So I have 8 pt100 RTD's that I need to measure the temperature of, and I know the resistance of the RTD changes as its temperature goes up therefore I would use the resistance to obtain the temperature. I currently have my wheatstone bridge set up and I have a 2.5 V source going into my wheatstone bridge. My setup currently is as shown in my uploaded circuit configuration with a balanced circuit having all the resistors at 100 ohms and the RTD being the only thing that has a change in resistance. Currently I get the correct voltage difference out when measuring across the resistors when my RTD changes resistance ( since it is hooked up to a heat pump).
The thing is that I have to get readings off of Labjack, a program that measures the voltage of the wires connected to it. In this case I am using a labjack U3, so if a wheatstone bridge where my RTD resistance is 115 Ohms, and the others are 120 ohms and a voltage source of 2.5 V my V_bridge would be .0872 V, and I get approximately that. I know I need a DIP in-amp for my breadboard, but I do not know what a good one to buy would be that could meet my specifications. Any good recommendations?
How do I get the labjack which displays the voltage of the circuit, in this case my voltage across my bridge to be a temperature? I have the file with the equation relating Resistance and temperature attached. One thing to note is that the labjack can not read voltages higher than 2.4 V so my V_output of the in-amp should not exceed that.
As far as dealing with negative temperatures, I may be dealing with some slightly negative temperatures but if it was truly negative then it would freeze the water flowing through the heat pump so I don't believe that is correct. That being said I think I'll just be dealing with temps greater than 0 degrees Celsius.
http://www.micropik.com/PDF/pt100.pdf This website also shows the relationship between resistance and temperature for this particular RTD.
Would appreciate any help! Thanks!
TLDR: Recommended DIP In-amp for a temperature sensor (pt100) with a voltage source of 2.5 V ? How do I obtain my temperature with my v_output using the equation in the z251 pdf file?
The thing is that I have to get readings off of Labjack, a program that measures the voltage of the wires connected to it. In this case I am using a labjack U3, so if a wheatstone bridge where my RTD resistance is 115 Ohms, and the others are 120 ohms and a voltage source of 2.5 V my V_bridge would be .0872 V, and I get approximately that. I know I need a DIP in-amp for my breadboard, but I do not know what a good one to buy would be that could meet my specifications. Any good recommendations?
How do I get the labjack which displays the voltage of the circuit, in this case my voltage across my bridge to be a temperature? I have the file with the equation relating Resistance and temperature attached. One thing to note is that the labjack can not read voltages higher than 2.4 V so my V_output of the in-amp should not exceed that.
As far as dealing with negative temperatures, I may be dealing with some slightly negative temperatures but if it was truly negative then it would freeze the water flowing through the heat pump so I don't believe that is correct. That being said I think I'll just be dealing with temps greater than 0 degrees Celsius.
http://www.micropik.com/PDF/pt100.pdf This website also shows the relationship between resistance and temperature for this particular RTD.
Would appreciate any help! Thanks!
TLDR: Recommended DIP In-amp for a temperature sensor (pt100) with a voltage source of 2.5 V ? How do I obtain my temperature with my v_output using the equation in the z251 pdf file?
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