Product
Line
Component
All HK
Arc Chutes
Foreign material found - 2 metal plates wedged in
arc horn.
All HK
Arc Chutes
"Sand" found in arc chutes.
All HK
Arc Chutes
All HK
Arc Chutes
All HK
Arc Chutes
Evaluation of cracks in ABB HK Arc Chutes.
ABB recommends NOT shipping arc chutes while
mounted on breakers.
ABB offers refurbishment of arc chutes in some
cases.
All HK
Arc Chutes
Arc Chute Jump Gap Cracks/Repairs - Arc chute
issues with jump gap cracks, epoxy repairs, etc.
What are other plants using as acceptance criteria
when finding damage to arc chutes? Do any plants
have any testing or inspection criteria. David
answered some with gaps…Vogtle still finding
cracks.
All HK
Arc Chutes
Is ABB going to develop field repair procedure?
All HK
Arc Chutes
What is the Status on repairing Arc chutes?
All HK
Arc Chutes
There is a long lead time for HK arc chutes – They
are also expensive. Can you justify repairs?
Issue
All HK
Aux Switch
SWGR
Aux Switch
L2 Aux Switches binding due to excessive NO-OX
grease used by supplier.
Perry Presentation - L2 Aux Switch (TOC) found
out of adjustment resulted in breaker failure.
All HK
Aux Switch
Aux Switch refurbishment technique
All HK
Aux Switch
L-2 Switch Maintenance
All HK
Aux Switch
L-2 Switch Failures
Aux Switch
OE16527 - Loose Linkage in 4KV Breakers Results
in Failure of Auxiliary Contacts at Oconee (L2 Aux
Switch)
Aux Switch
OE 16739 - Breaker Cell Switch Failure Caused
Essential Cooling Water Pump Trip Event
(L2 Aux Switch)
All HK
All HK
All HK
Aux Switch
All HK
Aux Switch
OE17451 - Reverse Power Trip of Diesel Generator
Because of a Misaligned Breaker Auxiliary Switch
Breaker Auxiliary Switches Missing Internal
Spacers. The missing spacers could allow the
contacts to slide on the shaft to a point where the
electrical contacts would not make connection or
prevent the switch from rotating.
All HK
Aux Switch
ABB Refurbishment Review
SWGR
Aux Switch
Refurbishing & Replacing Cubicle Mounted Aux
Switches (Jim Allgood)
SWGR
Aux Switch
Adjustment travel on L2 switches…can ABB
provide guidance on adjustment & switch setup?
All HK
Chair Moldings
All HK
Chair Moldings
Evaluation criteria for hair-line cracks.
Chair Moldings Prior to 1970 (may have) different
mounting location for the puffer nozzle.
All HK
Charging Motor
Brush Length Spec on Spring Charging Motor
All HK
Charging Motor
OE 16879 - The Spring Charging Motor on a
4.16KV Breaker Overheated
All HK
Charging Motor
Charging Spring Motor Failed to Operate due to
excessive brush wear and charring.
All HK
Charging Motor
Obsolescence of older Lamb / Ametek motors.
All HK
Charging Motor
What type of grease should be used in Ametek
Charging Motors.
All HK
Charging Motor
15HK
Closing Spring
All HK
Closing Spring
All HK
Coil - Trip & Close
All HK
Coil - Y
Trip and Close Coils
Oconee has reported a potential problem with
varnish buildup on the inside of the bobbin of the Y
coil in their control devices.
All HK
Contact Springs
Stationary contact assembly block spring relaxation
Overhaul Maintenance of Spring Charging Motor
OE20142 (Perry) Breaker Identified with Incorrect
Closing Spring Combination
Combination found was "Gray-Red-Gray" which
documentation does not support
Color & type of closing springs…can ABB give a
chart?
All HK
Contacts
Have seen cracked moving arcing contacts on
HK breakers in the past couple of years, maybe
1 in 10 breakers. Has anyone else in the
industry seen this type of event?
All HK
Control Circuit
OE16764 - ABB 5HK and 15HK Series Breaker
Blocking Diode Failures
All HK
Control Device
Use of "BBs" versus "Slugs" for control device
contacts.
5HK Trucks
Control Device
Adjustment criteria
15HK Trucks
Control Device
Adjustment criteria
All HK
Control Device
Broken contact carrier.
Control Device
ABB January 2001 10CFR21 issued - Moving
contact tip (spring seat) failure @ Seqouyah and
Catawba. During manufacturing, the contacts were
overformed which made them thin. Only three
known cases
All HK
Control Device
Should Control Device Springs be replaced during
Control Device refurbishment?
All HK
Control Device
Silver plating on Aux contacts is wearing off. How
critical is silver plating on contacts?
All HK
Control Device
OE16387 - Breaker Problem Caused Component
Cooling Pump Manual Start
All HK
Control Device
All HK
Control Device
All HK
OE18438 - 4KV Breaker Control Device Contact
Carrier Manufactured with Excess Molding Material
Containment Spray Pump Breaker Failed to Close
Using the Control Room Control Switch during
Surveillance Testing due to improper adjustment of
the auxiliary contact device. A contributing cause
was inadequate instruction in both the vendor
technical manual and the preventative maintenance
procedure.
All HK
7.5HK
5HK350
Control Device
ABB Metal Clad Circuit Breaker Contact Forming
Concern (Contacts Improperly Formed)
Control Device
Failure on Control Device that was rebuilt. 7.5HK
has two gaps…overtravel & stop lever. Gaps were
within specs.
Control Device
15HK
Control Device
All HK
Control Device
7.5HK
Control Device
SWGR
CTs
SWGR
Cubicles
All HK
Drawings
15HK
Drawings
All HK
Hold Pawls
All HK
Inspection - NRC
OE18438 Breaker Failure to Close Due to Control
Device Contact Carrier Manufactured with Excess
Molding Material
OE19937 Swgr Cubicle Interference Prevented Bkr
from Operating
Closing springs did not recharge after last breaker
operation due to impact of closing springs' link arm
with swgr interference bracket on the floor of the
cubicle
ABB Refurbishment Review
(Hope Creek) 7.5HK Breaker Failed to Close due to
Control Device Failure
Retaining spring for "LSa" detached due to
inadequate height of spring retainer and spring with
BB may have contributed.
CT liquification.
Isolation between adjacent cubicles to prevent
ionized gas transfer (ref SONGS 2001 failure)
Revision of HK Exploded View Drawings
15HK Contact, Truck, Jackshaft, Op Mech
Exploded View Drawings
OE18435 - 4KV Breaker Spring Charging Failure
What findings resulted from the 1998 NRC breaker
"pilot inspections"?
a) If cracks are found in the bus bars ceramics
what could be the cause? b) What criteria is used
by ABB to determine acceptability? If the megger
readings are acceptable, do cracks pose any
negative impact on the integrity of the bus bars ?
SWGR
Insulators
All HK
Interference Angle
All HK
Interference Angle
OE19076 (Sequoyah) 1E Breaker Installed in N1E
Application
What is the proper location of the Interference
Angle (i.e. rejection bracket) for all HK models?
5HK Trucks
J-Hooks
Seabrook & Perry discovered 5 “J” hooks with partthrough wall cracks on the inner radius of the bend
and 1 fractured during breaker retest after
refurbishment
All HK
Latch Spring
All HK
Latch Spring
SWGR
Lead Assembly
North Anna Issues (OE 15980 - 4/2003)
SWGR
Lead Assembly
Issues identified at Surry (5/2003)
OE 17213 - Auxiliary Feedwater Pump Breaker
Failed to Close Because of a Weak Latch Spring
OE17906 - 4 kV ABB HK Breaker Charging Spring
Cycling
SWGR
Lead Assembly
Lead Bushing inspections during SWGR PM.
All HK
All HK
Lubrication
Lubrication
All HK
All HK
Lubrication
Lubrication
What mechanical lubricants are approved?
What electrical lubricants are approved?
What amount of NO-OX should be applied to
breakers?
Do heaters in the cubicle degrade grease?
All HK
Lubrication
1) Mobil28 is being used & timing is too short. Can
ABB provide timing spec for M28
2) Can we increase bridge pivot pressure?
3) Can overtightening cause galling?
All HK
Lubrication
OE 17796 - Condensate Pump Slow Breaker
Opening Due to Hardened Grease
5HK
MOC Actuator
Assembly parts upgraded and need to be replaced
if you replace your lower frame / truck assembly
and it be of the old style (ABB provided a picture of
old & new style assembly)
All HK
MOC Linkages
All HK
MOC Linkages
All HK
MOC Linkages
Notes from discussion on MOC Linkages
Diesel Output Breaker Failed to Open due to
Misaligned mechanism operated control switch. A
design weakness of the MOC linkage attachment
can result in the locking nut falling out such that the
breaker control logic is disrupted.
Seabrook MOC alignment failure & failure analysis
report (OE24048).
All HK
Operating Mechanism Spurious Closure of Breaker
All HK
OE 17374 - Inside Recirculation Spray Pump
Circuit Breaker Failed to Close Due To Mechanical
Operating Mechanism Binding
All HK
Circuit breaker failed to close while attempting to
start a Safety Injection pump. The cause of the
breaker's trip free condition was interference
between the pin in the third toggle assembly and
the wall of the mechanism or the side of the
charging cam. This interference occurred due to
the use of undersized washers found on the shaft
of the crank assembly. The wear caused by the
rubbing of the end of the pin on the cam and the
side sheet caused increased friction as the surface
became rough which eventually caused the trip
Operating Mechanism latch to bind and caused the breaker to fail to close.
ABB supplied HK Swgr Shutter / MOC /TOC part
numbers and recommended maintenace
frequency.
SWGR
Parts
All HK
Parts Kit - Breakers
Incorrect Parts Identified in Vendor-supplied
Breaker Refurbishment Kit
All HK
Parts Kit - Breakers
Some parts are impregnated with Anderol.
All HK
Parts Kit - Breakers
What refurb parts kits are offered by ABB?
All HK
Pin - 3rd Toggle
All HK
Pin - Close Latch
All HK
All HK
Pin - Shutter Roller
Pin - Shutter Roller
3rd toggle pin cracks & fractures.
Older style pins used cotter pins on both sides
which could cause close latch return to hang up on
manual close lever.
Cannot Remove Breaker from Cubicle due to
shutter kick pin grabbing wireway.
SONGs shutter kit pin event. Loss of 1E Bus.
SWGR
PM - Ductoring
SWGR
PM - Grounding
All HK
PM - Inspection
All HK
All HK
PM - Inspection
PM - Inspection
What is the ABB and/or Industry maximum DLRO
reading for bus connections ? Based on Surry
experience, connections were mostly between 3 or
4 micro-ohms, generally less than 6 micro-ohms.
What means or device do other plants use to
ground the bus?
What is the ABB recommended inspection
frequency?
What is the EPRI-NMAC CBUG concensus
inspection frequency?
What are the recommended inspection tasks?
All HK
PM - Inspection
Indications of lubrication problems
Is there a more effective cleaner (solvent) other
than isopropyl alcohol that can be used to clean
bus stabs & silver plated bus connections without
damaging the silver plating surface?
ABB Bus Connection Torque Values
SWGR
SWGR
PM - Inspection
PM - Inspection
SWGR
PM - Inspection
All HK
PM - Inspection
SWGR
PM - Meggering
All HK
PM - Receipt
All HK
PM - Receipt
All HK
PM - Refurbishment
All HK
PM - Refurbishment
All HK
PM - Refurbishment
Shipping Damage
During receipt inspection of a refurbished safetyrelated breaker it was identified that the U-channel
that operates the auxiliary switch on the breaker
was installed incorrectly.
What is the ABB recommended refurbishment
frequency?
What is the EPRI-NMAC CBUG concensus
refurbishment frequency?
(1) In case of Plant refurbishment (after about 30
years life), shall the breakers be refurbished or
replaced? What is recommendation from OEM and
what is industry practice? How many plants have
(a) replaced or (b) refurbished breakers during
Plant refurbishment? What is preferred breaker
type (e.g. vacuum or air?)
(2) What is maintenance / refurbishment frequency
observed by industry these days?
All HK
PM - Refurbishment
What do people do for cleaning secondary
disconnects on either k-Line or Hk.
ABB MV Swgr & Bus Maintenance (John Layne)
Can get slow close in spec with go-no-go at
minimum..then difficulty getting in spec with fast
close.
What is the ABB and/or Industry minimum
acceptable megger reading for 5HK switchgear
bus?
All HK
All HK
PM - Refurbishment
PM - Storage
All HK
PM - Testing
Breaker refurbishment interval - MV HK breakers,
what are some peoples experiences from 10y-15y?
Catawba is now back to 10 years.
Storage requirement for breakers – not installed.
Reduced Voltage Testing Presentation (Beaver
Valley)
All HK
PM - Testing
Is reduced (minimum) voltage testing required?
All HK
PM - Testing
What values should be used for reduced voltage
testing?
SWGR
PM - Thermography
All HK
Post Maint Testing
MISC
MISC
MISC
MISC
MISC
SWGR
Presentation
Presentation
Presentation
Presentation
Presentation
Primary Disconnect
All HK
Primary Disconnect
In the past ABB stated (including tech bulletin) that
thermography can be performed to determine the
conditions of connections and switchgear
equipment. But industry experience indicates that
thermography alone is not adequate. Most of the
switchgear components cannot be monitored
through thermography. Does ABB have a
recommended method on modifying switchgear
cabinets or other means to monitor bus
connections while equipment is energized ?
INPO Inspection Issue concerning breaker & relay
PMT
Safety Presentation - Woodbury Substation
Accident
PSEG Breaker Program
INPO Safety Presentation - Ken Sweet
AVO Arc Flash Presentation - John Lane
NMAC SOER 98-2 Refresher Presentation
Songs Presentation- Cubicle misalignment
SONGS Presentation - 2001 failure of 3000A
feeder breaker. Primary disconnect condition &
traveling ionized gas issues.
All HK
Primary Disconnect
Prairie Island Presentation - 2001 Failure & Fire
All HK
Primary Disconnect
Primary Disconnect maintenance.
All HK
Primary Disconnect
Primary Disconnect / over-heating inspection.
All HK
Primary Disconnect
HK Primary Stab Maintenance CD-ROM
All HK
Primary Disconnect
Primary Disconnect
ABB Breaker tulip springs dislodged due to shutter
binding
Questions
1) Issues pertaining to arcing & sputtering of
breaker / cubicle connections
2) Information on Primary stab design changes
3) Size/rating of breakers found with these
problems
All HK
All HK
All HK
Primary Disconnect
Questions (cont. from above)
Primary Disconnect
Prairie Island 4kV Swgr Fire
Catastrophic failure in breaker cubicle (apparent
cause failure of PDA, though specific cause hard to
determine due to damage). Subsequent
investigation at other breaker cubicles led to the
determination that baked No-ox on the bus stabs
create high-resistance connect that led to the
failure.
5HK
Primary Disconnect
All HK
Primary Disconnect
All HK
Puffer Piston
All HK
Push Rods
5HK
Racking Mech
All HK
All HK
Ratchet Plate
Ratchet Plate
OE19227 Overheating of Breaker PDAs
Causes:
• Slight misalignment of breaker stab
• Dried deposits of No-ox on rosette contact surface
• Non-silver plated copper rosette fingers
ABB Refurbishment Review
Aging Failure of Puffer Piston on ABB Type HK
Breaker. The puffer piston shaft had failed due to
age related embrittlement and fatigue.
Limerick identified hair line cracks on rush rod
baffles (all 3 phases).
OE20459 (Seabrook) Emergency Bus Reserve
Transformer Breaker Failed to Close
Bkr mechanical interlock failed to go into the proper
position when racked in, preventing bkr closure.
Condition due to inadequate procedure guidance &
lack of individual knowledge related to positive latch
engagement during racking.
Teeth on ratchet plate breaking off…not cause,
symptom. Charging motor will run continuously. Is
a higher control voltage (131 - 135 vdc) a
contributor?
Mispunched Rachet Plate (Fermi)
All HK
Ratchet Plate
MISC
Retrofit
OE18435 Breaker Spring Charging Failure
Sequoyah MV Vacuum Breaker Retrofit Experience
(Presentation)
All HK
Retrofit
Has anyone replaced their breakers (HK) with a
Vacuum?
All HK
Retrofit
OE18006 Breaker Failed to Trip Electrically
All HK
Retrofit
All HK
Retrofit
Lessons Learned on Med. Volt. Replacements
Presentation - DC Cook Vacuum Replacement
Experience & OE
SWGR
Male Secondary Disconnect inspection (cubicle
Secondary Disconnect mounted). 1995 BVPS failure resulted in 10CFR21.
All HK
HK Breaker Secondary Disconnect Connection
Problems after racking the Breaker into the
Cubicle. Has anyone else experienced this
Secondary Disconnect Issue?
5HK250
All HK
SWGR
All HK
SWGR
Secondary Disconnect OE18906 Breaker Failure to Operate in Test
Secondary Disconnect Secondary Disconnects Maintenance
Loss of silver plating on Swgr (male) Secondary
Disconnect causes 1E breaker failure.
Secondary Disconnect (Hope Creek)
OE 16633 - ABB HK-Style Breaker Spring Clip
Shutter Roller Retainer Loosening
Swgr shutters becoming detached from shutter lift
mechanism.
Shutters
Shutter nylon hardware fractures & failures.
ABB recommended maintenance and parts list.
SWGR
SWGR
Shutters
Shutters
All HK
All HK
Silver Plating
Silver Plating
Inspection acceptance criteria.
TVA Questionaire on Silver Plating
All HK
Silver Plating
Are any plants doing silver plating?
All HK
Silver Plating
a) What thickness of silver should be applied to the
primary disconnect? b) Are the requirements for
silver plating the same for both the breaker Primary
Disconnect and Swgr Lead Bushing?
All HK
Silver Plating
Silver Plating of Parts
All HK
Spring - Tension
PART 21 NOTIFICATION - DEFECTIVE HK AND
K-LINE CIRCUIT BREAKER TENSION SPRINGS
Spring - Tension
This is more of an FYI for the group:
KLine – Had two failures back to back. Compressors
Broken tension spring. Similar to Part 21 this year
(3-16-2009). Part 21: Look at replacing around
1500 cycles? This one failed at about 700 cycles.
These breakers were used as starters (on
compressors)Part number: 716539A00.
All HK
All HK
Spring Discharge Lever Spring Discharge Lever Damaged
All HK
Spring Guide
All HK
Spring Guide
15HK Trucks
All HK
All HK
Spring Guide
Survey
Survey
All HK
Trip Latch
All HK
Trip Roller
All HK
Troubleshooting
Found with cracked welds - is ABB intending to
improve the quality of the weld? Is stress coming
from slow close bracket as cracked weld is closest
to slow close bracket tab
Limerick found broken tack-welds on the closing
spring guides.
Inner Spring Tube (p/n 193309-K01) has black
Alkyd resin coating. It has been determined that
lubricant (Anderol, MG28) removes the resin
coating & causes additional friction which can lead
to closing speed changes, which negatively affects
the breaker operation and/or can lead to a failure to
fully close the breaker.
Duke Overhaul Breaker Survey
Who utilizes high speed video equipment
Trip Latches with riveted pins.
Trip Roller denting after few operations (i.e. "soft
rollers")
Troubleshooting - Paul Zamarripa - Prairie Island.
NSR 5HK250 having problems with breaker not
operating properly. Verified close circuitry. Testing
cannot determine problem. Any suggestions on
what to look for? Testing?
Failure of breaker to operate from control switch.
Cubicle issue. 2nd breaker tried in same cubicle
with same results.
Resolution
ABB believes this fell into arc chute before / during mfg. Due to age of arc
chute, no telling how this happened.
Contact ABB-Florence (HK Product Engr) for CCRP generation. Arc Chute
manufacturer process defect.
See referenced EPRI Document
Damage is likely to occur. If you value your arc chutes, don't ship them.
Discussion on types that can and can't be repaired not included in
Powerpoint presentation.
ABB has document prepared by Ward Laubauch of KEMA. Sharkey’s
observation is that we are not really looking at this. Ron F. says most people
will find cracks if they look. ABB working on internal procedure that is not
complete…was working on procedure for TVA…work in progress. EPRI
perspective is that we were going to validate this procedure developed by
KEMA to determine set of acceptance criteria. Needs to be two phase effort.
Phase one is evaluation which is complete (2002)…issue is still open…is
there still interest to proceed…do we need to move forward with phase two of
testing and validation? ABB can repair arc chutes…however, older arc
chutes that have the outer moldings that are glued together can only have
the bundle replaced. ABB will repair some arc chutes in Florence, others
have to be returned to original manufacturer. KEMA evaluation will be
distributed with meeting minutes. 5HK250 and 7.5HK500 were two types of
arc chutes we were going to test.
David Hatfield: There is a procedure that he has developed for ABB, but has
not been issued to industry…see KEMA eval comments. Sharkey says EPRI
might fund this if we show interest or a need in this item (ABB will not fund
this)…warns to be prepared for test results…findings might raise concerns
with arc chutes in service. Testing is destructive testing of arc chutes and
will require damaging several arc chutes to validate results. Note: report is
now available on EPRI NMAC CBUG website.
ABB can not repair or refurbish Arc chutes. Piedmont Dielectric is the
current manufacturer of the arc chute. New arc chutes are available from
ABB.
Q: Are certain areas of arc chutes more prone to cracking? Yes, the jump
gap is most susceptible to cracking (it also contains asbestos). Don’t lay arc
chutes on their sides.
Q: Additional question on arc chutes Where do you test the arc chute. See
picture. Both sides of the Blow out coil
Build up stock of arc chutes.
7 plants leave their arc chutes at their switchgear.
Don’t’ store arc chutes on their side – it limits damage from using them as a
table/bench.
Must remove old NO-OX-ID grease during maintenance / refurb and replace
with new grease. ABB recommends that the L2 switch is replaced after 8000
operations (if rotated contacts at 4000) or 10 years
FYI
*Document each contact configuration (e.g. - A,B,A,B).
*Totally
disassemble entire auxiliary switch.
*Remove old NoOx-ID grease that is found.
*No-Ox-Id
lubricant has been found along the stationary connection (rear) that can
cause failure (open circuit) due to cohesion.
*Inspect silver plating,
replace any piece that is missing silver plating.
*During assembly,
place No-Ox-Id lubricant only at pivot area (lower area, can not be seen
unless disassembled).
*Do not lubricated the
mating/wiping surfaces.
Paul Zamarripa - Prairie Island. Maintenance recommendations for L2
switch on truck? Are any plants replacing L2 switch during PM, overhaul or
as corrective action for problem history?
ABB pretty much covered this information.
Survey says: 18 plants now present
Breaker switch: 11 during breaker overhaul
Cubicle switch: 4 (STP does when overhauling breaker…replaces L2 switch
without de-energizing switchgear). McGuire is going to do the same. Both
plants state it takes approximately 6-8 hours to replace the switch + time to
make any necessary adjustments to linkages. ABB asked if it would make
the process easier if they provided the switch on the mounting plate…both
plants indicated it would not.
Allen Dickard - Catawba. Survey of plants with L2 switch failures over past
two years (approximately):
# Plants being surveyed:
• Which were actual failures of the L2 auxiliary switch? David Hatfield knows
of 6 switch failures.
• Which failures were related to linkage and/or breaker switch actuator?
David knows of 4 failures related to linkage, which were also switch related.
STP did an analysis of switch failures and root cause of failures was
attributed to hardened lubricant (NO-Ox-ID).
Abstract: While investigating an unexpected alarm that occurred during
performance of an outage electrical test, it was discovered that the alarm
was being initiated by an L2 auxiliary switch contact. Investigation of the
switch revealed that the linkage had become loose from the actuating rod of
the breaker. This was due to a retaining nut that had come off of the linkage
connection point.
Cell switch contact to the MOV did not close during the pump start and the
pump tripped as designed. The apparent cause was an excessive amount of
corrosion inhibitor (NO-OX-ID grease) applied during manufacture of the
switch that had aged and behaved as an insulator. There was no formal
maintenance requirement to remove the old grease, and this material
resulted in degraded performance of this specific switch.
The cause of the failure was that an L2 auxiliary switch on the ABB 5HK250
1200 amp incoming breaker did not correctly change state when the breaker
was closed. This occurred due to failure to check for proper auxiliary switch
alignment in relation to breaker open/closed status prior to placing the
breaker in service.
The apparent cause is a supplier problem. There were no breakdowns in the
Perry procurement process or its implementation. The specific supplier
cause may be determined as the result of ABB’s initiation of CAR
#200700073 to have a Part 21 investigation performed. This seems to be a
manufacturing issue.
• Document each contact config (e.g. - A/B, fast B, etc.)
• Totally dis-assemble entire aux switch
• Remove old No-ox grease (No-ox lubricant has been found along the
stationary connection (rear) that can cause failure (open circuit) due to
cohesion
• Inspect silver plating & replace any piece missing silver plating
• During re-assembly, place No-ox only at pivot area (lower area, can not be
seen unless dis-assembled
• ABB can provide switches without No-ox - contact ABB for new part
number
FYI
ABB: There are 4 types of crank arms and different setting adjustments on
links. There are multiple holes on link arms - need to mark which link arm
hole is connected when breaker is disassembled prior to refurb. Might look to
see if link is bent. Plate that the switch is mounted to is two separate
plates...3 bolts, but cannot adjust plate (though there may be some play).
There is a new style plate that can be purchased that will allow for some
adjustment.
EPRI test results on McGuire moldings available. Cracks can be a result of
leaning breakers on side or rear. ABB letter Issued to EPRI with TD-9608
and TD-9609 which give guidelines for Chair Molding acceptance criteria
If chair molding is replaced then a new nozzle and tube may be required.
Glenn Gorniak - Limerick.
Is there a specification for the minimum
brush length on the spring charging motor?
• Lamb/Ametek
• Ryobi
• Black and Decker
Action Item: ABB will provide this information, including part numbers for
Lamb/Ametek and Ryobi brushes and cap holders. John Layne will need to
confirm that these parts are still available through ABB.
Misrouting the wiring harness during overhaul of the circuit breaker by a
vendor. During the breaker overhaul the control devices are removed and
replaced. The wiring harness for the control device was inappropriately
routed under the control device instead of over the top of the device.
ABB (Gene Langlois) warned that there is some risk of doing more damage
than good when you are doing maintenance. ABB: You can take a static
resistance. There are several different types of motors. Anything below 50
ohms is acceptable. Can megger and spin to look for dead spots.
New breakers supplied with Ryobi motors. ABB can refurbish the older
Lamb/Ametek motors but not the Black & Decker motors. Motor change
outs to Ryobi requires additional qualification (and additional parts) and not
recommended at this time.
Bruce Renton of ABB. ABB motors had Beacon Exxon grease. During
refurbishment, all Beacon grease should be removed and replaced with
Anderol.
Lonnie Little - STPEGS. What kind of maintenance is being performed on
the spring charging motor during breaker overhaul? Has had some
problems and is considering replacing motors during overhaul. Wants to
know if any other plants are replacing motors. ABB replaces SONGS,
Progress Energy, PPL motors during overhauls if motors do not pass receipt
inspection.
Salem performs inspection of brushes and continuity check of motor rotor on
K-Lines (<10 ohms 125vdc motors while rotating gears). NOTE: ABB’s
recommendation is 34.5,,,see K-Line notes.
See OE
Color code is important. ABB has AI to provide information.
Have any plants experienced problems with broken retaining posts on trip
and close coils? DC ground on breaker traced to this. FYI to look for during
refurbishment. North Anna has seen this issue. Gene Langlois says coil
should not be able to turn inside casing. Gentille has seen this problem.
ABB inspected several coils and it appears while there is some varnish
buildup on the inside of the bobbin we have not been able to reproduce this
mode of failure.
Main contact springs wearing out…if breaker has been closed for lengthy
period…ABB is recommending that these springs be replaced.
ABB: Common to see indentations, and wear on these parts.
Brunswick – Have received some contacts from Florence that are cracked in
the center of the contact tip.
Turkey point – When would you expect to see contact wear/damage.
ABB: The higher the MVA rating the more wear you will experience.
Has anyone seen failures were the crack starts? Yes but not in the nuclear
world. 75% tungsten – 25% silver.
Blocking diode in the close control monitoring circuit had failed. The failed
diode created an electrical path that kept the anti-pump relay energized
which prevented the closing coil from being energized during an automatic
actuation. The cause of the blocking diode failure were manufacturing
defects in the die extending from the cathode to the anode that resulted in
high electrical leakage.
Use the newer design "slugs". Redesign due to BBs falling out of place.
Part numbers are: (5) Spring 712895A00 (5) Slug (solid washer) 650362F00
See ABB referenced IB
See ABB referenced IB
Attributed to improper control device adjustment, quick/repetative or extreme
cycling.
BBC and Gould decals on the side of control devices were blue in color and
all are suspected bad. ABB is red decal and is not affected by 1/01
10CFR21. The 10CFR21 recommends to replace the control the device. If
the customers feels that they are qualified enough to simply replace the
contacts then the springs and BB should be replaced with the round slug
and new type springs.
ABB David Hatfield: All the springs are required to be replaced and only a
tiny dab of no-ox grease should be applied at the pivot point (no grease on
the contact).
ABB: Zero tolerance on loss of silver plating. Reference L2 IB for
maintenance recommendations. During refurbishment L2 is completely
disassembled. Plants measuring resistance of contacts during PM –
majority of plants take resistance measurements and do not replace the
auxiliary switch contacts when copper is showing if the contact resistance is
less than 1 ohm. Note: Dave Hatfield commented that single contacts can
be swapped around with good ones that are not being used in the circuit.
The cause of breaker 1ETB6 failing to close was a failure of limit switch 2
(LS2, contact 10 - 11), to make in the breaker close circuit in the control
device. There are two causes for the contact failure. One cause was most
likely improper assembly of the breaker's control device. The assembly
problem left the control device internals in a bind and caused an intermittent
open contact in the breaker's control device disabling the close circuit on the
breaker. This cause is not definite as the failure cannot be intentionally
repeated either by site persons or the equipment manufacturer. The second
cause was a weak lever arm return spring on the control device. This spring
was also found to be longer than the manufacturer's specifications. These
spring problems would result in less than adequate force on the lever arm
and would exacerbate any additional resistance to movement created by an
improper assembly. Discussions with the vendor concerning the springs and
spring specifications are still in progress.
Excess molding material ("flash") on the carrier assembly resulted in this
breaker failing to close.
Revise the 5HK250 and 5HK350 preventative maintenance procedure to
include auxiliary contact device adjustments and visual verification of
operation.
This information has been shared with the manufacturer. At this time no
response has been received in relation to this issue.
ABB: Are you using latest copy of IB (Last addendum, May 2001??, had to
do with C/D gap measurements). New IB has overtravel dimension. Need to
document overtravel with feeler gauges before removing C/D when damaged
which will allow ebb to evaluate this specification. ABB cannot assess failure
w/o knowing as found results.
• Extra material causes Yb contact to hang open
• This has been seen recently on a K-Line
• Two event reported to ABB in 2004 - 2005
• ABB entered a CCRP and is reviewing the issue
• Bkr did not charge after closing in cubicle but did operate outside of cube
• Op mech did not fully travel (after closure) resulting in the timing lever to
travel improperly, which caused the control device not to operate the limit
switch properly
• Material removed from interference plate corrected problem
• ABB made a new swgr interference plate mounting bracket
• Inspect contact carrier for excess molding which can cause moving
contacts to hang up
• Moving spring (p/n 702338D00) & BB (p/n 703956A00) need to be replaced
with new spring (p/n 712895A00) and solid washer (slug) (p/n 650362F00)
See OE (number unknown at time) Hope Creek Date 050422
All CT’s should be inspected. ABB issued Part 21 on liquifaction of CT’s on
April 17, 1989.
SONGS: The switchgear is not designed to be air tight. There is a bus bar
that goes from cubicle to cubicle. The intent is to simply minimize the
transfer of any ionized gases by eliminating unnecessary or excessive holes.
ABB: Simply minimize the openings – No effort should be made to create an
air-tight junction.
Kevin Mullen - Seabrook. Action Item to Sharkey: New HK exploded view
drawings have been provided to Jim Sharkey and need to be incorporated on
webpage.
FYI
The breakers hold pawls pins were bound in the carrier causing the holding
pawls to not engage quickly enough. The pawls were catching only a fraction
of the ratchet plate's tooth, which caused it to wear prematurely. The affected
breaker was repaired. All pawls, pins, the carrier and
the ratchet plate were replaced.
See 1998 HK CBUG Meeting Notes
a) Age and heat can cause cracking. b) If heat has caused cracks then the
insulation should be replaced. Hi-Pot testing (best) can be performed per the
IB to check insulation strength if cracks are found. This is Go/No-Go testing,
must maintain value for approx.. one minute. Only NETA has megger
maintenance testing criteria for megaohm values per voltage class. Doble
testing can be used also.
See OE
ABB Dwgs available (Reference ITE Spec TD-6931 for 5HK and ITE Sheet L8535 for 7.5HK & 15HK)
FYI - Seabrook and Perry simply want to make the users aware of this issue.
Plants may wish to inspect for this whenever convenient. Both ABB and
Grand Eagle has seen this problem. Part number is 00RM44772002 (ABB
Part Numbers 191638A00 (LH) and 191638B00 (RH).
Increased mechanical resistance of the breaker mechanism caused by a
random build up of tolerances from wear and case distortion which our
existing overhaul program did not identify, coupled with a significant
reduction in latch spring rotational torque capability (6 turn spring). The
stronger 5-turn spring was able to overcome the higher resistance, while the
6-turn spring could not.
The cause for this event is still under investigation, however,
The initial cause appears to be the charging latch spring tension.
Gene Langlois reported as found conditions:
● Upper & lower 3000 leads found overheated & missing >50% silver plating
(removed, replated, re-installed)
● Bus bar insulation overheated & cracking (removed, insulation removed &
replaced, replated then re-installed)
● Bus bar boots dried from overheating (replaced)
● Ckt Bkr PDAs overheated & missing silver plating (removed, replated, reinstalled)
● Ckt Bkr upper/lower lead assemblies overheated & silver plating discolored
(removed, replated, refurbished, re-installed)
● Shutters replaced
Gene Langlois reported as found conditions:
● Upper & lower 1200 leads found to have sputtering connections & missing
silver plating - not overheated (removed, replated and then new parts were
purchased & installed - See new part design discussion by John Layne)
● Bus bar insulation was fine but cracked in some cases - not removed
● Bus bar boots were NOT overheated but replaced
● 3000 amp ckt bkr PDAs were oxidized slightly but NOT overheated
(removed, replated (refurbished) & re-installed) - New style have different
springs (dimension & color)
● Ckt bkr upper & lower lead assemblies oxidized slightly & silver plating
discolored (removed, replated, refurbished, re-installed)
● Shutters replaced - Had to be re-positioned & Gene & Curtis to discuss.
• Users need to inspect the silver plating of primary lead bushing in
switchgear during de-energization of bus to check for conditions listed below:
• Missing Plating
• Hardened NO-OX-ID Lubricant
• Burned area (sputtering).
• Corrosion
• Switchgear lead bushings (stab) should have silver plating intact. If the
stabs are found to have missing plating then if possible, they should be
replaced or re-plated.
• Lead bushing stabs that are missing 50% or less plating at the penetration
point (1”), does not have gouges, nicks or sputtering connections, and can
not be replaced at that time, can be re-used if coated with NO-OX-ID.
• Switchgear Primary Lead Bushing Stab Burnt
Anderol 757 (obsolete), CGC-757-2 (Anderol replacement), Mobilgrease 28
NO-OX-ID
ABB: Thin film per the IB.
Answer: YES
1) Mobil28 is speeding breaker…tightening bridge pivot affects speed with
M28. ABB is not changing timing spec. Recommends adjusting breakers to
conform to timing specs.
2) Unofficially yes. Should have bridge pivot moving freely.
3) Not with enough lubrication. ABB will evaluate changing bridge pivot spec.
IB for HK has not been updated to allow use of M28. Dial bridge pivot in to
get speed. If too fast on closing but ok on trip can adjust springs. CAUTION
Bridge pivot will loosen over time...if too tight & tears silver plate condition will
worsen. Use force gauge when adjusting. Speed is adjustable by opening
springs...second by bridge pivot.
The breaker operating mechanism was disassembled. Several needle
bearings had hardened grease. This circuit breaker had not been overhauled
since initial installation. The cause of the slow operation of the circuit breaker
was due to not overhauling the breaker within the time period recommended
by the manufacturer. This is a well documented industry problem (See SOER
98-02)
New style part numbers:
1. Bolt (p/n 54390C04)
2. Flatwasher (p/n 54500H00)
3. Bushing (p/n 165322A00)
4. Nut (p/n 54400H00)
5. MOC actuator link assembly (p/n 187920K02)
• Need to check your dimension on the linkages
•
Check the rotation – Need 90 degree rotation.
• You
could have “wiring issues”.
• ABB has
built some aux switches dry (without grease) and are doing some
endurance testing. They have asked customers (Turkey Point) with dry
switches.
• ABB will accept
a PO that requires L-2 switches to be dry. ABB will disassemble tswitch,
clean out the grease, and rebuild the switch.
• STP
now uses dry switches.
• It is not
possible to buy individual switch parts. If a bad part is found, you must
discard or cannibalize for parts.
• See ABB
presentation for more information.
• To clean, STP uses alcohol and citrus cleaner.
The failed linkage connection was adjusted, reattached, and tightened.
Visual inspections were performed on all 62 of the Class 1E ABB 4 kV
breakers at SONGS to confirm that the MOC linkage lock nuts were properly
in place. Periodic preventive maintenance inspections have been initiated for
all ABB 4 kV breakers. A design change to the linkage connection is being
considered. Station incorporated step in procedure to check the tightness of
lock nuts.
See document
Dave Watkins - Perry. Had breaker that closed on its own. BV had breaker
do the same. Perry has ruled out any similarities between BV failure and
their breaker failure. Group feedback?
Only happens when going from zero energy state….only happens on initial
closure, then breaker will operate normally.
Hatfield: manual firing lever over-travel when installing breaker in cubicle
resets due to shock when breaker trips free. Has also seen issues when
installing front plate jamming manual close lever. Also links on manual firing
lever (old style with cotter pins vs. new design) might contribute to problem.
Mechanical binding due to interference between the moving parts of the
breaker 24J-4 operating mechanism. A spare breaker was refurbished with
a retrofit upgrade repair kit and installed as breaker 24J-4. The retrofit
upgrade repair kit improves the design by reducing the inherent gaps in the
operating mechanism.
Replaced the subject breaker with a spare breaker and completed
satisfactory testing. The removed breaker was overhauled (refurbished)
which included replacing the Operated Mechanism with a rebuilt mechanism.
Other similar breakers were reviewed and verified to be functional.
FYI
During implementation of a plant 4160 volt breaker refurbishment program,
an incorrect part was received in a 4160V breaker refurbishment kit.
ABB recomends to thoroughly clean all parts (new and used) to remove any
Anderol prior to adding Mobilgrease 28.
Per ABB, the lead time is 2-4 weeks on standardized overhaul parts kits.
Custom kits can be developed for a specific utility/plant. Large numbers of
kits may take longer to produce
Requires close inspection (including dye penetrant testing) and condition
based replacement.
New style pins (part # 148115A00) have head on one side.
Kevin Mullen - Seabrook. Plant has a 5HK breaker that cannot be physically
removed from the cubicle due to shutter kick pin grabbing wireway.
Possibility of cubicle shifting. Any other plants with similar issues of cubicles
shifting / settling? Any ideas of how to remove with bus energized. Hatfield:
Possible to wear PPE, use insulated pole/stick (fiberglass) to wedge wireway
enough to remove breaker.
Presentation
Field experiences has found that 10 micro ohm or less is acceptable. The
higher the current rating, the lower the values will be found consistently.
Grounding trucks, grounding breakers, grounding cables/clamps.
1 to 5 years (environment dependant)
Not to exceed 6 years.
See reference document Section 4
Ensure proper maintenance program to look for & correct:
● Bkr PDAs (lubrication baked on; Unable to rotate PDA; Springs have lost
tension and are discolored; Pitting caused by arcing; Discoloration of molding
around assembly)
● Overheating of contact structures such that No-ox liquified in upper/lower
contacts and ran onto molding & bkr frame
● Similar issue where lubrication will drip onto contacts causing arcing and
contacts to not reset properly
● Swgr stabs (hardened lubrication, loss of silver plating, greenish
substance, overheating, AVOID use of abrasive material that will damage
silver plated surfaces)
● Swgr Bus (hardened lubrication, damage to insulation material, boots
cracked & brittle, bus bar damage)
● Visual damage to bkr Arc Chutes
Citrus cleaners can be used (do not dilute) as long as residue is a removed
immediately with alcohol. Must Hi-Pot test if citrus is used.
ABB provided torque values
FYI
Fast close is final test for as-left…slow close is only for initial setup.
Only NETA has megger maintenance and acceptance criteria values.
Mike Jasurda - SONGS. Problems with shipping damage other plants are
experiencing? No others responded that they have seen any damage. ABB
states some of the problem might be with the carrier used for shipment. ABB
does have a preferred vendor that they recommend. SONGS contract
specifies use of one of their contract carriers. Hatfield recommends using
Emery Freight.
The U-Channel was removed and installed correctly to ensure the auxiliary
switch would operate correctly. The current vendor guidance was obtained
for determining breaker health and the maintenance procedures were
revised to the latest test methods.
10 years.
8 to 12 years.
The Vendor Recommend 10 Years and EPRI recommends 10-15 Years for
refurbishment.
Should we refurbish or replace? It depends on many factors that need to be
considered.
Follow up: Is a breaker life dictated by end of cycle life or a time based
replacement?
Yes – 10000 operations is the EOL for that breaker, even if it has not
reached 10 years. Additional factors apply.
Scotchbrite and alcohol.
Silverpolish.
SS Fine tootbrush, alchohol and rag.
Found anderol only lasts 10-12 years in their environment. For the ABB
breakers the users group found that the testing done in labs and industry
experience found that the life of anderol is about 12 years. Made the
guidance document say that the max frequency is 12 years and the OEM
recommends about 10 years. ABB is using cgc77 in leu of anderol grease
which is no longer made.
SOER 98-02 provides the basis for pre-installation testing
FYI
The NRC (David Skeen) currently views this as a trendable item and stated
that, although it is not required, the trending of reduced voltage test data is “a
good idea”.
Plants need to take into consideration control circuit voltage drops and
battery voltage after 4 hour station blackout periods (if applicable), or
whatever is the worst-case expected voltage for each particular breaker.
ABB: Do not modify switchgear to perform Thermogaphy. Check with
thermography experts to see if a “digitizer” type can be found that looks
beyond steel panels.
FYI
FYI
FYI
FYI
FYI
FYI
FYI - Breaker Primary Disconnect & Swgr Lead Bushing misalignment.
FYI - Silver plating of primary disconnects and primary lead bushing in
switchgear (i.e Corroded, Missing Plating, Hardened NO-OX-ID Lubricant)
FYI
ABB recommends replacing or silver plating all primary disconnects and
replacing garner springs during refurbishment of all breakers. Users need to
discontinue polishing (Roysen) the primary disconnects while completely
assembled. Causes degradation of the garner spring finish which leads to
rusting. Users need to inspect the lead bushings during de-energization of
bus to check for these conditions.
• Sputtering connections, arcing contacts, or pitting
• Difficulty in removing and/or rotating the tulip
• Dripping or hardening of NO-OX lubricant
• Appearance of silver – Not varnished
• Discoloration on leads (rainbow effect) or contacts
• Whiteness or discoloration of chair molding
• Lack of silverplating
• Cracked insulation on bus bars
• Cracked boots
• Arc chute insulation materials flaking
• Broken springs on tulips
Jim Sharkey – EPRI. HK primary stab and disconnect maintenance (breaker
and switchgear)
Action Item: Sharkey add info from CD.
Action Item: Dave Davis will send out survey of what maintenance plants are
performing with regard to primary stab/primary disconnect maintenance.
Inspection revealed that the switchgear cubicle shutter cover assembly
malfunctioned which caused tulip rubbing that forced the springs to be
dislodged. There was no failure or loss of breaker function.
Answers
1) Four factors identified
• Over time No-ox becomes hard when heated & become an insulator.
Current through connection with hardened burnt No-ox causes No-ox to burn
away causing sputter.
• Old breaker Primary Disconnect springs lessens connection point pressure
• Silver loss causing oxidation which increases connection resistance
• Improper alignment causing higher connection resistance
2) ABB Inc - Swgr Systems in Lake Mary, FL changed design in 4-18-02:
• The 5HK250 & 350, 1200 & 2000 amp primary stabs. Example p/n is
#838964A00 & #838964B00 (1200 amp model) and #838965A00 and
#838965B00 (2000 amp)
• Parts went from a four piece fabricated design to a one piece caste design
• New caste design eliminates significance labor (no fab assembly, just silver
plating) which allows for quicker turnaround time & less quality problems
caused during fabrication
• Part is easier to install & remove as new design has a threaded barrel &
machined contact surface instead of an inserted nut. The inserted nut has
been found to slip when installing or removing which can aggravate the
installation / removal. The machined surface gives more contact area for the
bus connection along with elevating any problems of loose nut.
3) 5HK250 & 350, 1200 & 2000 amp primary stabs. Example p/n is
#83896A01 & #83896A02 (1200 amp model). Age, heat & maintenance (lack
there of) are the primary factors in failures
Corrective Actions:
● Inspect circuit bkrs prior to connecting to bus
● Stopped use of abrasives such as scotch brite for cleaning terminal
connections as detrimental to silver plating
● Use of ground & test truck for measuring good PDA connection to bus.
Practice had been taking resistance measurement cube-to-cube / stab-tostab (typical 40 micro-ohm), but through use of test truck to measure through
PDA, was finding high resistance connections (typical 1,111 micro-ohm).
● Alternate method used for measuring ckt bkr contact resistance to include
PDA
● Explicitly call out inspection & cleaning of bus stabs in procedures
● Heightened awareness of condition of silver plated connection surfaces
CONCERN: During investigation 2 bkrs were inspected SAT (PDAs) installed
and 3 months later found all 6 PDAs on each bkr with significant overheating
damage. Thermography performed during the 3 months did not indicate a
hazard (perhaps due to thermography only being at single points in time).
ABB:
• Bkr only 6 yrs old; PDAs were replaced & swgr stabs checked for alignment
From OE:
• Installed upgraded design of breaker stab & rosette parts inspected for
silver-plating
• Procedures revised to address removal of no-ox grease on rosette contact
surfaces
• Users need to inspect the silver plating of the PDAs on the breakers more
closely to check for conditions listed below:
-- Corrosion
-- Missing plating
-- Hardened No-ox
-- Burned area (sputtering)
• Bkr PDAs should have the garter springs replaced & the finger contacts
should be 100% silver plated
• No gouges, nicks or sputtering connections shall be present on PDA
• Any 5HK350-1200 used in a 60kA fault duty application needs to have 2000
PDAs installed
• 3000 amp bkrs get new style garter springs which in some cases changes
the finger assemblies
All of the station 4 KV breakers are to be replaced with vacuum breakers that
do not have or need puffer assemblies.
FYI
See OE
ABB recommendation to replace with ratchet plate with 2 skipped tooth.
Cause is slow moving ratchet pawl…grease in wrong location applied
inappropriately…spring is probably weak. Breakers are designed for 140vdc
so this is not a contributor.
ABB Dwg Sheet 191745
• Last year discussed a 1979 CB with original hold pawls pins that were
thought to be binding in the carrier causing the holding pawls to not engage
quickly enough
• The pawls were catching only a fraction of the single missing tooth ratchet
plate's tooth, which caused premature wear. Broke one tooth.
• ABB has revised pawls & ratchet plate
• ABB has issued a preliminary report that indicates the following possible
causes:
-- Weak ratchet pawl spring
-- Dragging of the pawl due to spiral pin & lubricant placement
-- Heat treat of ratchet plate has irregular values such that teeth are not as
hard as plate itself
• ABB recommends to replace pawls & ratchet plate if problem found. DO
NOT lubricate on the side of the ratchet pawl.
FYI
McGuire has purchased some 5VHKX breakers but has not yet installed.
SONGS also have breaker replacements.
• 5VHK-R250 utilizing the K-Line type mech
• Roll-in-Replacement (RIR) for 4.16AMH250 designed by ABB services Inc
& qualified by CE Nuclear (now Westinghouse - BNFL)
• ABB has decided not to ever supply a 5VHK-R250 or 5VHK-X250 to
Nuclear Industry
• ABB will supply 5VHK-X350 for any 250 MVA RIR, which uses the K3000
Op Mech
Paul Battish - SONGS. Survey of plants with medium voltage vacuum
breaker conversions. Lessons learned. OE. Paul believes replacement cost
of new HK breaker is equal to roll-in vacuum replacement breaker. Sharkey
recommends reviewing EPRI document: “Considerations for Replacement of
….”
Rick Sparks has some industry experience to share and did presentation
during Siemens-Wyle meeting. TVA had significant issues related to
MOC/Cubicle interface (now resolved).
ABB reports the VHK does have any reported MOC/cubicle interface
problems. McGuire has installed 8 with no problems.
FYI
FYI
SONGS bumps their loads after they roll in a breaker. Occasionally find the
issue on their breakers.
Surry sees the issue also.
Fermi also has seen some of the same problems, and their operators rack
the breaker in and out 4-5 times to clean up the (wipe) contacts. They seem
to have good reliability.
• Secondary Disconnect was not making good contact
• Swgr & Bkr side secondary disconnects have been found oxidized and not
able to make good connection
• Inspections of swgr & bkr sec disc need to be performed to prevent such
failures
• Clean silver plated copper connection gently with scotchbrite should be
done if oxidation is found. CAUTION - these may be energized.
• These was an ABB Part 21 (8/1995) for swgr sec disc - cracking of the
dielectric material.
Paul Zamarripa - Prairie Island. What maintenance performed on secondary
disconnects in cubicle and frequency. Note: there is an old part 21 issue
(SONGS August 1995). Has had loss of indication (lights) attributed to
secondary disconnect. Most plants replaced secondary disconnect
assemblies…several plants did find faulty contact fingers. Alignment issues
should not occur due to play in secondary contact assembly on breaker.
Keith Smith…have you tried bluing to verify contact? Discussion of mounting
washers used as spacers. John Layne: TP/OP contacts…make sure screw
is tight on phenolic. Paul Battish had similar problem and had to install
addition washers on assembly to realign due to settling of switchgear. Keith
Smith also cleans contacts with scotch brite during switchgear maintenance.
Ron Ferrie cautions to not remove silver plating. Mark McClelland…what is
ABB doing to female secondary disconnects during refurb? ABB does not
disassembly disconnect…clean faces where they interact with male part with
alcohol. Is there No-OX on secondary disconnects? Hatfield says no….these
Frequency: Switchgear inspections TXU 3 yrs. STP 5 years. McGuire 5 year
FYI
During inspection of a 5HK breaker, the spring clip that holds the shutter
roller on the breaker was found missing. The roller was still attached to the
breaker and did not pose any problem with the operation of the breaker.
However, the missing spring clip could have allowed the roller to come off. If
this had occurred, the breaker could not be racked onto the bus due to the
interference caused by the shutter not being raised high enough.
Excessive wear identified on lift rods. Apply light film of mechanical lubricant
on lift rod. Perform routine inspections.
Shutter nylon hardware becomes brittle with age. Requires inspection and
condition based replacement.
FYI
ABB: Zero tolerance on loss of silver plating. Replace part if any silver
plating missing, especially critical at pivot/mating surfaces.
FYI
Three plants send off to third party for re-plating. None do their own replating. NLI will do it if you tell them the thickness (NLI will replate safety
related), Excel Energy Service Company, and Non-Safety: Rockwell
commons in Cedar Rapids – They can do anything, but don’t have an
Appendix B program.
a) Plating thickness on switchgear ranges from 0.00001 - 0.00005 (pre
1978) and 0.000025 - 0.00005 (1978 - now) depending on application. b)
Yes for Disconnect & Bushing plating thickness.
Lonnie Little - STPEGS. What parts can ABB not re-silver plate? ABB can
re-plate any part that has been previously re-plated. During the cleaning
process parts may be identified as having damage which will require
replacement. Breaker HK lower terminal has a pressed on part, if corrosion
is present, ABB recommends not re-plating.
David Hatfield did say ABB will re-plate bulk shipments and provide volume
discounts.
NOTE: ABB will re-plate silver products from any breaker (safety related or
not.
(Medium Voltage) and K-Line (Low voltage) circuit breakers. In the HK
breaker, the spring is used on the racking mechanism to position the racking
mechanism interlocking latch. Circuit breakers and spare parts procured
from ABB between 04/23/2008 and 02/27/2009 may have suspect springs
installed. Initial report of the nonconformance was generated on 02/11/2009
(NCR #68999JL)
Given the large number of applications for the affected circuit breakers, ABB
(Medium Voltage Service) cannot determine if the potential for a substantial
safety hazard exists at any licensee's facility if a similar failure of the tension
spring occurs. Licensees are requested to evaluate the history of inspections,
maintenance practices, and circuit breaker operating cycles for K-Line
breakers, and racking cycles for HK breakers to determine if the circuit
breaker spring should be replaced immediately or at the next convenient
maintenance opportunity. ABB recommends that any suspect spring with
greater than 1,400 operating cycles be replaced as soon as possible.
This issue was bounded by specific dates set forth in the Part 21. This is the
same spring on the HK Racking mechanism.
Gene Langlois – Waukesha (for North Anna). Spring discharge lever in floor
of cubicle damaged coupled with settling of floor caused springs to discharge
and breaker closing when racked to the disconnect position. FYI during
cubicle inspections. Visually inspect strike plate on cubicle floor.
ABB modified this part & has not seen any fail but some split open. ABB is
not going to do anything to upgrade this part…will continue to find cracked
welds and will have to replace these parts. Cracked welds will not cause
breaker to fail, however parts will continue to be rejected. ABB has AI to
provide applicability for Roundtable notes. Group has AI to begin
documenting all of these failed parts and begin submitting info to ABB.
FYI - The consensus was that, during overhaul, this should be inspected.
ABB recommends that if found, replace.
Do not add Anderol 757 or MG28 to the outside (exterior) of this Inner Spring
Tube during assembly. If found to have lubricant, then it will need to be
removed (part replaced if coating is missing).
FYI
Waterford, TMI, TVA, and PSEG
If rivet can be moved by hand, the entire latch should be replaced per ABB.
If not loose, no need to replace. New Trip Latches have welded reset spring
return pin.
Part 21 issued on 12-2-99 to inspect and replace. Bad batches from back to
1995 due to improper material and/or not heat treated.
Mark McClelland: HK problem with failing to close…assumed hand
switch…operator issue possibly. Traced problem to L2 switch in another
cubicle. Spring clip had come off. Suggests PI might have permissive
circuitry problem. PI has verified signal to secondary disconnect.
Intermittent problem.
References
2005 CBUG Meeting Notes
HK Roundtable Issues
1998 HK CBUG Meeting Notes
2000 HK CBUG Powerpoint
EPRI "Evaluation of Cracks in ABB HK Arc Chutes"
Rev 0 dated 11/13/02.
2001 ABB T&D Discussion Items HK
2001 ABB T&D Discussion Items HK
2004 CBUG Meeting Notes, Notes from HK Utility
Roundtable
EPRI "Evaluation of Cracks in ABB HK Arc Chutes"
Rev 0 dated 11/13/02.
2004 CBUG Meeting Notes, Notes from HK Utility
Roundtable
EPRI "Evaluation of Cracks in ABB HK Arc Chutes"
Rev 0 dated 11/13/02.
2008 CBUG ABB HK Roundtable Notes
2009 CBUG ABB HK Roundtable Notes
2002 ABB Discussion Items HK
2003 CBUG Powerpoint Presentation
2003 CBUG Meeting Notes
2004 CBUG Meeting Notes, Notes from HK Utility
Roundtable
2004 CBUG Meeting Notes, Notes from HK Utility
Roundtable
2004 CBUG Meeting Notes, OE 16527
2004 CBUG Meeting Notes, OE 16739
2004 CBUG Meeting Notes, OE 17451
2008 CBUG HK Meeting Notes
OE 25399 - Perry - 8/2007
2005 CBUG Meeting Notes
ABB Presentation: EPRI Action / Discussion Items
HK Circuit Breakers (cont.)
2006 CBUG Powerpoint Presentation
2007 CBUG Powerpoint Presentation (Modified
2007 by D. Hatfield)
2005 CBUG Meeting Notes
HK Roundtable Issues
2001 ABB T&D Discussion Items HK
2001 ABB T&D Discussion Items HK
2004 CBUG Meeting Notes, Notes from HK Utility
Roundtable
2004 CBUG Meeting Notes, OE 16879
2008 CBUG HK Meeting Notes
OE 24754 - Prairie Island - 4/2007
OE 25640 (Update to OE 24754)
2000 HK CBUG Powerpoint
2004 CBUG Meeting Notes, Notes from HK Utility
Roundtable
2004 CBUG Meeting Notes, Notes from HK Utility
Roundtable
2005 CBUG Meeting Notes
Remaining HK Breaker OE NOT Previously
Addressed in the ABB Presentation: EPRI Action /
Discussion Items HK Circuit Breakers
2005 CBUG Meeting Notes
HK Roundtable Issues
2004 CBUG Meeting Notes, Notes from HK Utility
Roundtable
2001 ABB T&D Discussion Items HK
2005 CBUG Meeting Notes
HK Roundtable Issues
2008 CBUG ABB HK Roundtable Notes
2004 CBUG Meeting Notes, OE 16764
2001 ABB T&D Discussion Items HK
2009 CBUG Handout (reissued)
ABB IB 6.2.1.7B Supplement (5/31/00)
2009 CBUG Handout (reissued)
ABB IB 6.2.1.7B Supplement (5/31/00)
2000 HK CBUG Powerpoint
2001 ABB T&D Discussion Items HK
2003 CBUG Meeting Notes
2003 CBUG Meeting Notes
2004 CBUG Meeting Notes, OE 16387
2004 CBUG Meeting Notes, OE 18438
2008 CBUG HK Meeting Notes
OE 25535 - Prairie Island - 8/2007
2008 CBUG HK Meeting Notes
OE 25990 - McGuire - 11/2007
2005 CBUG Meeting Notes
HK Roundtable Issues
2005 CBUG Meeting Notes
ABB Presentation: EPRI Action / Discussion Items
HK Circuit Breakers
2005 CBUG Meeting Notes
ABB Presentation: EPRI Action / Discussion Items
HK Circuit Breakers (cont.)
2005 CBUG Meeting Notes
ABB Presentation: EPRI Action / Discussion Items
HK Circuit Breakers (cont.)
2005 CBUG Meeting Notes
Remaining HK Breaker OE NOT Previously
Addressed in the ABB Presentation: EPRI Action /
Discussion Items HK Circuit Breakers
1999 HK CBUG Meeting Notes
2002 CBUG Meeting Notes
2003 NMAC "No Intentional Opening" Powerpoint
Presentation
2004 CBUG Meeting Notes, Notes from HK Utility
Roundtable
2009 CBUG Handout
2004 CBUG Meeting Notes, OE 18435
1998 HK CBUG Meeting Notes
2003 CBUG Meeting Notes
2005 CBUG Meeting Notes
Remaining HK Breaker OE NOT Previously
Addressed in the ABB Presentation: EPRI Action /
Discussion Items HK Circuit Breakers
1999 HK CBUG Issue Notes
2001 CBUG Meeting Notes
2004 CBUG Meeting Notes, OE 17213
2004 CBUG Meeting Notes, OE 17906
2005 CBUG Info collected on HK Primary Stabs
Powerpoint - ABB (CBTS) Action / Discussion Items
for Type HK Switchgear Maintenance (Part of
Powerpoint)
2005 CBUG Info collected on HK Primary Stabs
Powerpoint - ABB (CBTS) Action / Discussion Items
for Type HK Switchgear Maintenance (Part of
Powerpoint)
2003 CBUG Meeting Notes
EPRI TR-109642
EPRI 1003087 (Mobil28 Evaluation)
EPRI TR-109642
2003 CBUG Meeting Notes
2008 CBUG ABB HK Roundtable Notes
2005 CBUG Meeting Notes
HK Roundtable Issues
2004 CBUG Meeting Notes, OE 17796
2005 CBUG Meeting Notes
ABB Presentation: EPRI Action / Discussion Items
HK Circuit Breakers (cont.)
2004 CBUG Meeting Notes, Notes from HK Utility
Roundtable
2008 CBUG HK Meeting Notes
OE 25341 - San Onofre - 7/2007
2007 CBUG Meeting Notes
OE24048
2004 CBUG Meeting Notes, Notes from HK Utility
Roundtable
2004 CBUG Meeting Notes, OE 17374
2009 CBUG HK Meeting Notes
OE 28777 - Comanche Peak - 3/2009
2006 CBUG Presentation
2009 CBUG HK Meeting Notes
OE27451 - Vogtle - 8/2008
2001 CBUG Meeting Notes
2002 CBUG Meeting Notes
1998 HK CBUG Meeting Notes
2001 ABB T&D Discussion Items HK
2004 CBUG Meeting Notes, Notes from HK Utility
Roundtable
2009 CBUG Handout (reissued)
2003 CBUG Meeting Notes
2003 CBUG Meeting Notes
ABB MS 3.2.1.9-1
EPRI TR-109642
EPRI TR-109642
EPRI TR-109642
2005 CBUG Info collected on HK Primary Stabs
Powerpoint - Waukesha (Gene Langlois)
2005 CBUG Info collected on HK Primary Stabs
Powerpoint - ABB (CBTS) Action / Discussion Items
for Type HK Switchgear Maintenance (Part of
Powerpoint)
2007 CBUG Meeting Notes
2006 CBUG Powerpoint Presentation
2005 CBUG Meeting Notes
HK Roundtable Issues
2003 CBUG Meeting Notes
2004 CBUG Meeting Notes, Notes from HK Utility
Roundtable
2008 CBUG HK Meeting Notes
OE 26649 - Sequoyah - 3/2008
ABB MS 3.2.1.9-1
EPRI NP-7410-V2P1 Sec 4.0
2008 CBUG ABB HK Roundtable Notes
2009 CBUG ABB HK Roundtable Notes
2009 CBUG ABB HK Roundtable Notes
2008 CBUG ABB HK Roundtable Notes
2009 CBUG Handout (reissued)
1998 HK CBUG Meeting Notes
1998 HK CBUG Meeting Notes
EPRI TR-112814 (Reduced Cnl Voltage Testing)
2003 CBUG Meeting Notes
2006 CBUG Powerpoint Presentation
2003 CBUG Powerpoint Presentation
2003 CBUG Powerpoint Presentation
2003 CBUG Powerpoint Presentation
2003 CBUG Powerpoint Presentation
2003 CBUG Powerpoint Presentation
2002 CBUG Powerpoint
2002 ABB Discussion Items HK
2005 CBUG Powerpoint & Failure Analysis
Presentation
2002 ABB Discussion Items HK
2003 CBUG Meeting Notes
OE 15980 - North Anna - 4/2003
2004 CBUG Meeting Notes, Notes from HK Utility
Roundtable
2009 CBUG HK Meeting Notes
OE 28125 - Perry - 12/2008
2005 CBUG Info collected on HK Primary Stabs
ABB (Hatfield) response to EPRI email request
(07/01/03) for information (Sharkey) on HK Primary
Stab Maintenance
2005 CBUG Info collected on HK Primary Stabs
ABB (Hatfield) response to EPRI email request
(07/01/03) for information (Sharkey) on HK Primary
Stab Maintenance (cont.)
2005 CBUG Info collected on HK Primary Stabs
Paper on Prairie Island Nuclear Generating Plant 4kV Switchgear Events Following the 3 August 2001
Bus Fire
2005 CBUG Meeting Notes
ABB Presentation: EPRI Action / Discussion Items
HK Circuit Breakers (cont.)
2005 CBUG Meeting Notes
ABB Presentation: EPRI Action / Discussion Items
HK Circuit Breakers (cont.)
2009 CBUG HK Meeting Notes
OE 28220 - San Onofre - 11/2008
2002 CBUG Meeting Notes
2005 CBUG Meeting Notes
Remaining HK Breaker OE NOT Previously
Addressed in the ABB Presentation: EPRI Action /
Discussion Items HK Circuit Breakers
2005 CBUG Meeting Notes
HK Roundtable Issues
2007 CBUG Handout
2005 CBUG Meeting Notes
ABB Presentation: EPRI Action / Discussion Items
HK Circuit Breakers (cont.)
ALSO DISCUSSED IN 2005 HK ROUNDTABLE
2003 CBUG Powerpoint Presentation
2008 CBUG ABB HK Roundtable Notes
2005 CBUG Meeting Notes
ABB Presentation: EPRI Action / Discussion Items
HK Circuit Breakers (cont.)
2004 CBUG Meeting Notes, Notes from HK Utility
Roundtable
2007 CBUG Powerpoint Presentation
OE22305 OE22346
2002 CBUG Meeting Notes
2008 CBUG ABB HK Roundtable Notes
2005 CBUG Meeting Notes
ABB Presentation: EPRI Action / Discussion Items
HK Circuit Breakers (cont.)
2004 CBUG Meeting Notes, Notes from HK Utility
Roundtable
2006 CBUG Presentation of failure report
2004 CBUG Meeting Notes, OE 16633
1998 HK CBUG Meeting Notes
2001 ABB T&D Discussion Items HK
1998 HK CBUG Meeting Notes
2002 ABB HK S-G Part Rplcmnt Speadsheet
2003 CBUG Meeting Notes
2003 CBUG Document
2003 CBUG Meeting Notes
2003 CBUG Meeting Notes
2004 CBUG Meeting Notes, Notes from HK Utility
Roundtable
2009 CBUG HK Meeting Notes
03/11/2009
(NCR #68999JL)
2009 CBUG ABB HK Roundtable Notes
2004 CBUG Meeting Notes, Notes from HK Utility
Roundtable
2005 CBUG Meeting Notes
HK Roundtable Issues
2001 CBUG Meeting Notes
2005 CBUG Meeting Notes
ABB Product & Service Information Bulletin Notice
2005-2-0002
2002 Duke Breaker Survey Spreadsheet
2003 CBUG Round Table
1999 HK CBUG Meeting Notes
2001 ABB T&D Discussion Items HK
1999 HK CBUG Meeting Notes
2000 HK CBUG Powerpoint
2004 CBUG Meeting Notes, Notes from HK Utility
Roundtable