How to Build a Soil Moisture Sensor Meter with Automatic Water Sprayer Circuit

The post points out a 10 stage soil moisture sensor meter circuit with an built-in automatic water sprayer mechanism for repairing the important situation of the soil.


Talking about the presented schematic we observe a basic yet seriously precise soil moisture sensor meter with an automatic predetermined water shower system for rebuilding the soil moisture stage to optimum points.
The design is dependent on a single voltage sensor/LED driver IC LM3914 or a LM3915. The demonstrated sensor pins that happen to be essentially two brass rods are set up as voltage sensors across the essential soil area where it might be positioned.
The voltage across these pins rely upon the level of moisture display across that specific soil area. This felt voltage proportionate to the soil moisture level is used across pin5 of the IC for the needed comparison with an integrated reference voltage level.
The threshold level exactly where the shower pump ought to be turned on is placed by P1. Based upon this setting, the IC internal circuitry experiences the soil moisture and creates a shifting sequential low logic across the presented 10 outputs beginning with pin1 to pin10. This felt output across the appropriate IC outputs are mentioned by 10 specific LEDs which illuminate in sequence as a reaction to the rising or depleting soil moisture levels.
The LED illumination sequencing style might be chosen to imitate a bar mode or a dot mode by adequately placement the pin9 switch of the IC to both ON or OFF.
The phase consisting BC547 and BC557 make up the relay driver phase for managing the motor pump switching as per the user choice.
The base of the PNP transistor is properly incorporated with any of the output pins of the IC relying at exactly what moisture threshold the user desires the motor to be began or stopped.
For instance guess pin15 establishes a specific moisture threshold level of the soil and the user senses it to be the unsafe level at which the motor ought to be began to be able to bring back the soil moisture, then this pinout could possibly be selected and connected with the base of the BC557 transistor for the mentioned motor switching.
Once the motor is activated the soil is showered until its moisture level is renewed to the preferred level and this encourages the IC to revert its sequence from pin15 to pin14 and toward pin10, switching OFF the motor and the shower.
The above method continues repeating ensuring the soil moisture level by no means goes down below the unwanted parched situation.