Issues related to the introduction of new control technologies and temperature monitoring at NPPs are being considered, since NPP longterm operation depends on the reliability of process control means. It is promising to build instrumentation and control complexes using one-wire technologies, since the operation information removal and transmission means should be carried out under the conditions of spatial constraints on the location of cabling. One-wire technologies make it easy to build a measurement network of the most complex topology. It is proposed to use DS18B20 universal digital primary measuring transducers as NPP testing equipment. In this regard, scientific and technical interest is a new approach to the measurement of temperature fields based on 1-Wire technology. It was proposed to use UR-1 demagnetizer as a source of a variable electromagnetic field imitating NPP equipment operating conditions. The paper also presents a study for visualization of the generated electromagnetic fields. A Hall sensor is used for measuring the fields under consideration. The proposed method can be used to conduct other similar studies to assess the response of temperature sensors (or other digital sensors) to an external magnetic field. A visualization method is used to evaluate the informational function and a conclusion is made about the applicability of such sensors in the systems of metrological control and monitoring of NPP auxiliary equipment.