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.

Design Designation
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
Measuring transformer

Table 5.1: Active and passive vacuum gauges