yokogawa corporation of america copyright © yokogawa electric corporation digital sensor technology

Yokogawa Corporation of America

Copyright © Yokogawa Electric Corporation

Digital Sensor Technology

Copyright © Yokogawa Electric

DPharp DIGITAL FAMILY™

Draft Range and Differential Pressure

Low Flow w/Integral Orifice

Differential and Gauge

Pressure w/RemoteDiaphragm Seals

Liquid Levelw//Flush and/or Extended

Diaphragm Seals

Absolute and Gauge Pressure

High Static andGauge Pressure


Variable CapacitancePressure Sensor

Pressure Portwith Fill Fluid

Electrodes to Sensor

HermeticGlass Seal

Metallic Capacitance Sensor


Piezoresistance Sensor


Vacuum

Digital Sensor Design


Compression BridgeTension Bridge

2. Pressure is appliedto silicon substrate

1. Two ‘H’ shaped bridges resonating

@ 90 kHz are located in a silicon substrate

3. Due to their position and exact

depth on the substrate one bridge goes into tension and the other

into compression

4. As pressure is appliedchanges from 90-110 kHz and the compression bridge fromfrequency of the tension bridge90-70 kHz.

5. To obtain differential outputthe microprocessor simply countsthe change in bridge frequencies

depth

110

90

70

kHz

Resonant Silicon Sensor Bi-directional Operation


0

20

40

60

80

100

120

0 50 100 150 200

fc

fr

Resonant Sensor Differential Frequency Output of a Resonant Sensor

40 KHz

Pressure

Pressure (inH20)

Freq.(kHZ)

naturalresonant frequency


Resonant Sensor Technology Advantages

Inherently Digital Output– Frequency Signal– No A/D Conversion Errors– Pressure Transmitter Reranging Errors

Eliminated

Large Change in Output – Excellent Resolution – Frequency Counter Resolution > 18 Bit ( 1:262 K

)– Frequency Counter TPE < 100 ppm

Silicon Resonator– Minimal Hysteresis– Minimal Temperature Coefficient


0.1

1

10

100

1000

10000

100000

@ 20:1 @ 10:1 @ URL

Cap.

Piezo R.

Res. Si

Signal Output (Logarithmic scale)

Turndown

Sensor O/P Change Vs Turndown


% E J A 1 1 0 D i f f C a p .0 0 . 0 0 5 0 . 0 2 5

2 5 0 . 0 1 5 - 0 . 0 1 25 0 0 . 0 0 3 - 0 . 0 1 87 5 0 . 0 0 8 - 0 . 0 4 0

1 0 0 0 . 0 0 0 - 0 . 0 4 07 5 0 . 0 0 8 - 0 . 0 1 35 0 0 . 0 0 5 - 0 . 0 0 52 5 0 . 0 1 0 - 0 . 0 1 70 0 . 0 0 5 0 . 0 0 0

A v e 0 . 0 0 3 - 0 . 0 1 3

R e f e r e n c e A c c u r a c y 0 t o 2 0 0 " H 2 O

- 0 . 0 5 0

- 0 . 0 4 0

- 0 . 0 3 0

- 0 . 0 2 0

- 0 . 0 1 0

0 . 0 0 0

0 . 0 1 0

0 . 0 2 0

0 . 0 3 0

0 . 0 4 0

0 . 0 5 0

0 2 5 5 0 7 5 1 0 0 1 2 5

% I n p u t

%Erro

r

Outp

ut

S u p e r i o r R eS u p e r i o r R e -- r a n g e P e r f o r m a n c er a n g e P e r f o r m a n c eE J A s e r i e s v s . ‘ f r e e f l o a t i n g ’ d i f f e r e n t i a l c a p a c i t a n c e

C a p a c it a n c e

E J A S e r ie s

u p s c a le / d o w n s c a le o u tp u t s


A/D D/ACPU

4-20 mA TRIM

Analog Signal From Sensor

DigitalConversion To CPU

AnalogSignalOut

Digital Signal ToConverter

Improved I/O Characteristics -Eliminate ‘Trim’

Analog signal from sensor is converted to digital signal for CPU processing.

CPU samples input and performs linearization and temperature/pressure characterizations.

CPU output is converted to analog signal for 4-20 mA.Errors between CPU input and D/A converter output result due to poor

resolution between signals .4-20 mA ‘TRIM’ is required as a result.


DPharp Fieldbus Sensor

WorkstationWorkstation

Controller

Fieldbus InterfaceFieldbus Interface

Future Field Control System (FCS)

4-20 mA

Today’sSensorScheme

Other field devices

Fieldbus eliminatesthe need for I/O

DigitalSensorScheme

DPharp eliminates the need for A/D

A/D A/D

FIELDBUS

D/AD/A

MicroprocessorMicroprocessor

A/DA/DA/D

SensorSensor


A/DA/DA/D

SensorSensor

Fieldbus InterfaceFieldbus Interface


A/DSensorSensor

WorkstationWorkstation

Analog SensorScheme

DCS vs. Field Control System


DPharp EJA Series CapsuleExploded View

1-Piece Capsule BodyConstruction

Overpressure Diaphragm Low-volume

Insert


Superior Transmitter Design

Teflon CoatedS.S. Gasket

Overpressure Diaphragm

Digital harpSensor

Universal EJA Electronics


Over Pressure Effects are EliminatedOver Pressure Effects are Eliminated

CapsuleBody

Low-volume Insert

OverpressureDiaphragm

ElectronBeam Weld

45o

3

2

1WELDAREA

WELD

Convolutions


Calibration Shift with 2000 PSI Over-range

0 to 200 " H2O Span

-1.000

-0.500

0.000

0.500

1.000

0 25 50 75 100

% Input

%C

ha

ng

e

Ou

tpu

t

Superior Over-pressure PerformanceEJA Series vs. ‘Free Floating’ Differential Capacitance

Diff. Capacitance

EJA Series

Zero Shift

upscale/down scale outputs


GlassIsolator

Chip

Header

HP Fluid Pressure

LP Fluid Pressure

CapsuleBody

Thermally Isolated SensorAway From the Process

1. “harp’ sensor located in neckof capsule body

isolated from process

IsolationDiaphragm(s) 2. HP and LP pressures

are transferred from theisolation diaphragm tothe sensor via internally machined low volume fluid passages.

Process temperature isolation Process pressure isolation

P1

LP= P2

HP= P1


Standard PerformanceBenefits of the harp Technology

0.075% AccuracyHigh accuracy, High resolution

No overpressure effect0.03% URL per 2300 psi

Five Year Stability0.1% URL per 5 years

Fewer Calibrations100:1 TurndownIndustry Canada Approval


Influences on Stability

Ambient temperature

Differential pressure cycles

Static pressure cycles

Overpressure events

Hysteresis is the root cause of many drift related symptoms


Competitive stability guarantyStatic pressure (PSI)

Temperature(deg F)

Over pressure (PSI)

185-40

2300

2300

Limit conditions to meet their stability specification!


Yokogawa’s stability guaranty

Static pressure (PSI)

Temperature(deg F)

Over pressure (PSI)

185-40

2300

2300

Under all conditions


YOKOGAWA

Competitor ‘A’

Competitor ‘B’

Force Balance

Pneumatic

Capacitance

Analog

Analog

Piezoresistive

Analog

Silicon Resonant

Digital

1960’s 1970’s 1980’s 1990’s

Analog

Digital Paradigms - 80’s & 90’s Sensor History by Leading Suppliers

Future


EJA110AEJA110ADifferential Pressure Transmitter

Accuracy: ±0.075%

Stability: ±0.1% URL 5 Years

Turndown: 100:1

Capsule design virtually eliminates hysteresis

Span: from 2 to 2000 inH2O

Warranty: 3 years (2-year on-site + 1 year return to factory)


EJA115EJA115Low flow transmitter with integral flow orifice assembly

Integral orifice assembly

Low flow customizing for improved control

Capsule design virtually eliminates hysteresis

Span: from 4 to 830 inH2O (10 to 20339 scfh)



EJA118N, W, &YEJA118N, W, &YDifferential pressure with remote flush, extended or combination diaphragm seals

Auto level set-up eliminates elevation and suppression calculations

3 in. 150-600 lb. flush diaphragm configuration

4 in. 150-300 lb. extended diaphragm configuration

Combination of flush & extended diaphragms

Span: from 10 to 2000 inH2O



EJA220AEJA220A Flange mounted liquid level transmitter (extended diaphragm)

Auto level set-up eliminates elevation and suppression calculations

4 in. 150-300 lb. extended diaphragm configuration

Measurement ranges: from 10 to 2000 psi



EJA530/510ALow Cost Gauge/Absolute pressure transmitter

Key Features1/2” NPT Male or Female

bottom connectAllows various seals and Tri-clamp connectionAccuracy. 20% Span.075 % HAC optionCompetitively Priced HARP Pressure SensorMeasurement Ranges from 1.5 psi

to 10,000psi



Diagnostics and Diagnostics and MaintenanceMaintenance


Multi-Sensing With Diagnostics ‘Event’ MemoryMulti-Sensing With Diagnostics ‘Event’ MemoryTransmitter health monitoring capability

Thermistor Thermistor harp sensor

Amp. Temp. Caps. Temp. Line Press. Diff. Press.

‘Event’ Buffer

Diagnostics

Sensor Function Benefit Memory

Measured Variable Trip Point Diagnostic

Static Pressure LRVHRV

Upset, Excessive Flow,Plugging

Gage Pressure LRVHRV

Upset, High/Low Pressure,Plugging

Capsule Temp -50 to 130C High/Low Process Temp

Amplifier Temp -50 to 95C High/Low Ambient Temp


Bi Directional FlowBi Directional FlowReduced design costs

User calibrates 0 to 100” wc 12 - 20mA Forward Flow / 4 - 12 mA Reverse Flow

Eliminates the need for 2 transmitters Simplifies setup All custom flow functions apply

4 mA

20 mA4-20 mA Output

Linear Square Root

NormalReverse

Conventional type

ForNormal

Flow

ForReverse

Flow

H L L H

EJA

H L

E30: Bi Dire Mode


Electronic Re-PipingElectronic Re-PipingStart-up and maintenance costs

D45: H/L SWAPD45: H/L SWAP

Reduces start up time by allowing the user to correct for piping mistakes in the fielduntil it’s cost-effective to re-pipe

EJA

H L


Flow CustomizingFlow Customizing

D10: Low Cut and D11: D10: Low Cut and D11: ModeMode

Drop Out mode adds stability to the lower 20% flow.

50

20

050(%)

Input

Low Cut @ 20%

(%) (%)

50

20

0 50(%)

Low Cut @ 20%

Input

Low Cut Mode “LINEAR” Low Cut Mode “ZERO”


EJA with Auto Level

Eliminates physics involved with level setupFlat bench zero and spanActual height of fluid is not required for installation and calibration of tank levelZero offset does not affect spanAccuracy of Instrument not affectedSliding window effect with EJA


Local site glass adjustmentto any known point

No re-calibration

No need for hand-held

Smart local field adjustmentsSmart local field adjustmentsPrecision 0.01% digital encoder

Digital encoder with ramp function

15%

sight glass


Digital Sensor Technology

The Future is here today !

Digital harpSensor


Visit us on our website

WWW.US.Yokogawa.COM



Thank You

yokogawa corporation of america copyright © yokogawa electric corporation digital sensor technology

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