ML18096A506
| ML18096A506 | |
| Person / Time | |
|---|---|
| Site: | Salem  |
| Issue date: | 01/31/1992 |
| From: | Labruna S Public Service Enterprise Group |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML18096A507 | List: |
| References | |
| REF-GTECI-048, REF-GTECI-049, REF-GTECI-NI, TASK-048, TASK-049, TASK-48, TASK-49, TASK-OR GL-91-11, NLR-N92006, NUDOCS 9202100324 | |
| Download: ML18096A506 (5) | |
Text
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Public Service Electric and Gas Company Stanley LaBruna Public Service Electric and Gas Company P.O. Box 236, Hancocks Bridge, NJ 08038 609-339-1200 Vice President - Nuclear Operations JAN 3 t 1992 NLR-N92006 United States Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 Gentlemen:
RESPONSE TO GENERIC LETTER 91-11 GENERIC ISSUE 48, "LCOs FOR CLASS IE VITAL INSTRUMENT BUSES" GENERIC ISSUE 49, "INTERLOCKS AND LCOs FOR CLASS IE TIE BREAKERS" SALEM GENERATING STATION UNIT NOS. 1 AND 2 FACILITY OPERATING LICENSE NOS. DPR-70 AND DPR-75 DOCKET NOS. 50-272 AND 50-311 Generic Letter 91-11 requests each operating reactor licensee to ensure its plant has procedures, including time limitations and*
surveillance requirements, for:
- 1)
Vital instrument buses (typically 120 V ac buses),
- 2)
Inverters or other onsite power sources to the vital instrument buses; and
- 3)
Tie breakers that can connect redundant Class lE buses (ac or de) at one unit or that can connect Class lE buses between units at the same site.
For plants without procedures covering each of the above, the Generic Letter requests an evaluation justifying the.licensee's position.
The following is Salem Generating Station's response to Generic Letter 91-11.
Generic Issue 48, "LCOs for Class lE Vital Instrument Buses" Salem Unit 1 and 2 each have four 115 V AC vital instrument buses (VIB's).
Normal 230V AC, alternate 230V AC and 125V DC vital power is supplied to each of the VIB's as follows:
A B
c D
---~
;:;-4<r0131 92021000 30c~ 05000212 PDR A
PDR p
Power Supply A.
B c
B f)tJ;J7 I I !I
Document Control Desk NLR-N92006 *
-JAN 3 1 1992 The higher voltage vital AC distribution systems consist of three independent trains (e.g., 4.16 kv vital buses A, Band C).
Therefore, VIB "D" does not have a unique power supply, and is fed from the "B" vital bus.
There is no "D" Emergency Diesel Generator or Safeguards Equipment Controller (load sequencer).
VIB's A, B and C Salem Unit 1 and 2 Technical Specifications Section 3/4.8.2 (attached), and implementing procedures, establish the operability and surveillance requirements for the A, B and c vital AC power distribution systems.
Specification 3/4.8.2.1 addresses Modes 1 through 4 (Power Operation through Hot Shutdown), while Specification 3/4.8.2.2 addresses Modes 5 and 6 (Cold Shutdown and Refueling).
With the exception of Unit 1 Specification 3.8.2.2, the Limiting Conditions for Operation include the inverters as part of the VIB's.
The difference between the Unit 1 and Unit 2 Technical Specifications reflects the fact that Unit 1 was licensed prior to Unit 2 (i.e., to earlier standard Technical Specification requirements).
However, the operability requirements as defined by the surveillance procedures are identical for both units, and include verification of inverter operability at least once per 7 days.
The inverters are operable if they maintain output voltage and frequency within the appropriate values, and if the proper alignment is verified per the surveillance procedure (using checklists to verify required indicating light status, breaker position and switch position).
Proper inverter alignment ensures the capability to transfer to the DC power supply if normal AC is lost.
VIB 110 11 Because there are no "D" vital 230V, 480V or 4160 Volt AC buses, VIB "D" is not included in the Technical Specifications for either Salem Unit.
It is therefore not subject to the LCO's and surveillance requirements of VIB A, B and C.
VIB "D" is required to be energized to support operability of the equipment to which it supplies power (e.g., instrumentation channels).
Operation of the vital instrument inverters, including "D", is governed by procedure OP IV-4.3.1, "Vital Instrument Bus Inverter Operation."
Although no allowed outage times are imposed on the "D" inverter, the procedure ensures the proper operation of the inverter, including the appropriate precautions, status verification in the control room, and restoration to its normal configuration.
This procedure is used_ following preventive maintenance (during refueling outages), and in response to inverter trouble (as required by alarm response procedures).
Document Control Desk NLR-N92006
- Abnormal Operating Procedures (AOP's) are in place to address loss of each of the Vital Instrument Buses (ie., four AOP's per Salem Unit).
These AOP's include an identification of the effects of the deenergized bus on the individual components affected, as well as alternate indication and/or control capability.
These procedures have been revised as part of the Salem Procedure Upgrade Project, and were approved in January 1992.
Generic Issue 49, "Interlocks and LCOs for Class lE Tie Breakers" Salem Generating Station utilizes Class lE tie breakers for vital DC power systems.
Vital DC power operability (including breaker alignment) is verified by procedure, once per 7 days in accordance with Technical Specifications 3/4.8.2.3 through 3/4.8.2.6 (attached).
Vital DC distribution systems utilize mechanically interlocked tie breakers to prevent simultaneous closure of cross-connected breakers.
In addition, breaker alignment for vital DC power supplies is controlled by procedure OP IV-5.3.3, "DC Breakers - Administrative Control."
This procedure addresses the possibility of failure of the mechanically interlocked tie breakers (i.e., fire induced fusing of two interlocked breakers in close proximity to each other).
Emergency feed breakers at the vital DC switchgears are maintained open, so that a short circuit across a mechanically interlocked tie breaker would not result in loss of redundant vital trains.
As part of the Salem Radiation Monitoring System (RMS) Project (i.e., Design Change Package 2SC-2229, which is being installed during the present Unit 2 outage), the 120 V AC RMS power supplies are being modified.
The modification includes the installation of maintenance tie breakers.
New procedures have been developed to control the use of the RMS power supply breakers.
These procedures will be used upon completion of the RMS design change, and will ensure proper system configuration to maintain channel independence.
There are no other tie breakers for vital AC power distribution systems at Salem Generating Station.
Please feel free to contact us if there are any questions regarding this transmittal.
Attachment Affidavit Sincerely,
Document Control Desk NLR-N92006 C
Mr. J. C. Stone Licensing Project Manager Mr. T. Johnson Senior Resident Inspector Mr. T. Martin, Administrator Region I Mr. Kent Tosch, Chief New Jersey Department of Environmental Protection Division of Environmental Quality Bureau of Nuclear Engineering CN 415 Trenton, NJ 08625 JAN 3 1 1992
STATE OF NEW JERSEY
)
REF: NLR-N92006 GL 91-11
)
SS.
COUNTY OF SALEM
)
Stanley LaBruna, being duly sworn according to law deposes and says:
I am Vice President - Nuclear Operations of Public Service Electric and Gas Company, and as such, I find the matters set forth in our letter dated
- JAN 3 1 1992
, concerning the Salem Generating Station, Unit Nos. 1 and 2, are true to the best of my knowledge, information and belief.
Subscribed and Sworn to before me this 3/
day ofr
-f J,, ",.kiL ~- ~
1992 Notary~lic of ~w Jersey My Commission expire~ on ELliABETH J. KIDD Notary Public of New Jersey My Commission Expires April 25, 1995
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