14-07-2014, 11:29 AM
INTELLIGENT AUTOMATIC PLANT IRRIGATION SYSTEM
INTELLIGENT AUTOMATIC.pptx (Size: 65.44 KB / Downloads: 19)
INTRODUCTION
Irrigation is the key to a successful garden. Long gone are the days of manual watering
or relying on a friend to water when you are on vocation or away on business. The project presented
here waters your plants regularly when you are out for vocation .the circuit comprises sensor parts
built using op-amp LM324. Op-amp is configured here as a comparator. Two stiff copper wires are
inserted in the soil to sense the weather the soil is wet or dry .The comparator monitors the sensor
and when sensor sense the dry condition then the project will switch on the motor and it will switch
off the motor when sensor is wet.the comparator does the above job it reciees the signals from the
sensors.
To arrange the circuit,insert copper wires in the soil to a depth of about 2cms,keeping them 3cms
apart. for small areas a small pump such as the one used in air coolersis able to pump enough water
with in 5 to 6 seconds.the timing components for the timer are selected accordingly. The timing can
be varied with the help of preset voltage .
The circuit is more effective indoors if one intends to use it for long periods. This
is because the water from reservoir(bucket, etc) evaporates rapidly if it is kept in the open. For
regulating the flow of water, either a tap can be used or one end of a rubber pipe can be blocked
using M-seal compound, with holes punctured along its length to water several plants
Circuit operation
When the soil dries out, the between the copper wires (sensor probes A and B) increases. If
the resistance increases beyond a preset limit, output pin 1 of op amp N1 goes low. This
triggers the timer IC2 (NE555) configured as a monostable multivibrator. As a result relay
RL1 is activated for preset time the water pump starts immediately to supply water to the
plants. As soon as the soil becomes sufficiently wet, the resistance between sensor probes
decreases rapidly. This causes pin 1 of op-amp N1 to go ‘high’. LED1 glows to indicate the
presence of adequate water in the soil . The threshold point at which the output of op-amp
N1 goes ‘low’ can be changed with the help of preset VR1
Conclusion
The circuit is more effective indoors if one intends to use it for long periods. This is because the
water from reservoir(bucket, etc) evaporates rapidly if it is kept in the open. For regulating the flow
of water, either a tap can be used or one end of a rubber pipe can be blocked using M-seal
compound, with holes punctured along its length to water several plants