daviteq Lidar People Counter, Руководство пользователя

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The temperature of the circuit board, in oC.
The Daviteq G4 Gas Sensor must be connected to a reading device, normally it is a wireless transmitter like Sub-GHz,
Sigfox, or LoRaWAN.
In the reading device, the following parameter is configured in advanced:
For example, with an NH3 gas sensor, the default value of the Sensor current output is 110nA/ppm and R_gain = 100
Kohms.
Therefore, the default NH3 amplifier sensitivity = 11 mV/ppm
- The sensor current output of a sensor is different from the other sensor. It is not the same value for all sensors after
manufacturing.
- The sensor current output of a sensor will be changed over time. For example, the NH3 sensor current output will be
reduced by about 5% of the signal per six months in clean air at 25 oC temperature.
- The R_gain of the circuit also has a 0.1% or 0.05% tolerance;
Therefore, users need to calibrate the sensor before use or in a pre-defined interval time (6 or 12 months for example).
Instructions to attach the calibration cap onto the sensor module to get Zero or Span values.
3. Calibration of the Daviteq G4 Gas Sensor
amplifier sensitivity (mV/ppm): it is the voltage output of the amplifier circuit = Sensor current output
(nA/ppm) x R_gain
Depending on the sensor type and R_gain value, the sensor sensitivity must be calculated and pre-configured
into the reading device.
3.1 Why do we need to calibrate the gas sensor? There are some
reasons:
3.2 How to calibrate the G4 Gas sensor?