Critical Technical Advantages
-
Elimination of “Capillary Issues”: Traditional dp systems often drift when the sun hits one capillary and not the other, causing the fill-fluid to expand unevenly. The FMD72 uses a digital connection, meaning the signal is immune to ambient temperature fluctuations, icing, or clogging of impulse lines.
-
Robust Metallic Sensors: The piezoresistive sensors feature a fully welded metal diaphragm. This design is ideal for high-pressure environments and processes where metallic wetted parts (like 316L or Hastelloy) are required for chemical compatibility or mechanical durability.
-
Hygienic Safety: The FMD72 offers small, flush-mounted process connections specifically designed for hygienic applications. This ensures there are no “dead legs” or pockets where bacteria can grow, making it ideal for the food and life sciences industries.
-
Multivariable Data via HART: A single system provides the calculated level (differential pressure), the head pressure (absolute), and the individual temperatures of the sensor modules. This allows for comprehensive monitoring of the vessel’s internal environment.
-
Reduced Risk of Leakage: Traditional impulse lines are notorious for leaking process media. The FMD72 keeps the process sealed at the sensor point, significantly enhancing site safety and reducing environmental risks.
-
Flexible Installation: Because the sensors are connected via flexible digital cables, the transmitter can be mounted in an easily accessible location at eye level, away from the top of the tank or high-heat zones.
Technical Performance Matrix
| Feature | Details |
| Measuring Principle | Electronic Differential Pressure (2 Sensors) |
| Sensor Type | Piezoresistive (Metallic membrane) |
| System Accuracy | Up to ±0.07% |
| Measuring Range | 400 mbar to +40 bar (6 to 600 psi) |
| Process Temperature | -40 to +125°C (Optional 250°C / 480°F) |
| Output | 4 to 20mA with HART |
| Approvals | ATEX, IECEx, Hygienic (3-A, EHEDG) |
Primary Applications
-
Pressurized Storage Tanks: Precise level measurement in tanks where the gas phase pressure varies significantly.
-
Distillation and Evaporation: Monitoring levels and pressure drops in columns where vacuum and pressure conditions fluctuate.
-
Hygienic Process Vessels: Level measurement in food, beverage, or pharmaceutical tanks requiring flush-mounted, cleanable sensors.
-
Tall Process Towers: Where traditional capillary systems would suffer from excessive temperature-induced errors due to the vertical distance between measurement points.
-
Cold Climate Operations: Applications where traditional impulse lines would require expensive heat tracing to prevent freezing or “slugging.”
