ML20093E106
| ML20093E106 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 06/28/1984 |
| From: | Daltroff S PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | Murley T NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| References | |
| IEB-84-02, IEB-84-2, NUDOCS 8407170377 | |
| Download: ML20093E106 (8) | |
Text
{{#Wiki_filter:4 e. i PHILADELPHIA ELECTRIC COMPANY 2301 M ARKET STREET P.O. BOX 8699 PHILADELPHIA. PA.191o1 SHIELDS L DALTROFF .Jflic",'.U'"Jio. June 28, 1984 Docket Nos. 50-277 50-278 Dr. Thomas E. Murley Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Region I 631 Park Avenue King of Prussia, PA 19406
SUBJECT:
Information Relative to I.E. Bulletin 84-02, entitled, " Failures of General Electric Type HFA Relays in Use in Class lE Safety Systems"
Dear Dr. Murley:
I.E. Bulletin No. 84-02 concerning " Failures of General Electric Type HFA Relays in Use in Class lE Safety Systems", dated March 12, 1984, required that actions be taken by all holders of operating licenses. The actions are restated below along with responses for Peach Bottom Unit 2 and Unit 3. Request la: 1. Plants in Operation a. Develop plans and schedules for replacing (1) nylon or Lexan coil spool-type HFA relays used in normally energized safety-related applications and (2) nylon coil spool-type HFA relays used in normally de-energized safety-related applications. The replacement relays and any replacements made in the future should meet the requirements of the applicable IEEE standards. The replacement program for energized and de-energized relays should be performed on a "best efforts" basis 8407170377 840628 PDR ADOCK 05000277 G pon \\\\ 16 y
..= -.. t' z, lDr. Thomac E. Murley. Juns 28, 1984 Page 2 during plant outages of sufficient duration. The entire replacement program'should be completed within two years from the date of this bulletin. L The' replacement schedule should consider the following recommended' priority: A. Nylon or Lexan normally energized in the i reactor trip system. B. Nylon or Lexan normally energized in the other l safety-related applications. j C. Nylon normalli de-energized in'the reactor i l trip system. ) D. Nylon normally de-energized in other safety- !~ related applications. 5 ] Response la There'are 723 HFA Relays used in the Reactor Protection la. ) System and other safety-related'3ystems on Peach Bottom 'l Units 2 & 3.. Of these relays, 710 are.the older type relays that have Lexan or Nylon spools. It is planned-to replace all the HFA relay coils (464), that fall into the above 4 priority categories, with new Century Series coils or relays. The replacement coils and relays have been determined to be qualified for their i-intended service. We had previously initiated a-4 modification to replace all Nylon and Lexan 115 Vac HFA 1 1 coils in the Reactor Protection System and the Primary i Containment Isolation System.. Replacement coils are j available on site to start this portion of the replacement program. The following plans apply to each of the four priority categories, i l .TsC. Century Series coils are available to replace all i of these coils, except for two' relays on each unit.. These relays will: be replaced due to coil unavailability. The work is planned to be completed on Unit:2 during'the present' refueling i outage and~on Unit 3 during the next refueling outage,.whichuis planned to start April 1985. This work. involves 70 replacements on Unit 2'and 81 replacements on Unit 3.
l j 1 'Dr. Thomas E. Murley-June 28, 1984 Page 3 t B. Century Series coils are available to replace normally energized 115 Vac coils used in the-other safety-related applications. The work is planned to be completed on Unit 2 during the present L refueling outage and on Unit 3 during the next refueling outage, which is planned to start April i 1985.. This work involves 49 replacements on Unit f. 2 and 53 replacements on Unit 3. ~ } Century Series coils are being purchased to i replace the normally energized-125 Vdc HFA coils in the other safety-related applications. These 4 coils will be installed on Unit 2 during the ) present refuel outage or during next outage of j sufficient duration depending on the date of the i receipt'of-the new coils. The coils on Unit 3 i will be replaced during the next. refueling outage. This work involses 22 replacements on Unit 2 and ( 22 replacements on Unit 3. 1 D. Century Series coils are available to. replace all .the normally de-energized nylon 115 Vac coils used in other safety-related applications. The work is l 7 planned to be completed on Unit 2 during the j present refueling outage. This work involves 3-j replacements on Unit 2. 1 l Century Seriec coils are'being. purchased to replace all'the normally.de-energized nylon 125 l Vdc coils in the other-safety-related systems. j These coils will~ be installed on Unit 2 during the present refuel. outage or during next-outage.of sufficient-duration depending'on the.date of the i receipt of-the new coils. The coils on Unit 3' L will be replaced during the next.refuleing outage. i. This work involves :ll5 replacements on Unit 2.and 49 replacements on Unit 3 and common equipment. j. Request lb(1): 1 j lb. During the period before relay replacement, develop and implement' surveillance plans that include: i 4 ~l (1) Monthly functional tests of-all-reactor trip system normally energized relays that' verify relay f contacts change state when.the relay: coil 11;s de-energized. I
June 28, 1984 Dr.. Thomas E. Murley Page 4 Response 1b(ll: There are 62 reactor protection system (RPS) normally energized HFA relays in each of Peach Bottom Unit 2 and Unit
- 3.. Prior to the issuance of this bulletin, 54 of these relays in each unit were being functionally tested at least once a month, with 20 of these relays in each unit being functionally tested once a week.
There are 4 HFA normally in (Neutron Monitoring Noncoincident Trips) energized relays the RPS which do not require a functional test because the relays' contacts are no longer used and had been jumpered out of the logic during a previous codification. As a result of this bulletin, four additional surveillance tests (ST ll.10A, B, C, D) were written to functionally test the 4 remaining RPS normally energized HFA relays once per These new surveillance tests.were' reviewed and month. approved by the Plant Operational Review Committee. On May 3, 1984, the four new surveillance tests were used.to functionally test the four remaining relays in question on Peach Bottom Unit 3. Unit 2 was removed from service on April 28, 1984, to start its 6th refueling outage, and therefore the four relays in question on Unit 2 were not functionally tested because the relays will be replaced during the refuel outage. As required by the bulletin, all of the above mentioned surveillance tests functionally verify that the' relay contacts change state when the relay coils are de-energized. Request,1bj2): lb. During the period before relay replacement, develop and implement surveillance plans that-include: visual inspections of all safety-related.normally (2) energized relays as soon as practical upon receipt of this bulletin. Thereafter, similar inspections-should. be accomplished in conjunction with the monthly functional test. These-visual inspections should verify that relay coils are not deteriorating (e.g., inspect ' coil bobbins for visible cracks or melting), and should confirm cleanliness of.the relay pole pieces. I J } l 1
._ ~. Dr.' Thomas E; Murley June 28, 1984 Page 5 4 Response _lb (2)_: Prior to the' issuance of this bulletin, during the last Unit 3 refueling outage, all Unit 3 HFA relays were visually inspected. Upon the receipt of'this bulletin, PECo field engineers performed a visual inspection of all normally energized HFA relays in Unit 2. Using a routine test (:RT 2.2), written as a result of this bulletin, a visual inspection of all safety-related normally energized Unit 3 i HFA relays was performed on May 10, 1984. This RT includes 2 - normally energized relays.in RPS, PCIS, HPCI, RCIC, 4kV sw itchge ar, ADS, and the recirculation system. This RT will be performed monthly on Unit 3.until the relays are replaced. Unit 2 was removed from service on April 28, 1984, to start its 6th refueling outage; and therefore, the 4 routine test (RT 2.2) for visual inspection of normally energized HFA relays is not required since these relays will be replaced during the refueling outage, As specified in the bulletin, the visual inspections require j inspection of coil bobbins for visible cracks and/or melting j~ and confirm cleanliness of the relay pole pieces. 4 4 Request lc: j Ic. Provide a basis for continuing operation for the period of time until the normally energized relays are l, replaced. This basis should include a discussion of those measures addressed in Items la and lb and any 4 J-other preventive and/or corrective measures taken or planned. .i f Response lc: f ic. - During the past several years,.there has been a developing pattern of end-of-life coil failures in our I 115 Vac normally energized HFA relays. This,patternfof ) failures has existed only on Unit 2, which is now shut down for refueling. None of the failures have j prevented the relays from performing their safety function. It is expected that all Nylon and Lexan 115 . Vac relay coils in Unit 2 safety-related systems will be replaced before Unit 2 returns to power. Plans are underway to replace-125-Vdc relay coils in Unit _2 as indicated in Response la above. 1 4 -.2 m
) 4. Dr. Thomas E. Murley' Juna 28, 1984 Page 6 I At the present time, there has not been any indication of end-of-life coil failures on Unit 3 HFA relays. .Since the end-of-life coil failures on Unit 2 have been occurring on the 115 Vac normally energized relays, the previously addressed surveillance tests and monthly i inspections on these Unit 3 relays will provide additional assurance for their correct. operation. Therefore, the present condition of the Unit 3 relays will allow safe operation of the Unit until. the relay coils are replaced in 1985. i Request 2: Although the specific details involving the identified relay l failures described.above may not directly apply to your facility (ies), you are asked to review the general concerns l expressed in the bulletin for applicability at your facility (ies). For example, if a different type of relay is i used for the same safety functions described in this j bulletin, or relays with similar materials are used for other safety-related functions, past operating history and the manufacturer's recommendations should be reviewed to i determine if additional action is appropriate. Your i response should describe the results of the review, and, if the general concerns apply, you should describe the short-i term and long-term corrective actions to be taken and the schedules thereof. l' L Response _2 i Although HFA relays are used extensively in the Reactor i Protection System and other safety-related systems'in the plant, we have compiled a list of the approximately 25 various types of additional relays used in safety systems in L order'to check for applicability of this bulletin. We are reviewing these types of relays to determine if materials similar to those in the HFA relays are used or-if there are manufacturer's recommendations _regarding replacement. Our i review and evaluation of these additional relays is ~ incomplete at this time; however, a-review of past operating history indicates that no short-term corrective actions are necessary. When our evaluation is complete, we.will provide ~ a summary of the'results. We will provide additional I ) corrective actions and' replacement schedules if it is'found necessary to replace additional relays. The review is expected to be complete by September 30, 1984. k1 g ~ f c.---- .,..w y ,-w ,-,s, r-.- ---r-p, < - - -e
Dr. Thomas E. Murley June 28, 1984 Page 7 Request 3: The written report required shall be submitted to the appropriate Regional Administrator under oath or affirmation under provisions of Section 182a, Atomic Energy Act of 1954, as amended. Response 3: An appropriate affidavit is attached. If you require any further information, please do not hesitate to contact us. Very truly yours, e[~ ./ _ tf W Attachment cc: A. R. Blough, site Inspector Document Control Desk '" d '*' 's 'I L. 5: 3;: NAl..I,,,. i 1
Attachment.1 Docket Nos. 50-277 50-278 COMMONWEALTH OF PENNSYLVANIA : ss, i COUNTY OF PHILADELPHIA S. L. Daltroff, being first duly sworn, deposes and says. That he is Vice President of Philadelphia Electric Company; that he has read the foregoing response to I.E. Bulletin 84-02 relative to Peach Bottom Units 2 and 3 and knows the contents thereoft and that the statements and matters set forth therein are true and correct to the best of his knowledge, information and belief. / g/7 / gr - -{----- g Subscribed and sworn to d before me this.29 day of W NI s WllAd QQ Notary Public JUOtTH Y. PMANetLIN ' Notary PubHC Phita., Phile. Co. My Commission Empires July 28,1987 -}}