Air Handling Controller – HK Instruments DPT-Ctrl-MOD Series


  • PID-controller
    • Control differential pressure or air flow in duct or across centrifugal fans
    • All parameters (PID) are adjustable via menu and Modbus
  • Multiple field selectable measurement units:
    • Volume flow: m3/s, m3/h, cfm, l/s
    • Velocity: m/s, ft/min
    • Pressure: Pa, inWC, mmWC, kPa, mbar
  • Control output: Voltage (0–10 V)
  • One external input: voltage, thermistor or binary input
  • Outside air temperature compensation function
  • Fixed output function via menu and Modbus

Multifunctional PID controller with differential pressure or air flow transmitter and Modbus communication

DPT-Ctrl-MOD enables to control constant pressure or flow of fans, VAV systems or dampers. In addition, the controller is fully programmable via Modbus. The DPT-Ctrl-MOD includes an Input terminal that enables the reading of multiple signals such as temperature or control relays over Modbus. The Input terminal has one input channel designed to accept 0−10 V, ntc10k, Pt1000, Ni1000/(-LG), and BIN IN (potential free contact) signals.


DPT-Ctrl-MOD series devices are commonly used in HVAC/R systems for:

  • Controlling differential pressure or air flow in air handling systems
  • VAV applications
  • Controlling parking garage exhaust fans


Communication RS-485 Modbus (RTU)
Accuracy (from applied pressure) Pressure < 125 Pa = 1 % + ±2 Pa
Pressure > 125 Pa = 1 % + ±1 Pa
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
Control signal 0…10 VDC
PID-parameters Selectable via menu and Modbus
Zero point calibration via Modbus or by pushbutton
Supply voltage 24 VDC ±10 % / 24 VAC ±10 %
Power consumption < 1.0 W
Output signal via Modbus
Operating temperature -20…+50 °C
Protection standard IP54


HK Instruments DPT-Ctrl-MOD Series Air Handling Controller-DpstarGroup