Sensors

Sensors, that are inserted in the production process environment record environment condition and dynamics of its alterations. Production environment could be a container, in which lies the product or intermediate product (for example, paste compound, milk at different stages, beer yeast or leaven, chemical product mass etc.) surrounding atmosphere, or the product itself (for example, for production of meat products temperature sensors are inserted in the product itself). Range of the usable sensors might be very wide, however for the production it is common to use only sensors approbated in practice, as possible sensor error may provide incorrect information about procedure of the process.

In industry the most popular sensors for measuring of theses parameters are: temperature, pressure, pH, flow in capacity and aggregation indices, humidity. Of course there could be sensors and devices for measurement of other values too, selection and adequacy of which, in any case, is determined by the exact demands for its application. For example in food industry outer encasement of the sensor should be made from the stainless steel or other inert material. Demands lessen (but not always) if the sensor should be inserted in the environment, which has no direct contact with the produced product (for example, thermostat water in the encasement of technological tank).

By choosing sensor without the above mentioned, it is important to take into consideration its precision (distinction ability)', inertial characteristics, stability and stability in the given production conditions. For example, quite often temperature regulation problems do not occur due to the distinction ability but because of the inertial characteristics. It occurs in a way that sensor reacts to the environment temperature alterations with delay. In such case you should choose smaller mass temperature sensor in construction of which other parameters from which depends inertia are optimized too. Accordingly, physical characteristics of other sensor should be analyzed in the context of concrete application. Only in such way it is possible to find out its adequacy and if necessary to take additional actions for improvement of measurement correctness.

 

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