FEMA Bubbler Pressure Transmitter: Precise Level Measurement Without Media Contact

The FEMA bubbler pressure transmitter is the reliable solution for hydrostatic pressure and level measurement in a wide variety of liquids. The device operates on the bubbler principle: a pump generates pressure in a measuring tube (up to 50 m long), and the hydrostatic pressure is precisely measured as the air bubbles exit.

Since there is no direct contact between the sensor and the medium, the FEMA is ideally suited for aggressive and abrasive media.

Advantages of the Measurement Method

• No Wear: The sensor technology does not come into contact with the liquid. Any media-resistant material can be used for the pipe or tube.

• Unaffected by Foam: Unlike ultrasonic sensors, foam formation has no influence on the measurement.

• Cost-Effective: No complex mechanical constructions are required below the tank, making the system a cost-effective alternative to radar technology.

Smart Operation

The LCD display clearly shows current measured values, switching points, and diagnostic data. The system can be programmed directly via four buttons. For irregularly shaped tanks, up to 20 calibration points can be set for exact volume calculation (linearization).

Areas of Application

• Wastewater treatment plants, pump and well houses.

• Chemical industry and food production.

• Special vehicle construction (water and fuel tanks).

Technical Data at a Glance

• Measuring Ranges: 0...50 mbar, 0...100 mbar, 0...200 mbar, 0...350 mbar, 0...1000 mbar.

• Outputs: Analog 4...20 mA and 0...10 V.

• Interfaces: RS232 (standard), optional CANopen or Profibus.

• Accuracy: ±1% FS (combined error).

• Power Supply: 24 VDC (±20%).

• Protection Class: IP65.

• Housing: Die-cast aluminum, plastic or plastic with EMC coating.

• Pressure Connection: For 6 mm plastic tubing (e.g. Nylon, PA, PUR, Hytrel)[cite: 6].