ML20080D727
| ML20080D727 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 08/25/1983 |
| From: | Hukill H GENERAL PUBLIC UTILITIES CORP. |
| To: | Stolz J Office of Nuclear Reactor Regulation |
| References | |
| RTR-NUREG-0737, RTR-NUREG-737, TASK-2.F.2, TASK-TM 5211-83-230, NUDOCS 8308300561 | |
| Download: ML20080D727 (5) | |
Text
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Nuclear
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Route 441 South Middletown, Pennsylvania 17057 0191 717 944 7621 TELEX 84 2386 Writer's Direct Dial Number:
August 25, 1983 5211-83-230 Office of Nuclear Reactor Regulation Attn:
J. F. Stolz, Chief Operating Reactor Branch No. 4 Division of Licensing U.S. Nuclear Regulatory Commission Washington, D.C.
20555
Dear Sir:
Three Mile Island Nuclear Station, Unit 1 (TMI-1)
Operating License No. DPR-50 Docket No. 50-289 Inadequate Core Cooling (NUREG 0737, II.F.2)
Your letter of June 14, 1983 requested clarification on two items of minor concern dealing with the Subcooling Margin Monitor.
The first item related to our letter of March 10, 1983 (83-071) and the surveillance requirements for the SMM.
Amendment 78 dated October 20, 1982, p. 4.7a (attached) provides those requirements. Surveillance Procedure 1302.-6.6, available on site, discusses specific details of that surveillance. Additionally, pages 6 and 7 of attachment 1 to our letter of March,1983 have been revised for the sake of readability and are enclosed.
The second item concerned our letter of February 18, 1983 (83-039) and the seismic qualification of the SFDi indicator. GPUN has recently contacted Westinghouse and Combustion Engineering concerning a qualified digital indicator. We are advised that these two vendors do not provide an indicator qualified separately from the entire instrumentation package. These indica-tors are also not compatible with existing instrumentation at TMI-1.
(GPUN's SFD! was designed and partially installed prior to the time that these NSSS vendors were developing a SFDI instrumentation package). However, GPUN has contacted another vendor who is currently qualifying a digital indicator.
Upon receipt of successful results, GPUN will place an order for this indicator which is compatible with our SMM system.
8308300561 830825 DR ADOCK 05000289 PDR GPU Nuclear Corporation is a subsidiary of the General Public Utilities Corporation n
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Mr. J. F. Stolz 5211-83-230 Additional information requested in Attachment 1 of your June 14 letter will be provided as further detailed design information becomes available.
Sincerely, i.
D.
Iukill Director, TMI-l
!!Dil:DiH:vj f Attachments cc:
R. Conte J. Van Vliet
- 'y.
DESIGN AND QUALIFICATION OF THE SATURATION MARGIN MONITOR 1, Environmental / Seismic Qualification - The pressure measurement is obtained i
from 2 seismic and environmentally qualified sensors.
The temperature mea surement is control grade, and all signals are seismic Category I and separated for use as redundant signals.
The qualification of the meter was recently discussed in our letter of February 14, 19fs3.
- 2. Single Failure - Redundant channels which are electrically independent are used.
- 3. Power Sources - The two saturation margin monitors use separate power supplies (115 Vac 60 Hz) powered from safety grade inverters.
4, Availability - The operability / surveillance requirements of the saturation margin monitor are provided in Amendment 78 dated October 20,19,82.
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- 5. QA Requirements - The quality level of all equipment covered for the saturation margin monitor is designated as Uuclear Safety Related, Class 1E and meets the requirements of the OQA plan Rev. 9.
The temperature sensors, plant computer and announciation system are nonsafety related components.
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- 6. Continuous Operation - The saturation margin monitor will continuously
~isplay the margin between actual primary coolant temperature and the d
saturation temperature.
- 7. Recording Instrumentation - Outputs of saturation margin are provided for trending and alarm annoutciation by the plant computer.,
- 8. Dispisy Instrumentation
, Digital display of the margin between actual RCS temperature and saturation temperature for the existing RCS pressure is provided in the control room on the back panel (PCL).
- 9. Isolation - The Tsat computation equipment provides isolation to the pressure and temperature signals through the use of isolation devices at the signal inputs. The Tsat outputs to the announciation system and the computer utilize isolation devices to minimize potential hazardous effects from these system.
- 10. _T_e s tina - Te s t signals may be substituted for normal RC pressure and temperature signals to verify operation on the Tsat Margin Monitor equipment. Operating checks can be performed by reading RC pressure and temperature and with calculations obtain the Tsat margin.
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- 11. Surveillance - See item 4.,
e 32, Re=cval Free Service - The Tsat Margin Menitor is designed such that all necessary functicnal tests can be performed en line without affecting other reac t or ' sys tems. Any testing that is required to be performed offline shall not be required to be performed at less than 15 month intervals.
- 13. Access for Adjustment_ - The Tsat Margin Montiers are rack meunted in signal processing channel A and B equipment cabinets.
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cabinets is the same as for normal maintenance.
Accessibility for these 14, _Anetalcus Reading - Anomalous readings are reduced to a minicum by items 2, 3 and 7.
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- 15. Ease of Repair - See item 13.
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- 16. Directiv Measured Variable Sensors - RCS te=perature and pressure sensors provide direct inputs to the saturat'.cn cargin calculation.
)7* Hor =al/ Accident Ranges - The Tsat Margin Monitor has a range of l
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-100' to 400'F which is suitable for nor=al and accident conditions.
- 18. Periodic Testing - Testing is described in item 10 and surveillance vill be provided as discussac in item 11.
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TART,E 4.1-1 ntinued) 1 DIANNEl. DESCRIPTION glECK TEST CAI.IBRATE REMARKS N 49. Saturation Margin Monitor S(1)
M(1)
R (1) When ave is greater than 525*F.
N
- 50. Emmergency Feedwater Flow NA H(1)
R (1) When ave is greater than 250*F.
g Instrunnentation
- 51. Emergency Feedwater Initiation a.
Loos of RCP's NA Q(1)(2)
R (1) Wisen ave is greater than 250*F.
b.
Loss of both Feedwater NA Q(1)(2)
R (2) Includes logic test only Pumpe Oh:
H 7
O u
c-r TT 5 - Each Shift T/W - Twice per week R - Each Refueling Period p - paily B/M - Every 2 siontles NA - Not neplicalile I
W - Weekly Q - Quarterly R/W - Every two wecks M - Mont hly P - I'rlor to encle startiop if not done prestoun week N
N
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