ML20151G753
| ML20151G753 | |
| Person / Time | |
|---|---|
| Site: | Seabrook  |
| Issue date: | 07/22/1988 |
| From: | Glowacky T PUBLIC SERVICE CO. OF NEW HAMPSHIRE |
| To: | |
| Shared Package | |
| ML20151G732 | List: |
| References | |
| OL-1, NUDOCS 8807290206 | |
| Download: ML20151G753 (6) | |
Text
--
O l
UNITED STATES OF AMERICA UNITED STATES NUCLEAR REGULATORY COMMISSION l
l before the ATOMIC SAFETY AND LICENSING BOARD
)
In the Matter of
)
)
PUBLIC SERVICE COMPANY
)
Docket Nos.
50-443 OL-1 NEW HAMPSHIRE, et al.
)
50-444 OL-1
)
'(Seabrook Station, Units 1
)
(On-site Emergency and 2)
)
Planning Issues)
)
AFFIDAVIT OF THOMAS W. GLOWACKY I. THOMAS W. CLOWACKY, being on oath, depose and say as follows:
1.
I am employed by Yankee Atomic Electric Company as a Senior Engineer in the Seabrook Project Electrical Engineering Group.
A state-ment of my professional qualifications is attached and marked as "A".
2.
I performed an evaluation of all the applications of ITT Surprenant RG-58 coaxial cable at Seabrook Station.
The purpose of this evaluation was to assure that the failure of these nonsafety-related cables under postulated environmental conditions will not prevent satis-f actory accomplishment of saf ety f unctions by safety-related equipment during low power testing. This evaluation is necessary because RG-58 cables are routed by design with other safety-related and nonsafety-related cables in Train A instrumentation ("V") level raceways.
3.
Due to postulated environmental conditions, the RG-58 cables are assumed to fail worst case such that the center conductor and outer shield short together.
Assuming a f ailure of this nature, the potential for over-heating and ignition of the RG-58 cable and potential thermal degradation j
8807290206 880722
)
PDR ALOCK 050'CX)443 Q
of adjacent safety-related cables were evaluated taking into consideration the available fault energy (current' levels).
4.
This evaluation addressed all 126 (Reference Affidavit of Richard Bergeron dated June 16, 1988 at 1 3)'RG-58 cables.
It should be noted thet 12 of these cables, (all of those which were routed in a harsh environment within 'the nuclear island), have since been replaced witn qualified RG-59 coaxial cable.
5.
The 126 RG-58 cables can be grouped into the following categories by application:
Category No. of Cables 1
(1) Main Plant Computer System data link 40 between Intelligent Remote Termination Unit (IRTU) and computer (2) Main Plant Computer System output to' 39 CRT Monitors, for color 1
(3) Keyboard Logic output to Main Plant 11 Computer System (4) Spare cables for Category (1) above and 21 1
1 miscellaneous spare cable (5) Ultrasonic Level Detectors for the Waste 14 j
l Processing, Chemical and Volume Control, and Boron Recovery Systems (6) Core Menitor for the Turbine Generator 1
126 The functions of all of the above applications are nonsafety-related.
This was determined based on my review of the electrical schematic drawing packages wherein the safety designation of each circuit is identified.
Also, the cable code (TA6Y) assigned to RG-58 coaxial cable indicates that the cable color is black with a red tracer, which indicates a nonsafety-related Train A application routed in Train A, Channel I in-,
strumentation ("V" level). raceways.
See FSAR Sections 8.3.1.3 and
- 8. 3.1.4 and FS AR Figure 0. 3-5 7.
6.
A review of the circuits for each of these applications was pe rf o rmed. -This included review of plant drawings, discussions with plant staff and equipment manufacturers, and review of manufacturer's data sheets for various electronic devices.
7.
Based on this review, the device used to drive the output in each circuit application utilizing RG-58 cable was identified.
In each of these applications the output devices were found to be either Integrated Circuits (IC) or discrete transistor circuits.
Of all the devices identified, the device with the highest output cur'ent was rated at 400 milliamperes (400 x 10-3 amperes) on a non-continuous basis (50 milliseconds on/l second off).
This should be compared with normal operating currents of 100 mil 11 amperes or less.
All of these devices by nature of their construction are low energy devices and are inherently current limiting. When subjected to short circuit failures, such as those postulated, some devices enter a current limit mode due to internal protection, while others will try to supply greater than rated current.
Operation.of these devices in excess of their rated currents and power dissipation levels will lead to failure of the devices.
Typical failure nodes are melting of the substrate material and the internal bonding connections associated with the ICs and transistors which subsequently leads to interruption of the circuit.
Since, as discussed in Paragraph 8, the equivalent rated ampacity of an RG-58 cable is 8-10 amperes, failure of the device and circuit interruption will occur long before there would be any affect on the cable.
8.
Coaxial cable is not typically assigned a rated ampacity. The cable impedance, capacitance, attenuation, and velocity of propagation are the properties normally considered when applying coaxial cables.
These properties and the construction of coaxial cable, i.e., cente r conductor with a shield, make it uniquc froc cables used in power and control applications.
Coaxial cable by nature of these unique properties is generally used in low level signal (voltage & current) instrumentation and data transmission applications.
In the Seabrook Station design, RG-58 cable is only used for these applications.
To evaluate the effects of the current levels identified for the specific applications at Seabrook on the RG-58 cable and adjacent cables, a comparison must be made with an equivalent rated ampacity for the RG-58 cable. The RG-58 center conductor size is #21 AVG.
Based on standard ampacity tables, a single conductor cable of this size has an ampacity in the range of 8-10 amperes. This ampacity is dependent on the conductor insulation tempera-ture rating.
Comparison of this typical ampacity rating with the maximum current available (i.e., 4i mil 11 amperes) for the various RG-58 cable applications shows that the cables are applied well within their ampacity rating, such that the cables will not overheat.
9.
In addition, a test (Reference Af fidavit-of Randy C. Jamison at i 2-7) was performed to evaluate the temperature rise of the RG-58 cable when subjected to the 400 mil 11 amperes maximum credible current.
For conservatism, a test current of 1 ampere was utilized for the test.
The test results' demonstrated that the RG-58 ca' ale is capable of carrying this current without causing degradation of ad,dacent cables.
10.
In conclusion, the evaluation that v'es performed indicates that sufficient fault energy does not exist in the circuits evaluated..
to cause overheating of the RG-58 cables and subsequent thermal degradation of adjacent cables. The failure (i.e., short to ground) of any nonsafety-related RG-58 coaxial cables, addressed by this evalatuion, due to postulated environmental conditions does not pose any challenge to any safety-related circuits, and, therefore, the ability for safe plant shutdown under post-ulated design base accident conditions during low power testing has not been jeopardized.
M l'
Thomas W. Glowacky STATE OF NEW HAMPSHIRE Rockingham, ss.
July 22, 1988 The above-subscribed Thomas W. Glowacky appeared before me and made oath that he had read the foregoing affidavit and that the statements set forth therein are true to the best of his knowledge.
1 Before me, w m d>-s b. $ $ b eu, Beverly E. Ei.)loway, Notary Public My Commission Expires: March 6, 1990 t
"A" THOMAS W. GLOWACKY SENIOR ENGINEER EDUCATION BS Electrical Engineering, New Jersey Institute of Technology (formerly Newark College of Engineering), 1978 In 1978, he joined W. R. Grace Company, Polyfibron Division, as a Systems Engineer, supervising field installations.
He later transferred within W. R. Grace Company to their Daramic Battery Separator Plant, as a Process Engineer.
In 1982, he joined the Electrical Engineering Group of Yankee Atomic Electric Company as an Engineer.
In this capacity he has performed engineering studies, design changes and reviews for the Yankee Plant, Vermont Yankee, Maine Yankee and Seabrook Station.
In his present position as Senior Engineer, he is responsible for performing various activites within the electrical engineering discipline on Seabrook Project. These activities include preparation of design changes, calculations, and technical evaluations.
. - - -