Differential Pressure Transmitter – HK Instruments DPT-MOD Series


  • Two selectable functions:
    • Measure and monitor in-duct volume flow, velocity or differential pressure
    • Measure and monitor air flow across centrifugal fans
  • Multiple selectable measurement units:
    • Volume flow: m3/s, m3/h, cfm, l/s
    • Velocity: m/s, ft/min
    • Pressure: Pa, inWC, mmWC, kPa, mbar
  • Modbus communication protocol

Multifunctional differential pressure transmitters with air flow measurement and Modbus communication

DPT-MOD is a multifunctional transmitter for measuring volume flow, velocity, and static and differential pressure. The measurements can be read and the configuration done via Modbus communication. DPT-MOD requires less wiring than the traditional 3-wire transmitters because multiple devices can be connected on serial line.

The DPT-MOD is used for measuring air flow or low pressures of air and non-combustible gases in order to monitor and control building automation, HVAC and cleanroom systems. It can also be used with several different measurement probes such as FloXact™ or pitot tube, and air dampers.

DPT-MOD series device options offer:

  • AZ (autozero) function for automatic zero point calibration,
    eliminating the need for periodic manual autozeroing
    to ensure long term accuracy


Communication: RS-485 Modbus (RTU)
Accuracy (from applied pressure): Pressure < 125 Pa = 1 % + ±2 Pa
(model 2500) Pressure > 125 Pa = 1 % + ±1 Pa
Accuracy (from applied pressure): Pressure < 125 Pa = 1.5 % + ±2 Pa
(model 7000) Pressure > 125 Pa = 1.5 % + ±1 Pa
Zero point calibration: automatic with autozero element (-AZ), by pushbutton or via Modbus
Measuring units: Pressure: Pa, kPa, mbar, inchWC, mmWC, psi
Flow: m3/s, m3/hr, cfm, l/s, m/s, ft/min
Measuring element: MEMS, no flow-through
Supply voltage: 24 VAC ±10 % / 24 VDC ±10 %
Power consumption: < 1.0 W
Output signal: via Modbus
Response time: 1.0−20 s, selectable via menu or via Modbus
Operating temperature: -20…+50 °C (with autozero calibration -5…+50 °C)
-40…+50 °C (-40C model)
Protection standard: IP54


HK Instruments DPT-MOD Series Differential Pressure Transmitter-DpstarGroup