What is it
- The Deltapilot FMB50 is a hydrostatic (pressure-based) level transmitter sensor, part of the Deltapilot M line.
- It is used to measure level (or pressure) of liquids or paste‐like media by detecting the hydrostatic pressure at a point (usually near the bottom of a tank).
Key Features
|
Feature
|
Data / Specification
|
|
Measuring principle
|
Hydrostatic / Pressure measurement.
|
|
Measuring range
|
From 0.1 bar to 10 bar relative pressure, which translates to up to roughly 100 m of water head.
|
|
Accuracy
|
Standard ±0.2%, with an optional ±0.1%.
|
|
Temperature range (process medium)
|
–10 °C to +100 °C (can tolerate up to +135 °C for short periods in some versions).
|
|
Overpressure / max process pressure
|
Up to 40 bar overpressure limit; process pressure rating matches measuring cell.
|
|
Materials (wetted parts / membrane etc.)
|
316L stainless steel, Alloy C, optional coatings (e.g. AuPt). Membrane options include gold-rhodium etc.
|
|
Special measuring cell
|
“Contite” measuring cell: hermetically sealed, condensate resistant; helps with reliable performance in humid or condensing environments.
|
Applications
- Used in both open and closed containers / tanks.
- Works with liquid and paste-like media. So even slurries or viscous fluids, as long as pressure transmission is possible.
- Not significantly affected by foam formation (which can cause issues for some other level sensors).
- Process and hygienic applications (e.g. food, pharma) where cleaning, material compatibility, and possibly certifications are important.
- It is compatible with safety-instrumented systems (SIL2).
Communication / Integration
- The device can output 4-20 mA with HART protocol.
- Also available with PROFIBUS PA and FOUNDATION Fieldbus interfaces, depending on configuration.
- Local display and menu-guided commissioning (for setting up zero, span, offsets etc.).
Advantages / What Makes It Good
- The sealed Contite cell means it handles condensate well; in cold or humid conditions, or where condensation inside sensor housings is an issue, this helps prevent measurement errors.
- Good accuracy, stability and minimal temperature effects.
- Versatile mounting options (threads, flush hygienic, flanges etc.) so it can be used in many tank types.
- Overpressure safety helps with process upsets. SIL2 capability helps in safety-critical environments.
Limitations / Considerations
- Because it measures hydrostatic pressure, fluid density matters: for a given pressure reading, the height (level) depends on density. If the density changes, you may need correction or use of dual sensors / differential setups.
- Installation must ensure that the sensor's zero point is well defined; avoid mounting in locations that cause turbulence, pressure shocks, or where foaming or sludge may accumulate on the membrane.
- For very high temperature, or extreme chemical compatibility, check material options and coatings.
