AP Expert VT-110, User Manual

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11
Air Inlets
Topics Covered in this Chapter
▪ Air Inlets: How it Works
▪ Configuring Air Inlet Parameters
▪ Calibrating the Inlets
▪ Configuring the Inlet Resets
▪ Actuator Reset: How it Works
▪ Opening Compensation According to Temperature or Static Pressure: How it Works
▪ Setting the Temperature and Static Pressure Compensation
▪ Selecting the Static Pressure Compensation Stages
▪ Setting the Static Pressure Setpoints
Air Inlets: How it Works
The controller can control the opening of 1 air inlets. The opening of this device can either be defined by a
potentiometer or with a timer. Set the operating mode of the air inlet in the Installation Setup.
When using the inlet output, the user has to associate an inlet opening with the start-up of each fan stage.
As the room temperature increases and new stages are activated, the air inlet opens and closes
accordingly.
Inlet opening in minimum ventilation
The inlet is at its “Closed” position during the Off Time portion of a minimum ventilation cycle and opens
to its minimum ventilation position during the On Time .
Over-opening of the air inlet
A supplementary stage can be defined in order to continue opening the air inlet beyond the activation
temperature of the last ventilation stage. This over-opening stage is used to direct the airflow more effi-
ciently during periods of warm weather.
The air inlet can either reach its over-opening position right away when the room temperature reaches a
certain point or it can reach its over-opening position gradually as the room temperature departs from the
start temperature of the last fan stage. In either case, the inlet reaches its full over-opening position at: On
T° of the last fan stage + Over-opening bandwidth. You can enable the over-opening function for the air
inlets in the installation setup menu.
Security function for potentiometer-based inlets
If the potentiometer is defective, the controller operates in security mode. If the room temperature is 2°F
(1.1°C) above the setpoint, the inlet opens according to the following cycle: 5 seconds On, 120 seconds
Off. If the room temperature is 2°F (1.1°C) below the set point, the inlet closes according to the same
cycle.
890-00081 Expert VT-110 41