ML20099L348

From kanterella
Jump to navigation Jump to search
Applicant Exhibit A-196,consisting of Paper Re Vogtle Experience W/Calcon Sensors in DG Trip Circuits
ML20099L348
Person / Time
Site: Vogtle  Southern Nuclear icon.png
Issue date: 09/19/1995
From:
GEORGIA POWER CO.
To:
References
OLA-3-A-196, NUDOCS 9512210214
Download: ML20099L348 (13)


Text

e y h j GPC Exhibit II- j[

Hill / Ward Exhibit B

3. VOGTLE EXPERIENCE WITH CALCON SENSdHS 1R 20 P 4 :45 DIESEL GENERATOR TRIP CIRCUITS OFFICF OF ?ERi f4 3Y 3.1 Vogtle 1 (8/14/85) 00COggBV1CE Appendix I states: "A lube oil pressure sensor (Model B4400) was discovered with a setpoint out of calibration low and was recalibrated. The cause of the setpoint drift was not determined."

Response: This date appears to be in error. Refer to Line 3.4 below.

3.2 Vogtle 1 (8/17/85)

Appendix I states: "A Calcon jacket water high temperature sensor (Model A-3500-W3) was discovered during constmetion acceptance testing with a setpoint out of calibration low and was recalibrated. The cause of the setpoint drift was not determined."

Response: This appears to be a duplicate of line 3.7 below.

3.3 Vogtle 1 (8/17/85)

Appendix I states: "A Calcon lube oil low pressure sensor (Model B4400) was discovered with a setpoint out of calibration high and was recalibrated. The cause of  ;

the setpoint drift was not determined."

Response: This date appears to be in error. RCer to line 3.4 below 3.4 Vogtle 1 (8/19/85) l Appendix I states: "A Calcon tube oil low pressure sensor (Model B4400) was discovered i with a setpoint out of calibration high and was recalibrated. The cause of 1 the setpoint drift was not determined."  ;

Response: All five of the lube oil pressure switches (1PS-4749 A, B, C, D, and E) for l DGIA received their initial calibration under Constmetion Acceptance Test procedure CAT 85-2204. This procedure established the correct VEGP l setpoints a these new switches; thus there was no setpoint drift since there l was no previous setpoint.

  • * ~

NUCLE /.R REGULATORY COMMISSION Docket No. 50-424/425-OLA.S EXHIBITNO. I- Ik b 9512210214 950919 in the rnatterp Georata Power Co. et al, Voatie Units t & 2

{DR ADOCK0500g4 O Staff EApplicant O lntwvenor D Other

. O identif;ed eived O Rejected Reporter 5~b Date 9 [li / 5' Witness M OL 4 f_ W A ,4 D __

e 4-1 l

3.5 Vogtle 1 (8/19/85)

Appendix I states: "A Calcon jacket water low pressure sensor (Model B4400) was discovered l with a setpoint out of calibration high and was recalibrated. The cause of  !

the setpoint drift was not determined." l l

Response: This was the initial calibration of IPSL-19114 for DGIA, under Procedum CAT 85-2204. No setpoint drift could have occurmd.

3.6' Vogtle 1 (8/20/85)

Appendix I states: "A Calcon jacket water high temperatum sensor (Model A-3500-W3) during constmetion acceptance test was discovemd with a setpoint out of calibration high and was recalibrated. The cause of the setpoint drift was not determined."

Response: This was the initial calibration of ITSH-19110 for DGI A, under Procedure CAT 85-2204. No setpoint drift could have occurred.

3.7 Vogtle 1 (8/20/85)

Appendix I states: "A Calcon jacket water high temperature sensor (Model A-3500-W3) during constmetion acceptance testing was discovered with a setpoint out of calibration high and was recalibrated. The cause of the setpoint drift was t not determined."

Response: This was the initial cr.libration of ITSH-19111 for DGI A, under Procedure

! CAT 85-2204. No setpoint drift could have occurred.

3.8 Vogtle 1 (8/24/85) -

l Appendix I states: "A Calcon low turbo oil pressum sensor (Model B4400) during construction acceptance testing was discovered with a setpoint out of calibration low and was mcalibrated. The cause of the setpoint drift was i not determined."

Response: This date appears to be in error. Refer to Line 3.4 above for IPSL-4749C. ,

i l.

, 2 4

L____'_._._____-.

, -. . _ . - . - - . .~

4 3.9 Vogtle 1 (10/28/85)

Appendix I states: "Three Calcon jacket water high temperatum sensors (Model A-3500-W3) were discovered with a setpoint out of calibration low and were i recalibrated. The cause of the setpoint drift was not determined."  !

Response: During constmetion testing of the DG, the System Engineer wrote MWO 18511662 to perform an in-place calibration of DGlB switches ITSH- ,

19117, ITSH-19118, and ITSH-19119, using the permanently installed 7, air tubing instead of a bench test rig in the shop. They wem found out-of-specification low (180,185, and 176 F), when compared to the previous bench calibration setpoints. This change could have been due to the diffemnce in calibration techniques, drift, or a combination of these factors.

3.10 Vogtle 1 (11/14/85)

Appendix I states: "A Calcon jacket water high temperature senser (Model A-3500-W3) failed and was replaced. The cause of the failure was not determined."

Response: MWO 18512461 was written on this date, during constmetion testing, and -

. states to replace switch ITSH-19119 on DG1B with an acceptable switch.

MWO 18512094 was written on 11/5/85 and states that the switch is ,

venting continually; a new switch was calibrated and installed on 12/12/85 to resolve both MWOs. Since the switch had been readjusted upward a few days earlier (see 3.9) but was still venting, a plausible cause was leakage due to debris in the valve, which was later determined to be a problem.

i.

l l 3.11 Vogtle 1 (12/10/85) i l Appendix I states: "A Calcon jacket water high temperature sensor (Model A-3500-W3) was discovered with a setpoint out of calibmtion low and was recalibrated. The i cause of the setpoint drift was not determined."

! Response: The System Engineer wrote MWO 18513689 to perform an in-place i calibration of DGIA switch ITSH-19111 during constmetion testing of the l DG. It was found out-of specification low (185F) when compared to the

. previous satisfactory bench test. That change could have been due to a difference in calibration techniques, drift, or a combination of these factors.

j 1

1 3

l l _

e 3.12 Vogtle 1 (12/11/85)

Appendix I states: "A Calcon jacket water high temperature sensor (Model A-3500-W3) was discovered with a setpoint out of calibration low and was recalibrated. The cause of the setpoint drift was not determined."

Response: This was the initial calibration of ITSH-19112 for DG1A, under Procedure CAT 85-2204. No setpoint drift could have occurred.

3.13 Vogtle 1 (2/11/86)

Appendix I states: "A Calcon lube oil low pressure sensor (Model A-3500-W3) was found with a setpoint out of calibration low and was recalibrated. The cause of the setpoint drift was not determined."

Response: This was the initial calibration of ITSH-19146 for DGI A under Procedure CAT 85-2204. No setpoint drift could have occurred. This switch is a temperature sensor and not a pressure sensor, as stated in the NUREG, and the calibration was actually performed on 1/3/86.

3.14 Vogtle 1 (12/22/86)

Appendix I states: "A Calcon lube oil low pressure sensor (Model B4400) would not calibrate I in specification and was replaced. The cause of the malfunction was not i

determined."

l Response: MWO 18624684 states to obtain a new turbocharger low pressure turbo oil l trip sensor and to replace IPS-4749D on DG1A. The MWO does not state l that the sensor "would not calibrate in specification." The source of this statement in the NUREG could not be determined.

4

3.15 Vogtle 2 (1/24/88)

Appendix I states: "A Calcon vibration switch sensor (Model E4600) was found defective and replaced with new vibration switch. The cause of the malfunction was not detennined."

Response: This occurred during the construction testing period. This switch is different than Calcon temperature sensors and was not involved in the Site Area Emergency in 1990.

3.16 Vogtle 2 (2/5/88)

Appendix I states: "A Calcon low turbo oil psessure sensor (Model B4400) was discovered with a setpoint out of calibation high and was recalibrated. The cause of the setpoint drift was not determined."

Response: This occurred early during the construction testing period. No further information was found.

3.17 Vogtle 2 (2/26/88)

Appendix I states: "A Calcon lube oil high temperature sensor (Model A-3500-W3) was discovered with a setpoint out of calibration low and was recalibrated.

The cause of the setpoint drift was not determined."

Response: The System Engineer wrote MWO 28801450 to perform an in-place calibration check of 2TSH-19153 on DG2B during construction testing.

l 'Ihe as-found setpoint for this switch was out-of-specification low (190F).

This occurred about one month after the initial calibration of the switch and, most likely, occurred due to differences in calibration techniques.

4 3.18 Vogtle 2 (4/13/88) i Appendix I states: "A Calcon vibration detector sensor (Model E4600) was replaced due to a

defective switch. The cause of the defective switch was not determined."

Response: This occurred during construction testing period. This switch is different than l

j Calcon temperature sensors, and was not involved in the Site Area Emergency in 1990.

I f

5 l

'4 3.19 Vogtle 2 (4/21/88)

Appendix I states: "A Calcon jacket water high temperature sensor (Model A-3500-W3) was discovered with a setpoint out of calibration low and was recalibrated. The -

cause of the setpoint drift was not determined."

Response: The System Engineer wrote MWO 28803452 to recalibate switch 2TSH-19119 on DG2B, because it was observed to be continuously venting. This occurred about one month after initial installation of the switch. The switch had an as-found setpoint of 158.6F,which was approximately 40F lower than the initial setpoint one month earlier. This difference could have been due to drift, as assumed in the NUREG, but was more likely a result of differences in calibration techniques.

3.20 Vogtle 2 (4/24/88)

Appendix I states: "Three Calcon high jacket water temperature sensors (Model A-3500-W3) were discovered with setpoint out of specification low and were recalibrated.

The cause of the setpoint drift was not determined." i i

Response: MWO 28803648 reported that three JW temperature switches (2TSH-19110, j 2TSH-19111, and 2TSH-19112) on DG2A were venting. As-found setpoints were 180.0F,185.1F and 181.5F, respectively. This difference could have i been due to drift, as assumed in the NUREG, but was more likely a result of

! difference in calibration techniques. This problem occurred during l construction testmg. l 3.21 Vogtle 2 (7/22/88)

. Appendix I states: "Three Calcon jacket water high temperature sensors (Model A-3500-W3) 2 were discovered with a setpoint out of calibration low and were recalibrated. l The cause of the setpoint drift was not determined."

Response: MWO 28807390 reported that two JW temperature sensors tripped while running a startup test of DG2B involving the JW temperature control valve, and stated that one switch tripped at a process temperature of about 172 F; i the second switch tripped at a process temperature of about 179 F. The as-

found setpoints were 181.5F (2TSH-19117),173.4F (2TSH-19118), and i 189.1F(2TSH-19119). The change from previous setpoints could have been due to drift, but was more likely a result of differences in calibration
techniques. This problem occurred during construction testing.

l I

L 6 l

3.22: Vogtle 1 (9/30/88)

Appendix I states: "Three Calconjacket water header outlet temperature sensors (Model A-3500-W3) were discovered with a setpoint out of calibration (2 high,1 low) and were recalibrated. The cause of the setpoint drifts was not detennined."

Response: MWO 18806910 performed routine calibmtion on several instmments on DG1B during the first refueling outage. ITSH-19117,1TSH-19118, and ITSH-19119 were all found out of calibration high at 220.1F,213F, and 221.3F, respectively, on 10/20/88. These readings were obviously obtained using a different calibration technique than normal, since a water calibration bath cannot achieve the above temperatures at atmospheric pressure. Thus, using this inappropriate technique not only yielded suspicious test results, but was used to improperly reset the switches downward.

3.23 Vogtle 1 (10/10/88) i Appendix I states: " Ten Calcon bearing high temperature sensors were found to be defective and were replaced. The cause of the malfunction was not documented."

Response: This problem was caused by destructively testing the sensors during routine calibration during the first refueling outage. No defective sensors nor

! malfunctions were observed. l 1

3.24 Vogtle 1 (10/13/88)

. i Appendix I states: "A Calcon jacket water high temperature sensor was discovered out of l' calibration high and was recalibrated. The cause of the calibration drift was i not determined."

Response: MWO 18806902 performed routine calibration on several instruments on DGI A during the first refueling outage. ITSH-19110 and ITSH-19111 had as-found setpoints of 226.5F and 229.5F, respectively. The high out-of

specification readings were obviously obtained using a different calibration

, technique than normal, since a water calibration bath cannot achieve the above temperatures at atmospheric pressure. Thus, using this inappropriate technique

, not only yielded suspicious test results, but was used to improperly reset the switches downward.

i l

l i

7

l 1

3.25 Vogtle 1 (10/19/88)

Appendix I states: "A Calconjacket water high temperature sensor (Model A-3500-W3) was not l working properly and was replaced. The reason for the switch malfunctiomng was not documented."

Response: MWO 188M902 (reference 3.24 above) determined that ITSH-19112 on DGI A was defective during the first refueling outage mutine calibration.

On 10/18/88, the switch was replaced using MWO 18805581. The documentation does not explain what was wrong with the old 2 witch.

3.26 Vogtle 1 (10/20/88)

Appendix I states: "A Calcon low lobe oil pressum sensor (Model B4400) was discovered with a setpoint out of calibration high and was recalibrated. The cause of the setpoint drift was not determined."

Response: MWO 18806914 was written to perform routine calibration of several instruments on DGI A during the first refueling outage. All five of the lube oil pressure sensors (IPS-4749 A, B, C, D, and E) were found in-specification on 10/10/88 and 10/11/88.

3.27 Vogtle 1 (10/20/88)

Appendix I states: " A Calconjacket water header pressure sensor (Model B4400) was discovered i with a setpoint out of calibration high and was recalibrated. The cause of the setpoint drift was not determined."

Response: MWO 18806831 was written to perform routine calibration of several instniments on DGI A during the first refueling outage. Jacket water header pressure switch 1 PSL-19114 was found in-specification, but was readjusted to the nominal setpoint on 10/18/88.

3.28 Vogtle 1 (10/21/88)

Appendix I states: "A Calcon low lube oil pressure sensor (Model B4400) was discovered with

setpoint out of calibration high and was recalibrated. The cause of the setpoint drift was not determined."

Response: This appears to be a duplicate of 3.26 above. No lube oil pressure switches were out of calibration.

8

3.29 Vogtle 1 (10/23/88)

Appendix I states: "Two Calcon normal trip pressure sensors (Model B4400) failed. One sensor .

i would not respond and the other failed to reset within tolerance. The cause i of the failures were not documented."

Response: MWO 18807465 was written to verify the correct setpoint for logic switch

1PSL-4903 on DG1B. The switch would not trip within tolerance and was
replaced on 10/25/88. MWO 18807466 was written to verify the cornet setpoint for logic switch IPSL-4902 on DGI A. The switch would not reset i within tolerance and was replaced on 11/3/88. Both of these problems ,

occurred during the first refueling outage.

3.30 Vogtle 1 (10/26/88)

Appendix I states: "A Calcon jacket water header outlet temperature sensor (Model A-3500-W3) switch would not calibrate. The cause of the failure was not determined."

Response: MWO 18807637 stated that ITSH-19119 on DG1B was leaking and should be replaced. A new switch was obtained but would not calibrate satisfactorily.

Another new switch was calibrated and installed. 'Ihis work was performed on 10/27/88,which was only a few weeks after the installed switch had been reset downwarti about 20F (see Item 3.22 above). No explanation is provided for failure of the first replacement switch to be calibrated, but in subsequent years some new switches were determined to have foreign material in the valve poppet area which prevented the switch from being ret correctly. The original switch setpoint discrepancy appears to be very similar to later observations that note the importance of using consistent calibration techniques.

3.31 Vogtle 1 (10/30/88)

Appendix I states: "Two Calcon jacket water temperature sensors (Model A-3500-W3) were found to be defective tud were replaced. The cause of the failures was not documented."

Response: MWO 18807746 stated that, during a nm of DGIA on 10/30/88, an annunciator indicated a malfunction of jacket water temperature switches.

Switches ITSH-19110,-19111, and -19112 were checked with air and found not to be leaking. Switches ITSH-19110 and ITSH-19111 were removed and calibration checked in the shop with as-found setpoints of 193.7Fand 193.4F, respectively, on 11/3/88,which was only slightly out of specification. They 9

were then reinstalled to support DG operability. On 11/19/89, three new switches were obtained, and all three JW high temperature switches were replaced. No explanation was provided for the initial DG annunciator problem in the documentation, but foreign material in one of the switches is one potential explanation, based on subsequent observations with those components. However, the NUREG statement does not appear to be an accurate representation of the actual problem.

3.32 Vogtle 1 (10/31/88)

Appendix I states: "Two Calcon jacket water header outlet temperature sensors (Model A-3500-W3) were replaced. The reason was not documented."

Response: For no documented reason, MWO 18807793 was written on 10/31/88 to replace DGlB switches ITSH-19117 and -19118. New switches were calibrated and installed on 11/1/88. This problem occurred only a few weeks

, after the installed switches had been reset downward by 12-20F (see Item 3.22 above), and only a few days after the third switch was replaced on the same DG (see Item 3.30 above). The setpoint problems appear to be very similar to later observatior.s that note the importance of using consistent calibration techniques.

3.33 Vogtle 2 (12/9/88)

Appendix I states: "A Calcon vibration sensor (Model E4600A) was malfunctioning causing the

{ emergency diesel generator to trip. The sensor was replaced. The cause of the malfunction was not documented."

3.33 (continued)

Response: This ocorred during startup testing of Unit 2. This switch is different than Calcon temperature sensors, and was not involved in the Site Area Emergency in 1990.

3.34 Vogtle 1 (11/19/89)

Appendix I states: "A Calcon high jacket water temperature sensor (Model A-3500-W3) was discovered with a setpoint out of calibration low and was recalibrated. The  !

cause of the setpoint drift was not determined." j l

Response: This appears to be a duplicate of the problem discussed in Item 3.31 above l

(final switch replacement date).

I 10 l I

9 3.35 Vogtle 1 (12/5/89)

Appendix I states: " A Calcon lube oil pressure sensor (Model B4400) was found defective during a calibration check and was replaced with a new switch. The cause of failure was not documented."

Response: No record of the above problem was found on this date.

3.36 Vogtle 1 (1/3/90)

' Appendix I states: "A Calcon turbo oil pressure sensor (Model B4400B) was venting and was replaced. Cause of the failure was not determined."

. Response: No record of the above problem was found on this date. Also, the switch

. model number is not correct for VEGP switches.

J i

[

i 3.37 Vogtle 1 (1/25/90)

! Appendix I states: "A Calcon lube oil temperature sensor (Model A-3500-W3) was discovered with a setpoint out of calibration high and was recalibrated. The cause of the

, setpoint drift was not determined."

Response: MWO 19000439 was written on 1/25/90to perform routine outage calibration of many instruments on DGI A. On 3/3/90,during the outage, ITSH-19146 was found to be set at 211F and was reset to approximately 200F. Since the switch was calibrated at 200F in January,1986, and checked at 202F in October,1988, but three weeks later was found to be set 10F low, it appears

that a different calibration technique was used on 3/3/90.

l 3.38 Vogtle 1 (1/25/90)

Appendix I states: "Three Calcon jacket water header outlet temperature sensors (Model A-3500-W3) were discovered with set points out of calibration high and were recalibrated. The cause of the setpoint drifts was not determined."

i Response: MWO 19000439 was written on 1/25/90to perform routine outage calibration

of many instruments on DGIA. On 3/1/90 and 3/2/90, during the outage, jacket water temperature switches ITSH-19110, -19111, and -19112 were found to be set at 210F,206.2F,and 210.4F,respectively. They were reset to the correct setpoints and were reinstalled on the engine. Each of the calibration data sheets contains a note by the technician that states, "...the values indicated above are an average taken of three cycles." These switches 11

9 wert, in place on DGI A and tripped the engine apptuximately three weeks later during the Site Area Emergency on 3/20/90. The calibration method used during this procedure would have maintained the switch at an elevated temperature while the setpoint was adjusted downward and while the new setpoint was verified three times. Subsequent evaluation has shown that thermal growth of the switch at elevated temperatures will result in an improperly suppressed final setpoint.

3.39 Vogtle 1 (3/3/90)

Appendix I states: "A Calcon jacket water low pressure trip sensor (Model B4400) was discovered with a setpoint out of calibration high and was recalibrated. The cause of the setpoint drift was not determined."

Response: MWO 19000439 performed routine outage calibration on DGI A switch 1PSL-19114. The switch was found to be about 2 psig out of specification and was reset.

3.40 Vogtle 1 (3/4/90)

Appendix I states: "A new Calcon high temperature main bearing sensor (Model 3434) switch was installed. The reason the new switch was needed was not documented."

Response: This sensor was destructively tested during the IR2 outage on DGI A and was replaced with a new switch.

f 3.41 Vogtle 1 (3/23/90)

Appendix I states: "Three Calcon jacket water header outlet temperature sensors (Model A-3500-W3) were checked for calibration. Two switches were found out of calibration. One switch did not pass the bubble test and was replaced. The  ;

l other two were recalibrated."

l i

Response: MWO 19001511 documents work that was performed on DG1B during its IR2 overhaul immediately following the Site Area Emergency. All three jacket water temperature switches (ITSH-19117, -19118, and -19119) were

! found set about 10F low, and two of them exhibited some leakage and were replaced. Subsequent examination showed that leakage was caused by foreign material in the switch poppet valve.

4

! 12

{

3.42 Vogtle 1 (3/25/90)

Appendix I states: "A Calcon lube oil high temperature sensor (Model A-3500-W3) was discovered with a setpoint out of calibration high and was recalibrated. The cause of the setpoint drift was not determined."

Response: MWO 19001511 states that switch ITSH-19153 on DG1B was venting continuously and was defective. This work occurred as pan of the restoration of DG1B following the Site Area Emergency on 3/20/90.

3.43 Vogtle 1 (3/25/90)

Appendix I states: "A Calcon stan logic air pressure sensor (Model B4400) was found malfunctioning during a surveillance procedure. The defective sensor was replaced. The defective switch was subsequently tested satisfactorily. The cause of the malfunction was not determined."

Response: MWO 19001542 replaced defective P3 switch IPS-4903 on DG1B as pan of restoration from the routine overhaul following the Site Area Emergency.

This switch was subsequently tested and tripped within specification at the same setpoint three consecutive times; therefore, the sensor was determined to not be defective.

SUMMARY

l The above data review reinforces that different calibration techniques used on the temperature switches had a major impact on the switch settings. Several instances are seen where a switch would be found set too high and would be adjusted downward, then a few days later would be reponed leaking and would be found set too low. This is the same exact sequence that occurred on DGI A on 3/3/90 and 3/20/90,resulting in the Site Area Emergency (see 3.38 and 3.41 above).

l 4

L 13 L