Barometric Pressure Sensor FAQs
Apogee SB-100 barometric pressure sensors are not factory calibrated but come with a generic calibration. The sensors drift less than 1 % per year. If a new calibration is required a custom calibration can be derived by plotting pressure measurements from a reference barometric pressure sensor versus the measured voltage output from an SB-100, then fitting a linear equation to the data. The slope of the linear equation is the calibration factor and the intercept is the offset.
The output range is 0 to 5 V, which corresponds to 15 to 115 kPa.
20 ms
Black is the signal. It connects to a single-ended channel.
Green is the ground for signal output. It connects to an analog ground.
Red is the power input. It connects to 5 V.
SB-100 barometric pressure sensors are designed to be mounted inside the datalogger enclosure, where they are protected from the elements, specifically precipitation, condensation, and dynamic pressure caused by wind. The datalogger enclosure should not be air tight, as the pressure sensor must be exposed to an environment where the pressure varies with ambient pressure. As a result, vent holes in the enclosure are required and should be in the bottom of the enclosure to minimize the impact of dynamic pressure caused by wind.
A quick and easy check of sensor functionality can be determined using a DC power supply and a voltmeter. Power the sensor with 5 V DC by connecting the positive voltage signal to the red wire from the sensor and the negative to the green wire from the sensor. Use the voltmeter to measure across the black wire (output signal) and green wire. The sensor should read approximately 4100 mV at sea level, with the voltage output decreasing by approximately 50 mV per 100 meters above sea level.
A compatible measurement device should have resolution of at least 0.459 mV (0.01 kPa). Compatible measurement device should also have a full scale range spanning the sensor signal output range or 100 to 480 mV.
Yes, if properly spliced, the signal from the sensor is not affected by splicing on additional cable. Please check the product manual for details and limitations on adding cable. For information on how to create a proper waterproof splice, please visit our instructional webpage or watch our video. Additionally, we offer custom cable lengths of our high quality cable at the time of purchase.