Access can control fans to maintain setpoint pressure, setpoint flow or fixed speed (pressure/flow independent).

Combinations of two control types is possible. In combination setup, the performance (air flow or speed) of the master fan is a setpoint to the slave fan.


Access has a choice of the following fan control types:


  1. Pressure - fan speed adjustment to maintain constant air pressure.
  2. Flow - fan speed adjustment to maintain constant airflow volume.
  3. Manual - fan speed control signal is maintained at setpoint level. No feedback of pressure, flow or RPM is used.
  4. External - fan speed control signal is regulated according to input reference signal.
  5. Supply air pressure and extract air fan slave - SAF is adjusted to maintain constant supply air pressure. EAF follows the same speed signal (with or without scaling).
  6. Supply air pressure with extract air flow slave - SAF is adjusted to maintain constant supply air pressure. EAF regulated to keep up with the same airflow as the SAF.
  7. Extract air pressure with supply air fan slave - EAF is adjusted to maintain constant extract air pressure. SAF follows the same speed signal (with or without scaling).
  8. Extract air fan pressure with supply air flow slave - EAF is adjusted to maintain constant extract air pressure. SAF regulated to keep up with the same airflow as the EAF.