Background & Definitions
Calibration is defined as a comparison of a sensor measurement and a known standard, followed by a subsequent adjustment of the sensor measurement so that it measures accurately.
Calibration is important because reliable data and measurements are the basis of correct, well-informed decisions. It is simply a question of reliability and whether or not you can trust your own data to be accurate.
The level of uncertainty that is accepted, is very different from industry to industry. For instance, the measured level of oxygen inside a patients bloodstream at a hospital needs to be measured more accurate than the level of oxygen inside a beer fermentation tank. As a consequence, the time between calibration of equipment will vary.
The practical reason behind this, is that all sensor equipment will degrade over time. How quickly this happens for a sensor depends on many factors, such as:
- The harshness of the physical environment, the sensor is placed in (e.g. weather, corrosive gases, moisture)
- Has the sensor received any electrical shock lately?
- Has it received mechanical stress that is out of the specified limits provided by the manufacturer?
- Which type of sensor-instrument principle is used?
All these factors determine whether the sensor will degrade quickly or over a long period a time. Therefore, it is always a good idea to calibrate equipment if accurate measurements are needed.
That is why we have it easy for our customers to calibrate their Consibio enabled sensors through the user interface in Consibio Cloud.
How do I calibrate a sensor in Consibio Cloud?
If you want to calibrate a sensor in a Consibio Cloud project, you first have to identify the sensor element tile in that you want to calibrate. An example could be a temperature value that has the name “Temp. Inside nr. 4” or “RH section 11”.
When you have found the tile with that name, click the tile to open a so-called “drawer” that includes extra information on that specific sensor element.
Next up, you press the Calibrate Sensor button in order to open a second drawer. Here you will be presented by a screen where the calibration data can be inserted.
By click’ing the Add Point button, a small table to the right will appear with the “Point no.”, “Measured output” and “Expected value” columns inside. For the calibration curve calculation to start, you have to manually enter the measured output (i.e. what value did the sensor show you) at the time of measuring the calibration standard (i.e. the expected value).
You can add as many calibration points as you like – Consibio Cloud will automatically calculate the best linear fit to the data you enter, no matter the amount of calibration points.
Once your calibration points have been added, you should see the new Adjusted slope and offset values of the calibration curve before pressing the Confirm Calibration button.
And finally, you have calibrated your specific sensor in Consibio Cloud.
Hopefully, this gives you an idea of how to calibrate your sensor through the user interface in Consibio Cloud. If you have suggestions to improvements to the calibration feature, don’t hesitate to reach out to us at firstname.lastname@example.org.
I just noted the calibration values on a piece of paper in the field – Can I calibrate the sensor later, when I am at the office?
You can both calibrate onsite or save the calibration values and apply it later. However, we recommend always using the Consibio Cloud user-interface to run the calibration, as all calculations are done automatically. This way, you are sure that the calibration is done correctly.
Consibio Cloud calibration works just as fine on a mobile device, i.e. smartphone or tablet, and is easy to use even when you are onsite at the specific sensor location.