measuring, signalling and checking, and supervising apparatus and instruments, namely temperature, pressure, moisture, fluid quantity, fluid level, fluid flow, concentration of gas and liquids, electric conductivity and electrochemical sensors, electrical and electronic probes, meters, electrical and electronic indicators, transducers and transmitters; electric and electronic control and regulating apparatus, namely, gas pressure regulators, liquid pressure regulators, thermostats, hygrostats and process controllers for controlling temperature, pressure, moisture, concentration of gas and liquids, fluid quantity, fluid level, fluid flow; Protective apparatus and safety devices, in particular for influencing process engineering processes, namely, temperature, pressure, moisture, fluid quantity, fluid level and fluid flow switches, electric and electronic power switches and electrical and electronic fuses; level switches, float switches for regulation of rising or falling fluid level; level measurement apparatus sensors and apparatus for liquid or gas analysis, sensors and apparatus for measuring electrochemical measurement variables, including electrolytic conductivity, pH value or redox potential; Temperature sensors, Pressure sensors; Flowmeters; force sensors; Strain sensors; Computer Software for controlling, regulating and parameterisation of apparatus, instruments and equipment for measuring, signaling and checking, namely temperature, pressure, moisture, fluid quantity, fluid level, fluid flow, concentration of gas and liquids, electric conductivity and electrochemical sensors, electrical and electronic probes, meters, electrical and electronic indicators, transducers and transmitters; Apparatus for recording, transmission or reproduction of sound or images; Electric and electronic level indicators, data loggers and pressure recorders, temperature recorders, flow recorders and recorders for ionic activity