Data Aquisition and Monitoring System

Remote Industrial Data Acquisition, Managing &Control System This project is to be submitted to the Department of Engineering, COMSATS, Lahore for the partial fulfillment of the requirement for the Bachelor’s degree in Computer Engineering.

Internal Examiner External Examiner Name:……………… Name:……………….. Signature:………...... Signature:……………

Department of Electrical Engineering COMSATS, Lahore

Our work is dedicated to our families and teachers who have helped and

Encouraged us in every moment of our lives and made us able to achieve this place.

ACKNOWLEDGEMENTS All praises to ALLAH, the cherisher and the sustainer of the entire world, the most gracious, the most merciful, who bestowed us with health and abilities to complete this project in a success full manner. We acknowledge all the teachers, friends and specially our parents who helped us not only completing this project but also in other curriculums of our degree completion. Once again thanks to all.

ABSTRACT Phase-I of the project involves the acquisition of data from different sensors and logs this into a personal computer having data base in visual basics where the data is displayed for monitoring. Also set value defined which compares the actual data with the set values and generates commands to control the controlling elements (in our case relays) accordingly. So by the automatic control is achieved. The invention of the remote control facilities the people in ordered to control their electrical and electronics devices without manually operating them. Besides controlling the equipment at the place of installation we have uploaded this on the internet to monitor and control the equipment anywhere in the world. Phase-II of the project involves the controlling and monitoring of different electronic devices using GSM.

How It Works The whole project will be consisting of two Phases

Phase-I

It will be consisting of Sensor-Based Data Acquisition, Monitoring & Control System.

Phase-II Design and Implementation of GSM-Based Monitoring & Control System.

The Phase-1 consists of six main parts

1. Sensors 2. A\D (ADC0809) 3. Microconntroller (AT89C51) 4. Max 232 5. ULN2803 6. Software In Phase-1 Temperature sensor is used which is an analog transducer it produces a voltage according to the temperature. it produces 10mV/1C,it can measure temperature from(-50C to 150)voltage generated by the LM35 is analog this voltage is given to the analog to digital converter, the A\D converter converts this analog voltage to 8 bit binary number by Sampling, Quantization and Coding. The A\D converter is a 28 pin IC. It can take 8 analog inputs, one at a time, and can generate 8 bit binary number according to it. There are three pins 23(ADDR2), 24(ADDR1), 25(ADDR0), which are used to multiplex the inputs to the A\D converter. The program in the microcontroller sends the different combination to the address pins of the A\D converter to select the input to the A\D converter. when input is entered the A\D converter, the six no.(start)pin of the A\D converter is made high by the controller, to start conversion from analog to digital. During conversion process microcontroller monitors the EOC (End of Conversion) pin which is #9 of the A\d converter. When it becomes high mean the analog to digital conversion is completed. After it microcontroller sends high to OE (Out put Enable) pin of the A\D converter. This pin is used to get out the digital information from the A\D converter this digital output is given to the port#2 of the microcontroller. The microcontroller gets this digital number and converts into corresponding temperature. This temperature value is then sends to the PC through serial port using Max232. Max232 IC is used to make compatibility between TTL and RS232standard.TTL means transistor to transistor logic it is used in the IC mean ICs required +5v or -5v to operate.RS232standard used in serial port of the PC. It uses high value for logic0 and 1.it uses -3 to -25 for logic 1 and 3 to 25 for logic 0.Max232 has two sides one is TTL and other isRS232.TTL side is connected to ICs and RS232 side is connected to PC serial port. By this compatibility between to standard is made. There is software in the PC which is made by using Visual Basic. All the temperature readings from different sensors are logged into the software automatically. The software receives all the values from sensors after every second. The software shows the current temperature and previous temperatures of all the sensors. There is also a set point. Upper limit and lower limit options in the software. We can set the temperature in the software in the set point option for all the sensors invidually.when the actual temperature coming from the sensors is greater than the set point then the software itself generated a command and send it to the microcontroller through Max323.the relays are attached to the pot#1 of the microcontroller. according to the signal from the PC microcontroller generated logic high to its pin of port#1.at port #1

of the microcontroller a relay driving IC ULN2803 is connected, this IC is used to drive the relays. This has Darlington pairs in it. It provides ground path to energize the coil of relay. And which we want to control is attached to the relays. Relay has three contacts, common, normaly open, normally close. when p1.0 is made high by the signal from PC then pin#1 of the ULN2803 is also high by this relay attached to pin#28 of ULN2803 is energized because current flows through its coil, and its contacts changes from normally closes and load attached to it become on or off according to its connections with relay.

Block Diagram of Phase-1 Data logged is PC software can be accessed remotely by running the client program on any PC in the world which is connected to the internet. Client software has also the similar front panel view as host. We can also see all parameters on he remote PC and can also change set point.

Introduction SCADA is an acronym that stands for supervisory Control and Data Acquisition. SCADA refers to a system that collects data from various sensors at a factory, plant or in the other remote locations and then send this data to a central computer which then manages and controls the data. Supervisory Control and Data Acquisition (SCADA) is a system that allows an operator at a master facility to monitor and control processes that are distributed among various remote sites. A properly designed SCADA system saves time and money by eliminating the need for service personnel to visit each site for inspection, data collection\logging or make adjustments, Real-time monitoring, system modifications,troubleshooting,increased equipment life, automatic report generating . . .these are just a few of the benefits that come with today’s SCADA system. Other benefits SCADA systems provide:

• Reduce operational costs • Provides immediate knowledge of system performance • Improves system efficiency and performance • Increases equipment life • Reduces costly repairs • Reduces number of man=hours(labor costs) required for troubleshooting or

service • Frees up personnel for other important tasks • Facilitates compliance with regulatory agencies through automated report

generating • And more. . . . .

History of SCADA System The development of SCDA can be traced back to the early 1900’s with the advent of telemetry. Telemetry involves the transmission and collection of data obtained by sensing real time conditions, the monitoring of remote condition became possible with the convergence of electricity, telegraph, telephone, and wireless communication technology. Throughout the last century, more industries, such as gas, electric, and water utilities, used telemetry systems to monitor processes at remote sites. SCADA began early sixties as an electronic system operating as input\output (I\O) signal transmissions between a master station and Remote Terminal Unit (RTU) station. The master station would receive the I\O transmission from the RTU through a telemetry network and then store the data on mainframe computers.

In the early seventies, DCS (Distributed Control System) were developed. the ISAS5.1 standards defines a distributed control system as a system that while being functionally integrated consists of subsystems, which may be physically separate and remotely located from one another. Large manufactures and process facility utilize DCS primarily because they required large amount of analog control. Good SCADA systems today not only control processes but are also used for measuring,forecasting,billing,analyzing and planning, today’s SCADA system must meet a whole new level of control automation, interfacing with yesterday’s obsolete equipment yet flexible enough to adapt to tomorrow’s changes. Whether you need a new system or are upgrading an older one, it is important to know the system components before you decide on whom to talk with what equipment you will need for your particular applications. Components of SCADA system SCADA systems typically have four major elements: � Master Terminal Unit(MTU) � remote Terminal unit(RTU) � Communication equipment � SCADA software Master Terminal Unit (MTU) The Master Terminal Unit is usually defined as the master of heart of a SCADA system and is located at the operator’s center control facility. The MTU initiate virtually all communication with remote sites and interfaces with an operator. Data from remote field devices (pumps, valves, alarms, etc) is sent to the MTU to be processed, stored and\or sent to the other systems. For example, the MTU may send the data to the operator’s display console, store the information, and then send an operator’s initiate command to a field pump’s RTU. Remote Terminal Unit (RTU) The Remote Terminal Unit is usually defined as a communication satellite within the SCADA system and is located at the remote site. The RTU gathers data from field devices (pumps, valves, alarms, etc) in memory until the MTU initiate a send command. some RTUs are designed with microcomputers and programmable logic controllers(PLCs) that can perform function at the remote site without any direction

from the MTU.in addition,PLCs can be modular an expandable for the purpose of monitoring and controlling additional field devices. Within the RTU is the central processing unit (CPU) that receives a data stream from the protocol that the communication equipment uses. The protocols open like modbus, Transmission Control Protocol and internet protocol (TCP\IP) or a proprietary closed protocol. When the RTU sees its node address embedded in the protocol, data is interpreted and the CPU directs the specified action to take. Communication Equipment The way the SCADA system network (topology) is set up can vary with each system but there must be uninterrupted, bidirectional communication between the MTU and the RTU for a SCADA or Data Acquisition system to function properly. This can be accomplished in various waysides. private wire lines, buried cable,telephone,radios,modems,microwaves dishes,satellites,or other atmospheric means, and many times, systems employ more than one means of communicating to the remote site. this may include dial-up or dedicated voice grade telephone lines, DSL (Digital Subscriber Line).integrated services digital network(ISDN).cable, fiber optics,WiFi.or other broadband services. SCADA Soft wares A typical SCADA system provides a Human Machine Interface (HMI) allowing the operator to visualize all the function as the system operating. The operator can also use the HMI to change the set points, view critical condition alerts and warnings, and analyze, archive or present data trends. Since the advents of Windows NT, the HMI software can be installed on PC hardware as reliable representation of the real system at work. Features and Benefits of SCADA System “Automation is a need for today’s competitive market where quality, cost and availability is playing major role. Through automation only we can achieve these parameters and compete in the market”. Some of the benefits, which we can achieve with the help of industrial automation, are:

� Achieve more with less � Elimination of human error � Consistency of product � Minimize energy consumption � Easy diagnosis of fault � Reduction in resources(chemical,water,energy,etc) � Reduce manpower � Data collection and consolidation � Effective application for complex tasks � Trending and report generation � Environmental protection

� Improve safety and health � Reduce maintenance � Effect on productivity

In industry we are interested in the quality as well as the quality of the final product. So the productivity of an industry should increase.fortunately, the industrial automation results in the improved quality of product in the following aspects. � Increasing production by avoiding manual delays. � Improving productivity by achieving the optimum efficiency of the machine. � Avoiding reprocessing and improving the productivity. � Automation improves the power saving possibilities and hence the cost of product

goes down. � By avoiding manual error it improves the quality of product and hence

productivity. � Automation can give useful data of the machines which increases the possibility

of analyzing the causes of low of poor productivity.

Introduction Data acquisition system, as the name implies, are products and\or processes used to collect information to document or analyze some phenomenon. In the simplest form, a technician logging the temperature of an oven on a piece of paper is performing data acquisition. As technology has progressed, this type of process has been simplified and made more accurate, versatile, and reliable through electronic equipment.equiment ranges from simple recorder to sophisticated computer systems. The component of data acquisition system included appropriate sensors that convert any measurement parameters to an electrical signal, which is acquired by data acquisition hardware. Acquired data are displayed,analyze,and stored on a computer, either using vendor supplied software, or custom displays and control can be developed using various general purpose a programming languages such ass BASIC, C, Fortran, Java, Lisp, Pascal.specialised programming languages used for data acquisition include, EPICS used to build large scale data acquisition systems, Lab VIEW, which offers a graphical programming environment optimized for data acquisition and MAT Lab provides a programming language but also built-in graphical tools and libraries for data acquisition and analysis. Types of Data Acquisition Systems Serial Communication Data Acquisition Systems Serial communication data acquisition systems are a good choice when the measurement needs to be made at a location which is distant from the computer. There are several different communication standards, RS232 is the most common but only support transmission distances up to 50 feet, RS485 is superior to RS232 and supports transmission distances to 5,000 feet. USB Data Acquisition Systems The Universal Serial Bus (USB) is a new standard for connecting PCs to peripheral devices such as printer, monitor, modems and data acquisition devices. USB offers several advantages over conventional serial and parallel connections, including higher bandwidth (up to 12 Mbits\s) and the ability to provide power to the peripheral device. USB is ideal for data acquisition applications. Since USB connection supply power, only one cable is required to link the data acquisition device to the PC, which most likely has at least one USB port.

Data Acquisition Plug-in Boards Computer data acquisition boards plug directly into computer bus. Advantages of using boards are speed (because they are connected directly to the bus) and cost (because the overhead of the packaging and power is provided by the computer).boards offered are primarily for IBM PC and compatible computers. Feature provided by the cards can vary due to number and type of input (voltage, thermocouple, and on\off), outputs, speed and other function provided; each board installed in the computer is addressed at a unique input\output map location. The I\O map in computer provides the address locations the processor uses to gain access to the specific device required by its program. Parallel Port Data Acquisition Systems The standard port on a computer which is commonly used for a printer connection can also be used to connect to a data acquisition device. A parallel port system often supports very high sample rates. Although the distance between the computer and the data acquisition device is limited to a few feet. How data is acquired Data acquisition begins with the physical phenomenon or physical property of an object (under investigation) to be measured. This physical property or phenomenon could be the temperature or temperature change of a room, the intensity or intensity change of a light source, the pressure inside a chamber, Te force applied to an object. Or many other things, an effective data acquisition system can measure all of these different properties or phenomena. A transducer is a device that converts a physical property or phenomenon into corresponding measurable electrical signal, such as voltage, current, change in resistance or capacitor values, etc.the ability of a data acquisition system to measure different phenomenon depends on the transducers to convert the physical phenomenon into signals measurable by the data acquisition hardwre, transducers are synonymous with sensors in DAQ systems. There are specified transducers for many different applications, such as measuring temperature, pressure, or fluid flow.DAQ also deploy various signals conditioning techniques to adequately modify various different electrical signals into voltage that can be digitized using ADCs. Signal may be digital (also called logic signals sometimes) or analog depending on the transducer used. Signal conditioning may be necessary if the signal from the transducer is not suitable for the DAQ hardware to be used. The signal may be amplified or deamplified, or may require filtering, or a lock-in amplifier is included to perform demodulation. Various other examples of signal conditioning might be bridge completion, providing current or voltage excitation to the sensor.isolation, linearization, etc.

Analog signals tolerate almost no cross talk and so are converted to digital data. Before coming closer to a PC or before traveling along the long cables. For analog data to have a high signal to noise ratio, the signal to be very high. And sending+-10 Voltages along a fast signal path with a 50 Ohm termination requires powerful drivers. With a slightly mismatched or no termination at all, the voltage along the cable right rings multiple time until it is settled in the seeded precision. Digital data can have +-0.5 volts. The same is true for DACs.also digital data can be sent over glass fiber for high voltage isolation or by means of Manchester encoding or similar through RF-couplers. Which prevent net distortion.

Components of the Data Acquisition System

Sensors (temperature Measurement) Temperature is also one of the most impotent parameter in industry. There are several ways to measure the temperature including.

� Bi-materials thermometers � Resistive Thermometers � Thermocouple Thermometers � Semiconductor Junction Thermometers � Infrared Thermometers � Liquid-in-Glass Thermometers

In our project we used LM35 temperature sensors for measuring of temperature LM35 (temperature sensor) LM35 temperature sensors are precisions integrated-circuit temperature sensors, Whose out put voltage is linearly proportional to the Celsius (centigrade) temperature. The LM35 thus have an advantage over linear temperature sensors calibrated is Kelvin, as we don’t need to subtract a large constant voltage from its output to obtain convenient centigrade scaling. The Lm35 does not require nay external calibration or trimming to provide typical accuracies of +-1/4C at room temperature an+-3/4C over a full -55 to +150C temperature range. Low cost is assured by trimming and calibration make interfacing to readout or control circuitry especially easy. It can be used with single power supplies, or with plus and minus supplies, as it draws only 60*10^6A from its supply, it has very low self-heating, less than 0.1C in still air. The LM35 is rated to operate over a -55C to +150C temperature range. While the LM35C is rated for a -40 to 110C range (-10 with improved accuracy).the LM35 series is available packaged in hermetic TO-46 transistor package, the LM35d is also available in an 8-lead surface mount small outline package and a plastic To-220 package.

Features of LM35

� Calibrated directly in ° Celsius (Centigrade) � Linear + 10.0 mV/°C scale factor � 0.5°C accuracy guarantee able (at +25° C) � Rated for full -55° to +150°C range � Suitable for remote applications � Low cost due to wafer-level trimming � Operates from 4 to 30 volts � Less than 60 µA current drain � Low self-heating, 0.08°C in still air � Nonlinearity only ±1D4°C typical � Low impedance output, 0.1 W for 1 mA load

ADC0808

In our Phase-1 we have used ADC0808 A/D converter for converting the eight analog inputs coming from different sensors into 3-bits digital outputs. The ADC0808 data acquisition component is a monolithic CMOS device with an 8-bit analog-to-digital converter, 8-channel multiplexer and microprocessor compatible control logic. The 8-bitA/D converter uses successive approximation as the conversion technique. The converter features a high impedance chopper stabilized comparator, a256R voltage divider with analog switch tree and a successive approximation register. The 8-channel multiplexer can directly access any of 8-single-ended analog signals. The device eliminates the need for external zero and full-scale adjustments. Easy interfacing to microprocessors is provided by the latched and decoded multiplexer address inputs and latched TTL TRI-STATEÉ outputs.

The design of the ADC0808, ADC0809 has been optimized by incorporating the most desirable aspects of several A/D conversion techniques. The ADC0808, ADC0809 offers high speed, high accuracy, minimal temperature dependence, excellent long-term accuracy and repeatability, and consumes minimal power. These features make this device ideally suited to applications from process and machine control to consumer and automotive applications.

Features of ADC 0808

� Easy Interface to all microprocessors � Operates ratio metrically or with 5V dc or analog span adjusted

voltage reference � No zero or full scale adjust required � 8-channel multiplexer with address logic � 0V to 5V input range with single 5V power supply � Outputs meet TTL voltage level specifications � ADC0808 equivalent to MM74C949

Key Specification

Pin Number Description

1 IN3 - Analog Input 3





6 START - Start Conversion

7 EOC - End Of Conversion

8 2(-5) - Tri-State Output Bit 5

9 OUT EN - Output Enable

10 CLK - Clock

11 Vcc - Positive Supply

12 Vref + - Positive Voltage Reference Input

13 GND - Ground



16 Vref - - Voltage Reference Negative Input






22 ALE - Address Latch Enable

23 ADD C - Address Input C

24 ADD B - Address Input B

25 ADD A - Address Input A



28 IN2 - Analog Input 2 8051 Microcontroller

The Intel 8051 is an 8-bit microcontroller which means that most available operations are limited to 8 bits. There are 3 basic "sizes" of the 8051: Short, Standard, and Extended. The Short and Standard chips are often available in DIP form, but the Extended 8051 models often have a different form factor, and are not "drop-in compatable". All these things are called 8051 because they can all be programmed using 8051 assembly language, and they all share certain features (although the different models all have their own special features).

Features

� 8-bit data bus � 16-bit address bus � 32 general purpose registers each of 8 bits � 16 bit timers (usually 2, but may have more, or less). � 3 internal and 2 external interrupts. � Bit as well as byte addressable RAM area of 16 bytes. � Four 8-bit ports, (short models have two 8-bit ports). � 16-bit program counter and data pointer

Typical Applications 8051 chips are used in a wide variety of control systems, telecom applications, robotics as well as in the automotive industry. By some estimations, 8051 family chips make up over 50% of the embedded chip market.

Basic Pins

PIN 9: PIN 9 is the reset pin which is used reset the microcontroller’s internal registers and ports upon starting up.2 machine cycyle should be high at this pin.

PINS 18 & 19: The 8051 has a built-in oscillator amplifier hence we need to only connect a crystal at these pins to provide clock pulses to the circuit.

PIN 40 and 20: Pins 40 and 20 are VCC and ground respectively. The 8051 chip needs +5V 500mA to function properly, although there are lower powered versions like the Atmel 2051 which is a scaled down version of the 8051 which runs on +3V.

PINS 29, 30 & 31: As described in the features of the 8051, this chip contains a built-in flash memory. In order to program this we need to supply a voltage of +12V at pin 31. If external memory is connected then PIN 31, also called EA/VPP, should be connected to ground to indicate the presence of external memory. PIN 30 is called ALE (address latch enable), which is used when multiple memory chips are connected to the controller and only one of them needs to be selected. We will deal with this in depth in the later chapters. PIN 29 is called PSEN. This is "program select enable". In order to use the external memory it is required to provide the low voltage (0) on both PSEN and EA pins

Ports

There are 4 8-bit ports: P0, P1, P2 and P3.

PORT P1 (Pins 1 to 8): The port P1 is a general purpose input/output port which can be used for a variety of interfacing tasks. The other ports P0, P2 and P3 have dual roles or additional functions associated with them based upon the context of their usage.

PORT P3 (Pins 10 to 17): PORT P3 acts as a normal IO port, but Port P3 has additional functions such as, serial transmit and receive pins, 2 external interrupt pins, 2 external counter inputs, read and write pins for memory access.

PORT P2 (pins 21 to 28): PORT P2 can also be used as a general purpose 8 bit port when no external memory is present, but if external memory access is required then PORT P2 will act as an address bus in conjunction with PORT P0 to access external memory. PORT P2 acts as A8-A15, as can be seen from fig 1.1

PORT P0 (pins 32 to 39) PORT P0 can be used as a general purpose 8 bit port when no external memory is present, but if external memory access is required then PORT P0 acts

as a multiplexed address and data bus that can be used to access external memory in conjunction with PORT P2. P0 acts as AD0-AD7,

Oscillator Circuits The 8051 requires the existence of an external oscillator circuit. The oscillator circuit usually runs around 12MHz, although the 8051 (depending on which specific model) is capable of running at a maximum of 40MHz. Each machine cycle in the 8051 is 12 clock cycles, giving an effective cycle rate at 1MHz (for a 12 KHz clock) to 3.33MHz (for the maximum 40MHz clock). Internal Architecture

Data and Program Memory

The 8051 Microprocessor can be programmed in PL/M, 8051 Assembly, C and a number of other high-level languages. Many compilers even have support for compiling C++ for an 8051.

Program memory in the 8051 is read-only, while the data memory is considered to be read/write accessible. When stored on EEPROM or Flash, the program memory can be rewritten when the microcontroller is in the special programmer circuit.

Program Start Address

The 8051 starts executing program instructions from address 0x00 in the program

Direct Memory

The 8051 has 256 bytes of internal addressable RAM, although only the first 128 bytes are available for general use by the programmer. The first 128 bytes of RAM (from 0x00 to 0x7F) are called the Direct Memory, and can be used to store data.

Special Function Register

The Special Function Register (SFR) is the upper area of addressable memory, from address 0x80 to 0xFF. This area of memory cannot be used for data or program storage, but is instead a series of memory-mapped ports and registers. All port input and output can therefore be performed by memory mov operations on specified addresses in the SFR. Also, different status registers are mapped into the SFR, for use in checking the status of the 8051, and changing some operational parameters of the 8051.

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The 8051 has 4 selectable banks of 8 addressable 8-bit registers, R0 to R7. This means that there are essentially 32 available general purpose registers, although only 8 (one bank) can be directly accessed at a time. To access the other banks, we need to change the current bank number in the flag status register.

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The A register is located in the SFR at memory location 0xE0. The A register works in a similar fashion to the AX register of x86 processors. The A register is called the accumulator, and by default it receives the result of all arithmetic operations. The B register is used in a similar manner, except that it can receive the extended answers from the multiply and divide operations. When not being used for multiplication and Division, the B register is available as an extra general-purpose register.

MAX 232

The MAX232 is an integrated circuit that converts signals from an RS-232 serial port to signals suitable for use in TTL compatible digital logic circuits. The MAX232 is a dual driver/receiver and typically converts the RX, TX, CTS and RTS signals.

The drivers provide RS-232 voltage level outputs (approx. ± 7.5 V) from a single + 5 V supply via on-chip charge pumps and external capacitors. This makes it useful for implementing RS-232 in devices that otherwise do not need any voltages outside the 0 V to + 5 V range, as power supply design does not need to be made more complicated just for driving the RS-232 in this case.

The receivers reduce RS-232 inputs (which may be as high as ± 25 V), to standard 5 V TTL levels. These receivers have a typical threshold of 1.3 V, and a typical hysteresis of 0.5 V.

The later MAX232A is backwards compatible with the original MAX232 but may operate at higher baud rates and can use smaller external capacitors – 0.1 �F in place of the 1.0 �F capacitors used with the original device

Features

� 2.7V Operation � Dual Band, Triple Mode � Three LNA Gain Settings (Cellular) � Two LNA Gain Settings (PCS) � 18mA in Low-Gain Mode � 19.5mA in Paging and Madigan Mode � 26.5mA in High-Gain, High-Linearity Mode � 16.5mA in FM Mode, High-Gain, Low-Linearity � Mode � 2.5dB (type) Cascade Noise Figure � Adjustable LNA IIP3, +5dBm to +13dBm � Ultra-Small 28-Pin Package (5mm x 5mm)

Applications

� Portable Computers � Low-Power Modems � Interface Translation � Multi drop Rs-232 Networks

Relays

A relay is an electrically operated switch. Current flowing through the coil of the relay creates a magnetic field which attracts a lever and changes the switch contacts. The coil current can be on or off so relays have two switch positions and they are double throw (changeover) switches.

Relays allow one circuit to switch a second circuit which can be completely separate from the first. For example a low voltage battery circuit can use a relay to switch a 230V AC mains circuit. There is no electrical connection inside the relay between the two circuits; the link is magnetic and mechanical.

The coil of a relay passes a relatively large current, typically 30mA for a 12V relay, but it can be as much as 100mA for relays designed to operate from lower voltages. Most ICs (chips) cannot provide this current and a transistor is usually used to amplify the small IC current to the larger value required for the relay coil. The maximum output current for the popular 555 timer IC is 200mA so these devices can supply relay coils directly without amplification.

Relays are usually SPDT or DPDT but they can have many more sets of switch contacts, for example relays with 4 sets of changeover contacts are readily available. For further information about switch contacts and the terms used to describe them please see the page on switches.

Most relays are designed for PCB mounting but you can solder wires directly to the pins providing you take care to avoid melting the plastic case of the relay.

The supplier's catalogue should show you the relay's connections. The coil will be obvious and it may be connected either way round. Relay coils produce brief high voltage 'spikes' when they are switched off and this can destroy transistors and ICs in the circuit. To prevent damage you must connect a protection diode across the relay coil.

Advantages of relays:

� Relays can switch AC and DC, transistors can only switch DC. � Relays can switch high voltages, transistors cannot. � Relays are a better choice for switching large currents (> 5A). � Relays can switch many contacts at once.

Disadvantages of relays:

� Relays are bulkier than transistors for switching small currents. � Relays cannot switch rapidly (except reed relays), transistors can switch

many times per second. � Relays use more power due to the current flowing through their coil. � Relays require more current than many ICs can provide, so a low power

transistor may be needed to switch the current for the relay's coil

The programming languages and software used in our Phase-1 are listed below:

� C language � Keil version 3 � Proteus � Express PCB � Ms visual basic � Microsoft Excel � Microsoft Access

C Language

C is a general-purpose computer programming language developed in 1972 by Dennis Ritchie at the Bell Telephone Laboratories to implement the Unix operating system

Although C was designed for writing architecturally independent system software, it is also widely used for developing application software.

C is an imperative (procedural) systems implementation language. It was designed to be compiled using a relatively straightforward compiler, to provide low-level access to memory, to provide language constructs that map efficiently to machine instructions, and to require minimal run-time support. C was therefore useful for many applications that had formerly been coded in assembly language.

Despite its low-level capabilities, the language was designed to encourage machine-independent programming. A standards-compliant and portably written C program can be compiled for a very wide variety of computer platforms and operating systems with little or no change to its source code, while approaching highest performance. The language has become available on a very wide range of platforms, from embedded microcontrollers to supercomputers.

The code is given below:

#include <reg51.h> #include <lcd.h> void send(unsigned char value) { SBUF=value; while(TI==0);TI=0; } unsigned char receive(void) { while(RI==0);RI=0; return SBUF; } void send_string(byte *text) { do{send(*text);text++;}while(*text!='\0'); } void main() { byte *text1=" Temprature "; byte *text2="\n SET-VALUE : \n"; byte *text3=" SET-VALUE : " ; byte *text4=" Current Temprature \n" ; byte sat_value; #ifndef MONITOR51 SCON = 0x50; /* SCON: mode 1, 8-bit UART, enable rcvr */ TMOD |= 0x20; /* TMOD: timer 1, mode 2, 8-bit reload */ TH1 = -3; /* TH1: reload value for 9600 baud @ 11.0592MHz */ TR1 = 1; /* TR1: timer 1 run */ TI = 1; /* TI: set TI to send first char of UART */ #endif s1=0;s2=0;d2=0;d1=0; read_adc=25;

rw=0; lcd_ini(); send_string(text4); lcdcmd(0xC6); bcd(); send(d2+48); send(d1+48); send('C');send('\n'); while(1) { int preview; lcdcmd(0x81); lcdprint(text1); lcdcmd(0xC6); //LINE TWO POSITION preview=tlong; get_temp(); read_adc=value; bcd(); if(tlong!=preview){send(d2+48);send(d1+48);send('C');}//show temperature on Serial Port if(tlong>=sat_value)out=0; else out=1; if(sw1==0) { lcdcmd(lcd_clr); //clear lcd lcdprint(text3); //Print setting mode text on lcd send_string(text2); lcdcmd(0x0C6); //move cursor on Second line 6th column lcddata(s2+48); //print setting commands on LCD lcddata(s1+48); lcddata('C'); //lcdcmd(0x086); while(sw1==0); s2=receive();send(s2);s1=receive();send(s1); lcdcmd(0x0C6);

lcddata(s2); lcddata(s1); s2=s2-48;s1=s1-48; sat_value=s2*10; sat_value=sat_value+s1; MSDelay(150); //while(sw1==1); lcdcmd(lcd_clr); } s_delay(100); } } void get_temp() { P1 = 0xFF; //make port one as input INTR = 1; //make INTR an input R_D = 1; W_R = 0; W_R = 1; //start conversion high to low pulse while(INTR==1); //wait for end of conversion R_D = 0; //conversion finished enable rd value= P1; } void s_delay(unsigned int x) { int i; for(i=0;i<x;i++)

{ MSDelay(1); if(sw1==0)break; } }

Keil software

� When starting a new project, simply select the microcontroller you use from the Device Database and the µVision IDE sets all compiler, assembler, linker, and memory options for you.

� Numerous example programs are included to help you get started with the most popular embedded 8051 devices.

� The Keil µVision Debugger accurately simulates on-chip peripherals (I²C, CAN, UART, SPI, Interrupts, I/O Ports, A/D Converter, D/A Converter, and PWM Modules) of your 8051 device. Simulation helps you understand hardware configurations and avoids time wasted on setup problems. Additionally, with simulation, you can write and test applications before target hardware is available.

� When you are ready to begin testing your software application with target hardware, use the MON51, MON390, MONADI, or FlashMON51 Target Monitors, the ISD51 In-System Debugger, or the ULINK USB-JTAG Adapter to download and test program code on your target system.

Proteus Proteus is an easy-to-use application for creating printed circuit-board layouts, and is good for hobbyists or students working on small projects. The trial download is basically a pared-down version of Lab center Electronics' professional PCB application. Proteus creates simple PCBs with 16 copper layers, two silk screens, and four user/mechanical layers, plus an auto router. Completed designs are suitable for reports, tutorials, or articles. During testing, we found we were forced to register the program before most of the basic functions would work. Also, as the trial version has a 100-pin limitation, we only were able to test Proteus on small schema. Very user-friendly, Proteus Lite is a great program for creating PCBs--but if the trial limitations don't suit you, be sure to check out other programs that aren't as fettered.

Visual basics

Visual Basic was one of the first products to provide a graphical programming environment and a paint metaphor for developing user interfaces. Instead of worrying about syntax details, the Visual Basic programmer can add a substantial amount of code simply by dragging and dropping controls, such as buttons and dialog boxes, and then defining their appearance and behavior.

Although not a true object-oriented programming language in the strictest sense, Visual Basic nevertheless has an object-oriented philosophy. It is sometimes called an event-driven language because each object can react to different events such as a mouse click.

Since its launch in 1990, the Visual Basic approach has become the norm for programming languages. Now there are visual environments for many programming languages, including C, C++, Pascal, and Java. Visual Basic is sometimes called a Rapid Application Development (RAD) system because it enables programmers to quickly build prototype applications.

Language features

Visual Basic was designed to be easy to learn and use. The language not only allows programmers to create simple GUI applications, but can also develop complex applications. Programming in VB is a combination of visually arranging components or controls on a form, specifying attributes and actions of those components, and writing additional lines of code for more functionality. Since default attributes and actions are defined for the components, a simple program can be created without the programmer having to write many lines of code. Performance problems were experienced by earlier versions, but with faster computers and native code compilation this has become less of an issue.

Although programs can be compiled into native code executables from version 5 onwards, they still require the presence of runtime libraries of approximately 1 MB in size. This runtime is included by default in Windows 2000 and later, but for earlier versions of Windows like 95/98/NT it must be distributed together with the executable.

Forms are created using drag-and-drop techniques. A tool is used to place controls (e.g., text boxes, buttons, etc.) on the form (window). Controls have attributes and event handlers associated with them. Default values are provided when the control is created, but may be changed by the programmer. Many attribute values can be modified during run time based on user actions or changes in the environment, providing a dynamic application. For example, code can be inserted into the form resize event handler to reposition a control so that it remains centered on the form, expands to fill up the form, etc. By inserting code into the event handler for a key press in a text box, the program can

automatically translate the case of the text being entered, or even prevent certain characters from being inserted.

Visual Basic can create executables (EXE files), ActiveX controls, or DLL files, but is primarily used to develop Windows applications and to interface database systems. Dialog boxes with less functionality can be used to provide pop-up capabilities. Controls provide the basic functionality of the application, while programmers can insert additional logic within the appropriate event handlers. For example, a drop-down combination box will automatically display its list and allow the user to select any element. An event handler is called when an item is selected, which can then execute additional code created by the programmer to perform some action based on which element was selected, such as populating a related list.

Alternatively, a Visual Basic component can have no user interface, and instead provide ActiveX objects to other programs via Component Object Model (COM). This allows for server-side processing or an add-in module.

The language is garbage collected using reference counting, has a large library of utility objects, and has basic object oriented support. Since the more common components are included in the default project template, the programmer seldom needs to specify additional libraries. Unlike many other programming languages, Visual Basic is generally not case sensitive, although it will transform keywords into a standard case configuration and force the case of variable names to conform to the case of the entry within the symbol table entry. String comparisons are case sensitive by default, but can be made case insensitive if so desired.

The Visual Basic compiler is shared with other Visual Studio languages (C, C++), but restrictions in the IDE do not allow the creation of some targets (Windows model DLL's) and threading models.

Characteristics present in Visual Basic

� Visual Basic has the following traits which differ from C-derived languages: � Multiple assignment available in C language is not possible. A = B = C does

not imply that the values of A, B and C are equalled. The boolean result of "Is B = C?" is stored in A. The result stored in A could therefore be false(0) or true(-1)

� Boolean constant True has numeric value −1.[3] This is because the Boolean data type is stored as a 16-bit signed integer. In this construct −1 evaluates to 16 binary 1s (the Boolean value True), and 0 as 16 0s (the Boolean value False). This is apparent when performing a Not operation on a 16 bit signed integer value 0 which will return the integer value −1, in other words True =

Not False. This inherent functionality becomes especially useful when performing logical operations on the individual bits of an integer such as And, Or, Xor and Not.[4] This definition of True is also consistent with BASIC since the early 1970s Microsoft BASIC implementation and is also related to the characteristics of CPU instructions at the time.

� Logical and bitwise operators are unified. This is unlike some C-derived languages (such as Perl), which have separate logical and bitwise operators. This again is a traditional feature of BASIC.

� Variable array base. Arrays are declared by specifying the upper and lower bounds in a way similar to Pascal and Fortran. It is also possible to use the Option Base statement to set the default lower bound. Use of the Option Base statement can lead to confusion when reading Visual Basic code and is best avoided by always explicitly specifying the lower bound of the array. This lower bound is not limited to 0 or 1, because it can also be set by declaration. In this way, both the lower and upper bounds are programmable. In more subscript-limited languages, the lower bound of the array is not variable. This uncommon trait does exist in Visual Basic .NET but not in VBScript.

� Relatively strong integration with the Windows operating system and the Component Object Model.

� Banker's rounding as the default behavior when converting real numbers to integers with the Round function.

� Integers are automatically promoted to reals in expressions involving the normal division operator (/) so that division of an odd integer by an even integer produces the intuitively correct result. There is a specific integer divide operator (\) which does truncate.

By default, if a variable has not been declared or if no type declaration character is specified, the variable is of type Variant. However this can be changed with Deftype statements such as DefInt, DefBool, DefVar, DefObj, DefStr. There are 12 Deftype statements in total offered by Visual Basic 6.0. The default type may be overridden for a specific declaration by using a special suffix character on the variable name (# for Double, ! for Single, & for Long, % for Integer, $ for String, and @ for Currency) or using the key phrase As (type). VB can also be set in a mode that only explicitly declared variables can be used with the command Option Explicit.

Performance and other issues

Earlier counterparts of Visual Basic (prior to version 5) compiled the code to P-Code or Pseudo code only. Visual Basic 5 and 6 are able to compile the code to either native or P-Code as the programmer chooses. The P-Code is interpreted by the language runtime, also known as virtual machine, implemented for benefits such as portability and small

code. However, it usually slows down the execution by adding an additional layer of interpretation of code by the runtime although small amounts of code and algorithms can be constructed to run faster than the compiled native code. Visual Basic applications require Microsoft Visual Basic runtime MSVBVMxx.DLL, where xx is the relevant version number, either 50 or 60. MSVBVM60.dll comes as standard with Windows in all editions after Windows 98 while MSVBVM50.dll comes with all editions after Windows 95. A Windows 95 machine would however require inclusion with the installer of whichever dll was needed by the program.

Microsoft Excel

Microsoft Excel (full name Microsoft Office Excel) is a spreadsheet-application written and distributed by Microsoft for Microsoft Windows and Mac OS X. It features calculation, graphing tools, pivot tables and a macro programming language called VBA (Visual Basic for Applications). It has been the most widely used spreadsheet application available for these platforms since version 5 in 1993.

Features

Excel offers users the useful ability to write code using the programming language Visual Basic for Applications (VBA). Programmers write this code using an editor viewed separately from the spreadsheet. Manipulation of the spreadsheet entries is controlled using objects. With this code any function or subroutine that can be set up in a Basic- or Fortran-like language can be run using input taken from the spreadsheet proper, and the results of the code are instantaneously written to the spreadsheet or displayed on charts (graphs). The spreadsheet becomes an interface or window to the code, enabling easy interaction with the code and what it calculates.

The most common and easiest way to generate VBA code is by use of the macro recorder function that writes the code for the actions that the user carries out with mouse/keyboard. There is a relative/absolute toggle button that allows the user to switch between the two whilst recording a macro. Relative/absolute in this context means the relative to the start cell location or an absolute cell reference for example cell A1 (column A, row 1).Certain features such as loop functions and screen prompts by their own properties cannot be recorded, but must be entered into the VBA module directly by the programmer.

The macros can easily be activated using a button using the form menu, and advanced users can use user prompts to create an interactive program.Although conceptually simple to understand (especially using a macro recorder), the combination of multiple steps under many different constraints/conditions requires a robust testing/quality control processes to gain regular/reliable/predictable results for the product to realise its benefits.

Microsoft Access Database

� Microsoft Access database is available with the Microsoft Office Professional suite of business products therefore no additional database software is required if your company purchases computers with this suite of products already installed.

� Microsoft Access database is likely to be available and supported for years to come because Microsoft is the premier software company in the world.

� MS Access is the most widely used desktop database system in the world. � If database support is important to you then Access may be your best choice

since Access has more support and development consultants than any other desktop database system.

� It is significantly cheaper to implement and maintain compared to larger database systems such as Oracle or SQL Server.

� Company consulting rates are typically lower for Access database consultants compared to Oracle or SQL Server consultants.

� Fairly complex databases can be setup and running in 1/2 the time and cost of other large database systems (the simpler the database the greater the cost advantage).

� Access integrates well with the other members of the Microsoft Office suite of products (Excel, Word, Outlook, etc.).

� Other software manufacturers are more likely to provide interfaces to MS Access than any other desktop database system.

� When designed correctly, Access databases can be ported (usually with some difficulty) to SQL Server or Oracle. This is important if you want to start small or develop a pilot database system and then migrate to the larger database management systems.

� An Access database can be placed on a website for access for remote users. Simple screens can be developed within Access, Data Access Pages. Or full control and functionality can be implemented using Active Server Page (ASP) programming. Note that you still have the same simultaneous connection limitations described above.

Features

Microsoft Access is known for its ability to empower non-professional developers to create database applications on their own. Users can easily create tables, queries, forms and reports, and connect them together with macros. Advanced users can use VBA to write rich solutions with advanced data manipulation and user control.

The original concept of Access was for end users to be able to “access” data from any source. Access offers the ability to import and export data to many formats including Excel, Outlook, ASCII, dBase, Paradox, FoxPro, SQL Server, Oracle, ODBC, etc. It also has the ability to link to data in its existing location and use it for viewing, querying,

editing, and reporting. This allows the existing data to change and the Access platform to always use the latest data. It can even perform heterogeneous joins between data sets stored a

cross different platforms. Access is often used by people downloading data from enterprise level databases for manipulation, analysis, and reporting locally.

A significant strength of Microsoft Access is its Jet Database format (MDB or ACCDB in Access 2007) which can contain the application and data in one file. This makes it very convenient to distribute the entire application to another user, who can run it in disconnected environments.

One of the benefits of Access from a programmer's perspective is its relative compatibility with SQL (structured query language) — queries can be viewed graphically or edited as SQL statements, and SQL statements can be used directly in Macros and VBA Modules to manipulate Access tables. Users can mix and use both VBA and "Macros" for programming forms and logic and offers object-oriented possibilities. VBA can also be included in queries.

The Phase-II consists of four main parts

� GSM Mobile � Interface between device panel and GSM Mobile � Base Station � Software

Block diagram of phase-II

GSM Mobile

PC

Interface

GSM Mobile

Panel Tube

Well

GSM Mobile We have used SONY ERICSSON T290 for this purpose mainly because of two reasons

• It operates in text mode • It communicates serially with the PC • It is also cheap in market

This mobile operates in both 900/1800 GSM band Sony Ericsson T290 Data sheet GENERAL 2G Network GSM 900 / 1800 - T290i

GSM 850 / 1900 - T290a Announced 2004, 4Q

Status Available

SIZE Dimensions 101 x 44 x 19 mm Weight 73 g

DISPLAY Type STN, 4096 colors Size 101 x 80 pixels, 1.45 inches

- Wallpapers, themes

SOUND Alert types Vibration; Downloadable polyphonic ring tones, composer Speakerphone Yes

- Ring tones can be assigned to phonebook entries

MEMORY Phonebook 250 entries x 5 fields, Picture call Call records 10 dialed, 20 received and missed calls

Internal 400 KB Card slot No

DATA GPRS Class 8 (4+1 slots), 32 - 40 kbps HSCSD No EDGE No

3G No WLAN No

Bluetooth No Infrared

port No

USB Yes

CAMERA No

FEATURES Messaging SMS, EMS, MMS, Email Browser WAP 1.2.1

Radio No Games 2 - Deep Abyss and Five Stones + Downloadable Colors GPS No Java No

- T9 - Organizer

- Voice control - Voice memo

BATTERY Standard battery, Li-Ion 700 mAh (BST-30) Stand-by Up to 300 h Talk time Up to 12 h

Interface between Panel and GSM Mobile We have developed a interface which will convert electrical signal into GSM based signal and vice versa. The interface receives electrical signal and status information and converts it to the GSM signal. We have designed a circuit which will act as a bridge between the device panel and the mobile phone. The idea behind this circuit is very simple

We have used a microcontroller ATMEL (89C51) which will serve as a heart of the circuit, a MAX232 IC is used to translate TTL into RS232 standard because our mobile phone is connected serially with our circuit. A ULN 2803 IC is used to provide interface between the controller and the relays, thus in this way we have achieved our goal, our circuit is very simple, efficient and proven.

Base Station A Base station is the main room handling all the operations regarding Phase-2, it will act as a main control unit compromising of a PC and a mobile phone attached to it through a serial port. We have designed a GUI in Visual Basic which provides user friendly and simple environment for the user to handle and manage all the activities.

The best option to connect a phone to the PC is to use a standard RS232 serial cable.

Software Visual Basic was designed to be easy to learn and use. The language not only allows programmers to create simple GUI applications, but can also develop complex applications. Programming in VB is a combination of visually arranging components or controls on a form, specifying attributes and actions of those components, and writing additional lines of code for more functionality. Since default attributes and actions are defined for the components, a simple program can be created without the programmer having to write many lines of code. Performance problems were experienced by earlier versions, but with faster computers and native code compilation this has become less of an issue.

Conclusion and Future Work The current trends towards industrial automation are to develop an INTERNET and GSM based system that provides insensitivity to electromagnetic noise in industry, and communication and control capabilities within one module. This project demonstrates the versatile use of INTERNET and GSM in automation industry. It is cheaper and more efficient solution to monitoring and control. So this project is a good effort to demonstrate the use of INTERNET and GSM in automation industry. This system has created more efficient and failsafe operating conditions, enabling operators to monitor and controls and processes from remote locations in real-time. The automation introduced increases the efficiency of production process through more reliable monitoring and increased control. The technique used in this project can be modified in more refined and controllable automated solution for industrial processes, by developing some control not only on the central control console, but also on the remote terminal unit side. This will help in the more distributed control. Though the complexity of the whole system will increase but the tendency to manage a large magnitude of the process variables can be effectively enhanced

References

� Stuart A boyar ,SCADA: supervisory control and data acquisition, second edition, MC graw-hill,N.Y,1992

� P. Bhartia and R.E Collins, Modern principles of automations, third edition, MC graw-hill,N.Y,1996

� David bailey, practical SCADA for industry, wiley, N.Y,1995 � www.ni.com/labviewzone � www.verio.co.uk � www.gsm-modem.de/gsm-modem-module.html � www.bioenabletech.com/gsm � GSM And Personal Communications Handbook by Sigmund Redl,

Matthias Weber, Malcolm W. Oliphant � The GSM Network: The GPRS Evolution: One Step Towards UNTS (Paperback) � www.gsmarena.com/sony_ericsson_t290-909.php � www.atmel.com/ � www.electro-tech-online.com/micro-controllers/21879-microcontroller-89c51-

atmel.html � Microelectronic Circuit Analysis and Design by Donald Neamen (Hardcover -

Feb 21, 2006) � Computer Methods for Circuit Analysis and Design (Electrical Engineering) by

Kishore Singhal and Jiri Vlach (Hardcover - Aug 19, 1993)

� Introduction to GSM: Physical Channels, Logical Channels, Network, and Operation by Lawrence Harte (Paperback - Oct 2004)

� The GSM System for Mobile Communications by Michel Mouly and Marie-Bernadette Pautet (Hardcover - Jun 1992)

� Electronic circuit and devices theory

Schematic of Phase-I

PCB design of phase-II

Schematic of Phase - II

Data Aquisition and Monitoring System

Documents

Transcript of Data Aquisition and Monitoring System