Part 21 Report - 1995-013
ACCESSION #: 9502160190
Nutherm
INTERNATIONAL, INC.
501 SOUTH ELEVENTH STREET/MT. VERNON, ILLINOIS 62864/
(618) 244-6000/FAX (618) 244-6641
November 7, 1994
Tennessee Valley Authority
Browns Ferry Nuclear Station
P.O. Box 2000
Decatur, AL 35602-2000
Attention: Ms. Claudia Dyar
Subject: Capacitors Installed in HDR Converters
Dear Ms. Dyar:
Nutherm is in the process of investigating the aforemention subject. In
the intrim the following is in regard to the question about the capacitors
in the 3KVA inverters purchased under your P.O. No. 87NLF839263. HDR's
service Bulletin No. 009 addresses 3300 MFD capacitors (P.N. 0133235)
which are present in your units (circuit designation C1, C5).
A visual inspection needs to be made to determine if the units contain
these capacitors with date codes between 8630 and 8850. The date codes
are located on the last line of markings on the capacitors. Other signs
to look for are bulging sides on the caps or leakage from the weep holes.
If the capacitors are suspect, a test can be performed to check for low
capacitance. Depress and release the precharge button and note the time
it takes for the bleeder resistors to discharge the cap bank after the
button is released. The voltage should bleed off slowly. If a rapid
decrease in voltage is noted the capacitors should be replaced.
The most common failure caused by one of these capacitors being faulty is
blowing one of the DC input fuses (FU1, FU2).
After your completion of the inspection please contact Nutherm with the
results. If you have any further questions please do not hesitate to call
me at (618) 244-6000.
Sincerely,
NUTHERM INTERNATIONAL, INC.
Lawrence Patterson
Director of Compliance
LP/kh
FL:C:\TVA
ATTACHMENT 2 QA-1-95-1003
Page 1 of 3
Nutherm
INTERNATIONAL, INC.
501 SOUTH ELEVENTH STREET/MT. VERNON, ILLINOIS 62864/
(618) 244-6000/FAX (618) 244-6641
November 10, 1994 QA-11-94-985
Bechtel Power Corporation
9901 Washingtonian Boulevard
Gaithersburg, MD 20878-5356
Attention: V. R. Marathe, Electrical Control System Engineering Chief
Subject: Capacitors Installed In HDR Converters
Dear Mr. Marathe:
Nutherm is in the process of investigating the aforementioned subject.
In the interim the following is in regard to the question about the
capacitors in the 5KVA inverters purchased under your P.D. No. 18691-E-
554. HDR's Service Bulletin No. 009, Rev. 1.1, dated 2/19/92 addresses
3300 MFD capacitors (P.N. 0133235) which may be present in your units.
A visual inspection needs to be made to determine if the units contain
these capacitors with date codes between 8630 and 8850. The date codes
are located on the last line of markings an the capacitors. Other signs
to look for are bulging sides on the caps or leakage from the weep holes.
If the capacitors are suspect, a test can be performed to check for low
capacitance. Depress and release the precharge button and note the time
it takes for the bleeder resistors to discharge the cap bank after the
button is released. The voltage should bleed off slowly. If a rapid
decrease in voltage is noted, the capacitors should be replaced.
The most common failure caused by one of these capacitors being faulty is
blowing one of the DC input fuses (FU1, FU2).
Page 1 of 2
ATTACHMENT 2 QA-1-95-1003
Page 2 of 3
Bechtel Power Corporation
Attn: V. R. Marathe
QA-11-94-985
Page 2 of 2
After your completion of the inspection, please contact Nutherm with the
results. If you have any further questions please contact me at (618) 244-
6000.
Sincerely,
NUTHERM INTERNATIONAL, INC.
Fran Starr
Manager
Quality Assurance
cc: Connecticut Yankee Power Station
Northeast Utilities
Attn: QA Mgr.
362 Injun Hollow Road
East Hampton, CT 06424-3093
BPC-2552 QA File
BPC-2552 Job File
FS:fs
ATTACHMENT 2 QA-1-95-1003
Page 3 of 3
Nutherm
INTERNATIONAL, INC.
501 SOUTH ELEVENTH STREET/MT. VERNON, ILLINOIS 62864/
(618) 244-6000/FAX (618) 244-6641
PART 21 INITIAL NOTIFICATION QA-1-95-1003
January 20, 1995
Page 1 of 2
I. Fran Starr, Manager - Quality Assurance
Nutherm International, Inc.
501 South 11th. Street
Mt. Vernon, IL 62864
II. 3300 MFD capacitors, P.N. 0133235, contained in 3KVA and 5KVA HDR
Inverters supplied to Tennessee Valley Authority (TVA) Browns Ferry
Nuclear Plant and Northeast Utilities Connecticut Yankee Power
Station via Bechtel Power Corporation. Installation/system
locations are unknown.
III. The 3300 MFD capacitors, P.N. 0133235, were manufactured by
Mepco/Centralab and are contained in the HDR Inverters. The
Inverters were qualified and supplied by Nutherm International,
Inc., 501 South 11th. Street, Mt. Vernon, IL
IV. The defective capacitors, which were manufactured between the 30th
week of 1986 and the 50th week of 1988, exhibit low or no
capacitance when failed. The most common failure caused by one of
these capacitors being faulty is blowing one of the DC input fuses
(FU1, FU2); thereby, rendering the HDR Inverter from performing its
design function.
V. Nutherm was notified by TVA on 10/21/94 and copy of HDR Service
Bulletin, Rev. 1.1, dated 2/19/92 was faxed by TVA to Nutherm on
10/21/94 (Attachment 1).
VI. The HDR Inverters that may contain the defective capacitors were
supplied by Nutherm to Tennessee Valley Authority (TVA) and Bechtel
Power Corporation as follows:
(1) TVA - Browns Ferry Nuclear Plant, Purchase Order No:
87NLF839263, Item No: 1, Quantity two (2), 3KVA Inverters
Nutherm Reference No: TVA-2649
(2) Bechtel Power - Northeast Utilities Connecticut Yankee Power
Station, Purchase Order No: 18691-E-554, Item 2.1, Quantity
two (2), 5KVA Inverters, Nutherm Reference No: BPC-2552
PART 21 INITIAL NOTIFICATION QA-1-95-1003
January 20, 1995
Page 2 of 2
VII. Corrective action included a request to TVA and Bechtel/Northeast
Utilities to perform a visual inspection and contact Nutherm with
the results in order to determine if defective capacitors were
installed in the HDR Inverters (Attachment 2).
VIII. Nutherm recommended that TVA and Northeast Utilities inspect the
installed capacitors and if the inspection disclosed the installed
capacitors to be suspect, replace the suspect capacitors in order
to assure that they do not affect the operation of the facility to
which they were supplied.
HDR Uninterruptible
Power Systems
BULLETIN # 009
REVISION # 1.1
PAGE # 1
REV. DATE: 2/19/92
SERVICE BULLETIN
DATE: JANUARY 11, 1991 GENERATED BY: FIELD SERVICE APPROVED BY: DON
IMLAY
SUBJECT: DC CAPACITOR BANK
MODELS AFFECTED: ALL HIGH DC UNITS (MFR'D BETWEEN JUNE 1986 AND JUNE
1989)
IMPLEMENTATION DATE: DECEMBER 27, 1990
IMPLEMENTATION LEVEL: AS NECESSARY
DC capacitors manufactured by Mepco/Centralab (3300 MFD 350V, P.N.
0133235) between the 30th week of 1986, and the 50th week of 1988, have
been showing a defect that results in low or no capacitance when failed.
They may or may not leak.
These grey jacketed caps display the date code on the last line of
markings on the cap. (Ex: 8646 - 46th week of 1986). To check for low
capacitance, note the time it takes for the bleeder resistors to discharge
the cap bank after the precharge button is released.
Contact the factory for assistance if the DC cap bank contains the above
mentioned capacitors. HDR's phone number is: 614-771-5500 or fax number:
614-771-7219.
DISTRIBUTION: MANUFACTURING, FINAL TEST, FIELD SERVICE, 3RD PARTY
SERVICE CO.
ATTACHMENT 1 QA-1-95-1003
Page 1 of 1
*** END OF DOCUMENT ***
Page Last Reviewed/Updated Wednesday, March 24, 2021
Page Last Reviewed/Updated Wednesday, March 24, 2021