HKE NAK – Sodium potassium – HART – SIL2 – PLd



  • The HKE series of Gefran are pressure transmitters with HART communication protocol for use in high-temperature environments.
  • The main characteristic of this series is the capability to read the temperature of the media up to 538°C.
  • The constructive principle is based on the hydraulic transmission of the pressure.
  • The fluid-filled system assures temperature stability.
  • The physical measure is transformed into an electrical measure by means of strain-gauge technology.


  • pressure ranges from: 0-35 to 0-1000 bar / 0-500 to 0-15000 psi
  • accuracy: < ±0.25% FS (h); < ±0.5% FS (m)
  • hydraulic transmission system for pressure signal guarantees stability at working temperature (nak).
  • liquid conforming to rohs directive. nak is defined as a safe substance (gras)
  • quantity of nak contained per model: hke0 series (30mm³) [0.00183 in³], hke1, hke2, hke3 (40mm³) [0.00244 in³]
  • 1/2-20unf, m18x1.5 standard threads; other types available on request
  • autozero function on board / external option
  • inconel 718 diaphragm with GTP+ coating for temperatures up to 538°c (1000°f)
  • 15-5 ph diaphragm with GTP+ coating for temperatures up to 400°c (750°f)
  • hastelloy c276 diaphragm for temperatures up to 300°c (570°f)
  • 17-7 ph corrugated diaphragm with GTP+ coating for ranges below 100bar-1500psi
  • stem material: 17-4 ph