Internship Report FFC

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T

TE C H N OE C H N O

Dawood University of Engineering & Tech

Internship

Report

M

UHAMMAD

H

A

S

A

N

Seat No: D_10_ES_1050

Final Year ( Electronics Engineering)

Dawood University of Engineering & Techn

Internship Duration ( 14 February 2013 to

Submitted to

Submitted to: Technical Training

: Technical Training

(TTC)

(TTC) Mirpur Mathailo

Mirpur Mathailo

D D A AWWOOOODD UUN I V E R S I T Y O FN I V E R S I T Y O F EEN G I NN G I N O OGGYY KK A ARRAACCHHII nology nology o ologylogy 7 March 2013) 7 March 2013)

enter

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Acknowledg

Ultimately, I have completed my

six weeks. First and foremost, th

report. Without Your Wil

I would never forget to mention

of this project, and helped me,

books for assi

I would like to take this

I would like to take this oppo

oppo

Mr.Anjum Beig

Mr.Anjum Beig who have given

who have given

pp

I am also grateful to my coordi

who were a great help for me by

Finally, I

Mr. Aftab Ahmed Mazari

for

Without your willingness, sugge

I am very much thankful to FFC

with industrial practical knowled

about all the kind panel boardm

Control

At last, I can say that my work

without

PREFACE

The purpose of this report is to exp The purpose of this report is to exp Fertilizer Company Mirpur Mathelo Fertilizer Company Mirpur Mathelo MM internship program. The repor MM internship program. The repor environment

environment, successes , successes and shortcand shortc assigned to him by the coordinator assigned to him by the coordinator shortcomings, successes ,observati shortcomings, successes ,observati

Dawood University of Engineering & T Dawood University of Engineering & T

ment

report with all the hard work which I have

report with all the hard work which I have been

been

ank you Almighty Allah for giving me the

ank you Almighty Allah for giving me the strengt

strengt

llingness I would not have

llingness I would not have been able to complete

been able to complete

the names, which played a great role in the

the names, which played a great role in the succe

succe

whenever I required any guidance from them, pr

tance and gave me ideas on different thoughts.

tunity to express my deepest gratitude to

tunity to express my deepest gratitude to Mr.A

Mr.A

me their constant

me their constant encouragemen

encouragement constructive a

t constructive a

atience in monitoring my progress.

ators

ators Mr. Muhammad Fahad Sayeed

Mr. Muhammad Fahad Sayeed

&

& Mr. Um

Mr. Um

monitoring my learning and helping me understan

numerous interactions.

ould like to extend my sincere gratitude to

his helpful nature and valuable guidance provided

stions and insights, this project would not have b

which provided me a chance to integrate my clas

ge in a 6

ge in a 6 weeks internship program. I would not f

weeks internship program. I would not f

n and operators who had been a very useful guid

Room and on the

Room and on the plant site, respectively.

plant site, respectively.

was just an effort but wouldn’t have been an eff

the support of all

the support of all acknowledged people.

acknowledged people.

lain what I did and

lain what I did and learned during my internlearned during my internship peship pe . The report is also a requirement for the partial ful . The report is also a requirement for the partial ful t focuses primarily on the assignments handled, wo t focuses primarily on the assignments handled, wo o

omings that the intern did encounter when handlinmings that the intern did encounter when handlin .Because the various parts of the

.Because the various parts of the report reflect thereport reflect the ns and comments, it would be imperative that the ns and comments, it would be imperative that the

chnology chnology

oing for the last

to finish up this

ny work.

ssful completion

ovided me with

if JAMAL

&

vises and their

air Akbar Khan

d the process in

time and again.

een completed.

room knowledge

rget to mention

e in the Central

ort discernibly

riod with the Fauji riod with the Fauji fillment fillment of of FFCFFC rking rking g various tasks g various tasks intern’s intern’s

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P a g e P a g e | 3| 3 recommendat

recommendations are also ions are also given. Tgiven. T recommendat

recommendations on ions on the internshithe internshi vehicle to the improvement of the i vehicle to the improvement of the i

INTRODUCTI

For an agricultural country like Paki For an agricultural country like Paki Fertilizer Company (FFC)

Fertilizer Company (FFC) was incwas inc self - sufficiency in fertilizer producti self - sufficiency in fertilizer producti (a leading charitable trust in

(a leading charitable trust in PakistPakist is the leading urea producing c is the leading urea producing c commenced commercial productio commenced commercial productio plant of the FFC is located at GOTH plant of the FFC is located at GOTH After the excellent performance a After the excellent performance a second plant at the same place in second plant at the same place in plant is called the EXPANSION plant is called the EXPANSION 635,000 metric tons of urea. 635,000 metric tons of urea.

In the year 2002, FFC acquired e In the year 2002, FFC acquired e Mirpur Mathelo, District Ghottki fr Mirpur Mathelo, District Ghottki fr process of the Government of Pak process of the Government of Pak urea which has been revamped to urea which has been revamped to

SAFETY

TRAI

FFC produces about 60 % of m

only result in decrease of compa

market. This may affect the cou

followed by price hiking.

FFC ensures safe work environ

all personnel on plant. As per th

personnel on plant receive safet

responsibilities

The training comprised of:

Dawood University of Engineering & T Dawood University of Engineering & T herefore the report gives a number of comments a herefore the report gives a number of comments a program. It is hoped that this report would serve program. It is hoped that this report would serve internship program.

internship program.

N TO FFC

stan, Urea carries a paramount importance. Keepin stan, Urea carries a paramount importance. Keepin rporated in 1978 as a private limited company with rporated in 1978 as a private limited company with ion in the country. This was a joint venture between ion in the country. This was a joint venture between

n

n) and) and Haldor Topsoe A/SHaldor Topsoe A/S of of DenmarkDenmark.Fauji Ferti.Fauji Ferti ompany in the Pakistan, with brand name ompany in the Pakistan, with brand name “S“S

of urea in 1982 with annual capacity of 570,000 of urea in 1982 with annual capacity of 570,000 MACHI in SADIQABAD.

MACHI in SADIQABAD.

nd the successful achievements of the first plant, nd the successful achievements of the first plant, the year 1993. First plant is called the BASE UNI the year 1993. First plant is called the BASE UNI UNIT. This enhanced Production capacity with a UNIT. This enhanced Production capacity with a

Pak Saudi Fertilizers Limited (PSFL)

Pak Saudi Fertilizers Limited (PSFL) Urea PlaUrea Pla om National Fertilizer Corporation (NFC) through om National Fertilizer Corporation (NFC) through istan. It has annual production capacity of 574,00 istan. It has annual production capacity of 574,00

18,000 metric tons urea in 200 18,000 metric tons urea in 200

ING

rket’s urea production. Not preparing for plant

ny production and sale but also in shortage of f

try’s agriculture growth and thus shortage of fo

ent by providing safety training to

company policy all news

training prior taking charge of their

chnology chnology d d s a cardinal s a cardinal this in view this in view FaujiFauji a vision to acquire a vision to acquire Fauji Foundation Fauji Foundation ilizer Company Ltd ilizer Company Ltd NA UREA” NA UREA”.FFC.FFC metric tons. First metric tons. First

FFC installed the FFC installed the T and the second T and the second nnual capacity of nnual capacity of

t situated at t situated at privatization privatization metric tons metric tons

afety may not

ertilizer in

od for public

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

Importance of Safety at



Use of Personal Protec



Use of Fire Extinguishe



Ammonia Disaster

PERSONAL PROTECTIVE E

Personal protective equipment (P.P Personal protective equipment (P.P regarded as a substitute for safe w regarded as a substitute for safe w personal protective equipment is as personal protective equipment is as

•

• Safety HelmetSafety Helmet •

• Safety boot/shoesSafety boot/shoes •

• Escape respirator (Half FacEscape respirator (Half Fac •

• Ear protection (designatedEar protection (designated •

• Safety Spectacles.Safety Spectacles.

The correct use, care an The correct use, care an responsibility of each in responsibility of each in

Plant

ive Equipment

rs

UIPMENT

.E) must not be .E) must not be

rking practices. Minimum rking practices. Minimum

follow. follow. e Mask) e Mask) areas) areas)

“Your life is preci “Your life is preci

regular cleaning of the above equipment is the regular cleaning of the above equipment is the ividual. ividual. chnology chnology ous” ous”

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INSTUMENTAT

TOPIC



Introduction to inst



Sample Control Lo



Introduction to Doc



Types of instrumen



Introduction to Intri

CO

ENGR.

ENGR. MU

MU

INSTRUMENTATION

Instrumentation is the art of measur Instrumentation is the art of measur temperature to name a few and sup temperature to name a few and sup output signals are standard signal a output signals are standard signal a alarms or automatic control. There alarms or automatic control. There plant are the 4-20 mAmps Electroni plant are the 4-20 mAmps Electroni

CONTROL TECHNOLOGY

Control of the processes in the plan Control of the processes in the plan water in the boilers to act as a heat water in the boilers to act as a heat the boilers towards the turbine. The the boilers towards the turbine. The transport pressure is another critical transport pressure is another critical

ON & CONTROL ORIEN

umentation & control.

p.

umentation, Drawings, P & I’s.

s.

nsic Safety.

-ORDINATOR

AMMAD FAHAD SAE

A

A MMAD FAHAD SAE

MMAD FAHAD SAE

AMMAD FAHAD SAEE

E

ing the value of some plant parameter Pressure, flo ing the value of some plant parameter Pressure, flo plying a signal that is proportional to the measured plying a signal that is proportional to the measured nd can then be processed by other equipment to pr nd can then be processed by other equipment to pr re a number of standard signals; however, those m re a number of standard signals; however, those m c signal and 3-15 psi pneumatic signal.

c signal and 3-15 psi pneumatic signal.

t is an essential part of the plant operation. There m t is an essential part of the plant operation. There m sink for the reactor but there must not be water flow sink for the reactor but there must not be water flow level of the boiler must be kept within a certain rang level of the boiler must be kept within a certain rang l parameter that must be controlled. If it is too high t l parameter that must be controlled. If it is too high t

chnology chnology

ATION

, level or , level or arameter. The arameter. The vide indication, vide indication, ost common in the ost common in the

ust be enough ust be enough ing out the top of ing out the top of

e. The heat e. The heat

e system will e system will

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burst, if it is too low the water will b burst, if it is too low the water will b cool the fuel.

cool the fuel.

The usual objective of control theor The usual objective of control theor controller that result in system stabi controller that result in system stabi it.

it.

The first automatic feedback control The first automatic feedback control developed in 1769 for controlling th developed in 1769 for controlling th

CONTROL LOOP

A control system consists of subsys A control system consists of subsys



A

si

mp

le

co

nt

ro

l

lo

o

A simple closed loop control re A simple closed loop control re process or system to a controll process or system to a controll produces the corresponding ou produces the corresponding ou Feedback control is a fundamental Feedback control is a fundamental pleasant task when the auto respon pleasant task when the auto respon and brakes, which utilize hydraulic and brakes, which utilize hydraulic wheel.

wheel.

A simple block diag A simple block diag

Dawood University of Engineering & T Dawood University of Engineering & T il. Either condition impairs the ability of the heat tra il. Either condition impairs the ability of the heat tra

is to calculate solutions for the proper corrective a is to calculate solutions for the proper corrective a lity, that is, the system will hold the set point and no lity, that is, the system will hold the set point and no

ller used in an industrial process was James Watt’s ller used in an industrial process was James Watt’s

speed of a steam engine. speed of a steam engine.

tems and plants(processes) assembled to control o tems and plants(processes) assembled to control o

p

q

quires feedback; information sent back direcuires feedback; information sent back direc ler which manipulates it keeping set point in ler which manipulates it keeping set point in

tput to control final control element. tput to control final control element.

act of modern industry and society. Driving an auto act of modern industry and society. Driving an auto ds rapidly to the driver’s commands. Many cars hav ds rapidly to the driver’s commands. Many cars hav mplifiers for amplification of the force to the brakes mplifiers for amplification of the force to the brakes

am of an automobile steering control system is sho am of an automobile steering control system is sho

chnology chnology

sport system to sport system to

tion from the tion from the

oscillate around oscillate around lyball governor, lyball governor, tput of process. tput of process.

tt from thefrom the view and view and obile is a obile is a e power steering e power steering or the steering or the steering n, n,

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The desired course is compared wit The desired course is compared wit of the error .This measurement is o of the error .This measurement is o additional feedback from the feel of additional feedback from the feel of the hand (sensor)

the hand (sensor)

A basic, manually controlled closed A basic, manually controlled closed regulating the level of fluid in a tank regulating the level of fluid in a tank .The input is a reference level of flui .The input is a reference level of flui instructed to maintain.(This referen instructed to maintain.(This referen operator.) The power amplifier is th operator.) The power amplifier is th sensor is visual .The operator comp sensor is visual .The operator comp with the desired level and opens or with the desired level and opens or (actuator), adjusting the fluid flow o (actuator), adjusting the fluid flow o desired level. desired level.

Introduction to Document

P & I's:

Documentation is done to keep the Documentation is done to keep the instruments &

instruments &

Chemical being used in plant. All t Chemical being used in plant. All t industry have their own literature a industry have their own literature a things that they need to use, to re things that they need to use, to re their records collected in files with t their records collected in files with t In industry we keep the records of f In industry we keep the records of f



 History cards (Switches, Tr History cards (Switches, Tr



 Calibration cards.Calibration cards.



 Warehouse Documents whiWarehouse Documents whi Request), MRF (Material Reservati Request), MRF (Material Reservati Voucher),

Voucher), MWR MWR (Maintenance (Maintenance WoWo



 Set point changing formSet point changing form



 Cabinet daily monitoring for Cabinet daily monitoring for



 Power supply load checkinPower supply load checkin



 DCS vibration probe histor DCS vibration probe histor In industries there are some field p In industries there are some field p this purposed designers make draw this purposed designers make draw in those processes. A line diagram in those processes. A line diagram each

each instrument instrument is is called called ProcessProcess

Dawood University of Engineering & T Dawood University of Engineering & T h a measurement of the actual course in order to ge h a measurement of the actual course in order to ge tained by visual and tactile(body movement) feedb tained by visual and tactile(body movement) feedb the steering wheel by

the steering wheel by

loop system for loop system for is shown in Figure is shown in Figure d that the operator is d that the operator is

e is memorized by the e is memorized by the

operator, and the operator, and the ares the actual level ares the actual level closes the valve closes the valve

t, to maintain the t, to maintain the

tion, Drawings,

record of all the things, record of all the things, he departments in the he departments in the

bout their concern things and they go through the bout their concern things and they go through the air or install. Here in instrument department all th air or install. Here in instrument department all th

eir vendor's name and specifications. eir vendor's name and specifications. llowing:

llowing:

nsmitters, Valves, P SV's). nsmitters, Valves, P SV's). ich includes MOR (Manual Order ich includes MOR (Manual Order

n Form), MIV (Material Issue n Form), MIV (Material Issue k Request). k Request). m m etc. etc.

laces where the loops of a system is long Enough laces where the loops of a system is long Enough ings on big Sheets that shows all the process and i ings on big Sheets that shows all the process and i that helps us to understand the whole process in that helps us to understand the whole process in & Instrument diagrams.

& Instrument diagrams.

chnology chnology nerate a measure nerate a measure ck. There is an ck. There is an

literature of all the literature of all the instruments have instruments have o understand .For o understand .For struments involve struments involve cluding function of cluding function of

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TYPES OF INSTRUMENT

Here in FFC MM we use several t Here in FFC MM we use several t to the requirements .The major inst to the requirements .The major inst Transmitters, Thermocouples, E / Transmitters, Thermocouples, E / Recorders, Indicators, Switches, T Recorders, Indicators, Switches, T SOV's, Tachometers. SOV's, Tachometers.

FIEL

TOPIC



Level, Flow, Pressu

instrument being us



Switches (Level, Fl



Float type level indi



Transmitter

s &

I/P’s



SOV’s



Analyzers

CO

E

ENG

NG

Dawood University of Engineering & T Dawood University of Engineering & T pes of instruments that have their specific function pes of instruments that have their specific function uments which we use here are:

uments which we use here are:

P, Speed Probes, Vibration Probes, Pressure ga P, Speed Probes, Vibration Probes, Pressure ga mperature Indicators local, Petitioners’, Pressure s mperature Indicators local, Petitioners’, Pressure s

INSTRUMENTATION

re &Temperature measuring techniq

ed.

w, Temperature & Pressure)

cator

-ORDINATOR

.UMAIR AKBAR

chnology chnology

and use according and use according uges, Controllers, uges, Controllers, itches Analyzers, itches Analyzers,

es

&

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PRESSURE

Pressure is probably one of the mo Pressure is probably one of the mo measurement of steam pressure; fe measurement of steam pressure; fe many more.

many more.

In many ways, pressure is the prim In many ways, pressure is the prim



 Flow (measuring pressureFlow (measuring pressure



 Level (measuring the presLevel (measuring the pres ““Pressure is the force exerted by Pressure is the force exerted by fluid /gas.”

fluid /gas.”

Pressure acts on surface area of ve Pressure acts on surface area of ve Mathematically

Mathematically

Pressure is actually the measurem Pressure is actually the measurem Force = Pressure / Area

Force = Pressure / Area

Pressure scale

Pressure varies depending on altitu Pressure varies depending on altitu measure of pressure is, therefore, r measure of pressure is, therefore, r absolute. Gauge pressure is the uni absolute. Gauge pressure is the uni pressure). A gauge pressure device pressure). A gauge pressure device (i.e., gauge pressure is referenced t (i.e., gauge pressure is referenced t atmospheric pressure with the gaug atmospheric pressure with the gaug atmospheric pressure when comple atmospheric pressure when comple Absolute Pres Absolute Pres

Dawood University of Engineering & T Dawood University of Engineering & T t commonly measured variables in the Power plant. t commonly measured variables in the Power plant. ed water pressure, condenser pressure, lubricating ed water pressure, condenser pressure, lubricating

ry element in many of the process measurement, s ry element in many of the process measurement, s drop across restriction by creating differential press drop across restriction by creating differential press

ure created by vertical fluid column) ure created by vertical fluid column)

fluid or gas and it is transmtted in all directions fluid or gas and it is transmtted in all directions

ssel or chamber in which it is confined. ssel or chamber in which it is confined.

nt of force acting on area of surface. We could repr nt of force acting on area of surface. We could repr

de above sea level, weather pressure fronts and oth de above sea level, weather pressure fronts and oth e

elative and pressure measurements are stated as eilative and pressure measurements are stated as ei t we encounter in everyday work (e.g., tire ratings a t we encounter in everyday work (e.g., tire ratings a will indicate zero pressure when bled down to atm will indicate zero pressure when bled down to atm o atmospheric pressure). Absolute pressure include o atmospheric pressure). Absolute pressure include e pressure. An absolute pressure indicator would in e pressure. An absolute pressure indicator would in tely vented down to atmosphere - it would not indic tely vented down to atmosphere - it would not indic ure = Gauge Pressure + Atmospheric Pressure ure = Gauge Pressure + Atmospheric Pressure

chnology chnology . It includes the . It includes the oil pressure and oil pressure and

ch as: ch as: re) re) throughout the throughout the

sent this as: sent this as:

er conditions. The er conditions. The ther gauge or ther gauge or

e in gauge e in gauge spheric pressure spheric pressure s the effect of s the effect of dicate

dicate

te scale zero. te scale zero.

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PRESSURE MEASURING PRESSURE MEASURING



 BAROMETER:BAROMETER: For measuringFor measuring



 MANOMETER:MANOMETER: An instrumenAn instrumen has three types:

has three types: a) U-shaped Manometer a) U-shaped Manometer b) Inclined Manometer b) Inclined Manometer c) Ring Shaped Manometer c) Ring Shaped Manometer

BOURDON TUBES:

BOURDON TUBES: Bour Bour with oval cross sections. T with oval cross sections. T the inside of the tube. The the inside of the tube. The section forces it to become section forces it to become of the tube ring, the bourd of the tube ring, the bourd the direction of the arrow. the direction of the arrow.



BELOWS

::Bellows typeBellows type membranes that are convol membranes that are convol membrane is attached at o membrane is attached at o instrument. The bellows ele instrument. The bellows ele the arrow when input press the arrow when input press



DIAPHARAM:

A diaphr A diaphr pressure fixture around the pressure fixture around the indication medium is on the indication medium is on the be in the direction of the arr be in the direction of the arr

PRESSURE TRANSMIT

Most pressure transmitters are built Most pressure transmitters are built measuring differential pressure (tha measuring differential pressure (tha pressure input) and therefore, are u pressure input) and therefore, are u cells.

cells.

Capacitance Type

A capacitance cell measures chang A capacitance cell measures chang the capacitance of a capacitor is dir the capacitance of a capacitor is dir metal plates and inversely proportio metal plates and inversely proportio also depends on a characteristic of also depends on a characteristic of

Dawood University of Engineering & Dawood University of Engineering & EVICES

EVICES

atmospheric pressure. atmospheric pressure.

tt that measures pressure in terms of height of a colthat measures pressure in terms of height of a col

on tubes are circular-shaped tubes on tubes are circular-shaped tubes he pressure of the medium acts on he pressure of the medium acts on outward pressure on the oval cross outward pressure on the oval cross rounded. Because of the curvature rounded. Because of the curvature on tube then bends as indicated in on tube then bends as indicated in

lements are constructed of tubular lements are constructed of tubular uted around the circumference. The uted around the circumference. The

e end to the source and at the other end to an indic e end to the source and at the other end to an indic ment can provide a long range of motion (stroke) in ment can provide a long range of motion (stroke) in ure is applied.

ure is applied.

gm is a circular-shaped convoluted membrane that gm is a circular-shaped convoluted membrane that circumference. The pressure medium is on one sid circumference. The pressure medium is on one sid other. The deflection that is created by pressure in other. The deflection that is created by pressure in ow indicated.

ow indicated.

ERS

around the pressure capsule concept. They are us around the pressure capsule concept. They are us t is, the Note difference between a high pressure in t is, the Note difference between a high pressure in sually called DP transmitters or DP

sually called DP transmitters or DP

ressure Transmitter

es in capacitance. The capacitance of es in capacitance. The capacitance of ectly proportional to the area of the ectly proportional to the area of the nal to the distance between them. It nal to the distance between them. It the insulating material between them. the insulating material between them.

echnology echnology mn of liquid. It mn of liquid. It

ating device or ating device or the direction of the direction of

is attached to the is attached to the and the and the he vessel would he vessel would

ally capable of ally capable of ut and a low ut and a low

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This characteristic, called permittivit This characteristic, called permittivit of the capacitor to store charge. of the capacitor to store charge.

Two capacitors are joined together i Two capacitors are joined together i diaphragm. High and low pressures diaphragm. High and low pressures deflect from high to low pressure si deflect from high to low pressure si capacitors. Thus difference of press capacitors. Thus difference of press

Potentiom

It also works on the similar principle It also works on the similar principle measure pressure instead of capaci measure pressure instead of capaci with a common diaphragm and appl with a common diaphragm and appl Difference of pressure causes diap Difference of pressure causes diap lower pressure side. As a result ne lower pressure side. As a result ne potentiometer changing its resistan potentiometer changing its resistan Thus difference of pressure causes Thus difference of pressure causes resistance. Figure shows a similar resistance. Figure shows a similar produce a constant pressure on on produce a constant pressure on on

Linear Variable diff

LVDT also works on the similar prin LVDT also works on the similar prin pressure. Diaphragm is connected t pressure. Diaphragm is connected t The extension control rod is made The extension control rod is made the movable core of a transformer. the movable core of a transformer. primary and secondary windings of primary and secondary windings of inductance between the two windin inductance between the two windin output voltage proportional to the p output voltage proportional to the p extension.

extension.

FLOW

“The quantity of fluid pas

BASIC FLOW MES

There are various methods used to There are various methods used to nuclear generating station.

nuclear generating station.

Dawood University of Engineering & Dawood University of Engineering & y is a measure of how well the insulating material in y is a measure of how well the insulating material in

C=E A / D C=E A / D

in such a way that they have one plate in common in such a way that they have one plate in common are applied at the two sides of the diaphragm whic are applied at the two sides of the diaphragm whic e. This deflection causes a change in the capacitan e. This deflection causes a change in the capacitan ure is converted into difference of capacitance. ure is converted into difference of capacitance.

tric Pressure Transmitter

but uses a variable resistor to but uses a variable resistor to itance. Two chambers are joined itance. Two chambers are joined lied with high and low pressure. lied with high and low pressure.

ragm to move a little towards ragm to move a little towards dle attached with it, moves over a dle attached with it, moves over a

e between electrical contacts. e between electrical contacts. a corresponding change in the a corresponding change in the ssembly where a spring is used to ssembly where a spring is used to

side of diaphragm. side of diaphragm.

rential Transformer

ciple for measuring differential ciple for measuring differential

o an extension rod. o an extension rod.

f a metal suitable for acting as f a metal suitable for acting as

oving the extension between the oving the extension between the a transformer causes the

a transformer causes the s to vary, there by varying the s to vary, there by varying the sition of the control rod

sition of the control rod

ing a given point in a specific period of

its flow rate.”

RING METHOD

measure the flow rate of steam, water, lubricants, ai measure the flow rate of steam, water, lubricants, ai

echnology echnology creases the ability creases the ability

hich is actually a hich is actually a causes it to causes it to ce of the ce of the

ime is called

r, etc., in a r, etc., in a

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Rate of flow is measured by the diff Rate of flow is measured by the diff pipeline to create a pressure drop. pipeline to create a pressure drop. downstream. Such a reduction in pr downstream. Such a reduction in pr amount of flow must take place bef amount of flow must take place bef as the flow increases a greater pres as the flow increases a greater pres differential pressure across a restric differential pressure across a restric

ORIFACE PLATE

An Oriface plate is used to ma An Oriface plate is used to ma consist of circular plate usually inse consist of circular plate usually inse differential which is usually measur differential which is usually measur The downstream pressure is lower The downstream pressure is lower permanent loss in pressure called t permanent loss in pressure called t upstream pressure. In application w upstream pressure. In application w used.

used.

The high and low-pressure taps of t The high and low-pressure taps of t differential pressure (D/P) cell. The differential pressure (D/P) cell. The which transmits a variable 4-20 ma which transmits a variable 4-20 ma In actuality the differential press In actuality the differential press We can write this as:

We can write this as:

In other words the flow rate (Q) is p In other words the flow rate (Q) is p

To convert the signal from the flo To convert the signal from the flo one has to obtain or extract the s one has to obtain or extract the s extractor is an electronic (or pneum extractor is an electronic (or pneum transmitter and outputs a correspon transmitter and outputs a correspon

Dawood University of Engineering & Dawood University of Engineering & erential pressure method. Some form of restriction i erential pressure method. Some form of restriction i he pressure before the restriction is higher than aft he pressure before the restriction is higher than aft essure will cause an increase in the fluid velocity be essure will cause an increase in the fluid velocity be re the restriction as after it. Velocity will vary directl re the restriction as after it. Velocity will vary directl sure differential will occur across the restriction. So sure differential will occur across the restriction. So tion, one can measure the rate of flow.

tion, one can measure the rate of flow.

ke a abrupt change in the pipe area and simply ke a abrupt change in the pipe area and simply rted between pipe flanges. This produces a pressur rted between pipe flanges. This produces a pressur

d at upstream trapping and downstream trapping. d at upstream trapping and downstream trapping. han the upstream pressure; the orifice causes han the upstream pressure; the orifice causes

e head loss. This can be as high as 50% of e head loss. This can be as high as 50% of here this cannot be tolerated, a

here this cannot be tolerated, a venture tubeventure tube isis

he primary device (orifice type shown) are fed by se he primary device (orifice type shown) are fed by se output of the D/P cell acts on a pressure to milliamp output of the D/P cell acts on a pressure to milliamp signal.

signal.

re increases in proportion to the square of the f re increases in proportion to the square of the f

∆P ∆P∝∝∝∝∝∝∝∝Q2Q2

roportional; to the square root of the differential pres roportional; to the square root of the differential pres

olumetric Flow Rate = Q

olumetric Flow Rate = Q ∝∝∝∝∝∝∝∝α α ∆P∆P

w transmitter, to one that is directly proportiona w transmitter, to one that is directly proportiona quare root of the signal from the flow transmitte quare root of the signal from the flow transmitte atic) device that takes the square root of the signal f atic) device that takes the square root of the signal f

ding linear flow signal. ding linear flow signal.

echnology echnology placed in the placed in the r restriction or r restriction or cause the same cause the same

with the flow and with the flow and by measuring the by measuring the nsing lines to a nsing lines to a s transducer, s transducer, ow rate. ow rate. sure. sure. l to the flow-rate, l to the flow-rate, r.

r. The square rootThe square root rom the flow rom the flow

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P a g e P a g e | 13| 13



Flange Taps :

Flange

for orifices

A three-valve manifold ha

Orifice Plate w

VENTURI TUBE

The orifice plate produces a large h The orifice plate produces a large h of its gradually curved inlet and outl of its gradually curved inlet and outl also minimizes wear and plugging b also minimizes wear and plugging b obstruction.

obstruction.

The Venturi tube normally uses a s The Venturi tube normally uses a s where it becomes heavy and exces where it becomes heavy and exces large amounts of suspended solids, large amounts of suspended solids, orifice plate. The differential pressu orifice plate. The differential pressu pipe diameters. The Venturi tube h pipe diameters. The Venturi tube h

Dawood University of Engineering & Dawood University of Engineering &

taps are the most widely used pressure tap

to be used to protect the DP capsule from

ranged.

ith Flange Taps and Three Valve Manifol

ead loss. If this is unacceptable a venturi tube can b ead loss. If this is unacceptable a venturi tube can b et cones, almost no permanent pressure drop occur et cones, almost no permanent pressure drop occur y allowing the flow to sweep suspended solids thro y allowing the flow to sweep suspended solids thro

ecific reduction in tube size, and is not used in larg ecific reduction in tube size, and is not used in larg s

sively long. The advantages of the Venturi tube are iively long. The advantages of the Venturi tube are i it creates less turbulence and hence less insertion l it creates less turbulence and hence less insertion l e taps in the Venturi tube are located at the minimu e taps in the Venturi tube are located at the minimu s good accuracy but has a high cost.

s good accuracy but has a high cost.

echnology echnology

ping location

being

over-d

d

e used. Because e used. Because s. This design s. This design gh without gh without r diameter pipes r diameter pipes its ability to handle its ability to handle

oss than the oss than the m and maximum m and maximum

(15)

P a g e P a g e | 14| 14

PITOT TUBE

Pitot tubes also utilize the principles Pitot tubes also utilize the principles In Bernoulli’s equation, to measure In Bernoulli’s equation, to measure Most pitot tubes actually consist o Most pitot tubes actually consist o low pressure tube measures the low pressure tube measures the pipe. The second, the high press pipe. The second, the high press the pipe in such a way that the flo the pipe in such a way that the flo the tube. The pressure in the high the tube. The pressure in the high the static pressure in the syst the static pressure in the syst dependant on the force required sto dependant on the force required sto Pitot tubes are more common me Pitot tubes are more common me liquid flows. They suffer from a co liquid flows. They suffer from a co pressure differential is usually small pressure differential is usually small The differing flow velocities acros The differing flow velocities acros accuracy dependent on the flow p accuracy dependent on the flow p the position of the pitot in the pipe. the position of the pitot in the pipe.

ANNUBAR

An

An annubar annubar is similar to a pitot tubis similar to a pitot tub measures the difference between t measures the difference between t The volumetric flow is calculated fro The volumetric flow is calculated fro the pipe inside diameter,

the pipe inside diameter,

The biggest difference between an The biggest difference between an across a section of a pipe or duct. I across a section of a pipe or duct. I encountered accounting for variatio encountered accounting for variatio the tip is located at a point in the pi the tip is located at a point in the pi velocity.

velocity.

BASIC FLOW MESURING

Very simple systems employ extern Very simple systems employ extern the fluid. Others utilize floats conne the fluid. Others utilize floats conne resistance according to the amount resistance according to the amount send a signal to an instrument calib send a signal to an instrument calib The level of liquid inside a tank can The level of liquid inside a tank can liquid is constant. Differential Press liquid is constant. Differential Press the pressure at the base of a tank. the pressure at the base of a tank.

Dawood University of Engineering & Dawood University of Engineering & captured

captured flow. flow.

f two tubes. One, the f two tubes. One, the s

static pressure in thetatic pressure in the re tube is inserted in re tube is inserted in ing fluid is stopped in ing fluid is stopped in -pressure tube will be -pressure tube will be m plus a pressure m plus a pressure pping the flow.

pping the flow.

suring gas flows that suring gas flows that ple of problems. The ple of problems. The and hard to measure. and hard to measure. s the pipe make the s the pipe make the rofile of the fluid and rofile of the fluid and

used to measure the flow of gas or liquid in a pipe. used to measure the flow of gas or liquid in a pipe. e static pressure and the flowing pressure of the m e static pressure and the flowing pressure of the m m that difference using Bernoulli's principle and taki m that difference using Bernoulli's principle and taki

annubar

annubar and a pitot tube is that an annubar takesand a pitot tube is that an annubar takes this way, the annubar averages the differential pre this way, the annubar averages the differential pre ns in flow across the section. A pitot tube will give a ns in flow across the section. A pitot tube will give a e cross section where the flowing velocity is close t e cross section where the flowing velocity is close t

LEVEL

ETHOD

al sight glasses or tubes to view the height and hen al sight glasses or tubes to view the height and hen ted to variable potentiometers or rheostats that will ted to variable potentiometers or rheostats that will of motion of the float. This signal is then inputted to of motion of the float. This signal is then inputted to rated to read out the height or volume.

rated to read out the height or volume.

be determined from the pressure reading if the weig be determined from the pressure reading if the weig re (DP) capsules are the most commonly used dev re (DP) capsules are the most commonly used dev

echnology echnology The pitot tube The pitot tube dia in the pipe. dia in the pipe. ng into account ng into account ultiple samples ultiple samples ssures ssures

Glass Level Gauge

The glass level gauge or sight glass The glass level gauge or sight glass measurement as manometers are t measurement as manometers are t measurement: a very simple and ef measurement: a very simple and ef direct visual indication of process le direct visual indication of process le In its simplest form, a level gauge is In its simplest form, a level gauge is clear tube through which process li clear tube through which process li The following photograph shows a The following photograph shows a sight glass level gauge:

sight glass level gauge: 

 Bubbler Level MeasureBubbler Level Measure

If the process liquid contains suspe If the process liquid contains suspe chemically corrosive or radioactive, chemically corrosive or radioactive, prevent it from coming into direct co prevent it from coming into direct co a bubbler level measurement syste a bubbler level measurement syste shown in Figure, a bubbler tube is i shown in Figure, a bubbler tube is i the liquid level is to be measured. A the liquid level is to be measured. A through the bubbler tube. Consider through the bubbler tube. Consider escape freely at the end of the tube escape freely at the end of the tube bubbler tube (called back pressure) bubbler tube (called back pressure) the liquid level inside the tank incre the liquid level inside the tank incre of the tank (and at the opening of th of the tank (and at the opening of th pressure of the liquid in effect acts pressure of the liquid in effect acts gas from the bubbler tube. As a res gas from the bubbler tube. As a res continue to increase until it just bala continue to increase until it just bala liquid. At this point the backpressur liquid. At this point the backpressur hydrostatic pressure of the liquid an hydrostatic pressure of the liquid an Any excess supply pressure will es Any excess supply pressure will es



Ultrasonic Level Tra

Ultrasonic level instruments measu Ultrasonic level instruments measu (located at some high point) to the (located at some high point) to the further below. The time-of-light for a further below. The time-of-light for a and is interpreted by the transmitter and is interpreted by the transmitter transmitters may output a signal co transmitters may output a signal co vessel (fillage) or the amount of em vessel (fillage) or the amount of em vessel (ullage).

vessel (ullage).

     

The instrument itself consists of an The instrument itself consists of an processing circuits; plus an ultraso processing circuits; plus an ultraso is typically piezoelectric in nature, is typically piezoelectric in nature, sound waves, radio frequency and l sound waves, radio frequency and l

Dawood University of Engineering & Dawood University of Engineering & is to liquid level

is to liquid level pressure pressure

ective technology for ective technology for vel.

vel.

nothing more than a nothing more than a uid may be seen. uid may be seen. imple example of a imple example of a ent System ent System ded solids or is ded solids or is it is desirable to it is desirable to

ntact with the level transmitter. In these cases, ntact with the level transmitter. In these cases,

, which utilizes

, which utilizes a purge gas, a purge gas, can be used. can be used. AsAs mersed to the bottom of the vessel in which mersed to the bottom of the vessel in which gas (called purge gas) is allowed to pass gas (called purge gas) is allowed to pass that the tank is empty. In this case, the gas will that the tank is empty. In this case, the gas will

and therefore the gas pressure inside the and therefore the gas pressure inside the will be at atmospheric pressure. However, as will be at atmospheric pressure. However, as ses, pressure exerted by the liquid at the base ses, pressure exerted by the liquid at the base e bubbler tube) increases. The hydrostatic e bubbler tube) increases. The hydrostatic

s a seal, which restricts the escape of, purge s a seal, which restricts the escape of, purge ult, the gas pressure in the bubbler tube will ult, the gas pressure in the bubbler tube will

nces the hydrostatic pressure (P = SXH) of the nces the hydrostatic pressure (P = SXH) of the in the bubbler tube is exactly the same as the in the bubbler tube is exactly the same as the d it will remain constant until any change in the liqui d it will remain constant until any change in the liqui

ape as bubbles through the liquid. ape as bubbles through the liquid.

nsmitter

e the distance from the transmitter e the distance from the transmitter urface of a process material located urface of a process material located sound pulse indicates this distance, sound pulse indicates this distance, electronics as process level. These electronics as process level. These responding either to the fullness of the responding either to the fullness of the pty space remaining at the top of a pty space remaining at the top of a



  

electronics module containing all the power, comp electronics module containing all the power, comp ic transducer to send and receive the sound wave ic transducer to send and receive the sound wave eing the equivalent of a very high-frequency audio eing the equivalent of a very high-frequency audio aser are also used to measure level in a tank.

aser are also used to measure level in a tank.

echnology echnology d level occurs. d level occurs.

utation, and signal utation, and signal s. This transducer s. This transducer speaker. Besides speaker. Besides

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P a g e P a g e | 16 | 16



Capacitive Level Me

Capacitive level instruments measu Capacitive level instruments measu process vessel. As process level in process vessel. As process level in causing the instrument to output a causing the instrument to output a is the capacitance

is the capacitance

The amount of capacitance exhibite The amount of capacitance exhibite that vessel will vary only with chang that vessel will vary only with chang interior surface area of the vessel is interior surface area of the vessel is can affect the probe's capacitance. can affect the probe's capacitance.

Op

The simplest application is the fluid The simplest application is the fluid measurement installation using a pr measurement installation using a pr the high-pressure side of the level t the high-pressure side of the level t pressure side will be vented to atm pressure side will be vented to atm this manner, the level transmitter ac this manner, the level transmitter ac simple pressure transmitter. We ha simple pressure transmitter. We ha

 __   __        __   __ Differential pressure Differential pressure ∆   ∆        The level transmitter can be calibra The level transmitter can be calibra 4 mA when the tank is at 0% level a 4 mA when the tank is at 0% level a when the tank is at 100% level. when the tank is at 100% level.

Closed Tank Level Mea Closed Tank Level Mea

Should the tank be closed and a ga Should the tank be closed and a ga top of the liquid, the gas pressure m top of the liquid, the gas pressure m for. A change in the gas pressure w for. A change in the gas pressure w transmitter output. Moreover, the pr transmitter output. Moreover, the pr gas phase may be so high that the gas phase may be so high that the the liquid column becomes insignifi the liquid column becomes insignifi can be achieved by applying the ga can be achieved by applying the ga high and low-pressure sides of the l high and low-pressure sides of the l cover gas pressure is thus used as cover gas pressure is thus used as reference pressure on the low pres reference pressure on the low pres We have:

We have:



__   __

surement

re electrical capacitance of a conductive rod inserte re electrical capacitance of a conductive rod inserte reases, capacitance increases between the rod an reases, capacitance increases between the rod an reater signal. The basic principle behind capacitive reater signal. The basic principle behind capacitive

  

 

d between a metal rod inserted into the vessel and d between a metal rod inserted into the vessel and es in permittivity (ε), area (A), or distance (d). Since es in permittivity (ε), area (A), or distance (d). Since fixed, as is the area of the rod once installed), only fixed, as is the area of the rod once installed), only

en Tank Level Measurement

level in an open tank. Figure shows a typical open t level in an open tank. Figure shows a typical open t essure capsule level transmitter. If the tank is open essure capsule level transmitter. If the tank is open ansmitter will be connected to the base of the tank ansmitter will be connected to the base of the tank sphere. In sphere. In ts as a ts as a e: e:   ed to output ed to output nd 20 mA nd 20 mA s surement urement s or vapors exists on s or vapors exists on ust be compensated ust be compensated ill cause a change in ill cause a change in essure exerted by the essure exerted by the ydrostatic pressure of ydrostatic pressure of ant. Compensation ant. Compensation s pressure to both the s pressure to both the evel transmitter. This evel transmitter. This a back pressure or a back pressure or

ure side of the DP cell. ure side of the DP cell.

        echnology echnology vertically into a vertically into a the vessel walls, the vessel walls, level instruments level instruments

he metal walls of he metal walls of A is constant (the A is constant (the changes in ε or d changes in ε or d ank level ank level to atmosphere, to atmosphere,

hile the hile the

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low-P a g e P a g e | 17 | 17

Differential Pressure Differential Pressure

The effect of the gas pressure is ca The effect of the gas pressure is ca is sensed. When the low-pressure i is sensed. When the low-pressure i level, it is called a dry leg.

level, it is called a dry leg.

A full dry leg installation with A full dry leg installation with three-condensate will form in the low pres condensate will form in the low pres pressure on the low-pressure side pressure on the low-pressure side knockout pot/condensing bottle bel knockout pot/condensing bottle bel condensate in the knockout pot will condensate in the knockout pot will

In a wet leg system, the low-pressu In a wet leg system, the low-pressu as the process) and hence the nam as the process) and hence the nam manifold, is used in an identical ma manifold, is used in an identical ma is a small catch tank. The gas phas is a small catch tank. The gas phas tank, with the inclined interconnecti tank, with the inclined interconnecti side of the level transmitter. This pr side of the level transmitter. This pr calibration.

calibration.

∆  

∆  __ __      

ncelled and only the pressure due to the hydrostatic ncelled and only the pressure due to the hydrostatic pulse line is connected directly to the gas phase a pulse line is connected directly to the gas phase a

Dry Leg System

alve manifold is shown in Figure. If the gas phase i alve manifold is shown in Figure. If the gas phase i sure impulse line resulting in a column of liquid, whi sure impulse line resulting in a column of liquid, whi f the transmitter. A technique to solve this problem i f the transmitter. A technique to solve this problem i w the transmitter in the low pressure side. Periodic w the transmitter in the low pressure side. Periodic ensure that the impulse line is free of liquid.

ensure that the impulse line is free of liquid.

Wet Leg System

re impulse line is completely filled with liquid (usuall re impulse line is completely filled with liquid (usuall e wet leg. A level transmitter, with the associated th e wet leg. A level transmitter, with the associated th ner to the dry leg system. At the top of the low pres ner to the dry leg system. At the top of the low pres e or vapors will condense in the wet leg and the cat e or vapors will condense in the wet leg and the cat g line, maintains a constant hydrostatic pressure o g line, maintains a constant hydrostatic pressure o ssure, being a constant, can easily be compensate ssure, being a constant, can easily be compensate

echnology echnology head of the liquid head of the liquid

ove the liquid ove the liquid

condensable, condensable, ch exerts extra ch exerts extra s to add a s to add a draining of the draining of the

the same liquid the same liquid ee-valve

ee-valve

sure impulse line sure impulse line h tank. The catch h tank. The catch the low-pressure the low-pressure d for by

(19)

P a g e P a g e | 18 | 18

Measurement & control of temperat Measurement & control of temperat PRINCIPLES OF TEMP PRINCIPLES OF TEMP There in general four types of temp There in general four types of temp temperature dependent:

temperature dependent:

•

• Expansion of substanceExpansion of substance

pressure. In this simplest pressure. In this simplest

•

• Changes in electrical resiChanges in electrical resi •

• Change in contact potentChange in contact potent •

• Change in radiated energChange in radiated energ

TEMPERATURE

ure are possibly the most common operation in proc ure are possibly the most common operation in proc

RAURE MEASUREMENT RAURE MEASUREMENT

rature sensor based on following physical propertie rature sensor based on following physical propertie

ith temperature, which produces change to len ith temperature, which produces change to len for this is the common in glass thermometer. for this is the common in glass thermometer. stance with temperature, used in thermostats an stance with temperature, used in thermostats an ial between dissimilar metals with temperature, t ial between dissimilar metals with temperature, t with temperature optical & radiation pyromete with temperature optical & radiation pyromete

echnology echnology ess control. ess control. s, which are s, which are th, volume & th, volume & d RTD’s. d RTD’s. hermocouples. hermocouples. s. s.

(20)

P a g e P a g e | 19| 19



 REISTANCE TEMPERATUREISTANCE TEMPERATU

resistance is directly propor resistance is directly propor temperatures. This constan temperatures. This constan The RTD can actually be re The RTD can actually be re varies with temperature varies with temperature. Th. Th at 0 Celsius and are often at 0 Celsius and are often a)RTD using Wheatstone Bridge a)RTD using Wheatstone Bridge To detect the small variations of To detect the small variations of resistance of the RTD, a temperatu resistance of the RTD, a temperatu transmitter in the form of a Wheatst transmitter in the form of a Wheatst bridge is generally used. The circuit bridge is generally used. The circuit compares the RTD value with three compares the RTD value with three known and highly accurate resistor known and highly accurate resistor this circuit, when the current flow in this circuit, when the current flow in meter is zero (the voltage at point A meter is zero (the voltage at point A equals the voltage at point B) the br equals the voltage at point B) the br is said to be in null balance. This w is said to be in null balance. This w be the zero or set point on the RTD be the zero or set point on the RTD temperature output. As the RTD temperature output. As the RTD temperature increases, the voltage temperature increases, the voltage by the voltmeter increases. If a volt by the voltmeter increases. If a volt proportional to the temperature ran proportional to the temperature ran b) Three Wire RTD

b) Three Wire RTD

A problem arises when the RTD is A problem arises when the RTD is installed some distance away from installed some distance away from the transmitter. Since the

the transmitter. Since the connecting wires are long, connecting wires are long,

resistance of the wires changes as resistance of the wires changes as ambient temperature fluctuates. ambient temperature fluctuates. The variations in wire resistance The variations in wire resistance would introduce an error in the would introduce an error in the transmitter. To eliminate this transmitter. To eliminate this

problem, a three-wire RTD is used. problem, a three-wire RTD is used. The connecting wires (w1, w2, w3) The connecting wires (w1, w2, w3) are made the same length and are made the same length and therefore the same resistance. The therefore the same resistance. The power supply is connected to one e power supply is connected to one e that the resistance of the right leg o that the resistance of the right leg o leg of the bridge is R3 + RW3 + RT leg of the bridge is R3 + RW3 + RT cancel and therefore the effect of th cancel and therefore the effect of th Failure Modes:

Failure Modes:

• An open circuit in the RTD or i • An open circuit in the RTD or i temperature reading.

temperature reading.

• Loss of power or a short within • Loss of power or a short within



 THERMOCOUPLETHERMOCOUPLE WORKING PRINCIPLE:

WORKING PRINCIPLE:

Dawood University of Engineering & Dawood University of Engineering & RE DETECTERS (RTD):

RE DETECTERS (RTD): For most metals the chanFor most metals the chan tional to its change in temperature and is linear ove tional to its change in temperature and is linear ove tt factor called the temperature coefficient of electricfactor called the temperature coefficient of electric garded as a high precision wire wound resistor who garded as a high precision wire wound resistor who e Platinum RTD’s are constructed with a resista e Platinum RTD’s are constructed with a resista

reoffered to as PT-100 sensors. reoffered to as PT-100 sensors. e e one one . In . In the the idge idge uld uld read read

ge transducer replaces the voltmeter, a 4-20 mAm ge transducer replaces the voltmeter, a 4-20 mAm e being monitored, can be generated.

e being monitored, can be generated.

nd of the RTD and the top of the Wheatstone bridge nd of the RTD and the top of the Wheatstone bridge the Wheatstone bridge is R1 + R2 + RW2. The resi the Wheatstone bridge is R1 + R2 + RW2. The resi . Since RW1 = RW2, the result is that the resistan . Since RW1 = RW2, the result is that the resistan e connecting wires is eliminated.

e connecting wires is eliminated.

the wiring between the RTD and the bridge will ca the wiring between the RTD and the bridge will ca he RTD will cause a low temperature reading. he RTD will cause a low temperature reading.

echnology echnology ge in electrical ge in electrical a range of a range of l resistance. l resistance. se resistance se resistance ce of 100 ohm ce of 100 ohm s signal, which is s signal, which is . It can be seen . It can be seen istance of the left istance of the left

es of the wires es of the wires

se a high se a high