Differential Pressure Transmitter D31 Series Delta Mobrey

The model D31 Differential Pressure Transmitter is suitable for measuring pressures from -100mbar to 70bar with maximum working pressures up to 413 bar. The D31 SMART Differential Pressure Transmitters are suitable for measuring differential pressure of gases, vapours and liquids. The active sensing element is a piezoresistive silicon sensor separated from the medium by a diaphragm and by a specially selected type of manometric liquid.  The special design of the active sensing element ensures that it is able to withstand pressure surges and overloads of up to 250/320/413 bar. The casing is made of cast aluminium alloy or 316 stainless steel with degree of protection IP66/IP67. The design of the casing enables the use of a local display, rotation of the display by 90°, rotation of the casing by 0–355° relative to the sensor, and a choice of cable direction.

ATEX certified for use in Zone 0/20 and Zone 1/21 Hazardous Areas and available with 316L, Hastelloy C 276 or Gold wetted parts materials, the D31 SMART Differential Pressure Transmitters are suitable for use in a wide range of applications whether for measuring differential pressure, level or flow. When fitted with a direct diaphragm seal on the Hi side of the transmitter (image on left), the D31 can be used for measuring level in open tanks. One unique feature of all models in the D-Series is the backlit LCD display which facilitates local monitoring in light deficient environments by enhancing display visibility (move your mouse cursor over the image below to illuminate display). 


  1. Cost-Effective

    The D-Series offers customers a high specification and comprehensive product range at very competitive prices

  2. Backlit LCD Display

    A backlit display facilitates local monitoring in light deficient environments by enhancing display visibility

  3. Easily Configurable

    The D-Series transmitters are easily set up and configured either using a standard HART communicator or via Delta’s user-friendly ‘D-Soft’ communication software

  4. Accuracy

    The D-Series transmitters have a standard accuracy of 0.075% with even better accuracy being available upon request


  • ATEX - Flameproof and Intrinsically Safe IECEx - Flameproof and Intrinsically Safe
  • SIL 2 certificate
  • Compliant to NAMUR NE-43
  • High accuracy ±0.075% (better accuracy upon request)
  • Fully HART ® compatible
  • Static pressure limit up to 413 bar
  • 4-20mA, 0-20mA or 0-5mA analogue with digital communications
  • Gold (Au) plated diaphragm option
  • Hastelloy C276 wetted parts option
  • Programmable range, zero shift, characteristic and damping ratio with local panel keys
  • Linearisation of output signal on 20 point curve for specific application is available
  • Write protection option through DKAP-03 communicator, ‘D-Soft’ program or software using library EDDL


The D Series SMART Differential Pressure Transmitter is suitable for a wide range of applications for measuring:

  • Differential Pressure
  • Level
  • Flow

The choice of models available ensures that the Delta Transmitter is suitable for use in:

  • Corrosive atmospheres
  • Resistant to chemical attack

Another Article:


Metrological parameters


  • ≤±0.075% of the calibrated range
  • (≤ ±0.1% for range B1)
  • Special Version: ≤±0.05% of the calibrated range

Long-Term Stability:

  • ≤ accuracy for 3 years
  • ≤ 2x accuracy for 5 years
  • Version code 2: ≤ accuracy for 6 years

Thermal error:

  • for ranges all except B1: ≤ ±0.05% (FSO) / 10°C
  • for range B1: ≤ ±0.08% (FSO) / 10°C

Response Time: 16...480ms (programmable)

Additional electronic damping: 0…60 s

Error due to supply voltage changes: 0.002% (FSO) / V

Download Data Sheet: Differential Pressure Switch D31 Series

Ref: delta-mobrey.com