Differential Pressure Switch D33 Series

The D33 Differential Pressure Transmitters is a low cost solution for the measurement of differential pressure of gases, vapours and liquids with SMART “HART” type transmitter technology. 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 model D33 Differential Pressure Transmitter is suitable for measuring pressures from -100mbar to 70bar with maximum working pressures up to 420bar.

From the simple flying leads electric connection to standardized connector IP65/IP67 or even an all St.St. enclosure with internal terminal board, to cover almost all the application. Threaded with rear or flush diaphragm process connection and several type of chemical seal are available, to measure any type of process fluid and condition.

ATEX certified for use with Gas in Zone 0/1 and Zone 20 for Dust. Hazardous Areas and available with 316L, Hastelloy C 276 or Gold wetted parts materials.

The D-Series can also be supplied with Delta’s user-friendly ‘D-Soft’ remote communication software.  Using the HART communication protocol, this software provides users with a convenient way to calibrate, configure and monitor the instrument by connecting it to a PC via Delta’s USB/Bluetooth to HART converter.

D-Soft features include:

  • Identification of individual transmitter
  • Configuration of output parameters
  • Readings of currently measures values
  • Enforcement of output current with a given value
  • Transmitter calibration
  • Zeroing


  1. Cost-Effective
    The D-Series offers customers a high specification and comprehensive product range at very competitive prices
  2. 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
  3. Accuracy
    The D-Series transmitters have a standard accuracy of 0.1% with even better accuracy being available upon request


  • Accuracy +-0.1%.
  • 4-20mA output signal.
  • Fully HART ® compatible.
  • Static pressure limit up to 420 bar.
  • ATEX certified (Intrinsic Safety).
  • Gold plated diaphragm option.
  • Hastelloy C276 wetted parts option.


Accuracy: ≤ ±0.1% of calibrated range

Long-term stability: ≤ accuracy for 3 years

Thermal error:

  • ≤ ±0.08% (FSO) / 10°C
  • max. ±0.3% (FSO) in temperature range -25…80°C

Thermal compensation range: -25…80°C

Zero shift error for static pressure:

  • 0.01% (FSO) / 10 bar for range 3, 4, 5, 6, 7, 9
  • 0.03% (FSO) / 10 bar for range 8
  • 0.06% (FSO) / 10 bar for ranges 1, 2
  • Zeroing the transmitter in conditions of static pressure can eliminate this error.

Response time: 16..230ms (programmable)

Additional electronic damping: 0…30 s

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

Power supply: 7.5...55 V DC (Ex ia 7.5...28 VDC)

Output signal: 4...20 mA, two wire transmission

Download Data Sheet: Differential Pressure Switch D33 Series

Ref: delta-mobrey.com

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