7505_H.M. Hashemian_PM

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Advanced I&C

On-line Monitoring and Calibration

Techniques in Nuclear Power Plants

Prepared by:

H.M. Hashemian, PresidentAnalysis and Measurement Services Corporation

AMS Technology Center

9119 Cross Park Drive

Knoxville, Tennessee 37923

USA

Presented at:

International Conference onOpportunities and Challenges

for Water Cooled Reactors in 21st Century

Vienna International Centre

International Atomic Energy Agency

Vienna, Austria

27-30 October 2009



Do Not Forget Sensors and Cables

2H.M. Hashemian

Process

TemperatureSensor

PressureTransmitter

Cables

Cables

Penetration

I&C Cabinets(Analog or Digital)

Control Room Area(Mild Environment)

Containment(Harsh Environment)

~150 meters



Proper Installation is Critical toTemperature Sensor Performance

3H.M. Hashemian

0

4

8

12

R e s p o n s e T i m e ( s e c )

Thermocouple Tag Number

DWM139B-01A

0

1

0 10 20 30 40 50 60

Time (Sec)

S t e p R e s p o n s e

Fast - Good

Slow - Bad

RTD

Thermocouple



Nuclear Power Plant Pressure TransmitterFailure Mode Detected by Pure Luck

4H.M. Hashemian

80

90

100

110

120

9:30 AM 10:00 AM 10:30 AM 11:00 AM 11:30 AM 12:00 PM 12:30 PM

R C S F l o w ( % )

Time

JPF025B-04

FT-445

FT-444



Sensing Lines are Critical to thePerformance of Pressure Transmitters

5H.M. Hashemian

Process Pipe orVessel

CondensatePot

Vent

ThermalInsulation

Rootvalve

Shield Wall

Penetration

AccessibleIsolation Valve

Transmitter

PrimaryContainment

Wall

RestrictionDevice

Check Valve

~ 50 meters



Cable Diagnostics

1 2 3 4

RTD

-0.5

0

0.5

-200 0 200 400 600 800 1000

1,2

2,3

3,4

Distance (Feet)

6H.M. Hashemian



Signal Problems are Not Always inCables

CurrentMeter

N e u t r o n s

CurrentVoltageSource

+

NeutronDetector

7H.M. Hashemian

-

I – V Test


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MaintenanceClasses

PredictiveMaintenance

Methods that useData from TestSensors


Methods that useData from ExistingProcess Sensors


Methods Based onActive MeasurementSignals

Detection ofFouling of

Venturi FlowElements

Detection ofSensing Line

Blockages

InstrumentCalibrationVerification

Loose PartsMonitoring

LeakageMonitoring

VibrationMeasurement

SensorInstallationVerification

SensorResponse Time

Testing

Cable ConditionMonitoring

Conventional and Advanced PredictiveMaintenance Technologies



Plant Implementation of On-LineCalibration Monitoring

H.M. Hashemian 9

PlantComputer

Data

Status of Plant Instrumentation



Plant Startup and Shutdown Data

10H.M. Hashemian

0

10

20

30

40

50

60

70

80

90

0 500 1000 1500 2000 2500

P r e s s u r e

Time (Minutes)

Startup Data KDL204A-01

0

10

20

30

40

50

60

70

80

90

0 300 600 900

P r e s s u r e

Time (Minutes)

Shutdown Data KDL204A-02



On-Line Calibration Monitoring Results Coveringthe Full Operating Range of a Transmitter

11H.M. Hashemian

-1.0

-0.5

0.0

0.5

1.0

7.5 20 30 40 50 60 70

Operating Point (%)

+ (ALLOWABLE CALIBRATION LIMIT)

- (ALLOWABLE CALIBRATION LIMIT)

CRS038B-01

D e v i a t i o n

( % )



Conclusions and Recommendations

• Do not forget the sensors, process-to-sensors interfaces, cables,connectors, and penetration

• The validity, accuracy, and fidelity of process signals depends onproper installation of sensors and flawless cables and connectors

• On-line monitoring techniques and in-situ test methods are now

mature enough for ready use in nuclear power plants

• Regulators have approved the OLM concept to verify the calibrationof nuclear plant pressure, level, and flow transmitters

• U.S. plants are applying for generic NRC licensing to implement

OLM for online calibration monitoring of pressure, level, and fortransmitters

• Research is needed to establish the uncertainty of modelingtechniques for on-line calibration monitoring applications

H.M. Hashemian 12



Thank You

13H.M. Hashemian

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