *

TEST TO        ITE 51664A Rev. 5 and Client Instructions

TEST PER       *

PURPOSE        *

SPEC INST      Return specimens and 3 unused parts



PROPERTIES AS SUPPLIED



SEMI-QUANTITATIVE SPECTRO CHECK OF PLATING                       Disp

     S/N 1                                                    In Spec

     The spectrographically detectable elements

     are present in approximately the required

     amounts for Silver.



     S/N 2                                                    In Spec

     The spectrographically detectable elements are

     present in approximately the required

     amounts for Silver.



     S/N 3                                                    In Spec

     The spectrographIcally detectable

     elements are present in approximately

     the required amounts for Silver.



QUANTITATIVE ANALYSIS BY XRF

Sample         1              2              3

          Base Metal     Base Metal     Bass Metal

%

Cu             84.91          84.91          85.16

Fe             <0.01           0.01          <0.01

Pb              0.01          <0.01          <0.01

Zn           REM           REM             REM

Cu + sum of

named

elements       99.99          99.95          99.99

Disp:       For Info       For Info       For Info



The symbol < signifies not detected at the defectability limit Indicated.



DIRATS                                                 TEST REPORT

LABORATORIES



ABB Combustion Engineering              Report Number       226979

Nuclear Spars Parts                     Report Date         29-AUG-95

Windsor, CT 06096-0500                  Page                2 of 2



HARDNESS TEST Of BASE METAL



Sample         Hardness                                              Disp

1              HR30T 67                                          For Info

2              HR30T 67                                          For Info

3              HR30T 66                                          For Info



Note: No authorized hardness conversion table for this material.



METALLOGRAPHIC EXAMINATION OF PLATING                               Disp



Sample: 1                                                        In Spec

     Thickness: Min.  0.00005", Max. 0.00010", Predom,

     0.00005"



Sample: 2

     Thickness Min. 0.00005",  Max. 0.00010", Predom, 0.00010"   In Spec



Sample: 3 In Spec

     Thickness: Min. 0.00005", Max. 0.00010", Predom,  0.00005"  In Spec



WE CERTIFY THIS IS A TRUE COPY OF OUR RECORDS

Signed for J. Dirats and Co. by Richard C. Simmons, Technical Manager

NOTE: The recording of false, fictitious or fraudulent statements or

entries an this document may be punished as a felony under federal law.



DIRATS                                            TEST REPORT

LABORATORIES



Tom B. Preston                               Report Number       226980

ABB Combustion Engineering                   Report Date      29-AUG-95

Nuclear Spare Parts                          Page                1 of 2

P.O. Box 500 M/S 9426-DH24                   Client Number       004400

Windsor, CT 06095-0500                       Client Order     406265-01

                                             Release           ITEM 2.0



RECEIVED       6 Contacts

IDENTAS        P/N 816978A00

MATERIAL       .050 OF Brass #2, Alloy 230

               Silver Plated

CONDITION      *

TEST TO        ITE 51664A Rev. 5 and Client Instructions

TEST PER       *

SPECINST       Return    specimens and 3 unused parts



PROPERTIES AS SUPPLIED



SEMI-QUANTITATIVE SPECTRO CHECK OF PLATING                       Disp

     S/N 1                                                    In Spec

     The spectrographically detectable elements are

     present in approximately the required

     amounts for Silver.



     S/N 2                                                    In Spec

     The spectrographically detectable elements are

     present in approximately the required amounts for Silver.



     S/N 3                                                    In Spec

     The spectrographically detectable elements

     are present In approximately the required

     amounts for Silver.



QUANTITATIVE ANALYSIS BY XRF

Sample         1              2              3

          Bass Metal     Base Metal     Base Metal

%

Cu             85.55          85.46          85.57

Fe             <0.01           0.01           0.01

Pb             <0.01           0.01          <0.01

Zn           REM             REM            REM

Cu+ sum of

named

elements       99.98          99.95          99.99

Disp:       For Info       For Info       For Info



The symbol < signifies not detected at the delectability limit

Indicated.



DIRATS                                                 TEST REPORT

LABORATORIES



ABB Combustion Engineering              Report Number       226980

Nuclear Spare Parts                     Report Date      29-AUG-96

Windsor, CT 06095-0500                  Page                2 of 2



HARDNESS TEST OF BASE METAL



Sample    Hardness                                               Disp

1         HR30T 68                                          For Info

2         HR30T 68                                          For Info

3         HR30T 68                                          For Info



Note: No authorized hardness conversion table for this material.



METALLOGRAPHIC EXAMINATION OF PLATING DLSP



Sample: 1                                                   In Spec

     Thickness, Min. 0.00010", Max. 0.00010",

     Predom. 0.00010"



Sample: 2                                                   In Spec

     Thickness; Min. 0.00010", Max. 0.00010",

     Predom. 0.00010"



Sample: 3                                                   In Spec

     Thickness: Min.0.00005", Max. 0.00010",

     Predom.  0.00010"



WE CERTIFY THIS IS A TRUE COPY OF OUR RECORDS

Signed for J. Dirats and Co. by Richard C. Simmons, Technical Manager

NOTE: The recording of false, fictitious or fraudulent statements or

entries an this document may be punished as a felony under federal law.



DIRATS                                                 TEST REPORT

LABORATORIES



Tom B. Preston                               Report Number  226981

ABB Combustion Engineering                   Report Date    29-AUG-95

Nuclear Spare Parts                          Page           1 of 3

P.O. Box 500 M/S 9426-DH24                   Client Number  004400

Windsor, CT 06095-0500                       Client Order   406265-01

                                             Release        ITEM 3.0



RECEIVED       6 Contacts

IDENTAS        P/N816978A00 Second Lot Identified as SCE1 thru SCE6

MATERIAL       .050 CF Brass #2, Alloy 230

               Silver plated

CONDITION      *

TEST TO        ITE 51664A Rev. 5 and Client Instructions

TEST PER       *

PURPOSE        *

SPECINST       Return specimens



PROPERTIES AS SUPPLIED



SEMI-QUANTITATIVE SPECTRO CHECK OF PLAYING                         Disp

     S/N SCE1

     The spectrographically detectable elements are present      In Spec

     in approximately the required amounts for Silver.



     S/N SCE2

     The spectrographically detectable elements are present      In Spec

     in approximately the required amounts for Silver.



     S/N SCE3

     The spectrographically detectable elements are present      In Spec

     in approximately the required amounts for Silver.



     S/N SCE4

     The spectrographically detectable elements are present      In Spec

     approximately the required amounts for Silver.



     S/N SCE5

     The spectrographically detectable elements are              In Spec

     present in approximately the required amounts for Silver.



     S/N SCE6                                                    In Spec

     The spectrographically detectable elements are

     present in approximately the required amounts for Silver.



DIRATS                                                      TEST REPORT

LABORATORIES



ABB Combustion Engineering              Report Number            226981

Nuclear Spare Parts                     Report Date 2         9-AUG-95

Windsor, CT 06096-0500                  Page                     2 of 3



QUANTITATIVE ANALYSIS BY XRF

Sample       SCE1           SCE2           SCE3          SCE4

          BASE METAL     BASS METAL     BASE METAL     BASE METAL

%

Cu             85.68          85.58          65.67          85.80

Fe             0.01           0.01           0.01           0.01

Pb            <0.01          <0.01          <0.01          <0.01

Zn           REM            REM            REM            REM



Cu and sum

of named

elements:      99.97          99.98          99.99          99.98



               For Info       For Info       For Info       For Info



Sample         SCE5             SCE6

            BASE METAL        BASE METAL

%

CU             85.69               86.78

Fe              0.01                0.01

Fb            < 0.01               <0.01

Zn            REM                   REM



Cu and sum

of named

elements:      99.99               99.99



             For Into            For Info



The symbol < signifies not detected at the defectability limit indicated.



HARDNESS TEST OF BASE METAL



Sample         Hardness                                        Disp

SCE1           HR30T 67                                     For Info

SCE2           HR30T 67                                     For Info

SCE3           HR30T 67                                     For Info

SCE4           HR30T 67                                     For Info

SCE5           HR30T 67                                     For Info

SCE6           HR30T 68                                     For Info



Note:     No authorized hardness conversion table for this material.



DIRATS                                                 TEST REPORT

LABORATORIES



ABB Combustion Engineering                   Report Number       226081

Nuclear Spare Parts                          Report Date      29-AUG-95

Windsor, CT 06095-0500                       Page                3 of 3



METALLOGRAPHIC EXAMINATION OF PLATING                               Disp



Sample: SCE1                                                     Off Spec

     Thickness: Min, 0.00010", Max. 0-00020",

     Predom.  0.00010"'; see photo.



Sample: SCE2                                                     Off Spec

     Thickness: Min. 0,00010", Max 0.00020",

     Predom.  0.00020"'; see photo.



Sample: SCE3                                                     In Spec

     Thickness: Min. 0.00005".  Max. 0.00010"',

     Predom. 0.00010"



Sample: SCE4                                                     In Spec

     Thickness: Min, 0.00005", Max. 0,00010",

     Predom., 0.00010"



Sample: SCE5                                                     In Spec



     Thickness: Min. 0.00005", Max. 0.00010",

     Predom, 0.00010"



Sample: SCE6                                                     In Spec

     Thickness: Min. 0.00005", Max. 0,00010",

     Predom, 0.00010"



PHOTOGRAPHS ARE ATTACHED



WE CERTIFY THIS IS A TRUE COPY OF OUR RECORDS

Signed for J. Dirats and Co. by Richard C.  Simmons, Technical Manager

NOTE: The recording of false, fictitious or fraudulent statements or

entries on this document may be punished as a felony under federal law.



Attachment #3 "HP Switchgear Which may incorporate Alloy 260 conductor

strips with possible forming cracks into secondary disconnect assembly"

omitted.



*** END OF DOCUMENT ***



Page Last Reviewed/Updated Thursday, March 29, 2012