This garden water alarm system will tell the garden owner regarding the precise moisture status of the garden soil through LED illumination and buzzer. It will indicate through an LED when the average condition of the soil is saturated with water, and will also indicate if the soil is almost dry by sounding an alarm buzzer.
Its quite common that plant growers using a significant ' collection' of plants need to perform really hard to be able to create effective results from the pants..
The watering of plants is merely a single work that needs be performed and can turn out to be time consuming if more and more plants are participating.
The above fact may not be correct for the ' domestic' plant where, on several events proper maintenance could be neglected and the mud could be allowed to run dry on occasions.
The automatic watering of plants in gardens is usually facilitated by electronics. Thus, the discussed easy circuit demonstrated in this article will certainly create an clear sign once the plant needs a water topping up.
How the Circuit Works
The two electrodes ( @ and © in the illustration) are placed in the pot and form the ' hydro switch'.
When water covers the ends of these probes the output of the 1 kHz oscillator (Nl) will be provided to level (C) in the circuit diagram.
The AC signal is actually solved by means of diodes D1 and D2 and result in pin 13 of N4 that must be taken low.
Since this gate forms the basis of another oscillator, a low level on this input minimizes it from carrying out its work.
As soon as the water level declines below the end of the © probe pin 13 will probably be rigged high by R9.
The N4 oscillator will now create an audible output on the buzzer showing the fact that plant needs water.
The buzzer tone can be varied by modification of the 500 k preset.
A third electrode @ is additionally positioned in the pot however finishing at a more impressive range than Q or ©, in fact it should just achieve the utmost water level point.
This certainly will provide you with a idea to its goal.
Switch S1 should be pressed while watering the plant.
Once the water level in the pot actually reaches the finish of electrode ®, LED D5 will light thus giving an exact image indication that the plant has enough water.
To economise on current consumption of the LED, it stays lit for a few ten seconds after SI is produced.
This time can be increased if needed by increasing the value ofC8.
How to Make the Electrodes
The electrodes can be produced from lengths of copper wire or etched as tracks on a strip of printed circuit board.
Since the current via them will probably be AC, corrosion will be lowered and they must have a fairly longevity.
The supply voltage is not really essential and could be ranging from 5 to 15 volts.
On the other hand, when it is significantly less than the recommended 9 volts, the cross section of electrode © will likely need to be relatively large to accommodate the voltage fall across DI…D3.