Rosemount temperature variation issue
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At around 104 degrees under operating conditions, the resistance measured on-site was also 140 ohms; it’s roughly 104 degrees. When a 475 device is connected with a current output of 9 mA, everything works normally, but when a multimeter is used, the current is only 2 mA. Why is that?
Is your multimeter connected correctly? What is the temperature range?
140 ohms, 104 degrees – what type of primary components are you using? If the multimeter’s wiring is correct, restore it to its factory settings. What temperature does the system display? If the display is correct, then it’s your operation that’s incorrect; if the display is wrong, then there’s a problem with the instrument itself
If it is confirmed that the operation is correct, use another multimeter that is known to be working properly to measure the current value again
Before measuring the current value, it is possible to check the accuracy of the multimeter, for example by using a signal generator