Part 5: Can you use the circuit for a heating circuit? In a heating circuit, the heater turns on when the temperature gets too low. Adjust the circuit so it will work for heating. Note how you changed the circuit and show calculations below. Obtain a bag of ice or cool object and see if it works. Need to do the following: Adjust R1 so the set is BELOW room temperature (maybe 19ºC). Switch connections to Pin 13 and Pin 12. Now the LM35 should be connected to PIN 13 and V2 should be connected to PIN 12. Initially, room temperature (LM35) will be higher than the set Then the temperature of the LM35 goes below the set point it will turn on the circuit since the voltage to Pin 12 will be greater than Pin 13. Part 6: Can and be at different temperatures? “on” “off” Why you want and to be set at different temperatures? “on” “off” For the heating circuit, this will allow the heater to heat the room past the low set point. This will ensure that people are comfortable and decrease the number of heating cycles which may make the system more efficient. Continuing to use the heating circuit, complete the below. State Temperature (ºC) LM35 Voltage (V) On (lower 19 V2,L= 0.19 limit) Turns Off (upper limit) 21 V2,U= 0.21 The addition of one resistor (R4) will make different and “on” points “off” for this circuit.
Part 5: Can you use the circuit for a heating circuit? In a heating circuit, the heater turns on when the temperature gets too low. Adjust the circuit so it will work for heating. Note how you changed the circuit and show calculations below. Obtain a bag of ice or cool object and see if it works. Need to do the following: Adjust R1 so the set is BELOW room temperature (maybe 19ºC). Switch connections to Pin 13 and Pin 12. Now the LM35 should be connected to PIN 13 and V2 should be connected to PIN 12. Initially, room temperature (LM35) will be higher than the set Then the temperature of the LM35 goes below the set point it will turn on the circuit since the voltage to Pin 12 will be greater than Pin 13. Part 6: Can “on” and “off” be at different temperatures? Why you want “on” and “off” to be set at different temperatures? For the heating circuit, this will allow the heater to heat the room past the low set point. This will ensure that people are comfortable and decrease the number of heating cycles which may make the system more efficient. Continuing to use the heating circuit, complete the below. State Temperature (ºC) LM35 Voltage (V) On (lower limit) 19 V2,L= 0.19 Turns Off (upper limit) 21 V2,U= 0.21 The addition of one resistor (R4) will make different “on” and “off” points for this circuit.