Abstract: A pressure sensor for monitoring a pressure of an agressive media in a pressure range of about 0.8 to 50 bar, especially for monitoring refrigeration plants, air conditioning plants, or heat pumps, with the sensor including at least one pressure transducer and a mechanical-electric transducer connected to the pressure transducer with the mechanical-electric transformer being in the form of a plate condenser. The pressure transducer and the mechanical-electric transducer are disposed laterally adjacent each other and connected together by a relatively long transmission lever which is mounted at only one end thereof whereby it is possible, in a relatively small space, to realize a large transmission ratio thereby enabling the tying together of the pressure to be determined with a changeable capacity of the plate condenser so that a very steep characteristic line and thus a very high precision of response.