ML20086T176
| ML20086T176 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley, Peach Bottom, Point Beach  |
| Issue date: | 07/19/1995 |
| From: | Dahle C, Hinch H, Martin J ASEA BROWN BOVERI, INC. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| REF-PT21-95 NUDOCS 9508020264 | |
| Download: ML20086T176 (4) | |
Text
_
ABB e
July 19,1995 Page 1 Document Control Desk US Nuclear Regulatory Commission Washington, D.C.
20555
SUBJECT:
ABB Relays, Type 51's and 87T Defective Tap Block (10CFR Part 21 Report)
NOTIFICATION BY:
ABB Power T&D Company Protective Relay Division 7036 Snowdrift Road Allentown, PA 18106 Harry A Hinch Quality Assurance The ABB Relays are electronic protective relays used in electrical switchgear.
The ABB Distribution Relay Division is issuing this Part 21 Report to advise its customers of a potential problem with type 51's and 87T relays. This problem is limited to type 51 relays catalog number series 443/423/223 and type 87T relay catalog number series 419T / 219T manufactured during the 5/1/94 through 6/15/95 time period.
The potential problem has been identified as a defective Tap Block, ABB part number 609224-001, this part is a seven (7) position tap block located on the upper transformer printed circuit board. This part is used to change the relay's current settings.
The tap block is designed to revert to the highest tap rating when j
the tap pin is removed. A small percentage (.0025) of these tap blocks were found to be defective from our supplier, when the tap pin is removed the tap block will open circuit the transformer circuit.
The transformer circuit is externally wired to the systems current Transformers. When the CT's are open circuited a large voltage potential is possible creating a potential hazard to the operator.
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,. e July 19,1995 Page 2 The Attachment 1 page identifies the relay types, catalog numbers, customers, serial numbers, purchase order numbers and sales order numbers of the relays containing suspect defective Tap Blocks. ABB Relay Division Allentown will notify all. the end users who purchased these Relays ABB recommends that all users identified on the Attachment #1 page verify by testing per the instruction listed on the enclosed Product Advisory Letter, PAL 95-108
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Prepared by Harry'Hindr 9'
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QA supervi'sor Reviewed by u
ad Ja k Martin P
duct Line Manager Reviewed by 3
Cheryl Dahle i
Manager, Total Quality l
l Reviewed by Robert Sm'iTh
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Site Manager I
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Attachment #1 PAL 95-108
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l Page 1 s
July 18,1995 l
l Nuclear Service Customer List l
Type Qty Catolog #
S.O.
P.O.
Customer End User Serial No,s 51E 2
443T3340 BRK1059 252943 Wisconsin Power Point Beach 59044 & 59045 51Y 3
443S2341 BLB1254 BW696206-NO PECO Peach Bottom 60062 thur 60064 51L 12 443T5540 PIT 8327 D136598 Duquense Light Beaver Valley 60493 thru 60504 S1IM 4
443T8540 PIT 8327 D136598 Duquense Light Beaver Valley 60505 thru 60508 1
u,.
Agg PAL 95-108 5/31/95 Product Advisory Letter - Relay Type 51's and 87T The ABB Distribution Relay Division is issuing this Product Advisory Letter ( PAL 95 - 108 ) to advise its customers of a potential problem with type 51's and 87T relays. This problem is limited to type 51 relays catalog number series 443/423/223 and type 87T relays catalog number series 419T/ 219T manufactured during the 5/1/94 through 6/15/95 time period. This Product Advisory Letter will be issued to customers who have purchased the above type relays that could have this potential prcblem. All units involved are covered under our warranty.
The potential problem has been identified as a defective tap block, ABB part number 609224 001, this part is a seven (7) position tap block located on the upper transformer printed circuit board. This part is used to select or change the relay's current settings.
The tap block is designed to revert to the highest tap rating when the tap pin is removed. A small percentage (.0025) of these tap blocks were found to be defective from our supplier, when the tap pin is removed the tap block will open circuit the transformer circuit.
The transformer circuit is extemally wired to the systems Current Transformers. When the CT's are open circuited a large voltage potential is possible creating a hazard to the operator.
All suspect relays should be tested or checked during the next scheduled routine maintenance.
Warninz:
Customers should not attempt to change the tap pin location while the units are energized.
Open circuitinyhe CT's presents a potentialfor serious injury or death.
The relay can be checked after removing it from service by measuring the impedance at the connection in the rear of the CT board.
On single phase overcurrent units Cat # XXXSXXXX remove the tap pin from the front of the unit and check for continuity between terminal #3 and #4. If continuity is present the tap block is working correctly. If there is no continuity notify the factory immediately and do not retum the unit to senice.
On three phase overcurrent units Cat # XXX.T_/PXXXX remove the tap pins from the front of the unit and check for continuity between terminals #1 and #2, #3 and #4, and #5 and #6. If continuity is present the tap block, in that Phase, is working correctly. If there is no continuity notify the factory immediately and do not return the unit to senice On Transformer Differential relays Cat # 419T/FXXXX remove the tap pins from the front of the unit and check for continuity between terminals #1 and #2, #5 and #6, and (#3 and #4, three (3) winding unit only ) If continuity is present the tap block is working correctly. If there is no continuity notify the factory immediately and do not return the unit to senice For those who find defective tap block in their relays and wish to retum their relays to the factory for the component change, please contact the Repair Department at the Relay Division in Allentown, Pa. 1-800-634-6005 or 610-395-7333 to make the necessary arrangements. The component change will be made at no charge until 6/97. Questions regarding this PAL should be directed to Harry Hinch, QA Supenisor, at the above listed numbers.
ABB PowerT & D Company Inc.
Telephone:
Distdbution Relay DMslon tax::
610-395-7333
~ 7036 Snowddft Road. Suite 2 610-395-1055 Allentown. PA 18106