LX Series Unit Ventilator Controller User's Guide
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Starting Occupied Mode
Occupied mode uses the occupied setpoints that you set in the configuration
wizard. During occupied mode, the UVC uses the damper and outputs to heat or
cool as required to maintain the space within the limits set by the occupied
setpoints. If configured, the UV also controls fresh air intake to maintain CO
2
concentration as configured. Occupied mode begins as result of one of the
following events:
•
A command is received on nviOccManCmd or nviOccCmd. To modify these
network variables, use a computer connected to a network to manually
command nviOccManCmd, or use the building schedule to modify
nviOccCmd.
•
The occupancy switch is closed when both nviOccCmd and nviOccManCmd
are set to OC_NUL, OC_BYPASS, or OC_STANDY.
Ending Occupied Mode
The Unit Ventilator Controller exits occupied mode when any one of the following
events occurs:
•
Another state is commanded through network variable nviOccManCmd. This
method could be used for a manual override from a computer.
•
Another state is commanded through network variable nviOccCmd. This
method could be used with a scheduler node.
•
The occupancy contact opens while nviOccCmd and nviOccManCmd are set
to OC_NUL, OC_BYPASS, or OC_STANDY.
•
The window contact is closed; the occupancy status sets to
OC_UNOCCUPIED.
Unoccupied Mode
Unoccupied mode is the mode used by the Unit Ventilator Controller when the
building is empty overnight or over a weekend. By allowing the space temperature
to vary greater than in occupied mode, unoccupied mode reduces cost. Despite the
greater temperature variance, unoccupied mode keeps the building close enough to
the occupied range of temperature ensuring it can be made ready quickly for
occupancy on a regular schedule.
Starting Unoccupied Mode
Unoccupied mode uses the unoccupied setpoints that you set in the configuration
wizard. It cannot begin if the Unit Ventilator Controller is currently in bypass
mode. Unoccupied mode begins as result of one of the following events:
•
The unoccupied state is commanded by nviOccManCmd. This method could
be used for a manual override.
