Respected sir,
I am using xtr105p (DIP package). The input to the same is PT 100 3 wire RTD, and the temp range is 0-150 degree Celsius. We are facing a problem with the IC's lead resistance compensation for 3 wire PT100 RTD.
With no lead resistance i get a proper output as follows:
for 0 degree = 4mA
for 150 degree=20mA
But when a "LEAD RESISTANCE" of "4.7ohms" is connected it gives me following error in output:
for 0 degree = 6.64mA
for 150 degree=22.45mA
In the datasheet it is mentioned that the xtr 105 provides the compensation for the lead wire resistance. The circuit diagram borrowed from the datasheet is FIGURE No.3 on PAGE 10. We have verified the resistances of the 3 lead wires, they are as (4.78, 4.79, 4.95 ohms).
so why this problem is occurring and what can be the possible solution for the same?