Solar-Powered Fire Detection System for Forests

In recent years, the escalating frequency and intensity of forest fires have posed a significant threat to
ecosystems, wildlife, and human settlements. Rapid detection of these fires is crucial to implementing timely
response measures and preventing widespread devastation. To address this challenge, the development of a
Solar-Powered Fire Detection System for forests emerges as a sustainable and efficient solution.
The primary objective of this project is to harness the power of solar energy to operate an intelligent and
autonomous fire detection system. By utilizing solar panels to generate electricity, the system becomes self-
sufficient and environmentally friendly, reducing its carbon footprint and ensuring continuous operation in
remote forest locations without access to a conventional power grid.

Key Components of the System:

1. ZERO PCB Zero PCB is basically a general-purpose printed circuit board (PCB), also known as
perfboard or DOT PCB. It is a thin rigid copper sheet with holes pre-drilled at standard intervals
across a grid with 2.54mm (0.1- inch) spacing between holes. Each hole is encircled by a round or
square copper pad so that component lead can be inserted into the hole and soldered around the
pad without short-circuiting the nearby pads and other leads. For connecting the lead of component
with another lead, solder these together or join these using a suitable conducting wire.

Veroboard or stripboard is also a general purpose PCB characterised by a 2.54mm regular

(rectangular) grid of holes, with parallel strips of copper cladding running in one direction across
one side of the board. This general-purpose PCB is known by the name of the original product,
Veroboard, a trademark of British company Vero Technologies Ltd and Canadian company Pixel
Print Ltd. Both zero PCB and veroboard are popular among hobbyists, beginners, and students for
rapid prototyping and project works.
2. ARDUINO NANO (MICROCONTROLLER) is Arduino's classic breadboard friendly designed board
with the smallest dimensions. The Arduino Nano comes with pin headers that allow for an easy
attachment onto a breadboard and features a Mini-B USB connector. The classic Nano is the oldest
member of the Arduino Nano family boards. It is similar to the Arduino Duemilanove but made for
the use of a breadboard and has no dedicated power jack. Successors of the classic Nano are for
example the Nano 33 IoT featuring a WiFi module or the Nano 33 BLE Sense featuring Bluetooth®
Low Energy and several environment sensors.
 I2CProtocol
A communication protocol that can be used to set up communication between two boards.
PROGRAMING CODE FOR ARDUINO NANO (yet to be done)
3. FLAME SENSOR A flame-sensor is one kind of detector which is mainly designed for detecting as
well as responding to the occurrence of a fire or flame. The flame detection response can depend on
its fitting. It includes an alarm system, a natural gas line, propane & a fire suppression system. This
sensor is used in industrial boilers. The main function of this is to give authentication whether the
boiler is properly working or not. The response of these sensors is faster as well as more accurate
compare with a heat/smoke detector because of its mechanism while detecting the flame.

Working Principle:- This sensor/detector can be built with an electronic circuit using a receiver like
electromagnetic radiation. This sensor uses the infrared flame flash method, which allows the sensor
to work through a coating of oil, dust, water vapor, otherwise ice.

Flame Sensor Module:- The pin configuration of this sensor is shown below. It includes four pins
which include the following. When this module works with a microcontroller unit then the pins are

• Pin1 (VCC pin): Voltage supply rages from 3.3V to 5.3V

• Pin2 (GND): This is a ground pin
• Pin3 (AOUT): This is an analog output pin (MCU.IO)
• Pin4 (DOUT): This is a digital output pin (MCU.IO)

Different Types:- Flame-sensors are classified into four types

 • IR single frequency
• IR multi-spectrum
• UV flame detectors
• UV/ IR flame detectors

Features & Specifications:- The features of this sensor include the following.
a) Photosensitivity is high
b) Response time is fast
c) Simple to use
d) Sensitivity is adjustable
e) Detection angle is 600
f) It is responsive to the flame range.
g) Accuracy can be adjustable
h) Operating voltage of this sensor is 3.3V to 5V
i) Analog voltage o/ps and digital switch o/ps
j) The PCB size is 3cm X 1.6cm
k) Power indicator & digital switch o/p indicator
l) If the flame intensity is lighter within 0.8m then the flame test can be activated, if the flame
intensity is high, then the detection of distance will be improved.

4. NPN TRANSISTOR

Definition: NPN transistor is a type of bipolar transistor that has 3 layers and is used for signal
amplification. It is a current controlled device. NPN is an abbreviation used for a negative positive
negative transistor. This means a p-type semiconductor is fused between 2 n-type semiconductor
material. It has 3 regions namely emitter, base and collector. The flow of electrons is responsible for
the conduction in NPN transistor.

The figure below shows the symbolic representation of the NPN transistor:

In the symbolic representation, the outward arrow at the emitter terminal clearly shows the direction
of flow of current through the device. In NPN transistor the majority carriers are electrons.

Construction of NPN transistor: As we are already familiar with the fact that NPN transistor is
formed when a p-type semiconductor material (either Silicon or Germanium) is fused between two
n-type semiconductor material. The figure below represents the constructional structure of NPN
transistor:

It has basically 3 regions i.e., emitter, base and collector. The junction region present between emitter
and base region is termed as the emitter-base junction. Similarly, the junction region between the
base and collector region is termed as the collector-base junction. Due to the presence of 2 junctions
in between 3 regions, it acts like 2 PN junction diodes. The doping levels of all the 3 regions are
different. The emitter region is highly doped; the base region is lightly doped. And the doping level
of collector region falls in between the emitter and base region or we can say its doping level is
moderate.
It is noteworthy here that we cannot interchange the emitter and collector region. The reason for this
is that the thickness of the collector region is somewhat greater than the emitter region. So, that it can
dissipate more power.

Working of NPN transistor

Let us now understand how NPN transistor operates. When the transistor is not provided with any
applied bias or when no battery is connected between its terminals. Then it is said to be the unbiased
state of the transistor. We have already discussed how a PN junction diode operates under no biased
condition. And we already know that a transistor is formed by two PN junction.
So, due to variation in temperature under no biased condition electrons in the emitter region starts
moving towards the base region. But, after a certain point of time a depletion region is created at the
emitter-base junction of the transistor. After reaching the base region, only around 5% of electrons
combine with the holes in this region, rest drift across the collector region. Similarly, here also after
some time a depletion region is created at the base-collector junction of the transistor.
It is to be noted here that the doping concentration of the material is responsible for the thickness or
thinness of the depletion region. More clearly, we can say that the width of the depletion region will
be more in the case of a lightly doped region in comparison to the highly doped region. This is the
reason why we achieve broader depletion width at the collector-base junction than the emitter-
base junction. These two depletion regions act as the potential barrier for any further flow of
majority carriers.
Moving further, let us now understand the case when a voltage is applied to the terminals of the
transistor. Generally, the emitter-base junction is provided forward dc voltage and the collector-base
junction is supplied with a reverse dc voltage.
The figure shows the biased condition of NPN transistor:
Due to the forward applied voltage at the emitter-base junction, the width of the depletion region gets
narrowed. Similarly, the reverse applied voltage broadens the width of the collector-base junction.
This is the reason why we have shown a thin depletion region at the emitter-base junction as compared
to the collector-base junction in the above figure.
Due to the forward applied voltage VBE, electrons start injecting into the emitter region. The
electrons in this region have sufficient energy by which it overcomes the barrier potential of the
emitter-base junction to arrive the base region.
The figure below represents that charge carrier movement in NPN transistor:

As the base region is very thin and lightly doped. So, after reaching there very few electrons get
combined with the holes. Due to the very thin base region and the reverse voltage at the collector-
base junction, electrons start to drift at the collector region because of the strong electrostatic field.
So, now these electrons get collected at the collector terminal of the transistor.
As recombined holes and electrons get separated from each other, the electrons start moving towards
collector. Due to this movement, a very small base current also flows through the device. This is
the reason why emitter current is the summation of base current and collector current.
IE = IB + IC

Applications of NPN transistor

➢ As NPN transistors are used for signal amplification. Thus used in amplifying circuits.
➢ It also finds its applications in logarithmic converters.
 ➢ One of the major advantages of NPN transistor is its switching characteristic. Thus widely
used in switching applications.
➢ These are also used in high-frequency applications.
➢ Key terms related to NPN transistor
➢ Emitter region: It is left the most section of the structure which has a size greater than base
region but less than collector region. It is highly doped. It is used to transfer majority carriers
i.e., electrons into the base region. It is a forward biased region that means it is always provided
forward biased with respect to the base region.
➢ Base region: The middle section of the structure is the base region. Its region is small as
compared to emitter and collector region of the transistor. It is lightly doped in order to have
minimum recombination so as to have large current at the collector.
➢ Collector region: It is the rightmost section of the structure and its functioning lies in its
name itself i.e., it collects the carriers transferred by the base region. Reverse biasing is
provided to this region w.r.t base region.
The operation of another type of bipolar transistor i.e., PNP is almost similar to NPN transistor.
However, the only variation lies in the majority carriers responsible for current flow and the biasing
arrangement provided to it.

5. BATTERY

A battery can be defined as an electrochemical device (consisting of one or more electrochemical

cells) which can be charged with an electric current and discharged whenever required. Batteries are
usually devices that are made up of multiple electrochemical cells that are connected to external
inputs and outputs. Batteries are widely employed in order to power small electric devices such as
mobile phones, remotes, and flashlights. Historically, the ‘term’ battery has always been used in order
to refer to the combination of two or more electrochemical cells. However, the modern definition of
the term ‘battery’ is believed to accommodate devices that only feature a single cell.

Batteries are broadly classified into two categories, namely primary batteries and secondary batteries.
Primary batteries can only be charged once. When these batteries are completely discharged, they
become useless and must be discarded. The most common reason why primary batteries cannot be
recharged is that the electrochemical reaction that takes place inside of them is irreversible in nature.
It is important to note that primary batteries are also referred to as use-and-throw batteries.
On the other hand, secondary batteries are the batteries than can be charged and reused for many
charging-discharging cycles. The electrochemical reactions that take place inside these batteries are
usually reversible in nature. Therefore, secondary batteries are also known as rechargeable batteries.
When discharging, the reactants combine to form products, resulting in the flow of electricity. When
charging, the flow of electrons into the battery facilitates the reverse reaction, in which the products
react to form the reactants.
The Lead-Acid Battery
The lead-acid battery is believed to have been invented by the French physicist and inventor Gaston
Planté in the year 1859. It is known to be one of the earliest rechargeable batteries. Despite the fact
that the lead-acid battery has a very high energy-to-volume ratio and also a very low energy-to-weight
ratio, the electrochemical cells in this battery are known to have a fairly large power-to-weight ratio.
This can be attributed to their ability to produce strong surge currents. These features of the lead-acid
battery, along with its relatively low cost, makes it highly desirable for use in motor vehicles and
automobiles in order to provide the high current required to start the engine.
Some key characteristics of the lead-acid battery are:
➢ It has the ability to hold an electric charge for up to 3 years.
➢ It is ideal for use as an emergency power backup.
➢ It is one of the most inexpensive batteries in its output range.
The Nickel-Cadmium Battery (also known as the NiCad Battery)
The nickel-cadmium battery (sometimes referred to as the ‘NiCad’ battery) is a type of rechargeable
battery that employs metallic cadmium and nickel oxide hydroxide as the electrodes o the battery.
The NiCad battery is known to offer varying discharge rates that are dependent on the size of the
battery itself. For example, the discharge rate (maximum) for a typical AA sized cell is approximately
equal to 1.8 amperes. On the other hand, the discharge rate for a D size battery can be as high as 3.5
amperes.
The key features of the NiCad battery are listed below.
➢ The nickel-cadmium battery features a very fast and even discharge of electrical energy.
➢ This type of battery is widely available and is also known to be relatively inexpensive.
➢ The NiCad battery can most commonly be found in certain toys and small electronic devices
such as TV remotes.
The Lithium-Ion Battery (also known as the LIB Battery)
The lithium-ion battery, often abbreviated to LIB, is a type of secondary battery which is
rechargeable. LIBs are known to have many applications in powering electric vehicles and is also
known to be used extensively in the aerospace industry.
Within the batteries, during the discharging process, lithium ions are known to pass from the negative
electrode to the positive electrode (through an electrolyte ). These lithium ions are also known to
travel back when charging. Lithium-ion batteries usually employ an intercalated lithium compound
in the positive electrode and usually graphite in the negative electrode as the fuel. Lithium-ion
batteries are highly desirable due to their high energy capacity, no memory effect (with the exception
of LFP cells), and low self-discharge.
Some key characteristics of LIBs are listed below.
 ➢ The lithium-ion battery is regarded to be one of the most stable and safe batteries. This battery
is also known to have a very high energy capacity.
➢ LIBs are widely used in mobile phones and portable computers (such as laptops and tablets).
➢ This battery has a very slow self-discharge. Furthermore, it is known to have twice the energy
capacity of the NiCad battery.

6. BUZZER
An audio signalling device like a beeper or buzzer may be electromechanical or piezoelectric or
mechanical type. The main function of this is to convert the signal from audio to sound. Generally, it
is powered through DC voltage and used in timers, alarm devices, printers, alarms, computers, etc.
Based on the various designs, it can generate different sounds like alarm, music, bell & siren.

The pin configuration of the buzzer is shown below. It includes two pins namely positive and
negative. The positive terminal of this is represented with the ‘+’ symbol or a longer terminal. This
terminal is powered through 6Volts whereas the negative terminal is represented with the ‘-‘symbol
or short terminal and it is connected to the GND terminal.
Specifications
The specifications of the buzzer include the following.
➢ Color is black
➢ The frequency range is 3,300Hz
➢ Operating Temperature ranges from – 20° C to +60°C
➢ Operating voltage ranges from 3V to 24V DC
➢ The sound pressure level is 85dBA or 10cm
➢ The supply current is below 15Ma

Types of Buzzer
A buzzer is available in different types which include the following.
 ➢ Piezoelectric
➢ Electromagnetic
➢ Mechanical
➢ Electromechanical
➢ Magnetic

Working Principle
The working principle of a buzzer depends on the theory that, once the voltage is given across a
piezoelectric material, then a pressure difference is produced. A piezo type includes piezo crystals
among two conductors.
Once a potential disparity is given across these crystals, then they thrust one conductor & drag the
additional conductor through their internal property. So, this continuous action will produce a sharp
sound signal.

7. SOLAR PANELS
A solar panel is a device that converts sunlight into electricity by using photovoltaic (PV) cells. PV cells
are made of materials that generate electrons when exposed to light. The electrons flow through a circuit
and produce direct current (DC) electricity, which can be used to power various devices or stored in
batteries. Solar panels are also known as solar cell panels, solar electric panels, or PV modules.

Solar panels are usually arranged in groups called arrays or systems. A photovoltaic system consists of
one or more solar panels, a inverter that converts DC electricity to alternate current (AC) electricity, and
sometimes other components such as controllers, meters, and trackers. A photovoltaic system can be used
to provide electricity for off-grid applications, such as remote homes or cabins, or to feed electricity back
into the grid and earn credits or payments from the utility company. This is called a grid-connected
photovoltaic system.
Some advantages of solar panels are that they use a renewable and clean source of energy, reduce
greenhouse gas emissions, and lower electricity bills. Some disadvantages are that they depend on the
availability and intensity of sunlight, require maintenance and cleaning, and have high initial costs. Solar
panels are widely used for residential, commercial, and industrial purposes, as well as for space and
transportation applications.
CONSTRUCTION :-
Photovoltaic modules consist of a large number of solar cells and use light energy (photons) from the
Sun to generate electricity through the photovoltaic effect. Most modules use wafer-based crystalline
silicon cells or thin-film cells. The structural (load carrying) member of a module can be either the top
layer or the back layer. Cells must be protected from mechanical damage and moisture. Most modules
are rigid, but semi-flexible ones based on thin-film cells are also available. The cells are usually
connected electrically in series, one to another to the desired voltage, and then in parallel to increase
current. The power (in watts) of the module is the mathematical product of the voltage (in volts) and the
current (in amperes), and depends both on the amount of light and on the electrical load connected to the
module. The manufacturing specifications on solar panels are obtained under standard conditions, which
are usually not the true operating conditions the solar panels are exposed to on the installation site.
A PV junction box is attached to the back of the solar panel and functions as its output interface. External
connections for most photovoltaic modules use MC4 connectors to facilitate easy weatherproof
connections to the rest of the system. A USB power interface can also be used. Solar panels also use
metal frames consisting of racking components, brackets, reflector shapes, and troughs to better support
the panel structure.
Arrays of PV modules
A single solar module can produce only a limited amount of power; most installations contain multiple
modules adding their voltages or currents. A photovoltaic system typically includes an array of
photovoltaic modules, an inverter, a battery pack for energy storage, a charge controller, interconnection
wiring, circuit breakers, fuses, disconnect switches, voltage meters, and optionally a solar tracking
mechanism. Equipment is carefully selected to optimize output, and energy storage, reduce power loss
during power transmission, and convert from direct current to alternating current.
Smart solar modules:-
Smart modules are different from traditional solar panels because the power electronics embedded in the
module offers enhanced functionality such as panel-level maximum power point tracking, monitoring,
and enhanced safety. Power electronics attached to the frame of a solar module, or connected to the
photovoltaic circuit through a connector, are not properly considered smart modules.[14]
Several companies have begun incorporating into each PV module various embedded power electronics
such as:
• Maximum power point tracking (|MPPT) power optimizers, a DC-to-DC converter
technology developed to maximize the power harvest from solar photovoltaic systems by
compensating for shading effects, wherein a shadow falling on a section of a module causes the
electrical output of one or more strings of cells in the module to fall to near zero, but not having
the output of the entire module fall to zero.
• Solar performance monitors for data and fault detection

WORKING:-
The solar panel system is a photovoltaic system that uses solar energy to produce electricity. A typical
solar panel system consists of four main components: solar panels, an inverter, an AC breaker panel, and
a net meter.
Solar panels are a fundamental part of the system. They have the ability to absorb light and transform it
into electricity. When solar energy, or sunlight, falls on panels, the material of solar panels absorbs it and
produces direct current (DC).
This direct current (DC) produced from the panels is unsteady and fluctuating. We cannot directly feed
this DC to home appliances. If you know, the electricity we receive from electrical grids is always
alternating current (AC). So, we need to convert DC produced from panels to AC. It is where the inverter
comes in.
An inverter is an electrical device that converts DC to AC. A solar inverter converts variant DC to AC.
The outgoing AC from the inverter is healthy electricity, which flows to the AC breaker panel of the
home.
The main AC breaker panel is the distribution board of the home. From here, the electric current gets
distributed to various circuits.
On bright sunny days, your solar panels will likely produce more electricity than you can consume. This
surplus electricity is exported to the utility grid via the net meter. The net meter records the amount of
energy exported by your solar system as well as the energy consumed from the grid. This energy export
adds to your energy credit.
Step-by-step working of the solar panel system
We can summarize the working of solar panels into the following points:

1. Solar panels absorb sunlight to produce electrical energy.

2. The inverter converts the absorbed energy into useful electricity.

3. The generated electricity is supplied to the AC breaker panel of the home.

4. And surplus electricity flows to the utility grid via the net meter.

Solar Power Is Renewable

Solar еnеrgy іѕ clean energy, a renewable еnеrgу ѕоurсе available anywhere in the world.
This mеаnѕ thаt wе cannot run оut оf ѕоlаr еnеrgу, аѕ opposed to nonrenewable еnеrgу sources (е.g.
fоѕѕіl fuеlѕ, соаl аnd nuсlеаr).
Wе wіll have ассеѕѕ to ѕоlаr energy for as long аѕ thе ѕun іѕ alive – another 6.5 bіllіоn уеаrѕ ассоrdіng
to NASA.
Wе hаvе wоrѕе thіngѕ to worry аbоut.
In fасt, scientists have estimated that thе Sun itself wіll swallow Eаrth 5 bіllіоn уеаrѕ frоm now.

Solar Power Is Abundаnt

The роtеntіаl оf ѕоlаr еnеrgу and solar systems we use іѕ bеуоnd imagination.
The ѕurfасе оf thе earth rесеіvеѕ 120,000 tеrаwаttѕ of solar radiation (ѕunlіght) – 20,000 tіmеѕ mоrе
роwеr than what is nееdеd tо ѕuррlу thе еntіrе wоrld.
So, with greenhouse gas emissions and the definite depletion of fossil fuels, we will have to rely on solar
power systems.

Solar Power Is Sustainable

An аbundаnt аnd renewable energy ѕоurсе is аlѕо sustainable, so our future lies in solar energy
systems.
Suѕtаіnаblе energy sources mееt thе nееdѕ of thе рrеѕеnt wіthоut соmрrоmіѕіng the ability оf future
gеnеrаtіоnѕ to mееt thеіr needs.
In оthеr wоrdѕ, solar еnеrgу іѕ ѕuѕtаіnаblе because there іѕ no wау wе can ever оvеrсоnѕumе it and stay
without it.
Solar Energy Systems Rеduсе Carbon Emissions
Sоlаr power is a сlеаn, renewable ѕоurсе оf еnеrgу thаt саn rеduсе carbon dіоxіdе еmіѕѕіоnѕ and
lower оur іmрасt on the nаturаl еnvіrоnmеnt.
Unlіkе trаdіtіоnаl fоѕѕіl fuеlѕ such as соаl аnd оіl, solar еnеrgу dоеѕ create pollutants (such as саrbоn
dioxide) and release them іntо the аtmоѕрhеrе аnd wаtеr ѕuррlу.
Evеn соmраrеd to nuсlеаr еnеrgу, a solar panel system is a mоrе environmentally frіеndlу ѕоlutіоn.
Pеrhарѕ thе most admirable аdvаntаgе оf ѕоlаr роwеr іѕ the fасt that іt bеnеfіtѕ our environment while
ѕіmultаnеоuѕlу helping our соuntrу to mаkе the necessary transition frоm fossil fuеlѕ.
In рurѕuіng еnеrgу ѕоlutіоnѕ tо hеlр the US rеduсе оvеrаll еmіѕѕіоnѕ, оur nation іѕ аlѕо еѕtаblіѕhіng
independence from fossil fuеls producers аbrоаd.
Aѕ thе wоrld searches fоr thе mоѕt cost-effective wауѕ tо rеduсе carbon dioxide output and air pollution.
In thе face оf glоbаl сlіmаtе сhаngе, solar еnеrgу has bесоmе a trеndу rеѕоurсе for a good reason.
Overall, solar power systems provide the best renewable energy that we can use to generate electricity
and reduce our energy bills while preserving the environment and eliminating our dependence on fossil
fuels.

8. RELAY
A relay is an electrically operated switch. It consists of a set of input terminals for a single or multiple
control signals, and a set of operating contact terminals. The switch may have any number of contacts in
multiple contact forms, such as make contacts, break contacts, or combinations thereof.
Relays are used where it is necessary to control a circuit by an independent low-power signal, or where
several circuits must be controlled by one signal. Relays were first used in longdistance telegraph circuits
as signal repeaters: they refresh the signal coming in from one circuit by transmitting it on another circuit.
Relays were used extensively in telephone exchanges and early computers to perform logical operations.
The traditional form of a relay uses an electromagnet to close or open the contacts, but relays using other
operating principles have also been invented, such as in solid-state relays which use semiconductor
properties for control without relying on moving parts. Relays with calibrated operating characteristics
and sometimes multiple operating coils are used to protect electrical circuits from overload or faults; in
modern electric power systems these functions are performed by digital instruments still called protective
relays.
Latching relays require only a single pulse of control power to operate the switch persistently. Another
pulse applied to a second set of control terminals, or a pulse with opposite polarity, resets the switch,
while repeated pulses of the same kind have no effects. Magnetic latching relays are useful in applications
when interrupted power should not affect the circuits that the relay is controlling.

TYPES OF RELAY:-

➢ Coaxial relay

➢ Contactor

➢ Force-guided contacts relay

➢ Latching relay

➢ Machine tool relay

➢ Mercury relay

➢ Mercury-watted relay

➢ Multi-voltage relay

➢ Overload protection relay

➢ Polarized relay

➢ Reed relay

➢ Safety relay
 ➢ Solid-state contactor

➢ Solid-state relay

➢ Static relay Ø Time-delay

➢ Vacuum relay

WORKING

➢ Relay works on the principle of electromagnetic induction.

➢ When the electromagnet is applied with some current, it induces a magnetic field around it.

➢ A switch is used to apply DC current to the load.

➢ In the relay, copper coil and the iron core acts as electromagnet.

➢ When the coil is applied with DC current, it starts attracting the contact. This is called
energizing of coil.

➢ When the supply is removed it retrieves back to the original position. This is called De
energizing of relay.

9. WIRES:-
A wire is a flexible strand of metal.
Wire is commonly formed by drawing the metal through a hole in a die or draw plate. Wire gauges come
in various standard sizes, as expressed in terms of a gauge number or cross-sectional area.
Wires are used to bear mechanical loads, often in the form of wire rope. In electricity and
telecommunications signals, a "wire" can refer to an electrical cable, which can contain a "solid core" of
a single wire or separate strands in stranded or braided forms.
Usually cylindrical in geometry, wire can also be made in square, hexagonal, flattened rectangular, or
other cross-sections, either for decorative purposes, or for technical purposes such as high efficiency
voice coils in loudspeakers. Edge-wound coil springs, such as the Slinky toy, are made of special flattened
wire.
Solid:-
Solid wire, also called solid-core or single-strand wire, consists of one piece of metal wire. Solid wire is
useful for wiring breadboards. Solid wire is cheaper to manufacture than stranded wire and is used where
there is little need for flexibility in the wire. Solid wire also provides mechanical ruggedness; and,
because it has relatively less surface area which is exposed to attack by corrosives, protection against the
environment.
Stranded:-
Stranded wire is composed of a number of small wires bundled or wrapped together to form a larger
conductor. Stranded wire is more flexible than solid wire of the same total cross-sectional area. Stranded
wire is used when higher resistance to metal fatigue is required. Such situations include connections
between circuit boards in multi-printed circuit-board devices, where the rigidity of solid wire would
produce too much stress as a result of movement during assembly or servicing; A.C. line cords for
appliances; musical instrument cables; computer mouse cables; welding electrode cables; control cables
connecting moving machine parts; mining machine cables; trailing machine cables; and numerous others.
At high frequencies, current travels near the surface of the wire because of the skin effect, resulting in
increased power loss in the wire. Stranded wire might seem to reduce this effect, since the total surface
area of the strands is greater than the surface area of the equivalent solid wire, but ordinary stranded wire
does not reduce the skin effect because all the strands are short-circuited together and behave as a single
conductor. A stranded wire will have higher resistance than a solid wire of the same diameter because
the cross-section of the stranded wire is not all copper; there are unavoidable gaps between the strands
(this is the circle packing problem for circles within a circle). A stranded wire with the same cross-section
of conductor as a solid wire is said to have the same equivalent gauge and is always a larger diameter.
However, for many high-frequency applications, proximity effect is more severe than skin effect, and in
some limited cases, simple stranded wire can reduce proximity effect. For better performance at high
frequencies, litz wire, which has the individual strands insulated and twisted in special patterns, may be
used.
The more individual wire strands in a wire bundle, the more flexible, kink-resistant, break-resistant, and
stronger the wire becomes. However, more strands increases manufacturing complexity and cost.
For geometrical reasons, the lowest number of strands usually seen is 7: one in the middle, with 6
surrounding it in close contact. The next level up is 19, which is another layer of 12 strands on top of the
7. After that the number varies, but 37 and 49 are common, then in the 70 to 100 range (the number is no
longer exact). Larger numbers than that are typically found only in very large cables. For application
where the wire moves, 19 is the lowest that should be used (7 should only be used in applications where
the wire is placed and then does not move), and 49 is much better. For applications with constant repeated
movement, such as assembly robots and headphone wires, 70 to 100 is mandatory. For applications that
need even more flexibility, even more strands are used (welding cables are the usual example, but also
any application that needs to move wire in tight areas). One example is a 2/0 wire made from 5,292
strands of No. 36 gauge wire. The strands are organized by first creating a bundle of 7 strands. Then 7 of
these bundles are put together into super bundles. Finally 108 super bundles are used to make the final
cable. Each group of wires is wound in a helix so that when the wire is flexed, the part of a bundle that
is stretched moves around the helix to a part that is compressed to allow the wire to have less stress.
Prefused wire is stranded wire made up of strands that are heavily tinned, then fused together. Prefused
wire has many of the properties of solid wire, except it is less likely to break.
Braided:-
A braided wire consists of a number of small strands of wire braided together. Braided wires do not break
easily when flexed. Braided wires are often suitable as an electromagnetic shield in noise-reduction
cables.

10. 16 Χ 2 LCD DISPLY

11. 100R RESISTOR Χ 3
12. 4.7K RESISTOR
13. 1K RESISTOR
14. RED LED LIGHT
15. GREEN LED LIGHT
16. BATTERY CLIP
CIRCUIT DIAGRAM:-

WORKING:- This device sense the fire with the help of flame sensor. It sends the input signal to the
microcontroller however which is read by microcontroller according to programming and sends the
output signal to DISPLAY, LED’S, and BUZZER, due to which we get a sound signal (alarm).