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Grove - temperature sensors, humidity and pressure

In the industrial automation and automated manufacturing processes are very commonly used sensors are temperature, humidity and pressure. Is not measured by size, as a rule, is converted to a voltage signal, which is received by the microcontroller contained in the measurement system. Such sensors are used in the automotive industry and in the construction of character hobbystycznym, which are ideal sensors of atmospheric parameters in the form of Grove modules that you can connect to Arduino.

Temperature sensors - different designs, one goal

The purpose of the measurements using the temperature sensors is to obtain information determining the degree of cooling or heating of the object of measurement. One of the most popular designs of sensors to measure temperature, sensors, produces a signal, which can be found in thermometers medical. The change in body temperature causes a change in the amount of current passing through the thermistor, whose resistance may also change. A thermistor is built of semiconducting materials is particularly sensitive to temperature changes. The resistance of the thermistor decreases with increasing temperature of the measurement object. In turn, the termoparowe sensors used to measure temperature, pipes made from two pieces of alloy metal. The design of the thermocouple sensor uses the principle of the Seebeck effect. The difference of the thermodynamic characteristics of the metals, in which the measuring alloy wires causes the creation of a strong difference of potentials, proportional temperature measurement. The use of thermocouples allows to achieve a wide measurement ranges. The sensor reads the thermocouple and the thermoelectric voltage which is its output signal. Temperature sensors infrared, infrared light, directed towards the measurement object and is reflected back to the sensor. The signal from the IR sensor is converted to a voltage proportional to the emissivity of the measurement object and depends on the calibration of the sensor.

Measurement of the humidity of the environment

Humidity sensors are some of the main devices that are used in equipment home use, as well as in industry, stationary medical and environmental engineering. Humidity defines the water content present in the atmosphere, which impact in particular on the health of living organisms, electronic devices are sensitive to moist atmosphere as well as the work of insulating systems of transformers and power lines, especially those running on high and very high voltage. One of the most popular structures of humidity sensors, capacitive sensor, which measures relative humidity. They use a condenser which dielectric is made of higroskopijnego polymer sensitive to humidity changes, causing the capacitance change of measuring capacitor. Such sensors are used, in particular, in monitoring changes in the frequency of electric oscillation of the LC oscillator, during testing of pharmaceutical products. The medication in the drug testing acts as a dielectric which is inserted between the measuring electrodes. The oscillation frequency of the electrical oscillator changes with the humidity of the tested preparation.