Measuring equipment and apparatus, in particular in relation to pressure, absolute pressure, differential pressure, temperature, density, [ pH value, ] quantity, in particular flow volume, humidity, force, acceleration, path, angle, speed, density or level, filling level; pressure gauges, mano-vacuummeters, barometers, altimeters, thermometers, thermo-hydrometers, hydrometers, pressure probes, flow measuring apparatus, measuring equipment, namely, pressure transmitters, measuring equipment for refrigeration technology and air conditioning technology, [ leak detectors; ][ measurement value recorders, data loggers; ] measuring equipment, namely, transducers; electric measuring transducers with electronic output signals, in particular pressure measuring transducers, differential pressure measuring transducers, level measuring transducers, remote indicators, control and regulating apparatus, flow monitors or checking apparatus, electric relays, electric contactors, switches; position regulators; pressure regulators, electric and fluidic equipment and apparatus, namely, electric supply apparatus, electrical amplifiers, electrical circuitry, electric circuit elements and recording apparatus; calibrators and calibration devices, in particular pressure compensators; electric switches, in particular pressure switches, limit switches, level switches, non-contact magnetic switches, optical, inductive and capacitive switches, electric switches designed as floating switches, operation control instruments or indicators of the presence of metals; electric switching equipment for level control of liquids on the basis of the electrical conductivity of the liquid concerned; electric and electronic control apparatus for speed counting, [ speed control, ] stop-motion detecting, revolution-safety monitoring, level indication, limit monitoring, [ phase control, ] machine control and machine monitoring; electric and electronic control apparatus [ and time relays ]