Flow Meter Technology

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Flow meter Technology

Selection

Your Flow MeasurementExperts



Emerson Confidential

Slide 2

Flow Techno logy Select ion Flow Technology Selection Process

Application/Purpose of Measurement

Performance

Cost/Economics

Select Flow meter

Purpose of MeasurementControl – to maintain proper flow

Monitoring – track usage or discharge

Custody Transfer – billing purposes

Quality – achieve proper recipe

Batch Chemical Feed systems

Installed vs. Reference Performance

****System Accuracy *****

RepeatabilityResponse Time

Upstream & Downstream Piping Permanent

Pressure Loss

Price/Installed Cost/Life-Cycle CostMaterial Cost

Installation ( Existing or new pipe )

ReliabilityMaintenance

Power / no power

Actions: Review purpose of measurement, keyperformance criteria, environmental

considerations, approvals

Actions: Complete Spec Sheet, Size Flow

meters for application, complete InstalledPerformance analysis. Min Max and averageflows. Is the pipe always full ?

Actions: Consider schedule, price, cost to Install,

operating costs (Reliability, Maintenance, Energy, etc.)




Slide 3

Invert to keep primary full

Flow Techno logy Select ion Any Flow meters – Piping Requirements




Slide 4

Flow Techno logy Select ion Types of Flowmeters

Ultrasonic7%

Anemometer

5%

Differential

Pressure29%

Vortex

4%

Mag

20%

Direct Mass

Measurement

18%

Turbine

8%

Positive

Displacement

9%




Slide 5

Flow Techno logy Select ion Differential Pressure No Power required

ADVANTAGES

Use on liquid, gas, and steam

Good application flexibility

Suitable for extreme temperaturesand pressures

Moderate accuracy – 2 to 5%

Moderate pressure loss

No moving parts

DISADVANTAGES

Expensive to install

Limited range ability 4:1

Affected by changes in density,pressure, and viscosity

Maintenance intensive ( Bleed )




Slide 6

Static

Pressure

Differential

Pressure

Stagnation

Pressure

Permanent

Pressure Loss

Pressure

Flow Techno logy Select ion Differential Pressure – Theory of Operation

DP K Flow

DP Ed Y NC Q Dm

2

1






Slide 8

Flow Techno logy Select ion Differential Pressure – Venturi and Nozzle

ADVANTAGES

Use on liquid, gas, and steam

Venturi principally used in Water & Wastewater applications

Nozzle used in Steamapplications

Low system pressure loss

Do not require upstream flowprofiling

DISADVANTAGES

Limited rangeability 6:1 &accuracy ±2%

Expensive to install Requires high Reynolds numbers

(>10,000)

Large acceptance

Venturi

Nozzle






Slide 10

Flow Measu rement Princ iples Percent of Error versus Flow




Slide 11

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85

Flow Rate (%)

90 100

1000:1 Turndown

Flow Techno logy Select ion “Flow Turndown” can be Misleading

20:1 Turndown 10:1 Turndown 10

%

8:1 Turndown 12.5%

4:1 Turndown 25%




Slide 12

Flow Coefficients not constant Solution: Embedded Flow Software

re-calculates ALL flow coefficients real-

time

Installed performance of transmitter over flow range

Solution: DP technology designed

to maximize performance in real-world conditions

Flow Techno logy Select ion 2 Sources of Flow Error

Source #2: Primary Element

Source #1: Transmitter




Slide 13

Minimize pressure loss

Best Practices Improve Flow Measurement

12.0%0.0% 4.0% 8.0%

Quantify and

optimize installed

performance

Eliminate

impulse lines

Select in-line flowmeter

for smaller line sizes &

insertion flowmeters for

larger line sizes

Expand

flow insight

with wireless

Utilize diagnostics to

enable predictive

maintenance

Simplify and

improve with

multivariableflowmetering

Reduce

piping

requirements

Measuremass

flow

http://clickthumbnail%2815%29/




Slide 14

Use Flow Technologies

with Minimum Straight-

Run Requirements

Optimize Performance in

Short-Straight Run

Applications

Put flowmeter where youwant it

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Lower Installed Cost and Improve Performance

Minimize Piping Requirements




Slide 15

Optimize Performance in StraightRun Applications

Coriolis

Orifice/

Nozzle

Vortex

Averaging

Pitot Tube

Magmeter

■ ■

■ ■

■ ■ 2221201918171615144 5 6 7 8 9 10 11 12 131 2 3

Conditioning

Orifice

Vortex

w/ K-FactorCorrection

4035302510 155 20

In-Plane

Out-of-Plane

0

-0.5

-1.0

-1.5

0.5

1.0

1.5

K-Factor Compensation

K - F a c t o r S h i f t




Slide 16

DP FLOW – Straight Run Requirements

Typical Straight Run Requi rements are

10 D’s Up stream and 5 D’s Downstream………

10 D’s ? 5 D’s ?

FLOW




Slide 17

Conditioning Orifice Plate

Each orifice hole is

positioned to help condition

flow profile irregularities

Geometry reshapes the

flow profile across the

entire pipe




Slide 18

Cond i t ion ing Plate for Sho rt Run Appl icat ions

Concept: Measurement of DP across a

“Flow Straightener”

Requires only 2D Upstream piping to meetaccuracy specification

– Independent of disturbance

405 Version

– Line Sizes: 2” to 12” (50 to 200 mm)

1495 Version

– Line Sizes: 6” to 72” (160 to 600mm)




Slide 19

Minimize pressure loss

Best Practices Improve Flow Measurement

12.0%0.0% 4.0% 8.0%

Quantify and

optimize installed

performance

Eliminate

impulse lines

Select in-line flowmeter

for smaller line sizes &

insertion flowmeters for

larger line sizes

Expand

flow insight

with wireless

Utilize diagnostics to

enable predictive

maintenance

Simplify and

improve with

multivariableflowmetering

Reduce

piping

requirements

Measuremass

flow

http://clickthumbnail%2815%29/




Slide 20

$184/year per leak PLUS additional costs:• Value of lost process fluid

• Value of lost energy

• Personnel safety and risk

• Environmental cost, impact

• Cost of inaccurate measurement

•

Maintenance cost of repairing leaks

*U.S. Dept. of Energy

Office of Industrial Technologies

www.oit.doe.gov/bestpractices

All but 2 potential leak

points factory leak-checked.

Removing Leak Points Saves Time & Money Direct Mounting Reduces Leak Points




Slide 21

Pot. Leak Points = 8

Leak Points

Tendency to Plug/Freeze

Inconsistent Measurement


Traditional Installation Best Practice Installation



Best Practice: Eliminate Impulse L ines to Improve Reliability

Single Casting No Internal

Tubing

Potential Leak Points = 36

Corner Tap

Design

Obstructionless

Consistency

Lower Cost




Slide 22

New DP transm it ters / More Reliab le & Cos t Effect ive Measu rement Pract ices

Traditional Installation

Direct Mount Installation

Remote

Operator

Interface

Multi-Bus Output

2X Performance

& Reliability

Integrated

Solutions




Slide 23

A 3-Year User-study* implementing Direct Mount technology

to replace Impulse Lines has been published. The results:

• 90% reduction in work orders

• 3000 applications over 3 years resultedin

only 6 work orders

•

46% reduction in total maintenancecost

* Copy of study avail able fr om Rosemount. Document 00802-0100-2071

Direct Mounting is More Reliable




Slide 24

How Do Our Customers Measu re Success? 18% Savings in Design & Procu rement

Traditional Practice

Specify & procure30 different parts

+

+

Design / Specify / Procure

Integrated DP Flowmeter

Single integratedassembly

Design / Specify / Procure




Slide 25

Propeller Meter Featu res

Designed for clean flows

Easy to install and operate

Easy to service in the field

Accuracy of +/- 2% of

reading Repeatability of +/- 0.25%

Self-clearing design

Instantaneous flow rate

Indicator & totalizer on everymodel

Flow range of up to 10:1

No Power Needed

Best sell ing ir r igation

meter in the Uni ted

States for agriculture

and turf ir r igation applications




Slide 26

How It Works

The Propeller Meter consists of a rotatingdevice, a helical-shaped impeller, positionedin the flow stream.

When fluid passes through the meter, itcontacts the impeller causing it to spin.

The impeller’s rotational velocity is directlyproportional to the velocity of the flow.

The rotation is translated through a magnetic

coupling and flexible drive system to theregister, which calculates the flow rate bymultiplying the flow velocity with the cross –sectional area of the meter tube.




Slide 27

Speci f icat ions No Power requ ired

Accuracy: +/-2%

Repeatability: +/-0.25%

Turndown: up to 10:1

Register options: optional FlowCom electronic digitalregister available; forward/reverse flow; test hand/indexwheel; anti-reverse totalizer; custom scale; extended digittotalizer

Impeller options: high temperature resistant; acid andcaustic resistant

Line sizes: from 2" to 96"

Flow Techno logy Select ion




Slide 28

Flow Techno logy Select ion Turbine Meters No Power

DISADVANTAGES

Only for low viscosities

Require upstream and down-stream flow conditioning

Require frequent calibrationMoving parts

Sensitive to flow profile

Vibration sensitive

Straightening vanes required

Needs 20 to 30 diameters of straight run




Slide 29

Accuracy about a 10:1 turndown

Higher accuracy at all operating ranges

r’s “Percent of Full Scale Accuracy”






Slide 31



THEORY OF OPERATION




Slide 33

• Understand how magmeters use Faraday’s Law

• Pulsed DC Vs. AC Magnetic Flow Meters

• Understand the advantages and limitations of magnetic flowmeters

Objectives

F d ’ L f El t ti




Slide 34

Faraday’s Law of Electromagnetic Induct ion

A voltage will be induced in a conductor

moving in a magnetic field (E) The magnitude of that induced voltage is

proportional

– to the velocity of the conductor (V)

– to the length of the conductor (D)

– to the strength of the magnetic field (B)

Michael Faraday (1791 - 1867)

E = k × B × D × VV

B

E

Fl T h l S l ti




Slide 35

V

B

DEs

Es

Magnet

coil

Electrode

Faraday’s Law of

Electromagnetic Induction

ES= the induced electrode voltage

B = the magnetic field density

V = liquid velocity

D = magmeter pipe diameter

C = non-dimensional constant

Flow Technology SelectionMagnetic Flow meters – Theory of Operation

BVD

C

E s

1




Slide 36

Magmeter Senso r Components

SensingElectrodes

Coils

LiningSST PipeFlange

E

VBD

SensingElectrodes

Coils

LiningSST PipeFlange

E

VBD

ProcessConnection

Coil Housing

M t Th




Slide 37

Magmeter TheoryFaraday’s Law and the Flow Rate

• All of the constants (k,B,D) areconverted into a CalibrationNumber during a flow labcalibration

– V = E / Calibration Number

• Q = V × A

– Volumetric flow rate (Q) is velocity(V) times cross-sectional area (A)

A

V

T

E = k × B × D × V

CalibrationNumber




Slide 38

Coil Exc itat ion Character ist ics

DC (0.5% of rate accuracy)

– More accurate

– Continuous automaticzeroing

– Magnetic field immune topower line disruptions

AC (1% of rate accuracy)

– Poor zero stability

– AC power required atflowtube

– High maintenance

– High power consumption – Good process noise

rejection




Slide 39

AC Flow Signal Diagram

Positive (A1)quadrature

voltage signal

Negative (A2)quadrature

voltage signal

Positiveflow signal

Time

Negativeflow signal

90 degreesphase

differential

Transmitter sensing positive

Transmitter sensing negative

+

0

-

When A1 = A2, quadrature voltage cancels

In phasenoise signal

AC C il E i t t i M th d R lt i Mi




Slide 40

AC Coi l Exc i tat ion Method Resu l ts in Mis- Measurement

Measurement Signal

Inductively coupled

interference voltages

High Excitation Currents and frequency results in fast

response time for a safe and stable measurement

Disadvantage: phase shift between signal and noisevaries over time

Result: Zero point drift



Emerson ConfidentialSlide 41

0

+

-

A

M

PL

I

T

U

D

E

One Measurement Cycle =

1/10 Line Frequency (6 Hz)

V Noise

E

E

1 2 3 4 5 6 7

Flow

Signal

(E + VNoise) - (-E + VNoise) = 2E

Magnetic field transition begins

Transients present due to transitionof magnetic field

Magnetic field and flow signal stabilize

Flow signal sampled

Magnetic field transition begins

Transients present due to transitionof magnetic field

Magnetic field and flow signal stabilize

Flow signal sampled; difference takenfrom previous sample. Flow rate

calculated.

1

1-2

2-3

3-4

4

4-5

5-6

6-7

EVENT SEQUENCE

Output Stage of transmitter is updated 12 timesper second regardless of coil drive frequency

Normal meter coil current 0.5 A

Pulsed DC Flow Elim inates Zero Drif t





Flow Techno logy Select ion Magnetic Flow meters – High-Powered Pulsed DC Coil Excitation

ADVANTAGES

Higher Coil Current Than ConventionalPulsed DC -0.7 to 5 A

Higher Exciter Frequency

– up to 33 Hz

Improved Signal-to-Noise Ratio compared toConventional Pulsed DC

Reads Lower Flow rates below 2 feet /second

DISADVANTAGES Only applies to sensors <20 in.

Exciter Frequency >15 Hz create zero drifterror

Higher Power Consumption than Conventional

Pulsed DC Higher Sensor Cost

C il E it t i




Coil Excitat ion Zero Po in t Dri ft

AC-magmeter DC-magmeter

% Error

of actualflow rate

5 / 1 1 / 9 85 / 1 0 / 9 8 5 / 1 2 / 9 8 5 / 1 3 / 9 8

1 0

6

1 4

2

- 2

- 6

- 1 0

0

- 1 4




Flow Meter Accuracy







Flow Master




Unsurpassed Performance Comparison

CompanyStandard WW

METER

Accuracy

HighAccuracy

Accuracy at0.5 ft/sec

Accuracy at 2ft/sec

±0.4% ±0.2% ±1.5% ±0.4%

±0.5% ±0.2%* ±3% ±0.75%

±0.5% ±0.25% ±2.5% ±0.5%

±0.5% ±0.2% ±2.0 ±0.7%

±0.5% ±0.25% ±1.0 ±0.5%

±0.35% ±0.2% ±0.5 ±0.35%

±0.5% N/A ±2.2% ±0.5%

±0.5% ±0.2% ±7.8% ±0.65%

±0.5% N/A ±2.0 ±0.5%

Flow Master

Magnetic f low Meter Performance




gAdvantages

No obstructions to the flow

No moving parts to wear or break

Maintenance free

Wide flow range

Worry-free accurate

measurement Debris or solids will not clog the

meter

No head loss

Bi-directional flow

Empty pipe detection

Unaffected by changes indensity and viscosity




Why NOT use Magnetic Flowmeters?

• Magmeters require a conductive process fluid

– No gases or steam

– Entrapped air, foam, or two-phase flow cause errors

– Minimum 5 µSiemens/cm

• Conductance is the reciprocal of Resistance and is measured inSiemens (formerly Mhos)

• 10 Siemens/cm = 0.1 Ohm• 5 µSiemens/cm = 200 kOhm

• Liner temperature limits

• Power consumption of 4-wire device

• Existing Line Flow meter now required



INSTALLATION

Object ives




Identify the best practices recommended for installing magmeter devices

Describe the importance of proper grounding and wiring for remotemount transmitters

Object ives




Best Practices

Sizing

– Review of Instrument Toolkit Materials of Construction

– Ensure liner and electrodes arecompatible with the process

– Gaskets for mounting betweengrounding rings

Handling – Careful handling to prevent damage

Pipe Orientation – Ensure the pipe stays full

– Straight run requirements

Meter Orientation – Electrode plane

Process Connections – Flanged, Wafer, Hygienic/Sanitary

– Wafer mounting kits

Fl T h l S l t i




0 - 0.4 ft/sec Difficult to measure accurately

0.4 - 1.0 ft/sec Measurable in most applications

1.0 - 5.0 ft/sec Measurable, reduced velocityrecommended if fluid contains

abrasive solids

5.0 - 12.0 ft/sec Good flow measurement

13.0 - 25.0 ft/sec Measurable, relatively high

pressure drop will result

Flow Techno logy Select ion Liquid Pipeline Velocities




Sizing

Verify Sizing Results

– Make sure flow rates are acceptable for the sensor line size

– Common for sensor size to match line size

Application Recommended

Minimum

Recommended

Maximum

ConfigurationLimits 0 ft/sec 39.97 ft/sec

Clean Fluid 2 ft/sec 20 ft/sec

Abrasive

Slurry3 ft/sec 10 ft/sec

Non-abrasive

Slurry 5 ft/sec 15 ft/sec




Materials of Construction

Liner Materials

– PTFE, PFA, ETFE,Polyurethane, Neoprene,Linatex

– Temperature Limits

Electrode Materials – SST, Nickel Alloy, Platinum,Tantalum, Titanium

– Grounding Electrode to beused on water applications only

Material Selection Guide – Compatibility and Corrosion

Ratings




Liner Materials

ETFE – Tefzel

– Very Good Chemical Resistance(slightly less than PTFE)

– Excellent Abrasion Resistance(superior to PTFE)

– Liner Bonds to Sensor

– Max Temp = 300°F (149°C)

– Sensor Sizes = 0.5” - 16” (4mm -400mm)

– Recommended for sludge

applications that requirecontinuous submergence

– Recommended for chemical feedMeters




Liner Materials

PFA

– Excellent Chemical Resistance(similar to PTFE)

– Excellent Abrasion Resistance(superior to PTFE)

– Liner Bonds to Sensor and WireMesh

– Recommended for sludgeapplications WAS, RAS , Thickened

– Sensor Sizes = 0.15” - 16” (15mm -300mm)






Liner Materials

Neoprene

– Good Abrasion Resistance

– Good Chemical Resistance

– Max Temp = 185°F (85°C)

– Sensor Sizes = 1.5” and up (40mmand up)

– Softer, Rounded Edges into Sensor

– Used when temps are too high for poly or when some chemicals arepresent

– Recommended for use with saltwater and in O&G water applications(since hydrocarbon carryover iscommon)




Electrode Materials

316L Stainless Steel

– Good corrosion resistance – Good abrasion resistance

Nickel Alloy 276 (Hastelloy C-276)

– Improved corrosion resistanceover 316L SST

– Good abrasion resistance

– Recommended for slurryapplications with a highpercentage of solids

Tantalum

– Excellent corrosion resistance

– Excellent for hydrochloric acid – Do not use in caustic applications

(or applications with CIP)

– Avoid Abrasive Applications

Titanium

– Good chemical resistance – Excellent Abrasion resistance

– Good in caustic applications

80%Platinum - 20%Iridium

– Excellent corrosion resistance

– Good Abrasion resistance

Other material options available

– Consult Factory




Handl ing

Lifting

– 3-Inch and larger sensors have liftinglugs

End caps

– Prevent liner damage

– Prevent PTFE flare

– Only remove

immediately beforeinstallation




• Vertical flow up is best practice

– Ensures electrodes are always covered

– Sufficient back pressure

• Horizontal flow is acceptable

– Electrodes must be covered

• Vertical down is least desirable

– Electrodes not always covered

– Insufficient back pressure may causeprocess noise on electrodes

Pipe Orientation





Invert to keep primary full

Flow Techno logy Select ion Any Flow meters – Piping Requirements





NO!

BEST GOOD

(Up Elbow

Preferred)

NO! Straight Run Required

Flow Techno logy Select ion Most Flow meters – Installation





Flow Techno logy Select ion Magnetic Flow meters – Piping Requirements

90oElbow 5 None

Tee 5 None

Reducer None None < 8o

Control Valve 10 2

Check Valve 10 None

Butterfly Valve 10 2

Gate Valve None None Fully open

Pump 10 None

Configuration Upstream Downstream Comments

Type Pipe dia. Pipe dia.




Straight Run Requirements

• 5 pipe diameters upstream and 2 pipe diameters

downstream – Measured from the measurement electrodes (center of the sensor)

• Distorted flow profiles will cause small shifts usually <2.0%




Meter Orientation

The sensor should be mounted in a position that

ensures the electrodes are covered by the processfluid

– Avoid false empty pipe detection caused by air pockets atthe top of the pipe

– Some sensors have a 45° offset

built in for common mountingpositions

Flow arrow should point inthe flow direction

– Can be used as a bi-directional flowmeter

– Reverse Flow detection can be turned on or off

Process Connections




Process ConnectionsFlanged Sensors

Flanged sensors are bolted to process flanges

– Gaskets are user supplied

• Metallic or spiral-wound gaskets can damage the liner

– Follow bolt torque specifications in the manual

Process Connections




ocess Co ect o sWafer Sensors

Wafer sensors are bolted between process flanges

– Gaskets are user supplied

• Metallic or spiral-wound gaskets can damage the liner

– Centering alignment/spacer rings are supplied at no charge

– Studs, nuts, and washers are available as options

Spacer Ring

Wafer Sensors




Wafer SensorsCentering Alignment Rings

• Alignment rings are critical for accurate and reliable

operation – 0.15” to 1” (4 mm to 25mm) meters have studs that mount

through the meter body

– 1.5” to 8” (40mm to 200mm) meters have centering alignmentrings/spacer rings which are used for positioning




Grounding

• Two types of grounding

– 1. Earth Ground

• Safety

• Establishes low noise environment in sensor

– 2. Process Reference Ground (connect through terminals 17

and ground)• Sensor at same potential as the process fluid

• Established by one of four methods

– Grounding straps

– Grounding electrode – Grounding ring(s)

– Lining protector(s)

Process Reference Ground




Process Reference Ground Ground ing Methods

Mostcommon

Ground OptionConductivityRequirement

Process Piping Material

Relative Price Notes

Conductive (MetalPipe)

Non-conductive(Plastic, etc) Conductive Lined

Grounding Straps 5 uS NA NA No ChargeProvided with every E-series Mag

Tube

GroundingElectrode

100 uS LowLeast Expensive option, provides

convenient grounding for non-conductive and lined pipe applications

GroundRings

5 uS High Provides best ground for non-

conductive and lined pipe applications

Lining Protectors 5 uS HighestMost expensive, pro tects leading edgefrom wear in tough slurry applications

Grounding Methods




g- Ground Straps

Ground Straps

– Connected toconductive pipe

– Most common

method

Grounding Methods




g- Ground Rings/L in ing Protectors

Ground Rings/LiningProtectors

– Connected groundstraps

– Continue connection topipe if conductive

Grounding Methods




g- Ground Elect rode

Ground Electrode

– Only Earth Ground isrequired

– Requires minimum

conductivity of 100µS/cm

– Not recommended for use in plastic pipe or

electrolytic applications – Potential for sludge to

coat




Remote Mount Transmitters

Require additional wiring between transmitter and

sensor

Remote Moun t Transm it ters




Remote Moun t Transm it ters Wiring Preparat ion

Up to 1”

Limit the amount of exposed (unshielded) wire at

termination points

Remote Mount Transm it ters




Electrode (+)Electrode (-)Shield (groundreference)

ShieldCoil (-)Coil (+)

Wir ing Connect ions

4-20 mA Output (+)4-20 mA Output (-)

Power 90 - 250 VAC

or 12 - 42 VDC

Maximum LengthE-Series: 1000 ft100 ftCombo Cable:330 ft





Conduits

The electrode and coil drive cables can be run in the

same conduit – Must have a dedicated conduit for each sensor and

transmitter

WRONG!





Correct!

Conduits

Correct conduit configuration for two separate

systems

Review Questions




Review Questions

Earth Ground, Process Reference Ground

Ground Straps, Ground Rings, Ground Electrode,Lining Protectors

False: Coil Drive = 14 AWG, Signal = 20 AWG

• What are the two types of grounding required for amagmeter system?

• What are the four possible options for providing a processreference ground?

• True/False: The coil drive cable and electrode signal cableshould be the same gauge cable.



TROUBLESHOOTING

Object ives




Name some of the most common problems that occur in magneticflow meter installations

List some of the top causes for common problems

Understand methods and tools used for basic troubleshooting

Object ives

C M t P bl




Common Magmeter Problems

Bad zero

– System reads flow when thereis no flow

Reads an unexpected flow

– Reverse flow

– Unstable flow – No flow

Reads inaccurate flow

– Higher than expected

– Lower than expected



R di hi h th t d




360.0

GPM

327.5

295.0

262.5

230.0

I . ,

TimeSeries

aut8703.dat

01/05/96

422-FX-226-AUTO

PRISCREEN REJFLOW

2560 5 12 769 1025

Mean =300.373 2Sig = 21.8 (7.26%)

Sec

Readings higher than expected

Moisture in terminal block area

Configuration Errors

– Incorrect sensor line size – Incorrect Analog or Pulse

output range

– Incorrect calibration number

– Control system configured

incorrectly

System Upsets

Moisture in the

Terminal Block orSensor Housing

R di l th t d




Readings lower than expected Configuration Errors

– Incorrect sensor line size – Incorrect Analog or Pulse

output range

– Incorrect calibration number

– Control system configured

incorrectly Sensor Faults

– Shorted/Open Coils

– Shorted/Open Electrode(s)

– Moisture in terminal block or

coil housing Process Issues

– Low conductivity

– Coated Electrode(s)

Moisture in the

Terminal Block orSensor Housing

Reading an unexpected flow rate




Reading an unexpected flow rate Reverse Flow

– Installed backwards – Wires reversed

Unstable Flow

– Bad wiring

– Slurry or high solids content

– Entrained air/gas bubbles

– Chemical reaction or chemicaladditives

No Flow

– Transmitter/Sensor faults – No conductivity

– Coated Electrode(s)

Magmeter Troubleshooting Procedure




Work form easiest to hardest

– Transmitter → Wiring → Sensor → Process

Magmeter Troubleshooting Procedure

Transmitter Troubleshooting




Transmitter Troubleshooting

Check transmitter status for error messages

Verify basic configuration parameters

– Calibration Number, Line Size, Flow Units, Range Values

– Pulse Output Factor if using Pulse Output

Operation with control system

– Loop Tests (Analog and Pulse)

Reference Calibration Standard

– Similar to attaching a “perfect” sensor to the transmitter

– Excellent for troubleshooting

– Works on all transmitters

– Spare electronics

– Replace with known good electronics

Wiring Troubleshooting




Wiring Troubleshooting

Signal and Coil Drive must be

twisted / shielded pairs Combination Cable must be

Rosemount Proprietary

Shields must be connected at

both ends Separate conduit each

magmeter system

– Signal and Coil Drive can be insame conduit

Strip back cable 1”

Run known goodwire

Sensor Troubleshooting




Sensor Troubleshooting

Visual Inspection

– Installation – Terminal block

– Process connections

– Process Ground

Manual Sensor Tests

– Coil continuity and insulation – Electrode continuity and

insulation

– Shield continuity to case

Required Tools

– DVM (all tests for sensor out of line)

– LCR Meter (required for electrode measurements if sensor is full of process fluid)

Sensor Troubleshooting – Full




DVM for Coil Tests

– 1 to 2 (Continuity of Coil) – 1 to GND (Insulation of Coil to

ground)

– 2 to GND (Optional, should besame as 1 to GND)

– 17 to Ground Screw (Continuity

of shield to case)

LCR for Electrode Tests

– 17 to 18 (Continuity of frontelectrode to ground)

– 17 to 19 (Continuity of back

electrode to ground) – 18 to 19 (Continuity of electrode to

electrode)

Full

1 2 18 1917

Sensor Troubleshooting – Empty and Installed




Empty and Installed

DVM for All Tests

– 1 to 2 (Continuity of Coil) – 1 to GND (Insulation of Coil to

ground)

– 2 to GND (Optional, should besame as 1 to GND)

– 17 to Ground Screw (Continuity

of shield to case)

– 17 to 18 (Insulation of frontelectrode to ground)

– 17 to 19 (Insulation of backelectrode to ground)

– 18 to 19(Insulation of electrode

to electrode)

Moisture in pipe can causefalse electrode short readings

Conductive coating can causefalse electrode short readings

1 2 18 1917

Process Troubleshooting




Process Troubleshooting

The minimum conductivity is 5 µS/cm

– Hydrocarbons generally too low in conductivity

– Non-conductive fluid mixed with conductive may work(water & glycol)

• Dependent upon % and homogeneous mix

Fluids with components that coat electrodes mayinterfere with the electrode measurement signal

– Oil, sewage at low flow rates, corrosion inhibitors

Solids, chemical additions, or entrained air can

create noisy readings

Electrolytic processes or cathodic protectionsystems can interfere with readings



Meter Verif ication

SMART Meter Verif ic ation Greatly Reduces Cal ibrat ion Veri f icat ion Cos ts




Slide 97

I Would L ike to Veri fy the Magmeter Cal ibrat ion

Without Removing It From The Line Or Using Extra Equipment .

It Would Reduce Maintenance Time and Cost.

Verifying mag calibration historically

involved removing the flowmeter from theline or using extra equipment

SMART™ Meter Verification Diagnosticprovides calibration verification withoutremoving the product from the line or requiring the purchase of extra

equipment

Historically Verifying Meters has been time-consuming and forced shutdown




Slide 98

consuming and forced shutdown

Typical Meter Verification Capabilities

Trip to field

Technical knowledge andExtra equipment

No formal report

No deviation values

More than 120 minutes

May require a processshutdownMust shutdown,

remove meter

from the line, pay

for proving.

Prover External

Equipment

Meter Verification Theory of Operation




Slide 99

A baseline signature of the

magnetic field is taken at thetime of factory calibration

– Signature is independent of temperature and flow-rate

– Signature (and calibration)will change if there is amechanical shift of the coilsover time due to vibration,

thermal cycling, etc

Meter Verification Theory of Operation



Diagnos t ic/Veri f icat ion Measurements




Slide 101

Sensor

Precision Measurements:

– Coil Inductance

– Coil Resistance

– Electrode Impedance

– Electrode Voltage

Fingerprint stored inside the

sensor Transmitter self-checks the sensor

based on technology

Measurements:Elec. R E1: 0.919 kElec. R E2: 1.855 k

Elec. C E1: 100000.094 nFElec. C E2: 100000.094 nF

DC Back Off V: 0.007 VCoil & Cable R: 48.43Coil L: 41.78 mH

Sensor L Shift: 0.53%TX Av. Gain Shift: 0.06%TX Av. Gain Value: 110

Continuous SMART Meter Verification isalways running




Slide 102

y g

Continuous Meter Verification and AnalogLoop Verification can be found here

Magnetic Flow Meter




Slide 103

Standard Diagnostic functions:

Electrode coating

Electrode short circuit

Empty pipe / partially full

Extended Diagnostic functions (in preparation):

Gas bubbles detection

Signal noise indication

Electrode corrosion

Low conductivity detection

Liner damage

Partially full pipe

Veri f icat ion Systems Verification System – Calibration Certificate




Slide 104

Equipment Certification

Verification Certainty Options1. Fingerprinted by

manufacturer• 99% certainty calibration

is within ±0.2%2. Retrofitted in the Field• 98% certainty calibration

is within ±0.2%

Independent Testing

http://www.nist.gov/





Specify or replace existing Flow Meters with a Meterthat has the coil drive power to read low flow rates.

Apply the proper electrode and liner material for your

application.

Install the meter in a location ensuring that the meter is

always full and is away from obstructions.Specify a meter with diagnostics that will continuously

monitor your meter and offer solutions to fix noted

issues. If the meter is below grade ensure that the

electronics or meter housing is NEMA 6P

Do this and you should never need to reference this

presentation

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Flow Meter Technology

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