Persistent precise: humidity sensor drift analysis
A humidity sensor how long should be calibrated?They drift amplitude is how much?This is our often asked two questions, in the absence of more information, these two questions hard to answer, because the environmental conditions when using the sensor has a great influence on its stability.
Here, we try to provide some ideas for you.
In the case of HMP110 humidity sensor,HMP110 both can be used as independent humidity and temperature transmitter, asHMT120 and HMT130 humidity transmitterMeasuring probe.Many customers are also fully believe we HMP110 probe calibration results to them.
We carefully analyzedHelsinki, Boston, Tokyo and Beijing four service centerThe test results of HMP110 calibration before.Although we have no information about the probe has been used for what purpose, but you can assume that most of the probe for monitoringClean roomorThe data centerThe environmental conditions.For these products, the request of application scenarios are usually not tough.We have 2000 independent HMP110 probe were analyzed about 5000 times the calibration, and on some of the probe calibration for many times.We assume that the probe during service life without any other adjustments, and the assumptions made since the last time the calibration, under the condition of 0% RH and 75% RH relative humidity RH error before the adjustment and the environment temperature of the measured values of figure:
Two years later, the main statistical information about the adjustment error of the former is as follows:
0% RH |
75% RH |
Temperature ° c. |
|
The average |
- 0.01% RH |
- 0.32% RH |
0.00 ° c. |
The standard deviation |
0.18% RH |
0.88% RH |
0.10 ° c. |
(Has moved to extreme outliers, leaving 170 samples.
In the case of statistic and analysis in-depth, our main conclusion is:
Even though most of the probe in the use of two years later, the specification is still like new (+ / - 1.5% RH / 0.1 ° C (the technical index of the product samples))
Calculated by the uncertainty of plus or minus 0.5% RH/year, plus or minus 0.02 ° C/year forecast drift seems reasonable
Learn more aboutHMP110More information on this humidity transmitter no maintenance, high accuracy and good stability.
