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AGROFARM WEATHER MONITOR USING Lab VIEW
INTRODUCTION
• Innovation in agriculture field
• Implementing instrumentation tech. in agricultural field
• The quantity and quality of various parameters in the agricultural farm affects the growth of plant and crop yield.
• Various parameters in a farm are temperature, atmospheric humidity, light intensity and soil moisture content.
• It is essential to monitor these parameters in the farm either it is a green farm or not.
• We concentrate in the farming of mushrooms, which needs extra care in its production.
SENSORS
• Temperature Sensor
• Light Sensor
• Humidity Sensor
• Soil Moisture Sensor
TEMPERATURE SENSOR
• RTD( Resistance Temperature Detector) is used to detect the temperature.
• Resistance of the material changes with the
changes in the temperature.
• RTD has a positive temperature coefficient.
• Linear range of operation in our application.
• Pt RTD of range -50◦C to 250◦C is used.
• The change in resistance can be converted into change in voltage through a Wheatstone bridge.
LIGHT SENSOR
• LDR( Light Dependent Resistor) is used to detect the intensity of light .
• Resistance of the material changes with the change in the intensity of light.
• The LDR who’s resistance decreases with increase in the intensity of falling light is used here.
• The change in resistance is converted to corresponding change in voltage through a Wheatstone bridge.
HUMIDITY SENSOR
• Water- vapor content of air is important parameter
• Hydroscopic salts like,LiCl2 exhibit changes in electrical properties [resistivity]with changes in humidity
• Humidity -moisture -1/(resistivity)
• Here humidity sensor module by VEGAROBOKIT is used
• SY-HS-220 series
FEATURES:
• Humidity sensor module with voltage output
• Wide temperature compensation range
• High reliability and long term stability
• Linear DC voltage output for humidity range
• High sensitivity and low hysteresis
• Compact size and cost effectiveness
SOIL MOISTURE SENSOR
• Our own method to determine the moisture content in the soil.
• A cheap sensor which effectively detects the
moisture content.
• Made of two stainless steel electrodes and a little quantity of Plaster of Paris.
• Plaster of Paris shows water adsorbing property.
• The amount of water content in the plaster of paris affects the conduction through the electrodes, thus there will be a change in resistance of the electrodes.
• This change in resistance is then converted to voltage output through a Wheatstone bridge
SIGNAL CONDITIONING
• Consists of a Wheatstone bridge and an instrumentation amplifier arrangement.
• Each sensor output is connected to corresponding Wheatstone bridges which are designed to suite for it.
• The output of Wheatstone bridge is amplified using instrumentation amplifiers.
• These outputs are then connected to DAQ.
• The power supply units made of ICs 7805,7815,7915.
• Contains rectifier, filter and regulator units
• Provides supply for bridge circuit and amplifier sections