Dell Edge Gateway 3003 Installation and Operation Manual

Sensors

The sensors on the Edge Gateway provide measurements on pressure, relative humidity and temperature, and motion.

Table 1. Sensor typesProvides the sensor types of your Edge Gateway.
Relative humidity and temperature sensor	ST Micro HTS221
Motion sensor—Accelerometer	ST Micro LNG2DMTR
Pressure sensor	ST Micro LPS22HB

Retrieve the raw data from the sensors by running the following commands. Then, apply the formula in the table to convert the data collected into measurements such as relative humidity and temperature.

Retrieving raw data from sensors

To query sensor devices, run the command.
```
$ cat /sys/bus/iio/devices/iio:device*/name
```
hts221 <-- device0, Humidity and temp.
lng2dm_accel <-- device1, G-sensor
lps22hb <-- device2, Pressure

To retrieve data from the humidity and temperature sensor, run the command.

$ cat in_humidityrelative_offset
$ cat in_humidityrelative_raw
$ cat in_humidityrelative_scale
$ cat in_temp_offset
$ cat in_temp_raw
$ cat in_temp_scale

To retrieve data from the motion sensor, run the command.

$ cat in_accel_scale_available
$ cat in_accel_*_scale
$ cat in_accel_*_raw

To retrieve data from the pressure sensor, run the command.
```
$ cat in_pressure_raw
$ cat in_pressure_scale
```

Converting raw data for use

Apply the formula in the table to convert the raw data collected into usable measurements.

Table 2. Convert relative humidity and temperature sensor raw dataProvides the formula for calculating data for relative humidity and temperature.
Relative humidity and temperature sensor	ST Micro HTS221
RH (in %) = (in_humidityrelative_raw + in_humidityrelative_offset) * in_humidityrelative_scale Temperature (degC) = (in_temp_raw + in_temp_offset) * in_temp_scale

Table 3. Convert motion sensor raw dataProvides the formula for calculating data for the motion sensor.
Motion sensor—Accelerometer	ST Micro LNG2DMTR
accel_{x/y/z} (m/s^2) = in_accel_{x/y/z}_raw * in_accel_{x/y/z}_scale

Table 4. Convert pressure sensor raw dataProvides the formula for calculating data for the pressure sensor.
Pressure sensor	ST Micro LPS22HB
Pressure (hPa) = in_pressure_raw * in_pressure_scale * 10 Temperature (m degC) = in_temp_raw * in_temp_scale