wire less microcontroller based liquid pump

8/16/2019 Wire Less Microcontroller Based Liquid Pump

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Debre markos university(DMU) 2007

CHAPTER ONE

INTRODUCTION

1.1 Background The project ―Wireless micro controller based automatic liquid pump controlling system is

design to monitor the level of liquid in the tank or any other materials. The system basically operatedwith micro controller and RF(Radio Frequency) transceiver modules. Wireless liquid level controller isequipment used to control the liquid level in the tank. The level of the water is controlled by using aprobes used as a sensor which inserted inside a tank and microcontroller

.Key words:- sensor modules, RF transceiver, micro controller, power supply, and indicator etc.The sensors sense the presence of liquid like water and give indication to RF transmitter. Thetransmitter transferring data to RF receiver then to the micro controller. The microcontrollerproduces the control signals to drive the motor. If there is liquid in sump (reservoir) thenmicrocontroller gives control signal to start the motor and if there is insufficient liquid/water in thesump (reservoir) tank then the microcontroller gives control signal to stop the motor. And also themicrocontroller enables the indicator and indicated as “blinking the LED” when there is no liquid in the

sump tank and stop to blink when there is liquid in the sump tank. Hence the level of liquid in a sumptank can be automatically controlled. The probes in the sump used us the sensor. These two

conductors checks the availability or in availability of liquid in the sump tank. If there is liquid then theconduction occurs between the two conductors, which closes a circuit to the microcontroller and

microcontroller detects the intensity of liquid in the sump tank. If there is no conduction,microcontroller detects absence of liquid/warer in the sump tank.The PIC microcontroller obtaining signal from the receiver.The microcontroller produces controls signal to the drive the motor according to the indication and enables the indicator. The motor is controlled by a relay mechanism. Motor is controlled by the Microcontroller, the microcontroller switching the power supply to motor by relay mechanism. The system has wireless an automatic

pumping system attached to it. so as to refill the tank once the liquid gets to the lower threshold,

while offing the motor once the liquid gets to the higher threshold.This project is quietly solving for instance: poor water allocation, inefficient use of water and lack of adequate and integrated water management. Water is commonly used for agriculture, industry, and domestic consumption. Therefore, efficient use and water monitoring are potential constraint for home or office water management system. Moreover, the common method of level control for home appliance is simply to start the feed pump at a low level and allow it to run until a higher water level is reached in the water tank. This liquid level controlling also control, monitor and maintain the water level in the overhead tank and ensures the continuous flow of water round the clock without the stress of going to switch the pump ON or OFF Thereby saving time, energy, water, and prevent the

pump from overworking. Besides this,


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Debre markos university(DMU) 2007liquid level control systems are widely used for monitoring of liquid levels in reservoirs, What it needs

is for the transmitter to activate the receiver and hold it in the on position till the probes switch interrupts the transmitter and releases the receiver.Generally switch ON the pump when their taps go dry and switch OFF the pump when the tank reaching at the final thresheshold level. This results in the unnecessary wastage and sometimes non availability of water in case of emergency.

pump

setpoint

Figure 1.1 A Typical liquid level control system

1.2 Aims and objectives The goal or objectives of our project is to build Wireless micro controller based an automatic

liquid pump controlling system. In this project sensors are place at different level inside of the tank

and with the aid of this sensors, the micro-controller monitor the level of the liquid and activate or

deactivate the motor .some of the objectives are:- 1. To design Wireless microcontroller based an automatic water/liquid pump monitoring and controlling system.

2. To control the water/liquid level in the tank by interfacing a RF module with microcontroller to build a wireless remote control.

3. To solve the problem of water tank system users.

4. To reduce in appropriate loss of water caused by water tank system(To avoid wastage of water).

5. Since the demand of electricity is very high, automatic water level control saves energy .

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1.3 Statement of the Problem Today, most of the liquid/water tank users in industries have replaced conventional pump with

electrical pumps. But they find it very inconvenient for the condition of water or liquid pump because there is no effective liquid level indication system. As a result, if mechanical sensor fails, there are a

plenty of water waste as well as wastage of power consumed by motor pump. Solution of this problem is wireless liquid tank level controller using water level sensor and microcontroller .

1.4 Significance of the project Wireless automatic liquid level monitor came into existence because of human error and

inconsistence that is associated with manually operated water pumping machine. This is because it takes time for individual who is manually operating the water pump to turn off the pumping machine and this may cause water spillage and at times the individual might not know that the water level has drop so low until the tank is completely empty. This was the problem that leads to the development of the ideal of an automatic liquid level control and automatic pump short down.

1.5 Scope of the project

In this paper we are discussing about design and implementation of liquid level control system which is wireless, automatic, cost effective and reliable by using Radio frequency transmitter and receiver with a micro controller installed at the tank and sump. Radio Frequency transceivers are used for wireless communication.In our project we will be able to do simulation part. The project was design to Wireless automatically control the pump which ensures constant reserve of water in the reservoir. The scope of the design

was keep concise and simple.in other way this project mostly concerned with not to introduce unnecessary complexities and render it generally uncomfortable.


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Debre markos university DMU) 2007

CHAPTER ONE

LITERATURE REVIEW OF PROJECT Out of the liquids which are involved in this contenent is Water which is commonly used for

agriculture, industry, and domestic consumption.this feature inforce us to cncentrate on it.

Therefore, efficient use and water monitoring are potential constraint for home or office water

management system. In the last few decades several monitoring systems integrated with water level

detection have been accepted. Measuring water level is an essential task for government and

residence perspective. It would be possible to track the actual implementation of such initiatives with

integration of various controlling activities.

The level measurement consist of determining the distance from the upper surface of a liquid in a reservoir or vessel or any arbitrarily chosen mark located above or below this surface by itself the level is not an independent physical quantities describing the state of a substance through direct and indirect level, some examples of direct level measurement are dipstick, the bubbler, immersion electrode, capacitor type ,liquid level radiation type liquid level measurement for instance the dipstick,it is very simple, the stick being dipped periodically through a hole and the hole and the immersion mark is being read off with the aid of the calibration on the stick. Then, the direct level measurement are sight glass ,depending on the manometer principle, the transparent tube is place in a convenient

and its being connected to the lower part of tank and graduated for safety reasons, the top the bright glass is vented into the tank and the sight has isolation valve top and bottom while the micro base; water level controller has the ability to switch on the pumping machine when the water in the tank has gone below gauge level automatically switches theOFF the pumping machine when the water in the tank has reach its maximum level.An automatic water level control detects the water level in the tank and also ensures continuous water flow round the clock because of its automatic, this automatic water control is made up of microcontroller written in C programming language this program is burn into a PIC called 16F877A With 40 pins. In this paper we discuss about automatic water level sensing and controlling with

wireless communication between controllers placed at the tank and the sump. So the system basically operated with controllers and RF transceiver modules.

The paper introduces the notion of water level monitoring and management within the context of electrical conductivity of the water. More specifically, it explains about the microcontroller based water level sensing and communicates with in a wireless environment. Water Level management approach would help in reducing the home power consumption and as well as water overflow. Finally,they have proposed a web and cellular based monitoring service protocol that would determine and sense water level globally. It discusses about the monitoring system to monitor the changes of water


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level from time to time. The traditional irrigation area automatic system mostly uses the wire to

connect the water level, rainfall and gate position sensors and the data acquisition to transmit the hydrographic information. But in the wireless system there is no complex wiring, wire damage, and the cost in installment and maintenance is less. So it enhances the systems reliability and extension.A range of level control systems and methods are used in industry. Systems may be based on the use of floats, probes or sensor. Level control is one of continuous process that can be treated as an integrating process. The level controller can be applying on temperature control, pressure control,and water control. The level controller is used with electrical probes or sensors. The electrical probes are used with power supply and motor. The probes will put inside the tank and the motor will pump as

the water goesdown. The probes will detect the level of the water and on/off the motor.

The level controller which are using water sensor will sense the low and high level of water in water tank. If the water was low, the motor will pump the water and will stop to pump water after the high level reached.Automatic Water level Controller can be used in Hotels, Factories, Homes Apartments, Commercial Complexes, Drainage, etc. It can be fixed for single phase motor, Single Phase Submersibles, Three Phase motors. We can control two motor and two sumps and two overhead tanks by single unit.Automatic water level controller will automatically START the pump set as soon as the water level falls

below the predetermined level (usually 1/2 tank) and shall SWITCH OFF the pump set as soon as tank is

full.

Electronics circuit has undergone tremendous changes since the invention of a triode by Lee De Forest in 1907. In those days the active component likes resistors, inductors and capacitors etc. Of the circuit were separated and distinct unite connected by soldered lead with the invention of a transistor in 1984 by W.H Brattain and I.barden, the electronic circuit became considerably reduced in size. It was due to the fact that transistors were not only cheaper, more reliable and less power consumption but was much smaller in size than an electronic tube. To take advantage of small transistors size, the passive component too were reduce in size there by making the entire circuit very small development of printed circuit board(PCB) further reduce the size of electronics

equipment by eliminating bulky wiring and tie point. In the early 1960s a new field of micro-electronics was born primarily to meet the requirement of the military which was to reduce the size of it electronics equipment to approximately one tenth of it then existing volume. The drive extreme reduction in the size of electronic circuit has lead to the development of micro-electronics circuit called integrated circuit (ICS) which are so small than their actual construction is done by technicians Using high powered microscopes. An integrated circuit is a complete circuit inwhich both the active and passive component are fabricated in on a tiny single chip of silicon, Active component are those which have the ability to produce gain example are transistors and field effect transistors (FET). An integrated circuit sometimes called a chip or microchip is a semi-conductor wafer on which

thousands of millions of tiny transistors, capacitors are fabricated, An IC can be either analog digital depending on its intended application.


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Many earlier works dealt with various techniques of monitoring and controlling of liquid levels in industrial and domestic applications. Broadly this automatic control problem can be achieved under two means: mechanical methods and electrical methods. Float ball type liquid level control is a popular method of control still used in practice for normal applications such as overhead tank overflow restrictors etc. The electrical methods of control include a micro controller -based circuits which automatically predict the cndition of liquid levels and accordingly active the circuit to operate motors.In spite of several such available methods, still there are new techniques in this application so as avoid dangerous operating conditions in industrial boilers.

Tan: - proposed a water level control system for nuclear steam generator. The control system

consisted of a feedback controller and a feed forward controller. The robustness and performance of both the controllers are analyzed and tuning of the parameter of the controllers. It is shown that the proposed gain scheduled controller can achieve good performance at high and low power levels.Safarzadeh: - presented a water level control system for horizontal steam generators using the

quantitative feedback theory.

Moradi : - proposed a control strategy to achieve desired tracking of drum water level. Sliding mode &

H-∞ control schemes are employed. Transfer function between drum water level (Output) and feed

water vs. steam mass rate were considered.

Maffezoni :- highlighted the principal dynamic phenomena which determine the structuring of boiler-

turbine control systems, clarifying the essential connections of such phenomena with the physical

nature of the process. Zhang and Hu:-proposed the water level control system using PI controllers.

Zhang: - analyzed the water level control of pressurized water reactor nuclear power station using

PID and fuzzy controllers. Ansarifar :- proposed an adaptive estimator based dynamic sliding mode

control method for water level control. Liu : - presented a proportional controller with partial feed

forward compensation and decoupling control for the steam generator water level.


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CHAPTER THREEMETHODOLOGY

There are many methods of designing an automatic water level control with switching device but all these methodologies require human assistance. In this project an automatic water level control for both overhead and underground tank with switching device is designed using electronic control to refill the water without human intervention.The system design was carefully arranged to refill the water tank when the water is get low to a certain level. Also the system automatically shut down the water pump by putting the electric pump OFF when the tank is full. The approach used in this work is the modular design approach the overall design was broken into function block diagrams. Where each block in the diagram represents a section of the circuit that carries out a specific function.The system was designed using functional blocks as shown in the block diagram bellow in this method the circuit is designed to display four different level using four sensors that inserted inside the tank in different places to monitor the inflow and outflow of water in the tank.This project designed for automatic water level controller for both overhead and underground tank with switching device. The major component used in the project designs are level detection sensors,micro-controller IC16F877A, the power supply unit, relays switch, indicator (LED) and RF transmitter and receiver.

3.1 Flow chart for project development The process involved in the development of the project is very important so that the process is smooth without any difficulties. The processes involved are under constant changes due to unexpected changes or complications.Flow of the development of the project is divided into two that are the hardware and software. The hardware part is divided into two parts that are the water sensor part and the output alarm part


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Figure 3.1: Flow Chart for Project Development

The project begins with literature reviews of the project. The literature reviews will investigate and

comment about the current water alarm detector in the market. The literature reviews will help to

produce a project that is not yet available in the market.

After the literature review, the project will continue with the circuit design of the water alarm. With the information gotten from the literature review, the circuit can be design from various parts of

projects done. The combinations of all these circuitry from the literature review, a new circuit can be produced.A circuit simulation using software is done after the circuit design to ensure that the circuit can

work according to the required specifications. It is also to ensure that the current and voltage in the

circuit is not to large so that it will not spoil the circuit. If the simulation is successful, the project continues with hardware and software development.


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If not the circuit simulation is continued until it is successful. After the hardware is built and the

program is written, the hardware and program undergoes testing. If the testing is successful, the

project is demonstrated to the panel. However, if the testing fails, the hardware built and the program

written will be re-tested again until it is successful.

3.2 System block diagram

Figure 3.2 total block diagram representation of the project

3.2.1 Block diagram description

3.2.1.1 Microcontroller (pic16877A)Micro controller plays a vital role in our project. Microcontroller controls each and every peripheral

device connected to it. The microcontroller that we are using is reliable and best suited for our

project. many times we forget to switch off the motor pushing Water into the overhead tank in our

households. As a result, water keeps overflowing until we notice the overflow and switch the pump off.

As the overhead tank is usually kept on the topmost floor, it is cumbersome to go up frequently to


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check the water level in the overhead tank. Here‘s a wireless microcontroller-based water level

controller to solve this Problem. It controls ‗on‘ and ‗off‘ conditions of the motor depending upon

the level of water in the tank. The status is displayed on a LED. The circuit also protects the motor

from high voltages, low voltages, fluctuations of mains power and dry running.

The microcontroller majorly has 5 ports, namely A, B, C, D, and E. The ports A and E are generally used for analog to digital data conversion. The port D is generally used for data and control functions of LED and relay. The port B has internal pull up resistors and hence there is no need to connect any more resistors with it. This port is used as the input port for the four level transistors switching

sensing system. This port is by default high, and hence is activated by ground signals.The port C has eight pins, of which pin 6 and 7 are used indication of water in the reservoir tank. The

port D of the pin 6 is used as the pump driver (relay).The controller is programmed to check the dry-run condition of the motor. If water reaches water indicator sensor in the sump tank, the microcontroller comes out of the dry-run condition and allows the motor to keep pushing water in the tank.When water in the tank is below sensor 1, the motor will switch on to fill water in the tank. The LED will show ‗motor on. The motor will remain ‗on‘ until water reaches sensor 4.Then it will stop automatically and the microcontroller will go into the standby mode.

The 16F877A is one of the most popular PIC microcontrollers and it's easy to see why - it comes in a 40 pin out and it has many internal peripherals. The 40 pins make it easier to use the peripherals as the functions are spread out over the pins. One of the main advantages is that each pin is only shared between two or three functions so it‘s easier to decide what the pin function (other devices have up to 5 functions for a pin).

Note: A disadvantage of the device is that it has no internal oscillator so you will need an external

crystal of other clock source.


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Figure 3.3 microcontroller PIC16F877A with pin configuration


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This makes it easier to decide what external devices to attach without worrying too much if there enough pins to do the job. One of the main advantages is that each pin is only shared between two or three functions so it‘s easier to decide what The 16F877A has 8k of code space, 368 bytes of RAM and 256 bytes of EEPROM.This device is pin-out and functionality compatible with the standard 16F877A.For 40MHz use, we can use an external 10MHz crystal with the Phased Locked Loop (PLL) option enabled. You can set this when programming your microcontroller. The PLL option multiplies the external clock frequency by four, giving an effective internal MCU speed of 40MH.

Figure 3.4 real outlook of microcontroller PIC16F877A

Input/output Ports of PIC 16F877A

PIC 16F877A series normally has five input/output ports. They are used for the input/output interfacing with other devices/circuits. Most of these port pins are multiplexed for handling alternate function for peripheral features on the devices. All ports in a PIC chip are bi-directional. When the

peripheral action is enabled in a pin, it may not be used as its general input/output functions. The PIC

16F877 chip basically has 5 input/output ports. The five input/output ports and its functions are given below.

PORT A and the TRIS A Registers

PORT A is a 6-bit wide bi-directional port, the direction of this port is controlled by TRIS A data

direction register. Setting a TRIS A (=1) makes corresponding PORT A pin as an input, clearing the TRIS A (=0) making the corresponding PORT A pin as an output Pin RA4 is multiplexed with the ―Timer0 ‖ module clock input to become the RA4/T0CKI pin and functioning either input/output operation or Timer 0 clock functioning module. The RA4/T0CKI pin is a Schmitt Trigger input and an open-drain output. All other PORT A pins has TTL input levels and full CMOS output drivers.

Other PORT pins in this microcontroller multiplexed with analog inputs and the analog VREF input for both the A/D converters and the comparators. The operation of each pin is selected by

clearing/setting the appropriate control bits in the ADCON1 and/or CMCON registers. The TRIS A


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register controls the direction of the PORT pins even when they are being used as analog inputs. The user must ensure the bits in the TRISA register are maintained set when using them as analog inputs. PORT B and the TRIS Registers

PORT B is also an 8 bit bi-directional PORT. Its direction controlled and maintained by TRIS B data direction register. Setting the TRIS B into logic ‗1‘ makes the corresponding ―PORT B ‖ pin as an input. Clearing the TRIS B bit make PORT B as an output. Three pins of PORT B are multiplexed with the In-Circuit Debugger and Low-Voltage Programming function: RB3/PGM, RB6/PGC and RB7/PGD for

performing its alternate functions.

PORT C and the TRIS C Registers

PORT C is an 8-bit wide, bidirectional PORT which controlled and maintained by TRIS C data direction register. Setting a TRIS C bit (= 1) will make the corresponding PORT C pin an input (i.e., put the corresponding output driver in a High-Impedance mode). Clearing a TRIS C bit (= 0) willmake the corresponding PORT C pin an output PORT C is also multiplexed with several peripheral functions.PORT C pins have Schmitt Trigger input buffers.When enabling peripheral functions, more care should be taken in defining TRIS bits for each PORT C

pin as compared to other. Some peripherals override the TRIS bit to make a pin an output, while other

peripherals override the TRIS bit to make a pin an input. Since the TRIS bit override is in effect while the peripheral is enabled, read-modify write instructions (BSF, BCF, and XORWF) with TRISC as the destination, should be avoided. The user should refer to the corresponding peripheral section for the correct TRIS bit settings.

PORT D and TRIS D Registers

PORT D is an 8-bit PORT with bi-directional nature. This port also with Schmitt Trigger input buffers,each pin in this PORT D individually configurable as either input or output. PORT D can be configured as an 8-bit wide microprocessor PORT (functioning as Parallel Slave PORT) by setting control bit,

PSPMODE ((TRISE). In this mode, the input buffers are TTL. PORT E and TRIS E Registers

PORT E has only three pins (RE0/RD/AN5, RE1/WR/AN6 and RE2/CS/AN7) which are individually configurable as inputs or outputs. These pins controllable by using its corresponding data direction register ―TRIS E ‖. These pins also have Schmitt Trigger input buffers. The PORT E pins become the I/O control inputs for the microprocessor PORT when bit PSPMODE is set. In this mode, the user must make certain that the TRIS E bits are set and that the pins are configured as digital inputs. Also,ensure that ADCON1 is configured for digital I/O. In this mode, the input buffers are TTL.

TRISE register which also controls the Parallel Slave PORT operation. PORT E pins are multiplexed with analog inputs. When selected for analog input, these pins will read as ‗0‘s. TRIS E controls the


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direction of the RE pins, even when they are being used as analog inputs. The user must make sure to

keep the pins configured as inputs when using them as analog inputs.

3.2.1.2 Water tankOverhead and sump tank This is the tank inside which the level of the liquid has to be controlled. Water is pumped to the tank

from the reservoir using water pump motor, water coming down into the tank. The probes used as a

sensor inserted inside the tank at different levels used to determine liquid level to measures the

height of the water in the tank. The microcontroller controls the pump so that the water is stopped at

the desired level. The tank used in this project is a plastic container.

3.2.1.3 Motor pumpThe pump is a small 120V water pump which draws around 16A current when it operates at the full-

scale voltage. The pump control segment consists of a 10k resistor diode, an NPN transistor and 12Vdc

relay. The 220Vac is attached to the common of the relay while the pump is attached to the normally

open pin of the relay. A diode is connected across the energizing coil of the relay to bias the relay

while the microcontroller controls the biasing of the relay by sending logic 1 or logic 0 to the base of

the NPN transistor, which in turn biases the relay.

Figure 3.5 motor driving relay circuit

3.2.1.4 Level sensorsThe level is sensed with a conducting metal strip. It works on the principle of electrical conducting

property of water. The sensing system used is based on transistor switching principle. The base of a transistor, connected to a resistor, is given at a certain level inside the tank and the base of the tank has 5V Vcc.


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The RF transmitter Vcc part is connected to the collector of the transistor. The emitterof the

transistor is grounded which is the ground of the transmitter. When the water level has not reached

the level at which the transistor base line is attached, the circuit is open and hence, there is no

current to the base. The transistor is now in cut off condition with no collector current and the entire

voltage is across the transistor. When the water comes in contact with the base line of the transistor,

the switch is closed and collector to emitter voltage becomes negligible and there is a collector

current. This change in voltage is considered by the RF transmitter and the current level is sensed. In

order to detect the various levels across the tank, four such circuits are present to detect four different levels. It should be noted that the number of levels can be increased or decreased as and if

required. Fig. shows the circuit diagram for sensing one level. The same circuit has been developed

four times for four levels

wire less microcontroller based liquid pump

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