ZEROS OF ENTIRE FOURIER TRANSFORMS ∗ Dimitar K. Dimitrov and Peter K. Rusev 0. Prime
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WATER LEVEL CONTROLLER
ABSTRACT
As the earth contains 3/4th of water resources, only 3% of water is in the form of fresh water. Over that 2/3rd of it is present in the frozen in glaciers and polar ice caps. The remaining unfrozen fresh water is mainly found as ground water, with only a small fraction present above the ground or in the air.
The factors like storage capacity in lakes, wetlands and artificial reservoirs, the permeability of the soil beneath these storage bodies. Human activities have a large and sometimes devastating impact on these factors , all of these factors also affect the proportions of water lost. It will happen for some more years all fresh water will be vanished on earth. As we have less fresh water it’s our responsibility to save water resources for our future generation.
The project “WATER LEVEL CONTROLLER” aims to monitor water level in the over head tanks and the main objective is to save fresh water which is wasted in our day to day life. This project has various practical applications in renewable of water resource in our own local site.
GPCET 1 Department Of ECE
WATER LEVEL CONTROLLER
CONTENTS: Page
i. List of Figures
ii. List of Tables
Chapters
1.1 Introduction
1.2 Block Diagram
2. Circuit description
Integrated Circuits
3. Circuit Operation
4. Applications
Advantages
Disadvantages
5. Result
6. Future
7. Conclusion
8. Appendices
A Cost Details
B References
C Photo copies
Index
LIST OF FIGURES
GPCET 2 Department Of ECE
WATER LEVEL CONTROLLER
1.1
LIST OF TABLUR COLOUMNS
GPCET 3 Department Of ECE
WATER LEVEL CONTROLLER
FIELD OF THE INVENTION
The "Automatic, Liquid/Water Level Controller", hereafter called
"Automatic Water Level Controller", works on the principle of monitoring and
controlling the liquid level in one or more over head tanks (or similar storage units)
and automatic pumping of liquid (such as water, etc.), for refilling such storage
tank(s), when the liquid level in these storage tank(s) hits set lower threshold level.
The uniqueness of this invention comes from the fact that the
operation of this automatic pumping system uses many novel methods. It uses a novel
method, hereafter called, "water level controller", the sensors that are used for
controlling the pumping operation to refill the overhead tank.
GPCET 4 Department Of ECE
WATER LEVEL CONTROLLER
Chapter - 1
INTRODUCTION
Storing water in one or more storage tanks (or similar storage units) kept on
top of buildings or at a convenient height is known for centuries. Such storage tanks
are also called "overhead tanks". Normally, the water to fill these storage tanks is
obtained from a tube well, an underground storage tank (also called sump tank), or
any natural reservoir. In all such cases, the storage tank is kept at a level that is higher
than the highest water level of the water source used for filling the tank. The stored
water is normally drawn from the overhead storage tank towards the gravity through
one or more outlets routed in and around the buildings, terminated by faucets (also
called taps), control valves at desired places.
There are many types of pumping systems available to pump the water to
replenish (refill) the overhead tank(s). Electric power operated motorized pumping is
generally the preferred choice. An impeller operated by an electric motor lifts the
water up to the required height. In the absence of the electric supply, water pumps
driven by Internal Combustion engine, steam engine, solar power, storage battery, etc.
can be used. Depending on the height of the overhead tank from the source of the
water, submersible pump, vacuum pump, or jet pump is used. In case of vacuum
pumps, the water is lifted due to continuous vacuum created by the rotating
movement of impeller that causes the displacement of air. In case of submersible
pumps, the pump is immersed in the water and the water is directly pushed up thereby
lifting the water through the pipe to the desired height to fill the overhead tanks.
With the increase in height of the buildings and deepening underground water
column, efficient pumping of water by automatic means are being developed. Such
automatic pumping systems use wired water level detection sensors for detecting the
water level in over head storage unit (tank) and, optionally, underground storage
reservoir to automatically control and operate the water pump to refill the overhead
tank. Also, increase in height of the buildings or the distance between tank and motor
GPCET 5 Department Of ECE
WATER LEVEL CONTROLLER
power control panel calls for using very large length of multi-core cables (wires) from
various sensors to the main power control panel.
This method can complement or replace the existing pumping techniques that use
manual operation or automatic pumping that uses wired water level detection sensors.
Further, this method can also be used to pump water for a long distance with the use
of long distance wireless data communication or one or more repeaters placed in
between transmitters and main control station. The use of the "Automatic Water Level
Controller” is limitless when the application area is considered.
For clarity and ease of explanation, pumping of water from an underground
storage tank (source) to an overhead tank is considered here. However, the source of
water can be from a tube well, a well, an underground reservoir (sump), or any other
means. Water pumped from a source can be stored in an overhead tank placed in a
neighborhood or on the roof top of a building such that the tank is kept at a level
higher than that of the highest water level of the water source used to fill the overhead
tank .
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1.1 BLOCK DIAGRAM
The block diagram of the Water Level Controller is depicted below:
figure:
Fig 1.1: Block diagram of Water Level Controller
Block Diagram Description:
The block diagram of Water Level Controller shown in figure 1.1 has five
main blocks. They are explained brefily:
Overhead tank:
The input stage mainly consisting of overhead tank that is used to store water
which is pumped from sump.
IC555 Timer:
555 TIMER is a most versatile liner integrated circuit, introduced by
SIGNETICS CORPORATION. It is operated in three modes namely mono stable,
astable, bistable.Based on our application its operated in “Monostable
Multivibrator”.
Power Amplifier:
Power amplifiers are used to deliver a relatively high amount of power,
usually to a low resistance load. Typical output power rating of a power amplifier will
be 1W or higher. Typical load values range from 300W (for transmission antennas) to
8W (for audio speaker).
GPCET 7 Department Of ECE
OVER HEAD TANK
IC 55 TIMER
POWER AMPLIFIER
RELAY
PUMP MOTOR
WATER LEVEL CONTROLLER
Relay:
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.
Motor:
A motor is a device that converts electrical energy into mechanical energy, very
typically through the interaction of magnetic fields and current-carrying conductors.The operation is
based on simple electromagnetism. It pumps the water form underground tank to overhead
tank
GPCET 8 Department Of ECE
WATER LEVEL CONTROLLER
Chapter – 2
CIRCUIT DESCRIPTION
The water level controller circuit is quite simple and it majorly consists of
IC555 timer, power amplifiers and motor which plays a major role in providing the
output. Along with these the circuit consists of a resistors, capacitor, diode and relay.
The Water Level Controller circuit diagram is depicted in the figure
Fig 2.1: water level controller circuit diagram
Before knowing about the operation of the circuit one must gain a brief
knowledge about the elements of the circuit and these are explained in detail in this
chapter. As I mentioned earlier, the IC and the motor plays a major role, they will be
discussed first and the remaining will be explained in the later topics.
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2.1 INTEGRATED CIRCUITS
The IC’s (acronym for Integrated Circuits) are now ruling the present
generation of electronics, it meant that we cannot imagine the electronic world
without the IC as it is involved in almost every electronic equipment. Hence it’s a
need to know what generally an IC is.
An integrated circuit (also known as IC, chip, or microchip) is a miniaturized
electronic circuit (consisting mainly of semiconductor devices, as well as passive
components) that has been manufactured in the surface of a thin substrate of
semiconductor material. Integrated circuits are used in almost all electronic equipment
in use today and have revolutionized the world of electronics. Computers, cellular
phones, and other digital appliances are now inextricable parts of the structure of
modern societies, made possible by the low cost of production of integrated circuits.
The ICs which are presently in the market are very much developed than that
of the ICs that are in the earlier decades. The IC development did not take place in a
single day by a single person, many experts involved in the development of ICs from
the beginning when the diode is first invented. The history of the IC’s is briefly noted
in the following lines in order to bring some knowledge about the evolution of ICs
from its beginning.
1940s - setting the stage
The initial inventions that made integrated circuits possible. The PN
diode and the Transistor were invented in this decade.
1950s - the invention of the integrated circuit
In this decade the transistor developed and invension of IC took place.
1954 – First commercial silicon transistor
1958 – Integrated circuit invented
1960s - product and technology advances
The advancement technolgy made to ivent the first MOS IC.
1969 – First commercial IC
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1963 – CMOS invented
1969 – BiCOMS invented
1970s - invension of new products
The developments in the CMOS technology lead to the invension of
new products like EPROM, DSP, DRAMs and Microprocessors.
1971 – Microprocessor invented
1978 – Intel 8086/8088
1980s - advancement of technology
The CMOS still developed to EEPROM and Flash and intel
introduced first 32 bit microprocessor.
1982 – Intel 80286
1983 – EPROM invented
1985 - Intel 80386DX
1989 - Intel 80486DXTM
1990s - further refinements in technology
The Intel still developed its microprocesor products, and the number
of transistors used per IC increased rapidly in this decade.
1993 – Intel Pentium
1994 - 64Mbit DRAM
1997 - Intel Pentium IITM
1999 - Intel Pentium IIITM
2000s - technolgy at the supreme
The technolgy rocked like anything in this decade, the Intel introduced
the high speed operating microprocessors like “core 2 duo”.
2000 - Intel Pentium 4TM
2007 - Intel Core 2 Duo
Thus the IC in the electronics became a major part and due to the
advancements in technology the number of transistors per IC is increasing
rapidly.
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WATER LEVEL CONTROLLER
2.2 A DETAIL STUDY OF IC 555 TIMER
IC555 TIMER:
555 TIMER is a most versatile liner integrated circuit, introduced by SIGNETICS
CORPORATION. The 555 is a monolithic timing circuit that can produce accurate
and highly stable time delays or oscillations. NE555 monolithic timing circuit is a
highly stable controller capable of producing accurate time delays or oscillation. In
the time delay mode of operation, the time is precisely controlled by one external
resistor and capacitor. For a stable operation as an oscillator, the free running
frequency and the duty cycle are both accurately controlled with 2 external resistors
and one capacitor.
Depending on the manufacturer, the standard 555 package includes over 20
transistors, 2 diodes and 15 resistors on a silicon chip installed in an 8-pin mini dual-
in-line package (DIP-8) Variants available include the 556 (a 14-pin DIP combining
two 555s on one chip), and the 558 (a 16-pin DIP combining four slightly modified
555s with DIS & THR connected internally, and TR falling edge sensitive instead of
level sensitive).
The 555 has three operating modes:
Monostable mode: in this mode, the 555 functions as a "one-shot". Applications
include timers, missing pulse detection, bouncefree switches, touch switches,
frequency divider, capacitance measurement, pulse-width modulation (PWM) etc
Astable - free running mode: the 555 can operate as an oscillator. Uses include LED
and lamp flashers, pulse generation, logic clocks, tone generation, security alarms,
pulse positon modulation, etc.
Schematic symbol:
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WATER LEVEL CONTROLLER
Fig 3.1.1 schematic diagram
The connection of the pins is as follows:
S.No Name Purpose
1 GND Ground, low level (0 V)
2 TRIG A short pulse high-to-low on the trigger starts the timer
3 OUT During a timing interval, the output stays at +VCC
4 RESET A timing interval can be interrupted by applying a reset pulse to low (0 V)
5 CTRL Control voltage allows access to the internal voltage divider (2/3 VCC)
6 THR The threshold at which the interval ends (it ends if the voltage at THR is at
least 2/3 VCC)
7 DIS Connected to a capacitor whose discharge time will influence the timing
interval
8 V+,
VCC
The positive supply voltage which must be between 3 and 15 V
Table1. 555 timer pin specifications
The internal diagram for a 555 timer is shown in the figure.
Pin1: Ground. All voltages are measured with respect to this terminal.
Pin2: Trigger. The output of the timer depends on the amplitude of the external
trigger pulse applied to this pin. The output is low if the voltage at this pin is greater
than 2/3 VCC. When a negative going pulse of amplitude greater than 1/3 VCC is
applied to this pin, comparator 2 output goes low, which in turn switches the output of
the timer high. The output remains high as long as the trigger terminal is held at a low
voltage.
Pin3: Output. There are two ways by which a load can be connected to the output
terminal: either between pin 3 and ground or between pin3 and supply voltage +VCC.
When the output is low the load current flows through the load connected between
pin3 and +VCC into the output terminal and is called sink current. The current
through the grounded load is zero when the output is low. For this reason the load
connected between pin 3 and +VCC is called the normally on load and that connected
between pin 3 and ground is called normally off-load. On the other hand, when the
output is high the current through the load connected between pin 3 and +VCC is
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zero. The output terminal supplies current to the normally off load. This current is
called source current. The maximum value of sink or source current is 200mA.
Pin4: Reset. The 555 timer can be reset (disabled) by applying a negative pulse to this
pin. When the reset function is not in use, the reset terminal should be connected to
+VCC to avoid any possibility of false triggering.
Pin5: Control Voltage. An external voltage applied to this terminal changes the
threshold as well as trigger voltage. Thus by imposing a voltage on this pin or by
connecting a pot between this pin and ground, the pulse width of the output waveform
can be varied. When not used, the control pin should be bypassed to ground with a
0.01µF Capacitor to prevent any noise problems.
Pin6: Threshold. This is the non-inverting input of comparator 1, which monitors the
voltage across the external capacitor. When the voltage at this pin is greater than or
equal to the threshold voltage 2/3 VCC, the output of comparator 1 goes high, which
inturn switches the output of the timer low.
Pin7: Discharge. This pin is connected internally to the collector of transistor Q1.
When the output is high Q1 is OFF and acts as an open circuit to external capacitor C
connected across it. On the other hand, when the output is low, Q1 is saturated and
acts as a short circuit, shorting out the external capacitor C to ground.Pin8: +VCC.
The supply voltage of +5V to + 18V is applied to this pin with respect to ground.
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555 TIMER AS MONOSTABLE MULTIVIBRATOR:
Monostable multivibrator often called as one shot multivibrator is a pulse generating
circuit in which the duration of this pulse is determined by the RC network connected
externally to the 555 timer. In a stable or standby state, the output of the circuit is
approximately zero or a logic-low level.
When external trigger pulse is applied
output is forced to go high ( VCC). The
time for which output remains high is
determined by the external RC network
connected to the timer. At the end of the
timing interval, the output automatically
reverts back to its logic-low stable state.
The output stays low until trigger pulse is
again applied. Then the cycle repeats. The
monostable circuit has only one stable state (output low) hence the name monostable.
Operation:
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Initially when the circuit is in the stable state i.e , when the output is low, transistor
Q1 is ON and the capacitor C is shorted out to ground. Upon the application of a
negative trigger pulse to pin 2, transistor Q1 is turned OFF, which releases the short
circuit across the external capacitor C and drives the output high. The capacitor C
now starts charging up towards VCC through R. When the voltage across the
capacitor equals 2/3 VCC, comparator 1’s output switches from low to high, which
inturn drives the output to its low state via the output of the flip-flop. At the same time
the output of the flip-flop turns transistor Q1 ON and hence the capacitor C rapidly
discharges through the transistor. The output of the monostable remains low until a
trigger pulse is again applied. Then the cycle repeats.
The pulse width of the trigger input must be smaller than the expected pulse width of
the output waveform. Also the trigger pulse must be a negative going input signal
with amplitude larger than 1/3 VCC.
The time during which the output remains high is given by
GPCET 16 Department Of ECE
T=1.1RC seconds
WATER LEVEL CONTROLLER
where R is in Ohms and C is in Farads.
Once triggered, the circuit’s output will remain in the high state until the set time, t
elapses. The output will not change its state even if an input trigger is applied again
during this time interval t. The circuit can be reset during the timing cycle by applying
negative pulse to the reset terminal. The output will remain in the low state until a
trigger is again applied.
Fig 3.4.2 waveforms of monostable multivibrat.
Specifications: The different specifications of IC555 Timer:
Supply voltage (VCC) 4.5 to 15 V
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Supply current (VCC = +5 V) 3 to 6 mA
Supply current (VCC = +15 V) 10 to 15 mA
Output current (maximum) 200 mA
Maximum Power dissipation 600 mW
Power Consumption (minimum
operating) 30 mW@5V, 225 mW@15V
Operating temperature 0 to 70 °C
A BRIEF STUDY OF PUMP MOTOR:
The principle of motor:
Motors convert electrical energy (from a battery or voltage source) into mechanical energy (used to cause rotation).When a wire that carries current is placed in a region of space that has amagnetic field, the wire experiences a force.The size of the force, which determines how fast the motor spins, depends on : o the amount of current in the wire o the length of the wire o the strength of the magnetic field
Force = (current) x (wire length) x (magnetic
field)
The direction of the force, which determines which direction the motor spins,depends on: o the direction of the current in the wire o the direction of the magnetic field
GPCET 18 Department Of ECE
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The Right Hand Rule is used to determine the direction of the force when the direction of the current and the direction of the magnetic field are known.
DC Motor:
DC motor, operation is based on simple electromagnetism. Acurrent- carrying conductor generates a magnetic field; when this is then placed in an external magnetic field, it will experience a force proportional to thecurrent in the conductor, and to the strength of the external magnetic field. opposite (North and South) polarities attract, while like polarities (North and North, South and South) repel. The internal configuration of aDC motor is designed to harness the magnetic interaction between a current-carrying conductor and an external magnetic field to generate rotational motion.
EveryDC motor has six basic parts -- axle, rotor (a.k.a., armature), stator, commutator, field magnet(s), and brushes. In most common DC motors the external magnetic field is produced by high-strength permanent magnets1. The stator is the stationary part of the motor -- this includes the motor casing, as well as two or more permanent magnet pole pieces. The rotors (together with the axle and attached commutator) rotate with respect to the stator. The rotor consists of windings (generally on a core), the
GPCET 19 Department Of ECE
Thumb = direction of currentFingers = dir. of magnetic fieldPalm = direction of force
WATER LEVEL CONTROLLER
windings being electrically connected to the commutator. The above diagram shows a common motor layout -- with the rotor inside the stator (field) magnets.
Structure of a Water Pump Motor: A water pump motor is a disc shaped, conical device made of hard-wearing steel and aluminum. It's hollow, containing a circular interior chamber with a series of paddle-like protrusions extending from a central spindle. The water pump motor usually sits near the front of the car's engine, bolted into place either against the engine or the engine mounting. Hoses connect the water pump motor to the radiator as well as to a network of pipes running in a closed circuit through the engine itself. The central spindle extends out from the closed interior of the water pump motor to connect by means of a fan belt to the engine's output.
The geometry of the brushes, commutator contacts, and rotor windings are such that when power is applied, the polarities of the energized winding and the stator magnet(s) are misaligned, and the rotor will rotate until it is almost aligned with the stator's field magnets. As the rotor reaches alignment, the brushes move to the next commutator contacts, and energize the next winding. Given our example two-pole motor, the rotation reverses the direction ofcurrent through the rotor winding, leading to a "flip" of the rotor's magnetic field, driving it to continue rotating.
A BRIEF STUDY OF TRANSISTOR(SL100):
SL100 is a general purpose, medium power NPN transistor. It is mostly used as
switch in common emitter configuration. The transistor terminals require a fixed DC
voltage to operate in the desired region of its characteristic curves. This is known as
the biasing. For switching applications, SL100 is biased in such a way that it remains
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fully on if there is a signal at its base. In the absence of base signal, it gets turned off
completely.
The emitter leg of SL100 is indicated by a protruding edge in the transistor case. The
base is nearest to the emitter while collector lies at other extreme of the casing.
Pin Diagram:
POWERAMPLIFIER:
Power amplifiers are used to deliver a relatively high amount of power, usually to a
low resistance load.Typical load values range from 300W (for transmission
GPCET 21 Department Of ECE
WATER LEVEL CONTROLLER
antennas) to 8W (for audio speaker). Although these load values do not cover every
possibility, they do illustrate the fact that power amplifiers usually drive low-
resistance loads. Typical output power rating of a power amplifier will be 1W or
higher. Ideal power amplifier will deliver 100% of the power it draws from the
supply to load. In practice, this can never occur. The reason for this is the fact that the
components in the amplifier will all dissipate some of the power that is being drawn
form the supply.
Automatic gain control (AGC) is an adaptive system found in many electronic
devices. The average output signal level is fed back to adjust the gain to an
appropriate level for a range of input signal levels and also the amplitude of an
incoming signal can vary over a wide dynamic range. The role of the AGC circuit is
to provide a relatively constant output amplitude so that circuits following the AGC
circuit require less dynamic range.
Output of AGC is given to the Band pass Filter to allow the band of frequencies to the
Demodulator circuit. Some part of the signal is fed back to the AGC through Control
circuit from Band pass filter and Demodulator , and then the output is given to the
pin’s through transistor.
AMPLIFIER CLASSIFICATIONS:
• Power amplifiers are classified according to the percent of time that collector
current is nonzero.
• The amount the output signal varies over one cycle of operation for a full
cycle of input signal.
EFFECIENCY RATINGS:
Amplifier Maximum Theoretical Efficiency, hmax
Class A 25%
Class B 78.5%
Class C 99%
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LIMITATION:
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Device specifications:
Type SL100
Polarity NPN
Application General purpose medium transistor
Package To-39
Maximum ratings:
CHARACTERISTICS SYMBOL MIN MAX UNIT
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Collector-Emitter Voltage
Collector-Base Voltage
Emitter-Base Voltage
Total Power Dissipation
@TA=25°C
Collector Current
Operating and Storage
Temperature Junction
BVCEO
BVCBO
BVEEO
PD
IC
Tj,Tstg
50
60
5.0
-
-
-
800
0.5
-65 to200
V
V V
mW
A
°C
A BRIEF STUDY OF RELAYS:
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 most have double throw (changeover) switch contacts as shown in the diagram.
The relay's switch connections are usually labelled COM, NC and NO:
COM = Common, always connect to this, it is the moving part of the switch. NC = Normally Closed, COM is connected to this when the relay coil is off. NO = Normally Open, COM is connected to this when the relay coil is on. Connect to COM and NO if you want the switched circuit to be on when the
relay coil is on. Connect to COM and NC if you want the switched circuit to be on when the
relay coil is off.
Choosing a relay: You need to consider several features when choosing a relay:
1. Physical size and pin arrangement If you are choosing a relay for an existing PCB you will need to ensure that its dimensions and pin arrangement are suitable. You should find this information in the supplier's catalogue.
2. Coil voltage The relay's coil voltage rating and resistance must suit the circuit powering the
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relay coil. Many relays have a coil rated for a 12V supply but 5V and 24V relays are also readily available. Some relays operate perfectly well with a supply voltage which is a little lower than their rated value.
3. Coil resistance The circuit must be able to supply the current required by the relay coil. You can use Ohm's law to calculate the current:
Relay coil current = supply voltage coil resistance
4. Switch ratings (voltage and current) The relay's switch contacts must be suitable for the circuit they are to control. You will need to check the voltage and current ratings. Note that the voltage rating is usually higher for AC, for example: "5A at 24V DC or 125V AC".
5. Switch contact arrangement (SPDT, DPDT etc) Most relays are SPDT or DPDT which are often described as "single pole changeover" (SPCO) or "double pole changeover" (DPCO). For further information please see the page on switches.
Protection diodes for relays
Transistors and ICs must be protected from the brief high voltage produced when a relay coil is switched off. The diagram shows how a signal diode (eg 1N4148) is connected 'backwards' across the relay coil to provide this protection.
Current flowing through a relay coil creates a magnetic field which collapses suddenly when the current is switched off. The sudden collapse of the magnetic field induces a brief high voltage across the relay coil which is very likely to damage transistors and ICs. The protection diode allows the induced voltage to drive a brief current through the coil (and diode) so the magnetic field dies away quickly rather than instantly. This prevents the induced voltage becoming high enough to cause damage to transistors and ICs.
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Advantages of relays:
Relays can switch AC and DC, transistors can only switch DC. Relays can switch higher voltages than standard transistors. Relays are often 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.
2.6 A BRIEF STUDY OF DIODE 1N4001
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Description:
The 1N4001 diodes are a popular 1.0 amp general purpose rectifier family,
commonly used in AC adapters for common household appliances. Blocking voltage
varies from 50-1000V. Comes in an axial-lead DO-41 plastic package. These are
fairly low speed rectifier diodes.
Figure2.5.1: Picture of diode 1N4001
Features:
• Diffused Junction.• High Current Capability and Low Forward Voltage Drop.• Surge Overload Rating to 30A Peak.• Low Reverse Leakage Current.
Specifications:
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Characteristic Symbol IN4001 Unit
Peak Repetitive Reverse VoltageWorking Peak Reverse VoltageDC Blocking Voltage
VRRMVRWMVR
50 V
RMS Reverse Voltage VR(RMS) 35 V
Average Rectified Output
Current (Note 1) @ TA =
75°C
IO 1.0 A
Non-Repetitive Peak Forward Surge Current 8.3mssingle half sine-wave
superimposed on rated load
IFSM 30 A
Forward Voltage @ IF =
1.0A
VFM 1.0 V
Peak Reverse Current @TA = 25°Cat Rated DC Blocking
Voltage @ TA = 100°C
IRM 5.050
μA
Typical Junction
Capacitance (Note 2)
Cj 15 8 pF
Maximum DC Blocking
Voltage Temperature
RθJA 100 K/W
Maximum DC Blocking
Voltage Temperature
TA +150 °C
Operating and Storage
Temperature Range
TJ, TSTG -65 to +150 °C
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Chapter – 3
CIRCUIT OPERATION:
Similarly,when the water level goes down, the moving contacts revert back to their original positions. Normally, N/C contact of switch S1 is connected to ground and N/C contact of switch S2 is connected to 12V power supply. IC 555 is wired such that when its trigger pin 2 is grounded it gets triggered, and when reset pin 4 is grounded it gets reset. Threshold pin 6 and discharge pin 7 are not used in the circuit. When water in the tank goes below the minimum level, moving contacts of both leaf switches will be in N/C position. That means trigger pin 2 and reset pin 4 of IC555 timer are connected to ground and 12V, respectively. This triggers IC555 timer and its output goes high to energise relay through driver transistor SL100. The pump motor is switched on and it starts pumping water into the overhead tank. As the water level in the tank rises, the float of sensor 1 goes up. This shifts the moving contact of switch S1 to N/O position and trigger pin 2 of IC555 timer gets connected to 12V. This doesn’t have any impact on IC555 timer and its output remains high to keep the pump motor running. As the water level reaches the maximum level, the float of sensor 2 pushes the moving contact of switch S2 to N/O position and it gets connected to ground. Now IC555 timer is reset and its output goes low to switch the pump off.
GPCET 30 Department Of ECE
WATER LEVEL CONTROLLER
Chapter - 4
APPLICATIONS
The water level controller has many practical apllications which are mentioned below:
APPLICATIONS:
The circuit can be implemented in house for effective usage of water and electricity.
It can be used in municipal corporation to pump motor.
Figure 4.1: Practical application of water level controller
It can be implemented in large industries, hotels, educational institutions, hospitals, apartments etc.
GPCET 31 Department Of ECE
WATER LEVEL CONTROLLER
ADVANTAGES:
Easy installation. Low maintenance. Fully Automatic. Compact elegant design. Save water, motor and energy. Increases pumpset life. Avoid seepage of roofs & walls due to overflowing tanks. Avoid dry running of water tanks.
DISADVANTAGES:
Make sure that Water being delivered from the water pipe doesn’t touch
any of the suspended water.
Mount the sensor firmly onto the water pipe such that switches S1and S2 are
shorted by water flowing out of the pipe.
Use a properly shielded cable of carry signals from the tank to the water –
level controller circuit.
Frequent observation of water in underground water.
When power fails.
Future scope:
By replacing the IC 555 Timer we use Micro processor in order to run
the motor in an efficient manner.
It can be used in any industries concerned with fluids.
Buy placing LED’s in the sump and inverter we can over come some of the
disadvantages.
GPCET 32 Department Of ECE
WATER LEVEL CONTROLLER
Chapter – 6
CONCLUSION:
By using water level controller we can avoid wastage of
water by the electronic device without any interference of
human.
The circuit of the water level controller is designed and the
suceesful working verified.
The project has been successfully completed and it
provides an opportunity to understand us about the PCB
fabrication design of the circuit and miscellanies
components.It also gives ability to do various other
complex designs.
GPCET 33 Department Of ECE
WATER LEVEL CONTROLLER
COST DETAILS:
GPCET 34 Department Of ECE
S.NO NAME OF COMPONENT VALUE PRICE
1. OP-AMP, IC1 CA3140 Rs.12
2. DISPLAY DRIVER, IC2 LM3915 Rs.30
3. VOLTAGE REGULATORS, IC3
IC4
7805
7809
Rs.5
Rs.5
4. DIODE, D1 1N34 Rs.4
5. TRANSISTOR, T1 BC557 Rs.2
6. CAPACITOR, C1 1μF, 25V Rs.2
7. RESISTORS, R1
R2
R3
R4
R5,R6,R7
47KΩ
47KΩ
470Ω
100Ω
1KΩ, 1KΩ, 1KΩ
Rs.1
Rs.1
Rs.0.5
Rs.0.5
Rs.1.5
8. VARIABLE RESISTORS, VR1
VR2
VR3
VR4
1KΩ
1MΩ
50KΩ
4.7KΩ
Rs.0.5
Rs.1
Rs.1
Rs.0.5
9. LEDs, RED & GREEN Rs.2
10. PIEZO BUZZER, PZ1 Rs.15
11. BATTERY 9V Rs.20
WATER LEVEL CONTROLLER
BIBLIOGRAPHY:
1. Operational amplifiers and linear integrated circuits by GAYAKWAD
2. www.electronicsforyou.com
3. http://www.circuitstoday.com/door-bell-circuit-using-um-66-
ic#ixzz0cmoR0q3H
4. http://en.wikipedia.org/wiki/Light-emitting_diode
5. http://en.wikipedia.org/wiki/555_timer_IC
6. http://www.circuitstoday.com/555-timer-as-monostable-multivibrator
GPCET 35 Department Of ECE
WATER LEVEL CONTROLLER
PHOTO COPIES
GPCET 36 Department Of ECE
WATER LEVEL CONTROLLER
INDEX
Absolute accuracy 24
Comparator gain 24
Display driver 8
Drop out voltage 24
Dynamic current sink 18
IC CA3140 12
Pin out 13
IC LM3915 19
Pin out 19
Input bias current 24
Integrated Circuit 10
Offset voltage 24
Rectifier 36
Relative accuracy 25
Ripple Voltage 39
Smoothing capacitor 37
Typical Bridge Rectifier 37
Variable Resistors 41
Voltage Regulator 27
7805 32
7809 33
GPCET 37 Department Of ECE