ML13204A256

Handout - LOOP Voltage Setpoint Change Presubmittal Conference Call - July 9, 2013

ML13204A256
Person / Time
Site:	Harris
Issue date:	07/09/2013
From:	Duke Energy Progress
To:	Billoch-Colon A Plant Licensing Branch II
Billoch-Colon, Araceli
Shared Package
ML13204A262	List: ML13204A256
References
TAC MF1498
Download: ML13204A256 (10)

Text

LOOP Voltage Setpoint Change Presubmittal Conference Call - July 9, 2013

Harris Loop Voltage Setpoint Change Participants John Caves, Licensing Engineer Brian Mayall, Design Supervisor Vinod Puri, Design Engineer Agenda

Background

Description of Change Change Basis 2

Harris Loop Voltage Setpoint Change

Background

CDBI Inspection Finding there was reasonable doubt as to whether the permanently connected safety-related loads would remain available to respond to a LOOP following a non-accident degraded voltage condition, for the duration of the time delay chosen for the degraded voltage relay.

Licensing and design bases were not up to current standards Analytical limits not fully established Bases for allowable values and trip setpoints over-used engineering judgment and industry-standard practices at the time Resolves non-conservative technical specification Independent of license amendment request currently under review by NRC staff for degraded voltage time delay setpoints 3

Harris Loop Voltage Setpoint Change Description of Change Table 3.3-4 Engineered Safety Features Actuation System (ESFAS) Instrumentation Trip Setpoints Revise Unit 9.a, Loss of Offsite Power 6.9 kV Emergency Bus Undervoltage - Primary Allowable value voltage change from >= 4692 volts to >= 5329 volts Allowable value time delay unchanged at <= 1.5 seconds Trip setpoint voltage change from >= 4830 volts to >= 5454 volts Trip setpoint time delay change from <= 1.0 seconds to <= 1.46 seconds 4

(

5454 1.46 5329 TABLE 3.3-4 (Continued)

ENGINEERED SAFETY FEATURES ACTUATION SYSTEM INSTRUMENTATION TRIP SETPOINTS SENSOR TOTAL ERROR FUNCT IONAL UN IT ALLOWANCE ~TA~ l ~S~ TRIP SETPOINT ALLOWABLE VALUE

9. Loss-of-Offsite Power

a. 6.9 kV Emergency Bus N.A. N.A. N.A. ~ 4830 volts ~ 4692 volts with Undervoltage--Primary with a ~ 1. 0 a time delay ~ 1.5 second time seconds delay.

b. 6.9 kV Emergency Bus N.A. N.A. N.A. ~ 6420 volts ~ 6392 volts with Undervoltage--Secondary with a ~ 16 a time delay ~ 18 second time seconds (with delay (with Safety Injection).

Safety Injection) .

~ 6420 volts ~ 6392 volts with with a ~ 54.0 a ~ 60 second time second time delay (without delay (with- Safety Injection).

out Safety Injection) .

10. Engineered Safety Features Actuation System Interlocks

a. Pressurizer Pressure.

P-ll N.A. N.A. N.A. ~ 2000 psig ~ 1988 psig Not P-ll N.A. N.A. N.A. ~ 2000 psig ~ 2012 psig

b. Low-Low Tavg. P-12 N.A. N.A. N.A. ~ 553°F ~ 549.3°F SHEARON HARRIS - UNIT 1 3/4 3-34 Amemendment No. 107

Harris Loop Voltage Setpoint Change Change Basis - Voltage Setpoints Lower analytical limit for voltage established based upon procurement specifications and voltage drop calculations Motors rated at 6.6 kV Nominal bus voltage is 6.9 kV Procurement spec required operation at 75% rated voltage for 1 minute at motor terminal Calculation basis for voltage drop from bus to motor terminals Minimum allowable value and trip setpoint calculated using standard setpoint methodology Maximum analytical limit, allowable values, and trip setpoints calculated and incorporated into design basis but not in technical specifications, not part of this LAR.

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CALCULATION 0054-JRG ATTACHMENT N PAGE N3, REV. 4 Decreasing Setpoints Form (LOOP Dropout)

PE +/-0.36V Bias1 N/A PME N/A Bias2 N/A TDUsensor N/A Bias3 N/A TDU1 +/-2.89V Total Bias N/A TDU2 N/A TDU3 N/A 2 2 1/2 TLU = (PE + TDU1 )

TLU +/-2.91V Margin Upper 225V Lower 72V 2 2 1/2 GAFT = (DR1 + MTE1 )

GAFT +/-2.09V 2 2 2 2 LAFT = (GAFT + ALTsensor + DRsensor + MTEsensor )1/2 LAFT N/A Upper Analytical Limit = 5926V, 98.8V TLU (175V, 2.91V) Upper Allowable Value (5876V, 98V)

GAFT (125V, 2.09V)

Max Allowable Setpoint (5751V, 95.9V)

Margin (225V, 3.8V)

Setpoint (5526V, 92.1V)

(MST Setpoint is 92.1V)

Margin (72V, 1.2V)

Min Allowable Setpoint (5454V, 90.9V)

(T/S Trip Setpoint is 5454V)

GAFT (125V, 2.09V)

TLU (175V, 2.91V)

Lower Allowable Value (5329V, 88.8V)

T/S Allowable Value > 5329V Lower Analytical Limit = 5279V, 88.0V

Harris Loop Voltage Setpoint Change Change Basis - Time Delay Setpoints Current time delay allowable value (1.5 seconds) originally established based upon standard TS during original licensing. An analytical limit was not used explicitly.

Time delay:

short enough to prevent damage or protective device trip due to exposure to voltage substantially below the rated value long enough to avoid spurious trips from faults or other very short term transients Current TS maximum allowable value meets criteria, therefore kept for consistency Analytical limit reverse engineered from current allowable value and verified to support criteria Trip setpoint calculated using standard setpoint methodology Minimum analytical limit, allowable values, and trip setpoints calculated and incorporated into design basis but not in Technical Specifications, not part of this LAR.

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CALCULATION 0054-JRG ATTACHMENT N PAGE N5, REV. 4 Increasing Setpoint Form (LOOP Time Delay Relay)

PE N/A Bias1 N/A PME N/A Bias2 N/A TDUsensor N/A Bias3 N/A TDU1 +/-0.0431 Total Bias N/A TDU2 N/A TDU3 N/A 2 2 1/2 TLU = (PE + TDU1 ) + Total Bias TLU +/-0.0431 Margin Upper 0.26 Lower 0.282 2 2 2 1/2 GAFT = (ALT1 + DR1 + MTE1 ) + Total Bias GAFT +/-0.0404 2 2 2 2 LAFT = (GAFT + ALTsensor + DRsensor + MTEsensor )1/2 LAFT N/A Upper Analytical Limit = 1.503s Upper Allowable Value (1.5s)

TLU (0.0431s) T/S Allowable Value 1.5s GAFT (0.0404s)

Max Allowable Setpoint (1.46s)

T/S Trip Setpoint 1.46s Margin (0.26s)

Setpoint 1.2s Margin (0.282s)

Min Allowable Setpoint (0.918s)

GAFT (0.0404s)

TLU (0.0431s) Lower Allowable Value (0.878s)

Lower Analytical Limit = 0.875s

Harris Loop Voltage Setpoint Change Additional Discussion No directly applicable precedent Used San Onofre concepts (significantly different TS structure)

Schedule Submit in August 1 year approval requested Open Discussion/Questions 10