Rain Alaram Project

8/12/2019 Rain Alaram Project

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RAIN ALARM PROJECT

A rain sensor or rain switch is a switching device activated by rainfall

There are two !ain a""lications for rain sensors The first is a water

conservation device connected to an a#to!atic irrigation syste! that

ca#ses the syste! to sh#t down in the event of rainfall The second is a

device #sed to "rotect the interior of an a#to!obile fro! rain and to

s#""ort the a#to!atic !ode of windscreen wi"ers An additional

a""lication in "rofessional satellite co!!#nications antennas is to trigger

a rain blower on the a"ert#re of the antenna feed$ to re!ove water

dro"lets fro! the !ylarcover that %ee"s "ress#ri&ed and dry air inside

the wave'g#ides

Irrigation sensors

Rain sensors for irrigation syste!s are available in both wireless and

hard'wired versions$ !ost e!"loying hygrosco"ic dis%s that swell in the

"resence of rain and shrin% bac% down again as they dry o#t ( an

electrical switch is in t#rn de"ressed or released by the hygrosco"ic dis%

stac%$ and the rate of drying is ty"ically ad)#sted by controlling the

ventilation reaching the stac% *owever$ so!e electrical ty"e sensors are

also !ar%eted that #se ti""ing b#c%et or cond#ctance ty"e "robes to
http://en.wikipedia.org/wiki/Water_conservationhttp://en.wikipedia.org/wiki/Water_conservationhttp://en.wikipedia.org/wiki/Irrigationhttp://en.wikipedia.org/wiki/Windscreen_wipershttp://en.wikipedia.org/wiki/BoPEThttp://en.wikipedia.org/wiki/Irrigationhttp://en.wikipedia.org/wiki/Windscreen_wipershttp://en.wikipedia.org/wiki/BoPEThttp://en.wikipedia.org/wiki/Water_conservationhttp://en.wikipedia.org/wiki/Water_conservation


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!eas#re rainfall +ireless and wired versions both #se si!ilar

!echanis!s to te!"orarily s#s"end watering by the irrigation controller

( s"ecifically they are connected to the irrigation controller,s sensor

ter!inals$ or are installed in series with the solenoid valve co!!on circ#it

s#ch that they "revent the o"ening of any valves when rain has been

sensed

-o!e irrigation rain sensors also contain a free&e sensor to %ee" the

syste! fro! o"erating in free&ing te!"erat#res Ty"ically free&e sensors

are e!"loyed in regions where irrigation syste!s are not .blown'o#t. for

the winter *owever$ in areas where there is occasionally a chance of

overnight frosts$ s#ch as /lorida$ New Jersey$ Minnesota$ and

Connectic#t new lawn s"rin%ler syste!s are re0#ired to #se a rain

sensor

A new trend in .s!art. sensors 1li%e the 2irt#al Rain -ensor3 are #sing

recent weather observation data 1rainfall$ s#nlight$ te!"erat#re$ h#!idity$

and "ress#re3 to calc#late eva"otrans"iration of water 4sed in

con)#nction with forecast rain and te!"erat#res data these can direct

ho!e a#to!ationhardware at variable intervals and d#rations to o"ti!i&e

water savings

+ater is basic need in every one5s life -aving and "ro"er #sage of water
http://en.wikipedia.org/wiki/Floridahttp://en.wikipedia.org/wiki/New_Jerseyhttp://en.wikipedia.org/wiki/Minnesotahttp://en.wikipedia.org/wiki/Connecticuthttp://www.virtualrainsensor.com/http://en.wikipedia.org/wiki/Evapotranspirationhttp://en.wikipedia.org/wiki/Home_automationhttp://en.wikipedia.org/wiki/Floridahttp://en.wikipedia.org/wiki/New_Jerseyhttp://en.wikipedia.org/wiki/Minnesotahttp://en.wikipedia.org/wiki/Connecticuthttp://www.virtualrainsensor.com/http://en.wikipedia.org/wiki/Evapotranspirationhttp://en.wikipedia.org/wiki/Home_automation


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is very i!"ortant

*ere is an easy "ro)ect which will give the alar! when there is rain$ so

that we can !a%e so!e actions and save the rain water As a res#lt$ we

can increase the water levels of #ndergro#nd water by #sing #nderwater

recharge techni0#e Rain water detector will detect the rain and !a%e an

alert6 rain water detector is #sed in the irrigation field$ ho!e a#to!ation$

co!!#nication$ a#to!obiles etc *ere is the si!"le and reliable circ#it of

rain water detector which can be constr#cted at low cost

Rain Alarm Project Block Diagram:

Rain water sensor is the !ain co!"onent in the circ#it /or this rain

sensor$ no need to go and b#y in the !ar%et or online +e can do it

o#rselves )#st by ta%ing the "iece of 7a%elite or !ica board and


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al#!in#! wire 7a%elite or !ica board sho#ld be !ade co!"letely flat

and al#!in#! wire sho#ld be "asted on the flat board as shown in the

fig#re below of rain water sensor Care sho#ld be ta%en that there sho#ld

be no s"aces between the wire and board +hen the rain water sensor is

co!"leted$ it sho#ld get connected to the circ#it and voltage sho#ld be

"assed thro#gh the wires

Rain water sensor diagra! is shown below8

If there is no rain$ the

resistance between the wires will be very high and there will be no

cond#ction between the wires in the sensor If there is rain$ the water

dro"s will fall on the rain sensor which will also decrease the

resistancebetween the wires and wires on the sensor board will cond#ct

and trigger the NE999 ti!er thro#gh the transistors circ#itry Once NE999

is triggered$ it will !a%e the o#t"#t "in high and which will !a%e the

b#&&er to !a%e alar!


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Rain Alarm Project Circuit Diagram:

Rain water detector alar! circ#it is shown below


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Circ#it E:"lanation8

The "oints A and 7 of the circ#it are connected to the "oints A and 7

of the rain sensor res"ectively +hen rain is falling$ the rain water will

fall on the rain sensor which has al#!in#! wires on !ica or 7a%elite

sheet ;#e to the water on sensor$ the al#!in#! wire

will be shorted and !a%e

the transistor =@ to be t#rned ON C> will get charged by the resistor

R The reset "in of 999ti!er which is connected to the e!itter of =@

will be !ade "ositive when =@ reaches to the sat#ration !ode

The 999 ti!er is config#red in astable !ode +hen the reset "in of

the 999 ti!er is !ade "ositive beca#se of sat#ration !ode of =@$ it


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will generate the "#lse at the "in @ and !a%e s"ea%er to ring alar!

Ca"acitor is connected in between the "in @ of 999 ti!er and

s"ea%er beca#se to bloc% the ;C signal and allow only the variations

in the signal which !a%e the s"ea%er to !a%e so#nd The diode ;?

will not allow any reverse c#rrent fro! the ti!er

7eca#se of the resistor R and ca"acitor C>$ =@ will get in c#t'off

after so!eti!e and !a%e the reset "in of 999ti!er in negative and

s"ea%er will sto"s !a%ing so#nd The ti!e for 999ti!er to !a%e

s"ea%er so#nd de"ends on the val#es of C> and R

+hen there is no rain$ the al#!in#! wire of the sensor will not have

any resistance or cond#ction cannot trigger the circ#it

Note:

Rain senor sho#ld be %e"t in the o"en "lace at @B to B degrees fro!

the gro#nd As a res#lt$ rain water will not "resent on the sensor for

long ti!e


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This circ#it will a#to!atically switch of the alar! after so!eti!e and

LE; will glow contin#o#sly #ntil the rain sto"s

Applications of Rain Alarm Project:

1. In the irrigation$ it will detect the rain and i!!ediately alert the

far!er

2.

In a#to!obiles$ when the rain detector detects the rain it will

i!!ediately active the wi"ers and infor! to the driver

3. In co!!#nications$ it will boost the "ower of the antenna and

increase the signal strength to send or receive the signals

4. In nor!al ho#se hold$ with the hel" of rain water detector we can

a#to!atically save the rain water 1This can be done only when

ho!e a#to!ation is done and e0#i"!ent to save the rain water In

this$ rain water detector will detect the rain and hel"s to switch ON

the e0#i"!ent which will a#to!atically save rain water for different

"#r"oses3

5. This can also be #sed if there is a che!ical rain also This is very

co!!on in ind#strial areas


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+ater Level Alar! 4sing 999 Ti!er

*ow !any ti!es did yo#r overhead water tan% overflows d#e to yo#r

forgetf#lness It is a fre0#ent "roble! in all ho!es where "eo"le t#rn

ON the water "#!" and forget to t#rn it off when the water is filled This

"ro)ect is !ade to solve this "roble!

Important Post: Water Level Indicator Project

In this "ro)ect$ we are #sing a water level alar! #sing si!"le and low

cost hardware #sing a 999 ti!er circ#it The ai! of this "ro)ect is to

!a%e a water level detecting alar! with si!"le and low cost hardwarewitho#t co!"ro!ising on the "erfor!ance of the device

+ater Level Alar! 4sing 999 Ti!erCirc#it;iagra!8
http://www.electronicshub.org/water-level-indicator/http://www.electronicshub.org/water-level-indicator/


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The circ#it #ses a 999 ti!er in astable !ode with R>D??B oh!s$ R?D

>9B oh!s and C>D> #/ As we %now$ the fre0#ency of o"eration of theIC 999 in astable !ode de"ends on the val#es of R>$ R? and C> 7y

calc#lating the fre0#ency of the given astable circ#it$ we get the

fre0#ency to be aro#nd >>F*& The fre0#ency at which it o"erates is in

the a#dio fre0#ency

The >F Resistor R@ whose ends are connected to "in' and gro#nd

disables the circ#it by defa#lt and it enables when the water reaches its

f#ll level when the "robes get di""ed in water

The two "robes which are shown in the circ#it sho#ld be %e"t at the high

level for the water The astable !#ltivibrator in the circ#it is nor!ally

disabled and it gets enabled only when the "robes to#ch the water The

distance between the "robes sho#ld be less than a few centi!eters to

ens#re that the cond#ction between the "robes will ta%e "lace when

water is to#ched to these "robes +hen the water level rises to the

height of the "robes$ then the 999 circ#it will get enabled and the o#t"#t

of the 999 ti!er "rod#ces a s0#are wave o#t"#t with a fre0#ency of

abo#t >>Fh& This o#t"#t is given to the !ini lo#ds"ea%er which then

bee"s at an a#dio fre0#ency of >>F*&


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Intelligent 4na!big#o#s Night La!"-witcher+e #s#ally t#rn ON the lights in o#r ho#ses and offices !an#ally +e

need to t#rn ON the lights only when it is dar% -o$ how will that be if we

!a%e a circ#it which t#rns ON the lights a#to!atically when it is dar% In

this circ#it$ we shall see how to !a%e a circ#it which t#rns ON o#r

do!estic lights a#to!atically when it is dar%

+hile !a%ing a Night La!" -witcher$ there are !any as"ects which

needs to be ta%en into consideration witho#t which there is a "ossibility

of destroying the ho!e a""liances and lights In this circ#it$ strict

!eas#res are ta%en to ens#re that the lights to be o"erated are not

da!aged beca#se of switching In general$ if we !a%e a si!"le

a#to!atic night la!" switcher$ it !ay t#rn ON the lights when it is dar%

7#t here co!es a "roble! +hen the level of dar%ness is a""roaching$

the circ#it !ay get s#ccessive signals of dar% and light with little ti!e

intervals This !ay ca#se the circ#it to re"eatedly t#rn ON and O// the

lights at a high fre0#ency which can "ossibly da!age o#r lights within a

few !in#tes or ho#rs This ha""ens every ti!e at evening as well as in

the !orning when the light intensity crosses a val#e for which o#r circ#it

is sensitive and toggles the switch

In this circ#it$ it is not only a si!"le a#to!atic light switching circ#it$ b#t

also that it avoids re"eated fre0#ent switching of the devices which is

#s#ally ignored in !ost si!ilar circ#its b#t !ay have a detri!ental effect

on o#r o"erating devices In this case$ the lights This is why the circ#it is

na!ed as intelligent #na!big#o#s night la!" as it intelligently switches
http://www.electronicshub.org/auto-night-lamp-using-high-power-led/http://www.electronicshub.org/auto-night-lamp-using-high-power-led/


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the lights by avoiding re"eated switching ca#sed by #na!big#ity

+e #s#ally t#rn ON the lights in o#r ho#ses and offices !an#ally +e

need to t#rn ON the lights only when it is dar% -o$ how will that be if we!a%e a circ#it which t#rns ON the lights a#to!atically when it is dar% In

this circ#it$ we shall see how to !a%e a circ#it which t#rns ON o#r

do!estic lights a#to!atically when it is dar%

Circ#it ;iagra! for 4na!big#o#s Night La!"

-witcher8


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The o"eration of the circ#it is as follows8

The circ#it has two "hoto sensing devices which detect two levels of

intensities Light ;e"endant Resistors are #sed as "hotosensitive

devices in this circ#it The light de"endent resistor #sed with an o"'a!"

as co!"arator detects the level of light intensity The 4> IC G>

"rod#ces an o#t"#t which is the first light intensity and the 4? ICG>

detects the second light intensity These two light intensities are #sed to


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calc#late when the lights sho#ld be On and when they sho#ld be Off

witho#t "rod#cing #na!big#o#s signals

The two light detecting !od#les are arranged in s#ch a way that when

the first light intensity 1dar% "oint >3 is detected$ the circ#it t#rns On the

relay and hence the lights will t#rn On The circ#it will t#rn Off the relay

bac% again when both the light detecting !od#les detect light This

!a%es it eli!inate a!big#ities There !ay be si!"ler circ#its which

detect dar%ness and t#rn On the lights b#t !ost of the! fail to eli!inate

#ndesired re"etitive switching This circ#it does a wonderf#l )ob by

eli!inating #ndesired switching effects

The 999 IC 4@ is in the bistable !ode whereas the IC 4 acts as a

b#ffer The o#t"#t of first IC G> is given to the reset "in of the bistable

IC whereas the o#t"#t of second light detecting !od#le with IC G> is

given to the set in"#t of the bistable !#ltivibrator


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7attery Powered Portable Light

Power c#ts are 0#ite co!!on in develo"ing co#ntries Power c#t at night

ti!e is so!eti!es serio#s when yo# need a light for so!ething and yo#

cannot leave that wor% in the !iddle /or e:a!"le$ if yo# are ta%ing bath

or if yo# are reading for yo#r e:a! which is only one day ahead or if yo#

are in the !iddle of yo#r coo%ing$ whatever the sit#ation is$ !any ti!es it

is 0#ite disg#sting to face "ower c#ts at night +e will #nderstand the

i!"ortance of light when we have "ower c#ts In this article$ we shall

disc#ss a circ#it which can handle #ne:"ected and #ndesired dar%ness

in o#r ho!es or offices

The instant sol#tion to the "roble! described is to have a handy battery

"owered "ortable light which we can easily carry to the "lace it is

needed It "rovides considerable a!o#nt of brightness re0#ired to do o#r

daily tas%s


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Circ#it ;iagra! for 7attery Powered PortableLight8


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The circ#it !a%es #se of an IC 999 ti!er in astable !ode with a slightly

different config#ration which differs it fro! the standard !odel and also it

!a%es #se of a few "assive storage ele!ents li%e ind#ctors in order to

achieve high voltages than the s#""ly voltage so that !any LE;s can be

"owered with a low voltage battery The LE;s are connected in series

instead of "arallel to !a%e s#re that the circ#it r#ns on less "ower The

voltage is being !#lti"lied in order to satisfy the h#nger of all o#r series

resistors This %ind of circ#it re0#ires less "ower co!"ared to the

conventional resistor in series with LE;s "ower s#""ly ta%ing e0#al


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intensities into consideration

The circ#it !a%es #se of IC G999 instead of a conventional 999 IC The

reason behind that is the IC G999 ta%es lesser "ower than the

conventional ty"e IC G999 is !ade #sing CMO- technology whereas

the NE999 is !ade #sing TTL logic fa!ily This !eans that G999 is 0#ite

slower co!"ared to TTL based 999 IC b#t at the sa!e ti!e$ it cons#!es

very little "ower co!"aratively +e are o"erating the circ#it at a not so

high fre0#ency so that the G999 IC is 0#ite s#fficient for o#r s"eed

re0#ire!ents The circ#it also #ses a ?NGBBB MO-/ET which switches

on and off in sync with the IC 999 ti!er The ind#ctor which is "resent in

the circ#it stores the energy in its !agnetic fields and it hel"s #s to

o"erate the LE;s in series by "roviding a higher voltage than the so#rce

generates

Rain Alaram Project

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Transcript of Rain Alaram Project