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BOILER AUTOMATION

By

Aizaz Hussain (2005-NUST-BEE-60)

Imran Tahir (2006-NUST-BEE-115)

A Project report submitted in partial fulfillment of the requirement for the degree of Bachelors in Electrical Engineering

NUST School of Electrical Engineering & Computer Science National University of Sciences & Technology

Islamabad, Pakistan 2010

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CERTIFICATE

Certified that the contents and form of project report entitled “Boiler Automation” submitted by

Aizaz Hussain and Imran Tahir have been found satisfactory for the requirement of the degree.

Advisor: Co-Advisor:

Mr. Habeel Ahmad

(HOD EE department)

Mr. Muhammad Muzzamil

(BIS)

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DEDICATION:

We would like to dedicate this project to:

ALMIGHTY ALLAH

our parents

our teachers

our friends

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ACKNOWLEDGEMENT

We are really thankful to Almighty Allah who has blessed us with courage, effort and knowledge to complete this project .Our respected advisor Mr. Habeel Ahmad and co-advisor Mr. Muhammad Muzzamil have given us their due attention in the case of problems which we encountered during our project. Their guidelines and support was beneficiary to us. Both of them have encouraged us a lot to do the things in a new and precise way.

We are especially thankful to our friends Bilal Hussain and Faheem Manzoor who have supported us during queries and questions. Besides them our class mates were also generous towards us in the case of any help. We would like to acknowledge the efforts made by our lab administration during this project. They have issued lab apparatus on time and making lab environment friendly.

Besides all of them we are grateful to “BIS (Buraq Integrated Solutions)” for their support and help while doing this project.

At last but not least we would like to appreciate our parents for their project financial support and encouragement, which helped us to complete project on time.

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ABSTRACT:

Our designed system monitors boiler’s temperature and pressure and volume via different sensors which provide input to PLC. The output of PLC controls the boiler temperature and pressure and gives out the user required volume of steam.

All pressure and temperature variations are shown on HMI screen and are controlled through HMI. Optionally for safety measures, different automated check valves are used to release pressure and to inform the concerned authority through alarm in case of an emergency.

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Contents

1.0 INTRODUCTION ............................................................................................................................ 11

BOILER ........................................................................................................................................... 11

2.0 LITERATURE REVIEW .................................................................................................................... 12

2.1 Water‐tube Boiler:.................................................................................................................... 12

2.2 Fire‐tube Boiler: ....................................................................................................................... 13

2.3 Superheated steam boiler: ....................................................................................................... 14

2.4 Hydronic Boiler: ........................................................................................................................ 14

2.5 Fuels: ........................................................................................................................................ 15

2.6 Maintenance: ........................................................................................................................... 15

2.7 Safety Consideration: ............................................................................................................... 16

3.0 HARDWARE PART ......................................................................................................................... 17

3.1 Components ............................................................................................................................. 17

3.1.1 Water level transmitter: ........................................................................................................ 17

3.1.2 Pressure sensor: .................................................................................................................... 18

3.1.3 Temperature sensor: ............................................................................................................. 19

3.1.4 Solenoid valves: ..................................................................................................................... 20

3.1.5 Safety valve : ......................................................................................................................... 20

3.1.6 Water Pump: ......................................................................................................................... 21

3.1.7 Heaters: ................................................................................................................................. 21

3.1.8 Relays: ................................................................................................................................... 22

3.1.9 Reed Switch: .......................................................................................................................... 23

3.2.0 Programmable Logic Controller (PLC): .................................................................................... 23

3.2.1 Panel Board: .......................................................................................................................... 24

4.0 SOFTWARE PART .......................................................................................................................... 25

4.1 PC & PLC Hardware Setup and Configuration ..................................................................... 26

4.1.1MODBUS serial communication: ......................................................................................... 26

4.1.2 OPC Server: ..................................................................................................................... 27

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4.2 Programming .......................................................................................................................... 28

4.2.1The File Menu .................................................................................................................... 28

4.2.2 The Edit Menu .................................................................................................................. 28

4.2.3 The Simulation Menu ....................................................................................................... 31

5.0 Introduction to Open Control and SCADA system ......................................................................... 32

Open Control: ................................................................................................................................ 32

Benefits ...................................................................................................................................... 33

SCADA SYSTEM .............................................................................................................................. 34

5.1 Style Toolbar ............................................................................................................................ 35

5.2 Shapes Toolbar ......................................................................................................................... 36

5.3 To draw an Image ..................................................................................................................... 36

5.4 How to Apply Dynamics ............................................................................................................ 37

5.5 Hide Dynamic ........................................................................................................................... 37

5.6 Digital Color Dynamic ............................................................................................................... 39

5.7 How to apply tag ...................................................................................................................... 41

6.0 TL SOFTWARE ............................................................................................................................... 43

6.1 Code : ...................................................................................................................................... 44

6.1.1 Inputs : .............................................................................................................................. 44

6.1.2 Outputs : ........................................................................................................................... 45

6.1.3 Code Explanation: .............................................................................................................. 47

6.2 Simulation ................................................................................................................................ 64

6.3 SCADA implementation ............................................................................................................ 68

6.4 HMI screen ............................................................................................................................... 69

7.0 REFRENCES ................................................................................................................................... 71

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LIST OF FIGURES

2.1 water tube boiler…………………………………………………………………………..12

2.2 fire-tube boiler…………………………………………………………………………......13

2.3 Superheated steam boiler……………………………………………………………...…14

3.1.1.1 pcb of water level transmitter………………………………………………………....17

3.1.1.2 water level transmitter hardware…………………………………………………...…18

3.1.2 pressure guage…………………………………………………………………...……….18

3.1.3.1 3wire pt100…………………………………………………………………………..…19

3.1.3.2 temperature sensor…………………………………………………………………..…19

3.1.4 solenoid valve………………………………………………………………………….…20

3.1.5 safety valve……………………………………………………………………………….20

3.1.6 water pump………………………………………………………………………………21

3.1.7 electric heaters…………………………………………………………………………….22

3.1.8 relay………………………………………………………………………………………22

3.1.9 reed switch…………………………………………………………………………..……23

3.2.1 panel board………………………………………………………………………….……24

4.1.1 MODBUS Communication ………………………………………………………….…..26

4.1.2 OPC Server…………………………………………………………………………….….27

4.2.2.1 I/O Labels………………………………………………………………………………29

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4.2.2.2 Cust Func Table……………………………………………………………………….30

4.2.3 programmable logic simulator……………………………………………………..........31

5.0.1 introduction to SCADA system………………………………………………………....34

5.0.2 open graph…………………………………………………………………………..……35

5.1 style toolbar…………………………………………………………………..…….........…35

5.2 shapes toolbar …………………………………………………………………..………....36

5.3 to draw an image………………………………………………………………..……..…..37

5.5 hide dynamics…………………………………………………………………………........38

5.6 digital colors………………………………………………………………………………...40

5.7 tag browser………………………………………………………………………………....41

6.1.1 input relays………………………………………………………………………...……...44

6.1.2 outputs…………………………………………………………………………………....45

6.4 HMI Screen……………………………………………………………………………..….69

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LIST OF TABLES

Table 6.1.1 Relay addresses………………………………………………………………44

Table 6.1.2 output addresses……………………………………………………………...46

Table 6.1.3 coustum function……………………………………………………………...55

Table 6.3.1 Register of addresses PLC……...…………………………………………….68

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1.0 INTRODUCTION

BOILER

A boiler is a closed vessel which is used to heat up water or other fluids and those heated

or vaporized fluids are then further used for different processes. Boilers are made up of different

materials and composition of these materials change with the passage of time due to demand in

increase in strength of these pressurized vessels. Historically highest grade of wrought iron was

used to make boilers later on steel was used which is stronger and cheaper, with welded

construction, which is quicker and requires less labor. Fireboxes of these boilers are made of

copper it was chosen because of its higher thermal conductivity and its better formability but it

has been replaced by other material such as steel because of the rise in the copper price.

Steam boilers are used to produce saturated or superheated steam which are then used in

different processes like the superheated steam is used to run the turbines which in turn produces

electricity, historically steam boilers were used in trains to run the steam engines, steam is also

used in chiller of central cooling system which helps in maintaining the chemical soft inside the

chiller or otherwise it will get harder and the chiller will not work, it is also used in re-boiling

operations and cooking and there are a lot more functions of steam boiler.

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2.0 LITERATURE REVIEW

There are many different types of boiler, they are as follow

Fire-tube Boiler

Water-tube Boiler

Haycock or Pot Boiler

Superheated steam Boiler

Hydronic Boiler

But most important of these are the water-tube , fire-tube and superheated Boiler.

2.1 Water­tube Boiler:

In water-tube boilers the rack of tubes are positioned vertically in the firebox and through

these tubes water flows which gets heated upon flowing through these tubes, these vertical

pipes are called risers and these extends from the water drum which is at the bottom of the

boiler to the steam headers which are at the top of the boilers. These typically surround the

firebox in many layers like a dense forest. As steam bubbles form, they rise to the steam

drum, where the steam exits through the steam header. Following is the layout of a simple

water-tube boiler

Fig 2.1 Water‐tube Boiler Water-tubes in furnace can be arranged in many different configurations and they are

often used to connect water drums at the bottom and water and steam drum at the top, there exist

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a mono-tube boiler pump is used to circulate water through a succession of coils, this type of

boiler has very fast production of steam but has very less storage capacity. Water tube boilers are

preferred for the high pressure application because of the high pressure steam/water is contained

in smaller diameter pipes which withstands the high pressure.

2.2 Fire­tube Boiler: Fire tube boiler consists of boiler shell which is filled with water and perforated with

tubes, there are different configuration of these tubes but horizontal configuration is the common

one .water is partially filled in the water tank and volume is left inside the tank to accommodate

the steam. Long horizontal tubes are called flues and these carry the hot combustion gases

through the water tank and heating the water. The furnace is situated at one end of a fire tube

which elongates the path of the hot gases, thus expanding the heating surface which can be

further increased by making the gases reverse direction through a second parallel tube or a

bundle of multiple tubes (two-pass or return flue boiler)

Fig 2.2 Fire‐tube Boiler

The water and steam in fire-tube boilers are contained within a large-diameter drum or

shell, and such unit are often referred to as shell type boiler. Heat from the products of

combustion is transferred to the boiler water by tubes and it goes out from the smokestack. Fire

tube boilers are approximated to 360 psig of steam pressure. In case of fire tube boiler the whole

tank is under pressure so if tank bursts it creates a major explosion and if one need to increase

the steam pressure of fire tube boiler then it is necessary to increase the thickness of shell and

material of tube sheet.

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2.3 Superheated steam boiler: Reheating a steam which has been produced in the boiler becomes superheated steam,

this super heated steam is different from the initial steam which is called as saturated steam

because it has less water vapor and condense less rapidly as compare to saturated steam. It also

helps in saving coal water consumption. Basically, superheating increases the heat content and

volume of the steam, making it more fluid and using less for a given work output.

Fig 2.3 Superheated steam boiler

In case of superheated steam boiler there is a box divided in two different spaces called as

superheater header one space is for the saturated steam while other is for the superheated steam,

the saturated steam produced is passed through the pipes situated in the super heater section

where it is superheated and its temperature rises around 370 degree Celsius. This steam might be

collected in cylinder or directly given to the process dependent on it. The temperature of steam

increases in the super heater section but its pressure remains same. Superheated steam is mostly

used to move turbine as superheating steam removes all the droplets entrained in steam which

prevents damage to the turbine blades and all the pipes associated with it.

2.4 Hydronic Boiler: There are the boilers that are generally used to generate heat in residential and industrial

purposes. They work by heating the water to preset temperature and then circulating that fluid or

steam throughout the home by radiators or through floors. The fluid is enclosed in the system

and is circulated through motorized pump. This boiler may produce steam on demand and that

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can be used to generate heat or hot water can be circulated to dissipate heat on its way . Hydronic

boiler is the power plant for the central heating system.

2.5 Fuels: There are different sources of heat for the boiler. Source of heat can be natural gas, wood

coal or oil. Nuclear fission is also used as a source of heat for steam generating. These all fuels

are used in burner that on burning burns these fuels and produce heat but in case of our project

we are not using burner, our source of heat is water tube heater that works on providing 220 volts

and these heaters are inserted inside the boiler to heat up water till the time desired pressure and

volume of steam is not achieved.

2.6 Maintenance: To keep the boiler safe, efficient and to avoid the incidents boiler should be maintained

properly there are some steps that will help maintaining the boiler.

Step 1:

Cleaning boiler will allow its inspection for the possible damage and corrosion. Cleaning

and draining will also keep the parts working correctly and reduce the chance of damage to the

mechanism.

Step 2:

Water level is one of the most important that needs a lot of care. If there is a low water

level in the boiler there will be accumulation of material on the boiler surface from inside that

decreases its efficiency, so proper water level must be maintained.

Step 3:

Test all the moving parts like valve , they should function properly because they play a

vital role in keeping the boiler safe,so all the parts should be cleaned and oiled especially the

valves they should easily turned on and shut.

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Step 4:

Keep log of the boiler like when it was last test what incident took at what time this will

help to communicate valuable information to the boiler professional and helps in maintaining the

safety.

2.7 Safety Consideration: Historically there were incidents regarding the boiler which causes a lot of serious

injuries and the property destruction due to poorly understood principles of engineering. Thin

and brittle metal shells can rupture, while poorly welded or riveted seams could open up, leading

to a violent eruption of the pressurized steam. Collapsed or dislodged boiler tubes could also

spray scalding-hot steam and smoke out of the air intake and firing chute, injuring the firemen

who loaded coal into the fire chamber. Extremely large boilers providing hundreds of

horsepower to operate factories could demolish entire buildings.

A boiler can be extremely dangerous if there is loss of feed water and if permitted to boil

dry if then water is sent to the boiler the water as it contact with the high temperature shell it will

suddenly converts into high pressure steam and continuously supplying water will increase its

pressure to the point that will lead to huge explosion and that pressure generated can not be

controlled even with the safety valve. Draining can also occur if there is a leak in steam supply

lines and the water supply rate is less then the steam production and supply

As there is a lot of destruction that can be caused by the explosion of boilers both to the

human kind and industrial resources, property so we have to minimize the danger of explosion to

the lowest point and in this project we will use different tools to minimize these to the minimum

level so for that we are going to automate the boiler by introducing different components that

will alert the concerned authorities to take necessary actions so that destruction can be controlled

and loss is minimized.

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3.0 HARDWARE PART

3.1 Components

Components that we are using in our project are as following

i. Water level transmitter

ii. Pressure sensor

iii. Temperature sensor

iv. Solenoid valves

v. Water pump

vi. Heaters

vii. Relays

viii. Reed switch

ix. PLC

3.1.1 Water level transmitter:

There are different types of water level transmitters available in market but they are very

costly so we have made ourselves a water level transmitter for our boiler. We have placed

different carbon cells on a wooden stick with 2, 2 inches gap . As an output these cells attached

to our designed PCB. So when the sensors will sense the water level after 2 inches they will send

the signal to PCB and we can see water level on circuit board through 7 segment LCDs. Also we

will get signal from this PCB to PLC . So we can get signals at 8 different levels with 2 ,2 inch

gap .

Fig 3.1.1 pcb of water level transmitter

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Fig 3.1.1.2 water level transmitter hardware

3.1.2 Pressure sensor: We are using in our project a pressure gauge which will be placed at the top of the boiler

and will continuously show us analog output signal . Its pressure range is from 0 to 10 bar. We

will enter pressure into HMI screen after seeing the presure from this guage .

Fig 3.1.2 pressure guage

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3.1.3 Temperature sensor: As we have to measure high temperature for steam so we use 3wire pt100 temperature

sensor. It has very high temperature range about -200 to 850°c. It will continuously give analog

signal to PLC.

A 3wire Pt100 is a Resistance Thermometer Detector (RTD) . It has three wires that are

connected to Platinum. At a temperature of 0°c the resistance of this platinum element is

100Ω.The resistance element of this device is a piece of pure Platinum that is used for

controlling manufacturing process. Hence this is insulated and enclosed in a protective sheath.

3 wires which are connected to the resistance element are also enclosed in this protective sheath

but for easy connection to the field wiring they are extended beyond the end of the sheath.

Fig 3.1.3.1 3wire pt100

Fig 3.1.3.2 temperature sensor

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3.1.4 Solenoid valves: There are a lot of different kinds of solenoid valves for different purposes,

depending upon the process these can be selected mean if used in pharmaceuticals they

are different in food industry there are different kind of solenoid valves used similarly

they are also used in oil industry which are also different. The common factors that make

them different are there temperature, pressure, material used in making seal and seat of

the valve, material used in making body of the valve, the orifice size and the size of the

input and output ,also there different types of i/o combination valves they are available in

2/2,2/3 ,5/3 configuration .

In this project we are using 2/2 way valves (220 volts Ac) all operated with

relays(24volts Dc) and they can withstand temperature of about 150 degree centigrade’s

and a pressure of about 8 bars.

Fig 3.1.4 solenoid valve

3.1.5 Safety valve : We have placed one safety valve at the top of the boiler so that when

the pressure reaches to its maximum value (75 psi) it will automatically open to release pressure. Boilers can cause accidental explosion without safety valve.

Fig 3.1.5 safety valve

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3.1.6 Water Pump: Water pump is used to feed water to the boiler shell it is one of the most important

component, it starts automatically whenever there is water at the threshold level and this will

keep the boiler’s water level always above the threshold level. As this keeps the boiler away

from boiling dry so it plays a part in the safety issue of boiler. It is also operated with 24 volts dc

relay and needs 220 volts to start pumping water inside the boiler. It can push up to a maximum

of 5 bar pressure.

Fig 3.1.6 water pump

3.1.7 Heaters: Power of these heaters can be varied by supplying different voltages to each heater. They

are used to provide heat so that steam can be generated from water. Each can provide maximum

of about 6000 watts of power if operated with 440 volts it can also be operated with 220 volts but

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in this case there will be low power consumption of about 2500 watts but there will be variation

in rate of steam generation it will be faster if operated with the earlier voltage as compared with

the later one. There are four heaters in boiler shell, two on each side of the boil

Fig 3.1.7 electric heaters

3.1.8 Relays: There are about 10 relays that are used in this project for switching of different

components .we are operating all the components that we are using in our project with these

relays. There are two types of relays that we are using and they differ only in current rating, they

all are operated with 24 volts that is supplied from PLC device.

As heater are heavy duty and they need more current so four of the relays have about 24 amperes

current and all others have about 5-8 amperes.

Fig 3.1.8 relay

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3.1.9 Reed Switch: Reed switch are similar to the relays but reed switch are operated with permanent magnet

instead of a wire coil. When the magnet is away from the reed switch the switch is open so no

flow of current but when permanent magnet is brought near to it then due to its force the reed

switch closes and current have the path to flow. In this project reed switch is used in the hand

hole so as to see whether the hand hole is open or close because if hand hole is open and heaters

are on then the steam will exit from this hand hole and won’t be available for useful process. The

boiler will not start generating heat until and unless this hand hole is closed and it can be seen on

HMI screen with the signal coming from this reed switch. Reed switch is attached on one plane

of the hand hole while permanent magnet is fixed on the other face as shown in the figure:

Fig 3.1.9 reed switch

3.2.0 Programmable Logic Controller (PLC): A digital computer which is used for automation of electrical and mechanical processes is

called PLC. It is used for many automation processes like amusement rides, lighting fixtures or

controlling of factory machinery. It is cost effective, reliable and its programming is easy as

compared to other controllers.

T100MD-2424 is a PLC that is available in our lab. It has 24 digital input,24 digital

outputs and 8 analog I/Os. The analog I/Os are configurable, they can only be 8 analog inputs, no

analog output or they can be treated like 6 analog inputs and 2 analog outputs. 12-24 Volts DC is

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required for its central processing unit and I/Os. If one wants to operate it with 12 volts DC then

a jumper block should be placed at two pin header marked J1-12 near to the power supply

terminal and jumper must be removed if it is operated with the voltage greater then 18 volts DC.

All the information regarding this PLC device can be seen in its manual and inst-md2424 which

explains how this PLC can be installed.

3.2.1 Panel Board: This is a box where main power is supplied from outside to all the components, it

contains all the relays for different components, microcontroller circuit for water level indicator,

PLC device is also placed in this box.

Fig 3.2.1 panel board

4.0 S

SOFTWWAREE PARTT

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4.1 PC & PLC Hardware Setup and Configuration

4.1.1MODBUS serial communication:

MODBUS is an application layer messaging protocol, positioned at level 7 of the OSI

(Open System Interconnection) model,

It provides client/server communication between devices connected on different types of

buses or networks.

It is a method used for transmitting information over serial lines between electronic

devices. The device requesting the information is called the Modbus Master and the

devices supplying information are Modbus Slaves

The SCADA is the MODBUS master and the PLC works as the slave.

MODBUS is a request/reply protocol and offers services specified by function codes.

Every type of devices (PLC, HMI, Control Panel, Driver, Motion control, I/O Device…)

can use MODBUS protocol to initiate a remote operation.

Gateways allow a communication between several types of buses or network using the

MODBUS protocol.

Fig 4.1.1 MODBUS Communication

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4.1.2 OPC Server:

OPC servers do all the communications between a PC and the PLC. OPC clients tag

named objects receives event driven updates from the server.

Fig 4.1.2 OPC Server

OPC compliant applications such as a HMI (Human Machine Interface, spreadsheet,

trending application, etc can connect to the OPC Server and use it to read and write

device data.

An OPC Server is based on a Server/Client architecture which provides communication

between HMI screen and PLC.

First of all we need to setup the port on which the communication takes place.

These port may be com1 to com4.

Then we need to setup the device name (In our case is boiler).

Then we need to setup folder name (inputs, outputs, data memory and relays folder).

In this folders we may define inputs, outputs etc. According to these inputs and outputs

we may give their addresses and status like r/w(read/write)or ro(read only).

After setting all this user may give the tags to buttons, indicators on HMI screen which

control the output and input status.

OPC sever we have used :

We are using Open control MODBUS serial OPC server

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Single PLC to One PC Running TLServer This is the simplest configuration when one PLC is connected to the PC, in this case RS232 port

of PLC will be connected to any of the RS232 serial port (COM1: to COM4:) of a PC and run

the TL Server on it, more then one PLC can also be connected to the Server but in this case

RS484 port will be used and that is complex configuration.

4.2 Programming

4.2.1The File Menu New <Ctrl+N>

To create a new ladder logic program

Save <Ctrl+S>

This command saves the whole ladder logic program,

Open (Local Drive)

Save (Local Drive)

For TL5 Application (not Applet) we can open or save a file from/to the local hard disk.

Exit

Execute this command to exit orderly from the TRiLOGI program

4.2.2 The Edit Menu

1. Undo <Ctrl+Z>

Undo the last changes made to a ladder circuit.

2. Cut Circuit - <Ctrl+X>

It lets us move a block of circuits from one part of the ladder program to another part or

into another file.

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3. Copy Circuit (Ctrl+C)

We can copy a block of circuits from the current ladder program and store them into the

clipboard for pasting into another part of this ladder program or into another ladder program file

altogether.

4. Paste Circuit <Ctrl+V>

When we execute this command, the block of ladder circuit which we "Cut" or "Copy"

into the clipboard will be pasted just before the currently selected circuit.

5. I/O Table <F2>

Open up the I/O Table for defining label names for the PLC's I/O. I/O Definition Tables

Fig 4.2.2.1 I/O Labels

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Fig 4.2.2.2Cust Func Table

This table is meant for us to define a label name for a custom function

6. View I/O Type on Ladder <F3>

Toggle between display and no display of the I/O type for ladder logic contacts on the screen

7. Edit Custom Function <F7>

Opens up the Custom Function Editor window for us to enter the TBASIC

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program

4.2.3 The Simulation Menu

Run (All I/O Reset) <Ctrl+F9>

When executed, all I/O bits (including inputs) are cleared to OFF state, all integer data

are set to 0 and all string data are set to empty string. Then the "Programmable Logic Simulator"

window will open for us to conduct the simulation test of your TRiLOGI ladder program.

Fig 4.2.3 programmable logic simulator

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5.0 Introduction to Open Control and SCADA system

Open Control:

This is a is specialized software designed for Industrial Automation to provide real-time

visualization to the Executives, Management, Operators and Maintenance Staff.

OpenControl is state-of-the-art HMI/SCADA software developed by Buraq Integrated

Solutions for Industrial Automation and real-time Control.

OpenControl Software is based on industrial standards such as OPC (OLE for Process

Control) and TCP/IP for rapid and secure connectivity to multiple PLCs and Industrial

Controllers.

OpenControl provides a central control room monitoring environment, ideally suitable

where multiple brand of hardware is deployed.

OpenControl software provides true client server architecture with choice of multiple

operating systems thus using existing hardware and protecting existing investment.

Using OpenControl Industrial Automation software, you will be able to improve product

quality, reduce downtime, increase performance and provide cost savings. Fault finding

and rapid diagnostics become easy with OpenControl Suite.

OpenControl system is suitable for all industries where the requirement of monitoring

and controlling is critical.

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Benefits

• Open control software is very flexible and can be used in any type of industry .

• This software is easy to learn and can be rapidly deployed and maintained in house by the

end users .

• System integrators prefer products that offer reusability, rapid coustimization and less

programming .

The deployment of OpenControl facilitates to achieve:

Increased Production

Improved Quality

Low Production and Operating Costs

Increased Safety and Security

Reduced Downtime

Quick Diagnostics and Maintenance

The additional business benefits of OpenControl are:

Better Return on the Investment

Improved Decision Making

Meeting International Standards

Real-time Reporting

Instant Performance Indicators

Equipment Efficiency & Downtime Analysis

Finding true cost of Production

Early Warning Alarm System

Right Information to Right People

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SCADA SYSTEM

SCADA system generally refers to an industrial control system .

This is a computer system monitoring and controlling a process.

The process can be industrial or infrastructure like manufacturing, production, power generation or water treatment

SCADA system reads the measured value (flow or level ) and send the set points to PLC .

SCADA system is use to operate the PLC according to the desired input enter by the user on HMI screen.

SCADA system operates the PLC and OPC server which is use to communicate between PLC and the SCADA system is Modbus serial server.

Fig 5.0.1 introduction to SCADA system

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Fig 5.0.2 open graph

The figure above shows the Open Graph screen with its basic components, including the

Color Palette, Main toolbar, Draw toolbar, Arrange toolbar, Font toolbar, and Dynamics

toolbar.

This section describes the features of the Open Graph screen, as shown above. It also

describes the tools used to create displays and make dynamic connections to data values.

5.1 Style Toolbar The Style Toolbar provides convenient access to commonly used style functionality.

Fig 5.1 style toolbar

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5.2 Shapes Toolbar

The Shapes toolbar, shown below, is used to draw the common shapes like Line,

Multiline, Arc, Polygon, Rectangle, Hexagon, Circle, Chord and Pie.

Fig 5.2 shapes toolbar

5.3 To draw an Image

In the Shapes Toolbox, click

2- Click on the Drawing Area, where you want to draw an Image.

3- A dialog box will open, browse for the image.

4- Select the image and then click ‘open’. The image is loaded into the Drawing

Area.

5- Now you can draw as many Images as you can. To stop drawing Image selector tool

from the Shapes toolbar.

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Fig 5.3 to draw an image

5.4 How to Apply Dynamics

This chapter explains how to apply dynamics on display objects by using tags coming

from various OPC data servers. The objects are animated and controlled by the values of those

tags or data points. We can apply multiple dynamic connections to a single object. We can create

dynamic connections with functions contained in the Dynamics menu. Types of dynamic

connections include size, location, slider, rotation, dial, flash, hide, disable, analog and digital

color, fill, pick, analog and digital selector and animator.

5.5 Hide Dynamic The Hide dynamic on the Dynamics toolbar causes objects to become hidden when the

value of the digital data point to which it is connected goes either true (logical 1) or false (logical

0) as you configure it.

To define Hide for an object:

1-Select an object from the Shapes Toolbar e.g. Circle.

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2- Select the Dynamics tab from the Properties window which is located in the

Bottom, shown below:

3-Selects the Hide Dynamic as shown below:

Fig 5.5 hide dynamics

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4- Hide is the dynamic selected.

5- Object Name is a name specified to this object.

6- Property Inspector is a property sheet containing a collection of property pages. The

Property Inspector dialog box lets you view and make changes to the object parameters.

7- Hide dynamic can also be selected from the Dynamics Toolbar.

5.6 Digital Color Dynamic

The Digital Color dynamic on the Dynamics toolbar allows the color of the object to

change based on a digital event. The color connections are prioritized in the order in which they

are created. Therefore, if two data points are true at the same time, the higher-priority color

connection takes precedence. If none of the connected data points is true, the object is displayed

in its original color.

The Color connection is used to indicate states such as alarm conditions and

temperature changes, or to notify operators of the flow in a pipe.

To create a digital color connection:

1- Select an object from the Shapes Toolbar e.g. Circle.

2-Select the Dynamics tab from the Properties window which is located in the bottom, shown

below:

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3- Selects the Digital Color as shown below:

Fig 5.6 digital colours

4- Digital Color is the dynamic selected.

5- Object Name is a name specified to this object.

6- Property Inspector is a property sheet containing a collection of property pages. The

Property Inspector dialog box lets you view and make changes to the object parameters.

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7- Digital Color dynamic can also be selected from the Dynamics Toolbar, as shown

below:

5.7 How to apply tag The Tag Browser, shown in the figure below, is a tool that helps us in configuring our

OpenGraph application. Using the Tag Browser, we can connect to the OPC servers and

databases, find the available tags needed to configure the type of display that you wish to build,

and send them to OPC clients. We can also browse for aliases and variables to help you create

your displays. The Tag Browser also displays global data tags (Expressions, Value Sets, Recipes

and Groups).

Fig 5.7 tag browser

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The Tag Browser allows us to browse conveniently for several basic types of data from a

single location accessible from most Open Graph applications, including:

1- OPC tags

2- Aliases

3- Variables

4- Network nodes

5- Databases

A tag (sometimes called a "point") is a specification that, once sent to a client, will direct

our customized software to perform a desired function.

Using an intuitive point-and-click interface, the Tag Browser enables us to add tags rom the

following:

1- OPC Server(s)

2- Configuration Alarm(s)

3-Global Script(s)

More detail of these software can be found from the help manuals of the respective

software.

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6.0 TL SOFTWARE

OVERVIEW:

In software the user enters the volume of the steam that is required while the

temperature is controlled whose range is from 0---150 degrees centigrade and also the pressure is

entered by the user through HMI screen which the user read from the pressure guage which in

turns send signal to the PLC all the variations are controlled by the PLC and on achieving the

desired results alerts the user through different ways like there are LED used on the HMI screen

which light up when ever the desired result is achieved and if the user opens any available valve

it will also be shown on the HMI screen via those LED’s also all the field devices are controlled

by the PLC. In the beginning the user have to set the value of the volume for the steam that he

needs but there are certain limitation because of the level sensor that we are using the maximum

the user can enter is 175 liters while the minimum is 70 liters because in boiler the heating rods

should always be dipped in the liquid so in our case the heater’s rod are completely immersed in

the water when there is 70 liters. There are also stop button used whose purpose is whenever user

wants to stop the operation he can do so also there is an option if user wants to empty the water

shell for inspection purpose or for some other purpose he can do so. Further explanation will be

presented in the code menu. One thing to remember in coding that HMI can only change relays

and data memory, so inputs shown on HMI screen are basically sending values to relays and data

memory. So coding involves using of relays, instead of digital inputs. In case of analog inputs,

value is stored in data memory of PLC.

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6.1 Code :

6.1.1 Inputs : These are the inputs that user have the access to set them from HMI screen. Inputs used are

all relays, because we can control inputs of PLC only through external sources. We can’t control

PLC’s inputs through industrial automation suite (Open Control SCADA system). But relays can

be controlled by SCADA system. The input relays we defined are as follows:

Fig 6.1.1 input relays

These are the relays that we have used in our project addresses for these relays which is to be

entered in the OPC server software are as follow

Table 6.1.1 Relay addresses

Serial no Relay address

1 START 1025

2 STOP_1 1026

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3 VALV_A 1027

4 VALV_B 1028

5 SP_O_VALVE 1029

Stsrt is used to give user the option to start the operation mean start the boiler whereas if user

wants to halt the system he can do so by pressing the relay named as STOP_1, VALV_A and

VALV_B is used to give the operator the choice to open either Valve A or Valve B. if operator

wants to empty the water shell he can do it by pressing from HMI screen and for that

SP_O_VALVE is used.

6.1.2 Outputs : Outputs can be addressed either by there names or by their bits. In our case we have

addressed the output by there names because this is the easy way, addressing by the bits is

difficult as user have to remember output bit number of respective output field device ,using

names of the field devices as the output addressing is the most easy and memorable way.one

thing must be remembered that output 7 and 8 are for PWM. Field devices that we have used

which are to be controlled via the PLC, there output addressing is as follow;

Fig 6.1.2 outputs

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SO_VALVE is used for the spill out vlave through which fluid can be spilled out from

the tank while PR_VALVE, VALVE_A, VALVE_B are the output valves through which the

steam is exited and two valves named A and B are used if the operator wants to use that steam in

some process he can open valve A while for the other process he can open valve B.

VALVE_MTR is the valve that is placed right after the water pump this us used to stop the back

flow of water from the tank while WATER_PUMP is used to insert water inside the main

tank.HEATER_1, HEATER_2, HETER_3, HEATER_4 are the four heaters that we have used to

heat the water inside tank to make steam out of it while the SCDA _ALARM is used to alert

operator that the desired results have been achieved where as ALARM_1 is used to alert the

same operator if for any reason the volume, temperature or pressure is increasing after achieving

the required results then it will start, but if the pressure,volume or temperature have increased to

the critical level that it can cause a very large scale damage to the people as well as to the

building then this ALARM_2 will be ON and will remain ON until and unless the parameters

decreases from the critical values. They are addressed in the OPC server software by the

following addresses;

Table 6.1.2 output addresses

Serial No Output Addresses

1 SO_VALVE 257

2 PR_VALVE 258

3 VALVE_A 259

4 VALVE_B 260

5 VALVE_MTR 261

6 WATER_PUMP 262

7 HEATER_1 265

8 HEATER_2 266

9 HEATER_3 267

10 HEATER_4 268

11 SCDA_ALARM 269

12 ALARM_1 270

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13 ALARM_2 271

6.1.3 Code Explanation:

Clock energizes custom function every one second. When this custom function is energized,

following code will run

As per our requirement the minimum steam volume is 7o liters so user have to enter

equal to or greater then this otherwise the code wont proceed so when the user enter required

steam volume it is saved in the memory location 1and the steam volume must also not exceed

175 liters otherwise there will be error. Basically data memory is used to get input data from

SCADA system. We store the value of data memory from HMI which changes the input

functions according to defined in PLC’s custom function.when the user inputs steam volume

equal to or greater then 70 liter or less then 175 liter then it will set other input function which

cause the execution of another custom function which s as follow:

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As the above custom function executes it will clear all the valves ,water pump.it will also

clear STOP_1 which will be explained later it also clearOPEN_VALV so user will have no

option to open Valve A and B in the beginning .further more when the user enter START button

from rellay then the above custom will execute

SYS_ON and START was made closed by the user previously here it will check either

the hand hole is open or closed because if the hand hole is open then there is no use of operating

the boiler because then there will be no storage of steam and it will go out from the hand hole

which is also the wastage of resources and that steam which is going out from the hand hole can

not be used for any sort of process because some process need the pressurised steam like in case

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of turbines it needs a lot of pressure to move the turbines to make electricity and also continuous

flow of steam is also required in central heating system with certain pressure that’s why it is

necessary that the hand hole remain close down if there is need of steam. This circuit will cause

the execution of another custom function namely SYS_CHKED , explanation of this custom

function is as follow:

So another circuit will short down making its way to another custom function . Above

custom function will short SYS_CHKED1. The circuit is as follow:

We have used the clock of time period 1 second so as to check after every second that

either the value of sys_chked1 is changed or not and it will make execution of another custom

function named CHK_WATER which is explained as follow;

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So the previous start button pushed by the user after setting the value of required steam is

cleared of here so that the respective custom function of the START do not execute. Here the

water level is determined and if it is less then the level detector’s 35 liters while in real it will be

very much less then 70 liters then it will call custom function which is at number 29 and named

in the custom function list as FILL_WATER is as follow:

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It will short another circuit ans make clear others. The circuit of STRT_MTR is as

follow;

And the corresponding custom function is as follow;

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While filling the water we are opening the PR_VALVE, VALVE_A, VALVE_B so that

all the air present initially inside goes out and the pressure remain constant if it was not done

then the pressure guage should show some pressure which is not due to water but due to the air

present inside the tank and the pressure guage will show presssure when water is inserted in the

tank, it is also necessary to open the VALVE_MTR because if it is not open the water will not

flow inside the tank and also there will be damage caused to water pump and this valve.

In the above custom function number 12 named CHK_WATER if the first condition

comes out to be wrong then the second will be seen and if it comes out to be true then the

following custom function number 30 named STRT will execute.

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Water level have reached to its highest level so the water pump will be switched off and

all the valves will be make close another circuit will turn on

START_OPRT custom function will execute on shortning of the above circuit. Uptill

now water has reached to its maximum height and the operation will begin so in the following

custom function heaters are turned on and the process of steam genertation will begin and the

water level will starts to fall down and this felling down level of water is used to estimate the

volume of the steam generated by making the another circuit short starting from PVT which

contains the normally closed inputs which is opposite to the water level detector which contains

the normally open inputs. As the water level increases it will make the inputs named IN_1

….IN_8 close and the corrseponding function will execute which will give out different valuesof

water level on every shortning of water level indicator’s graphite with the low voltage signal

coming from low potential of PLC and this value of increasing and decreasing water level is

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stored in the memory location DM[2] while the steam volume circuits conatian normally closed

IN_1……IN_2 so It will work oppositely to the water level indicator. Figure A shows the above

circuit corresponding custom function while Figure B shows the water level circuit.Figure C

shows the steam volume circuit;

Figure A

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Above is Figure B.

Above is the custom function of the corresponding IN_1 which is stroing a value of 35 in

memory location 2. Similarly other contains the following values;

Table 6.1.3 coustum function

Custom function name Value contain

C_70 DM[2]=70

C_105 DM[2]=105

C_140 DM[2]=140

C_175 DM[2]=175

C_210 DM[2]=210

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C_245 DM[2]=245

C_280 DM[2]=280

Figure C

Going back to the custom function number 15 named START_OPRT it aslo contain the

third condition which on becoming true will cause another circuit to short. It says that IF

memory location 2 contains a value of 280 then CALL 31 which is also a custom function and it

will make this circuit to work

The custom function of the respective above circuit contains

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The heaters were on when the water level reached 245 liter level but then it reaches 280

liters they will be made turn off and the spill out valve will open so that the extra water above

245 level is spilled out and this level is achieved.

As the water level goes down the volume will increse and the clock of 1 second time

period is used to update volume value and as the user set volume is achieved it will short another

circuit

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Custom fnction of the respective above circuit contains

Here we need to uncheck the START_1 so that it do not check the water level again

because if the user puts the maximum steam volume then it will start again filling the tank when

the volume reaches to its max but due to clearing it here that circuit switches off. The heaters are

shut down and thr pressure releif valve is open and choice has been given to the user either he

wants to open Valve A or B.

The custom function named USER _PRESS is use to take pressure vlaues from the user

which he take from the pressure guage and enter it through HMI screen and the clock is again

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used to update the values that user enter .the custom function defiend above is explained as

follow;

When the user enters the values into HMI screen it is saved in the memory location DM

[4] but there are certain limitation for the pressure that should build inside and for the safety

measures steps are taken to minimize the damage in case of emergency. Max pressure of 60 psi

is a safe pressure that can build inside but as it reaches ti 60 psi it will inform the operator by

scada alarm and again the pressure relief valve will be open and user will have a choice either to

open valve A or B, but if it does not occure for any reason and the pressure remains on

increasing then if it goes beyond 65 psi but remain less then 75 psi then it will make another

circuit short which is as follow;

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It will make the execution of another custom function named HEATER_OFF1 whose

function is defined as follow;

The scada alram was made on previously and it will remain ON untill and unless the

pressure is decreased below 60 psi but in case it goes on increasing the above custom function

will execute in which another alarm ALARM_1 hich is a physical alarm will start, all the heaters

are made clear they are shut down over here . Again the pressure relief valve is open and the user

have been given an option to open any of the two valve.similarly same is the circuit for the

temperature that increases when the heaters are ON and sesnsor is used which will be sending the

values of the increasing temperature. Its circuit is as follow;

The custom function for the above circuit is as follow;

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The values are saved in the data memory DM[3] and this inputs to the PLC device at

analog to digital convertor port number 2. We also have limitations for the temperature like if its

goees beyond 423 kelvin and remain less then 430 kelvin then it will make anochtr circuit short

which is explained earlier which is adjacent with the PRESSUE_1 and its function is also

explained abovebut if it remain goes on increasing and goes beyond 430 kelvin it will make

another circuit short by making TEMP_2 close else if the temp remain below 423 kelvin none of

the TEMP_1 and TEMP_2 will be will be made close. The custom function for TEMP_2 is as

follow;

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The two alarms SCDA_ALARM and ALARM_1 were made ON previously but as

temperature increase above 430 kelvin another physical alarm named ALARM_2 will be mae

ON whose purpose is to inform all the people inside the building and to evacuate tht building and

all the heaters area again made OFF if previolsy they failed to switch off.similar is th case fot the

pressure if its goes beyond 75 psi the manual safety valve whose value is fit at about 75 psi will

open and the pressure built inside tank will be released through this safety valve and the pressure

will decrease to its mnimun and as it goes below 75 psi the ALARM_2 will be switched off and

as it goes below 65 psi another ALARM_2 will be switched off and same if its goes beyond 60

psi all the alarms will be switched off. The circuit for the pressure_2 is as follow;

Custom function for HEATER_OFF2 is explained above.

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We have used relays for opening of the vave A and valve B whose circuit are as follow;

OPEN_VALV is made closed in the custom function whenever there is need to evacuate steam

from the boiler while VALV_A and VALV_B are the relays used which make the respective

valve open by choosing from the HMI screen.

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6.2 Simulation

This is how our simulation look like initially VOl_3 and PR_VALVE is checked because

it is programmed like this that whenever DM[1] = DM[11] check VOL_3 which will inturn open

the PR_VLAVE and check OPEN_VALV this time user have the choice to open either of the

valve by checking any of the vlave relay.

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Now the user have entered the volume of steam required so it will make check SYS_ON

indicating that the volume entered was correct volume otherwise it will remain uncheck if it is

out of range so the user have to check the START button tfor furhter execution of the code and

here it will check the water level initially the water level was at zero so the water pump will start

puming water inside the tank and when it reaches to it reaches to its final value the water pump

and the pump valve will close down whereas the heater will switch on and it aslo checks the PVT

because the heater are switched on so by heating the water will start converting into steam so the

water level will be falling down and the steam volume will increase whose values will be stored

in DM[11] which is the custom function of the corresponding PVT inputs which will switch on

the circuit as it goes close. START_1 is also checked here at this point which execute the custom

function which switch on the heaters.

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It is shown over here that user have enterd the steam of volume which is saved in the

memory location DM[1] and DM[2] shows the volume of water remaining in the tank after

achieving the deired volume of steam which is stored in memory location DM[11].

The simulation diagram below shows what will happen when the desired volume is

achieved .when the required volume is achieved the heaters will shut down VOL_3 is checked

OPEN_VALV is also checked which inturn will provide the option for the user to open any of

the available valve for evacuation of the steam.IN_1 is still on which shows the current water

level which it is showing as 35 liters but in real there will be 70 liter of water thisis because as

the graphite cell in the water level indicator makes the second level indicator of the system will

assume that the water level have reached to 35 liters which is the minimum water level but in

real minimum water level is 70 liter at which the heater rods are completely immersed in the

water keeping them away from heating dry.

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The last simulation diagram shows that when initially the water pump starts filling

water and the STOP_1 button was pressed then the water pump will close down also the pump

valve will close down and if the user wants to spill out the water he can do so by pressing down

SP_O_VALVE from HMI screen. The operator can open the spill out valve any time when the

system is off meaning that the pressure inside the boiler is zero and the heaters are switched off.

6.3 SCADA implementation

Table 6.3.1 Register addresses of PLC: Inputs 1-96

Outputs 257-352

Timers 513-576

Counters 769-832

Relay 1025-1536

Data memory 4-1001---4-5000

Timer PV value 4-0129---4-0192

Counter PV value 4-0257---4-0320

Time[1] 4-0513 Hour

Time[1] 4-0514 Minute

Time[1] 4-0515 second

Date[1] 4-0516 year

Date[1] 4-0517 Month

Date[1] 4-0518 Day

Date[1] 4-0520 Day of week(string)

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6.4 HMI screen Basically HMI screen is use to monitor the whole system. We just apply the input signal

on screen according to that input desired functionality is performed. The reason of designing the

HMI screen is to make the automatically controlled device for ease of users and their desire. We

have made our HMI screen through which input and outputs of boiler unit are controlled. We

have different input buttons according to which the different outputs are controlled.

Our HMI screen looks like this as shown below;

Fig 6.4 HMI Screen

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The user can enter the required steam volume on the left hand side under the heading of

user data’s volume, he can also put the pressure values read from the pressure guage. While the

three meter in the center below will show the Pressure built inside tank ,temperature and the

steam volume inside tank respectively. The two switches tagged start and stop is use to start and

stop the operation of the boiler ahile the switch shown with each valve can be operated so as to

open respective valves of respective switches.

On the right hand shown STATUS consist of leds of respective devices, which will

switch on when there respective device switches on, like if Heaters are on the corresponding

LED to the Heater will remain on as long as heaters are switched on. The 0.0L shown on the tank

shows the volume of water inside the tank whose value will increase or decrease depending on

the volume of water inside the tank.

The delievery pipes will change itsw colour when ever steam or water pass

through it, like pipes conneccted with water pump and the pump valve will change its solour to

sky blue whenever water flows through it which depends upon the switching of water pump,

similar is the case for the pipes attatched for the purpose of drain. The pipes for evacuation of the

steam will change its colour to red when ever there is passing of steam while to show which

valve is open and close, the pipe that are attatched on the right side of the Valve A and B will

change its colour depending upon which one is opened.

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7.0 REFRENCES

http://www.mckenziecorp.com/boiler_tip_8.htm

http://www.cip.ukcentre.com/pt100.htm

http://en.wikipedia.org/wiki/Boiler

http://www.tpub.com/content/construction/14279/css/14279_14.htm

http://www.scif.com/safety/safetymeeting/Article.asp?ArticleID=5

www.absoluteastronomy.com/topics/Fire-tube_boiler