provide the projects based on instrumentational amplifier
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Automatic temperature controlled fan
Here is a scheme through which the fan can be linearly thespeed controlledautomatically, dependingon the room temperature. The scheme is effective because it ishighly control thyristors forpower. Alternatively, samecircuit can be used to automatically control AC temperaturecontrolled.In this diagram, temperature NTC thermistor is sensorused, i.e. one Havinga multiplier negative temperatures. The resistance of the thermistor in Thevalue 25° with the isabout 1 kilogram-ohm.Op Amp A1 essentially works for ASI to V (current-voltage) converterand converts voltage fluctuations low variationsinto. For amplifythe voltage changes due to changes in the amplifierformed devices, intemperature OU A2, A3, and A4is is used. Resistor R2 and Zener diode diodeD1 combination is used to generatingreference voltage, how we want to amplifyonly voltage change due to temperature thechange.Op-Amp μA741 (IC2) works as a acomparator. One entry in the comparatoris out of instrumentationamplifier while another inputis left straightened andsuitably weakened AC voltage sample.This is a negative voltage pulsatingDC occurs. It should be noted, thatwith fever, contact 2 ofIC2 is increasingly negative positive pulse width andhence goingoutput (output 6) increases the temperature linearlywith. Thus IC2functions as pulse width modulatorin this pattern. Output of thecomparator is connected with the particles, which in turn controls the ACpower delivered fan (load).The scheme has a high sensitivity plot output voltage values (for throttle) canbe ranged from 120 to 230 v (for temp range from 22° C to 36° C), and therefore widevariations speed available. Alsonote that the speed of linear and notin steps varies. In addition, because the optical couplers, control scheme isused is isolatedfrom the power scheme, thus providing a addedsafety. Note that for any given temperaturethe fan speed (i.e. acrossload) voltage can be adjusted to the desired adjustment sliders valueby VR1 and VR2appropriately. Potmeter VR1 should it first be keptin in middle position to realize growth approximately40 from instrumentationamplifier. This can then be trimmedslightly get linear velocity change thefan.
Reference:
http://studentbank.in/report-automatic-t...z3IBAXcdyY