Water is basic need in
every one’s life. Saving and proper usage of water is very important. Here is
an easy project which will give the alarm when there is rain, so that we can
make some actions and save the rain water. As a result, we can increase the
water levels of underground water by using underwater recharge technique. Rain
water detector will detect the rain and make an alert; rain water detector is
used in the irrigation field, home automation, communication, automobiles etc. Here
is the simple and reliable circuit of rain water detector which can be
constructed at low cost.
Rain Alarm Project Block
Diagram:
Rain water sensor is the
main component in the circuit. For this rain sensor, no need to go and buy in
the market or online. We can do it ourselves just by taking the piece of
Bakelite or mica board and aluminum wire. Bakelite or mica board should be made
completely flat and aluminum wire should be pasted on the flat board as shown
in the figure below of rain water sensor. Care should be taken that there
should be no spaces between the wire and board. When the rain water sensor is
completed, it should get connected to the circuit and voltage should be passed
through the wires.
Rain water sensor
diagram is shown below:
If there is no rain, the
resistance between the wires will be very high and there will be no conduction
between the wires in the sensor. If there is rain, the water drops will fall on
the rain sensor which will also decrease the resistance between the wires and
wires on the sensor board will conduct and trigger the NE555 timer through the
transistors circuitry. Once NE555 is triggered, it will make the output
pin high and which will make the buzzer to make alarm.
Rain Alarm Project Circuit Diagram:
Rain water detector alarm circuit is shown below.
Circuit Explanation:
·
The points A and B of the circuit are connected to the points A
and B of the rain sensor respectively. When rain is falling, the rain water
will fall on the rain sensor which has aluminum wires on mica or Bakelite
sheet. Due to the water on sensor, the aluminum wire ‘w’ develops resistance
and gets conducted because of battery connector, the sensor and also to the
circuit.
·
When the aluminum wires are connected, the transistor Q1will get
turned on and make LED to glow and also Q2 will also be turned ON. When the Q2
is saturated, the capacitor C1 will be shorted and make the transistor Q3 to be
turned ON. C1 will get charged by the resistor R4. The reset pin of 555timer
which is connected to the emitter of Q3 will be made positive when Q3 reaches
to the saturation mode.
·
The 555 timer is configured in astable mode. When the reset pin
of the 555 timer is made positive because of saturation mode of Q3, it will
generate the pulse at the pin 3 and make speaker to ring alarm. Capacitor is
connected in between the pin 3 of 555 timer and speaker because to block the DC
signal and allow only the variations in the signal which make the speaker to
make sound. The diode D2 will not allow any reverse current from the timer.
·
Because of the resistor R4 and capacitor C1, Q3 will get in
cut-off after sometime and make the reset pin of 555timer in negative and
speaker will stops making sound. The time for 555timer to make speaker sound
depends on the values of C1 and R4.
·
When there is no rain, the aluminum wire of the sensor will not
have any resistance or conduction cannot trigger the circuit.
Note:
·
Rain senor should be kept in the open place at 30 to 40 degrees
from the ground. As a result, rain water will not present on the sensor for
long time.
·
This circuit will automatically switch of the alarm after
sometime and LED will glow continuously until the rain stops.
Rain Alarm Project Circuit Applications:
1.
In the irrigation, it will detect the rain and immediately alert
the farmer.
2.
In automobiles, when the rain detector detects the rain it will
immediately active the wipers and inform to the driver.
3.
In communications, it will boost the power of the antenna and
increase the signal strength to send or receive the signals.
4.
In normal house hold, with the help of rain water detector we
can automatically save the rain water. (This can be done only when home
automation is done and equipment to save the rain water. In this, rain water
detector will detect the rain and helps to switch ON the equipment which will
automatically save rain water for different purposes).
5.
This can also be used if there is a chemical rain also. This is
very common in industrial areas.
No comments:
Post a Comment