MEMS pressure transmitter HIE

siliconHART4-20 mA

Product overview
The HIE series are Gefran IMPACT fluid-free pressure transmitters engineered for high-temperature melt/process applications up to 350°C. Process pressure is transferred through a thick process membrane directly to a micromachined silicon sensing element. HIE integrates IMPACT technology with Smart/HART digital communication and is certified for functional safety (SIL2 and PLd).

Key features

• Fluid-free design: no internal filling/transmission fluid.
• IMPACT technology: high-thickness process membrane for mechanical robustness.
• Micromachined silicon sensing element positioned directly behind the contact membrane.
• Digital communication: Smart/HART over 4–20 mA.
• Functional safety certified: SIL2 and PLd.
• Suitable for high-temperature melt/process environments.

Applications

• Process plants: polymer, fibre and resin production.
• High-temperature melt applications where fluid-free reliability is required.
• Installations requiring functional safety certification (SIL2 / PLd).

Technical specifications

• Type: Pressure transmitter, IMPACT fluid-free (Gefran HIE series).
• Communication / Output: 4–20 mA with HART (Smart/HART).
• Measuring ranges: 0–10 to 0–1000 bar (0–150 to 0–15000 psi).
• Accuracy: < ±0.25% FS (H-class); < ±0.5% FS (M-class).
• Rangeability (turndown): 3:1.
• Process temperature capability: up to 350°C.
• Stem thermal drift: < ±0.0036% FS.
• Standard process threads: 1/2-20 UNF, M18x1.5 (depending on version).
• Membrane: high-thickness 15-5 PH stainless steel with GTP+ coating.
• Autozero: on-board option and external autozero available.
• Safety certifications: SIL2, PLd.

Technical notes
The minimal deflection requirement of the silicon sensing element allows the use of a much thicker process membrane (≈15× compared with traditional Melt sensors), eliminating filling fluids and increasing mechanical robustness and reliability in harsh high-temperature melt processes. Multiple mechanical variants (rigid stem, rigid+flexible stem), connector options and thermocouple versions are available to match application needs.