ML19347C045

Submits Addl Info Requested in NRC Re Adequacy of Facility Electric Distribution Sys Voltages

ML19347C045
Person / Time
Site:	La Crosse File:Dairyland Power Cooperative icon.png
Issue date:	09/17/1980
From:	Linder F DAIRYLAND POWER COOPERATIVE
To:	Crutchfield D Office of Nuclear Reactor Regulation
References
LAC-7160, NUDOCS 8010160507
Download: ML19347C045 (4)

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DA/RYLAND

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OOPERA T/VE no nox air. ms rAST AV SOUm. t A CROSSE WSCONSIN M601 160m 7884c00 j

September 17, 1980 In reply, please refer to LAC-7160 DOCKET NO. 50-409 Director of Nuclear Reactor Regulation 4

I ATTN:

Mr. Dennis M. Crutchfield, Chief l

Operating Reactors Branch #5 j

Division of Operating Reactors j

U.

S. Nuclear Regulatory Commission l

Washington, D. C.

20555 j

SUBJECT:

DAIRYLAND POWER COOPERATIVE LA CROSSE BOILING WATER REACTOR (LACBWR)

PROVISIONAL OPERATING LICENSE NO. DPR-45 l

ADEQUACY OF STATION ELECTRIC DISTRIBUTION SYSTEM VOLTAGE FOR THE LA CROSSE BOILING WATER REACTOR

References:

(1)

NRC Letter, Gammill to All Power Reactor Licensees, dated August 8, 1979.

(2)

DPC Letter, Linder to Ziemann, LAC-6719, dated January 2, 1980.

(3)

DPC Letter, Linder to Gammill, LAC-6822, dated March 13, 1980.

(4)

DPC Letter, Linder to Gammill, LAC-6912, dated May 12, 1980.

l (5)

NRC Letter, Crutchfield to Linder, dated June 27, 1980.

Gentlemen:

Your letter (Reference 5) requested additional information on the adequacy of station electric distribution system voltages.

Responses to your questions are as follows.

NRC OUESTION #1 Page 2, paragraph 3" requires that "the adequacy of the oncite distribution of pove from the offeite circuito chatt be verified by test to acaure that analysis results are valid. "

Reference d did not verify the adequacy of the analysis for Class 1E buses in A t tach-ment 8.

This should be done as this revicu is to deternine the adequacy of the voltage of the equipment on these busec.

DPC RESPONSE:

Attachment " A" shows the measured values of the bus voltage at the 480V level and measured loads in amperes at the Class lE buses.

These measurements were conducted by DPC on August 18, 1980. 8010160507

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Mr. Dennis M. Crutchfield, Chief LAC-7160 Operating Reactors Branch #5 September 17, 1980 This attachment further shows the calculated values of bus vo1> ace at 480V Essential Bus IA, 480V Essential Bus 1B, 480V Turbine Building MCC 1A, and Reactor Building MCC 1A for the loading shown.

A comparison between measured and calculated values of the bus voltage at 480V level indicates that the differences are well within the metering accuracy errors.

It is, therefore, concluded that the results of the analysis are valid for Class lE buses also as demonstrated by the close agreement between the measured and calculated values.

NRC QUESTION H2 Supply the calculated voltages for all lou-voltage AC (less 'han 180V) class 1E buses (including the alternate cource for the static inverter) for each analyzed case.

Do these systens supply any in-struments or control circuits as required by GDC 13?

If co, is all the equipment capable of sus taining the analyned voltages without l

blouing fusca, overheating, etc., and uithout affecting the equip-ment 's ability to perform the rcquired function?

DPC RESPONSE:

The instruments and control circuits as required by GDC-13 are powered by instrument buses normally supplied by the inverter and alternate feed is through SOLA voltage regulators which control voltages from 96 to 132.

NRC OUESTION H3 There are no identified technical specificatione restricting the use of the following bus interties:

480V bus 1A to bus 1B; 480V ESS bus 1A to bus 1B.

Per NRC guideline 1G, the use of these bus intertiec must be analyzed for the vorst poccible loading condition.

DPC RESPONSE:

These buses have never been tied together except during cold shut-down for a short maintenance period.

NRC QUESTION #4 0

Sargint & Lundy recommended that the tap for the Reserve Auxiliary trancformer be changed from the 72450 V setting to the 70725 V tap, and provided analyais that shous (vith above exceptione) that use of this lover tap is satisfactory (uhile original tap is not).

DPC, in references b or c, did not commit to making this tap change.

DPC should either make this tap change or justify why it icn't changed.

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Mr. Dennis M. Crutchfield, Chief LAC-7160 Operating Reactors Branch #5 September 17, 1980 DPC RESPONSE:

A Facility Change has been submitted to change the tap setting for the Reserve Auxiliary Transformer from 72450 V to the 70725 V tap.

..This will be accomplished as soon as operational conditions permit.

If there are any ques *. ions regarding this rasponse, please contact us.

Very truly yours, DAIRYLAND POWER COOPERATIVE r

wvb ruw Frank Linder, General Manager FL:WRN:af Att.

cc:

J.

Keppler, Rcg. Dir., NRC-DRO III NRC Resident Inspectors i

I i

3-

l j,gaggg Calm Justifi -

j Value lated Error cation Vahm

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69 kV Generator I U

Bet UAM Trt:

NW 724 X

3=

m 5F Non-Seg Bus Duct Imped = 0.000462

+J0.004629 2400" Bus 1 A

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-c Cable Imped

=0.001354

+J0.0008592 l

1 480V TR#1A w u 2520-480V m m 750/1000 kVA Z=5.4% @ 750 kVA Bus Volt 445 445 480V Bus lA 4

.003792 +

~'

J.0021770 72A y

Sbterina Bus Volt 441 444.68

.839 Inaccu-"

480V ESS Bus lA racy

.0051 +

J.00llG 72A l

5bterurt Bus Volt 440 444.33

.98% Inaccu-Turb. Blda. MCC 1A racy I

LACBWR GENERATIN#

VERIFICATION OF ANALY 480V CLASS lE BD l

ATTACHMENT A

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Calcu-

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w eg yg Justifi-Value r

on Value SS srve Aux, asf. 01 50-2400V 7% @ 5 MVA VA (OA) 2400V Bus 1B Cable Imped

=0.001083

+J0.0006870 480V TR#1B 2520-480V wss m m 750/1000 kVA i

Z=5.4% @ 750 t0V Bus 1B kVA Bus Volt 442 442

.001491 +

92A J.0022180 V

Meterin!

480V ESS Bus 1B Bus Volt 437 4! 41.77 1.091 Inaccu-g racy

.0122 +

84A J.00370 l

V

%eterim Rx Bldg. MCC 1A

' Bus Volt 437 440.74 0.85% Inaccu-racy UNIT M Y TEST 3ES l

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