I am trying to use LabView for Data Acquisition using a combustion gas detection sensor. The sensor is in a Wheatstone circuit, so the output measured is the voltage change. At the same time, we have a temperature sensor on the same PCB board because change in temperature affects the sensitivity of the Gas Detection sensor. So we have to calibrate the sensor against the temperature sensor. My question would be, will I be able to do the calibration in LabView? If yes, how? And will I be able to do it i the base version of LabView? Thank you.

I do not think scaling in DAQmx will do what you are asking because the linear scaling depends ona fix "m" and fixed "b" as in; Conc. = m(Delta V) + b Those images show that both "m" and 'b" are a function of temperature. So start out simple and just write a VI that will let you enter a "delta V", a "m" and a "b". Get that to work first. Then take a look at a pair of functions on the array palette; Threshold 1d array and Interpolate 1d array Read the help on those and play with them until you figure out how to use them together. They will let you develop code that works as follows... 1) Search an array of temperatures (that you will enter based on those graphs) based on temperature value (your measured temp). It will return a factional index that represents where in the array of the temps you entered your measured temp would be found. 2) Use the fractional index to interpolate an array of "m"s that you enter based on the graph. Use the "interpolated "m" to drive that simple VI you started with. Repeat step #2 above but this time use an array of "b" values and use the interpolated "b" to drive that same sub-VI. If you code it right, enter the value from your graphs correctly (i.e. you should have one temp value for every "m" value and "b" value in your arrays) you should have a VI that scales the "Delta V" and adjusts for temperature. If you have trouble, post the code and someone should be able to give you a hint. Ben

Hi nmc, will I be able to do the calibration in LabView? If yes, how? At first you should draw your "calibration algorithm" on a sheet of paper. Yes, paper… Once you figured out how you can calibrate your sensor (do you have a datasheet, manual, whatever?) you can start to code that algorithm - that's the usual order of things… And will I be able to do it i the base version of LabView? Sure. Maybe you need to program some functions, which are only available in better LabVIEW packages, as subVIs - but all the usual math functions are available!

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Sensor and Temperature Calibration in LabView

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Thank you very much. I will learn to do this first!

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Sensor and Temperature Calibration in LabView

Re: Live Calibration to Another Reading