ML20207C807

Forwards Outline & Results of First Fault Isolation Test for Fischer & Porter 50EK1000 I/I Converter Which Verified Fault Current Did Not Affect Input Circuit,Per 861211 Telcon.Ltr Transmitted Second Test Results

ML20207C807
Person / Time
Site:	Davis Besse
Issue date:	12/23/1986
From:	Williams J TOLEDO EDISON CO.
To:	Stolz J Office of Nuclear Reactor Regulation
References
1337, TAC-57033, NUDOCS 8612300244
Download: ML20207C807 (5)

Text

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TOLEDO EDISON Docket No. 50-346 JOE WituAMs. JR.

Scrwr vwe F%awa twe l41'3J 249 2300 License No. NPF-3 141912a ma Serial No. 1337 December 23, 1986 Director of Nuclear Reactor Regulation Attention: John F. Stolz PWR Project Directorate No. 6 Division of PWR Licensing-B United States Nuclear Regulatory Commission Washington, D. C. 20555

Dear Mr. Stolz:

On December 11, 1986, a phone call was held between representatives of the NRC and Toledo Edison regarding isolation devices between the Safety Parameter Display System (SPDS) and the other safety systems at Davis-Besse Nuclear Power Station Unit No. 1. This call concerned our October 3, 1986 letter (Serial No. 1309) which transmitted the requested test data on the Fisher & Porter 50EK 1000 Converter. The Staff inquired about cortain aspects of the test data. We explained that the test results submitted were from the second test that was performed on the isolation device.

The first test was performed at Davis-Besse in accordance with the test outline attached. The fault current was appl.ed for three (3) minutes.

Total time that the isolation device was energized was approximately 45 minutes. This was also the same isolation device that was used in the second test discussed in the letter referenced above. Attached is a copy of the test outline and results for the first test which verified that the fault current did not affect the input circuit, and that the isolation device continued to perform its function.

Very t ruly yours, h/

J : GAB:pif Attachment cc: DB-1 NRC Resident Inspector 8612300244 861223 l, a/

PDR ADOCK 05000346 Q4 p PDR me maoo me- c- mso- xo -oso-- mmoo - o - ,b

. Docket No. 50-346 Licen o No..NPF-3 S2 rial No. 1337 Attachment FAULT ISOLATION TEST FOR FISCHER AND PORTER 50EK1000 I/I CONVERTER 1.0 PURPOSE To apply a fault current transversely across the output terminals of the I/I Converter, to verify the fault will not affect the 1E input of the device.

2.0 EQUIPMENT REQUIRED 2.1 50EK1000, Fisher and Porter I/I Converter, CCC Pt. NO. KD978, 4-20 mA input and output, 118 VAC power.

2.2 Variac 0-135 VAC output, 120 VAC input. Equip No A CalDue9I 2.3 24 VDC power supply or battery. Equip No yc 3. T 2 4 Cal Due ues 2.4 2K OHM 1.0% Resistor.

1 2.5 1-SPST Switch, Hook-up Wire.

2.6 1 OHM 0.01% Resistor, or G_e_neral Radio Decade Resistance Box.

Equip No_-fc. J. tog Cal Due ncR

_ 2.7 1 Gould Brush 6 Channel Recorder. Equip No TC3. f.2d'al Due pc.R F.0TE: Additional measuring equipment may be required if this recorder does not provide sufficient resolution to C observe a change of 0.1 MV.

C 2.8 Fluke Model 8600 Multimeter, Set on 200 m A Scale. Equip No T C 3. l. g_9 O Cal Due 7. /B. B ra_

2.9 Additional device (as required, see Figure 1 NOTE)

Name: FM sr. o D Equip No re J.1 4 i Cal Due S / O - 8J.

Additional Equip Required: he h JM A, MMb W 0 '

3.0 LIMITS AND PRECAUTIONS I ok AuJfn. -

3.1 Since a considerable amount of heat can be generated during this test, do not touch any components, once circuit is energized.

3.2 Since it is possible for failed components to cause physical damage, the test setup should be shielded or physically removed from test personnel in order to avoid injury.

e: -

t Docket.Na. 50-346

, Licsnse No. NPF-3 S; rial Ns. 1337 4.0 TEST BASIS 4.1 The 50EK1000 contains an internal resistor which will limit current in output (faulted) circuit to about 0.1 AMP. For this reason, the only overcurrent protection provided for the fault current circuit-is the 10 AMP, fuse which is part of the variac. Should the variac fuse open, indicating current through the converter is not being limited, this test will be revised to increase the current capability of the fault current device. The branch circuits to the SFAS are supplied by 30 AMP breakers and are limited to 15 AMPS by fuses, which is the maximum credible fault. Since no limit is placed upon fault circuit externally, the only limit is imposed for test circuit protection and does not in any way compromise this test.

4.2 Once the fault current is introduced, input circuit current will be measured to determine the current change caused by the faulted condi-tion.

4.3 Allowable converter change is based upon converter tolerance (0.25%)

'I plus allowable setpoint value margin to Tech Spec Reportable Value.

7or example, if typical trip bistable was set at the extreme value

' Juring the monthly surveillance test, a fault would not cause the value to change enough to create a condition outside of Tech Spec Allowable e3 value.

ge, EXAMPLE:

.. 1. Converter Tolerance = 0.25% of 16 mA span = 0.04 mA

,, 2. CTMT press 18.4 PSIA trip is adjusted in ST 5031.01, and must between 8.50 and 8.78

__ mA. Tech Spec Reportable Value is 8.86 mA.

Therefore, worst case allowable deviation

"' = 0.08 mA is 8.86 mA - 8.78 mA C? Total Allowable Input Deviation = 0.12 mA (1. + 2.)

C This is 0.75% of Span for I/I Converter 4.4 The time for application of fault will be approximately one minute.

This time is sufficient to obtain meaningful data, and is long enough to exclude transient effects; and yet long enough to reach an equi-librium condition. Current will be monitored to ensure steady state conditions are achieved. If changes are observed, test will continue until steady-state conditions are observed.

5.0 PREREQUISITES 5.1 Connect test setup per Figure 1.

i 5.2 With 51 switch open, adjust variac. to provide 120 VAC output.

5.3 Energize 1/I Converter and 24 VDC power supply.

5.4 Label recorder charts and ensure operation of all inputs.

5.5 Run converter for at least 1/2 hour before continuing with test. g g,gg

Dockgt Na. 50-346 -

3-

'Lic0nra No. NPF-3 S: rial No. 1337 Attachment 6.0 PROCEDURE 6.1 Run recorder at 125 mm/ min.

6.2 Close S1 switch and mark with event marker start of test.

6.3 After data has been obtained for at least one minute, record input current from ammeter. If current is changing continue to apply fault current until steady-state is achieved.

G 7. k A FAULT CURRENT 6.4 Open S1, then de-energize circuit.

6.5 From recorder chart or from alternate measurement device, record input current (recorder Channel 2) before and after S1 is closed.

NOTE: Current during fault condition should be at time of about one minute into test.

df . 4Lf" mA at end of test (prior to Sl opening) e' eq d@. sF 4L mA at beginning of test (prior to S1 closing)

C. O l mA current change 7.0 ACCEPTANCE CRITERIA 7.1 Current change from non-faulted to faulted condition does not change

.-. I/I input current by more then 0.12 mA.

E.)

CD L'D

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Docket No. 50-346 41 celt L No. NPF-3 Serini No. 1337

' Attachment FIGURE 1:

Test setup for fault isolation test on SFAS I/I Converter

{ (applied fault in transverse mode).

FISCHER & PORTER 50EK1000 I/I CONVERTER LINE VOLTAGE 120 VAC SUPPLY L2 b'

,3 4 ,

x -

0 OUTPUT SI

+

{ 120 VAC

% TO RECORDER O CHANNEL 1 t "-

Q INPUT B

( - [ -

1 24 VDC

- 1 OHM 2K OHM MmM-C C

C o o o a, CH 2 CH 3 TO RECORDER Connect to Brush recorder (this is a guide, final connection by field).

CH I  :~20V/DIV. 0-200V.

• CH 2  ;-0.5MV/DIV. 10-15MV.

CH 3  :-5V/DIV. 0-50v.

I

• NOTE:

If sufficient resolution to Jetect a change of 0.1 MV cannot be obtained using a brush recorder, an alternative measurement device should be employed. If this is required, document additional connections on this figure, and list required equipment information in Step 2.9.

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