5.2.2 Active vacuum gauges
Active vacuum gauges combine the sensor itself, which transforms the mechanical magnitude pressure into an electrical magnitude, with a compact electronic control and evaluation unit. They indicate the pressure measured either in the form of an analog measurement signal (0 – 10 V) or a numerical value through a standardized digital interface. They must be supplied with a direct- current voltage (typically 24 V). Power supply units that display the measured values are also available for the active vacuum gauges.
|Vacuum sensor connected by cable to the required electronic power supply and evaluation unit; sensor-specific signaling and supply lines between the sensor and the electronic unit||Vacuum gauge
Passive vacuum gauge
|Vacuum sensor and electronic unit integrated in a housing, power supply with standardized supply voltage (typically 24 V DC); pressure information in the form of an analog output signal (typically 0 – 10 volt) or standard digital interfaces (RS-485, Profibus, DeviceNet)||Active vacuum gauge
Table 5.1: Active and passive vacuum gauges