Host Engineering Forum

General Category => General Discussion => Topic started by: Proto on June 27, 2022, 02:59:06 PM

Title: BX-04UT
Post by: Proto on June 27, 2022, 02:59:06 PM
Is there a way to read the resistance off the BX-04ut module?

How do you know that module is calculating the correct temperature? Is there a way to verify that the temperature is correct?

TIA
Title: Re: BX-04UT
Post by: BobO on June 27, 2022, 03:43:51 PM
Is there a way to read the resistance off the BX-04ut module?

How do you know that module is calculating the correct temperature? Is there a way to verify that the temperature is correct?

TIA

The module doesn't calculate it, the LTC2983 chip does. If you don't trust the interface chip to correctly calculate the value, you really can't trust the interface chip to return the resistance, which is also a calculation from a voltage generated by a small excitation current and precision sense resistor. The module returns failure flags if there is a problem with the sensor. The only way I can think to verify would be to add redundant sensors, possibly of a different type, and make sure both are within a reasonable range.
Title: Re: BX-04UT
Post by: RBPLC on June 27, 2022, 03:46:17 PM
Calibration is how you know the temperature is correct. In general you'll need a process calibrator or thermal well to provide a reference. In my experience, the UT modules can be 3-4 deg F from reference temperatures. This is pretty common for non-data acquisition/process control devices. For those modules, I typically use a filter time of about 3 seconds as well to reduce some of the noise.