Is this the correct way to calculate for thermocouples?
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The ambient temperature at the site is 10 degrees, while it is 20 degrees in the control room. The voltage measured at the site is 4.3 mv; should the compensation temperature be calculated based on that of the control room? Is the final result 124 degrees?
You need to check what the calibration value of the thermocouple is; if you use a compensation wire, then you don’t need to worry about this
In principle, by using a compensation wire, the cold end of the thermocouple is moved from the field location to the end of the compensation wire; the final measurement result is therefore the temperature corresponding to the mV value plus the temperature of the cold end. Modern DCS systems perform automatic compensation.
What I mean is, during on-site inspections, after measuring the voltage at the site with a multimeter, should the control room temperature or the ambient temperature at the site be used in the calculations?
The key is to determine where the end of the compensation wire (or the compensation device) is located; if it is in the control room, then the temperature of the control room should be taken into account.
On-site, the entire premise was designed and constructed correctly
Why did the person ahead say to adjust the control room temperature
Should it be the control room temperature or the ambient temperature?
The temperature value corresponding to the mV value measured at the end of the compensation wire, plus the room temperature at that end position. I was busy with other things just now and didn’t notice that you were measuring the voltage in millivolts on-site. Sorry!
The mV value measured at the end of the compensation wire + the room temperature at the location of that end. I was busy with other things and didn’t notice that it was the mV value measured on-site; my apologies! Replies on mobile need to be approved; please reply again using a computer.