ML20113G253

Application for Amend to Licenses NPF-11 & NPF-18,revising Tech Specs to Correct Kw Capacity for Voltage Variation in Standby Gas Treatment Sys Duct Heater.Fee Paid

ML20113G253
Person / Time
Site:	LaSalle
Issue date:	01/15/1985
From:	Rybak B COMMONWEALTH EDISON CO.
To:	Harold Denton Office of Nuclear Reactor Regulation
Shared Package
ML20113G256	List: ML20113G253 ML20113G280
References
9625N, NUDOCS 8501240295
Download: ML20113G253 (4)

Text

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[  % Commonwealth Edison

7) ons First N*tionit Plats. Chicago lilinois

\ C ?] AC' dress Reply to: Post Offica Box 767

\ g Cr icago. Illinois 60690 January 15, 1985 Mr. Harold R. Denton, Diractor Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, DC 20555

Subject:

LaSalle County Station Units 1 and 2 Proposed Technical Specification Change Clarification of Standby Gas Treatment Heater Rating NRC Docket Nos. 50-373 and 50-374

Dear Mr. Denton:

Pursuant to 10 CFR 50.59 Commonwealth Edison proposes a change to the Technical Specifications for LaSalle County Station Units 1 and 2. The proposed change now specifies the kW capacity be correciad for voltage variation for the SBGTS duct heater when it is tested. The current Technical Specifications do not specify any voltage rating and therefore allows for some ambiguity in interpretation. This ambiguity was discovered upon testing of the new EQEE' qualified duct heaters for the Standby Gas Treatment System.

The intent of the specification is to determine if the duct

-heater performance has degraded. Identification of the rated voltage -value of 480 volts in conjunction with changing the kW capacity to the value at rated voltage for the new heaters and allowing a 10 percent variance in kW capacity meets the intent of the existing technical specifications. This is consistent with the existing technical specification for the SBGTS heater which identifies the capacity as 20 kW + 2 kW (i.e., 10%) at 460 volts, the rated voltage for a 20 kW heaYer.

We have reviewed this proposed change, in general, with members of your staff and Region III personnel who agree that this change is consistent with the original bases for the Technical Specification.- Therefore, this clarifying amendment is being submitted as an administrative change.

A discussion of the basis of the proposed amendments is provided in Attachment 1. The proposed changes have received On-Site and Off-Site review and approval and are enclosed in Attachment 2. We have reviewed these amendment requests and find that no significant hazard consideration exists. Our review is-documented in Attachment 3. \

8501240295 850115 DR ADOCK 05000373 \

PDR _ _

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e H. R. Denton January 15, 1985 Pursuant to 10 CFR 170, a fee remittance of $150.00 has been enclosed.

Commonwealth Edison is notifying the State of Illinois of our request for these amendments by transmittal of a copy of this letter and its attachments to the designated State Of ficial.

Please address any questions you may have concerning this matter to this office.

Three (3) signed originals and thirty-seven (37) copies of this transmittal are being provided for NRC review.

Very truly yours, AG.

B. Ry Nuclear Licensing Administrator 1m cc:. -J. . Keppler - Region III M. Parker - IDNS Resident Inspector - LSCS Attachments

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. SUBSCRIBED AND SWORN to

' before me' this - /SA:(day

-of k sucas u,, , 1985

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~ . Notary Public-M$(b 9625N-if

e ATTACHMENT-1 BASIS FOR-PROPOSED TECHNICAL' SPECIFICATION-CHANGE REQUEST LASALLE COUNTY UNITS-1 AND

SUBJECT:

- Standby Gas 1 Treatment Duct Heater Surveillance Requirement

-REFERENCES (1): FSAR Section 6.5.1.2.1.c.4.

(2): N510-1975, Testing of Nuclear Air-Cleaning System BACKGROUNO-The duct' heaters for the Standby Gas Treatment System are designed to' reduce ~the; relative humidity of the airflow to a maximum of 70%

RH at-the' worst inlet: conditions. A 20_kW single stage heater was

- originally installed to provide this function (Reference 1). These

. heaters are-provided with surveillance requirements to ensure they provide-their design function..

DISCUSSION The TechnicalLSpecifications and_ Reference 2 provide surveillance

, requirements to. ensure that these heaters perform their design 1 function.- . Reference 2 requirements'are covered in Section 14 of

~

that" document.. The Technical Specification requirements are~ covered

' in-FSAR Section 6.5.1.2.1.c.4. The duct heater is sized to provide a= minimum of 47,000 BTU /hr at 958F inlet temperature. There is no maximum size heater limit as described in the FSAR. However, Technical Specification 4.6.5.3.d.3_ requires that the heater

. maintain 20 kW + 2 kW. The acceptance : range is provided to ensure that heater degradation'is_ detected. The requirement of Reference 2 Lto maintainfa 5% difference between phases will.also detect a l potential failure 1of the -heater. The proposed specification will still require.this standard to be followed and the acceptance range

, to be; maintained, however, the heater: rating is raised to 23 kW at

480V. .In addition, due;to variations in bus voltage, the + 2 kW

.cannot be maintained for all:possible supply voltages. The

. variations in. bus voltage are maintained within design limits but-the' restriction of + 2 KW canLonly apply when the heater power

. dissipation'is corrected for bus voltage-variations. -.The diesel.

generator. loading.is:not significantly effected by.the 3 KW increase in.the heater rating. In addition the possible increase-in heater downstream temperature due to the-increased limit is acceptable as 1

L the.' system'would need to see greater than 88 kW' input before the

-thermal' cutoff' setting of 220cF is reached.

_ __ J: 4 A. . + .# -- - R ATTACHMENT 2 PROPOSED CHANGE TO

. ;. . TECHNICAL SPECIFICATION LASALLE COUNTY STATION UNITS 1 and 2 UNIT-1 Revised Pages: .3/4 6-41 UNIT 2 Revised Pages: ~ 3/4 6-44 f

I r-L9625N

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