LX Series Unit Ventilator Controller User's Guide
35
Starting Bypass Mode
The Unit Ventilator Controller can be commanded to enter bypass mode by either
nviOccManCmd or by nviOccCmd. See the
Network Variables Used for Mode
The Unit Ventilator Controller enters bypass mode when any of the following
occurs during unoccupied or standby mode:
•
The bypass button on the space temperature sensor is pressed.
•
The bypass contact is closed.
Note:
The Unit Ventilator Controller does not enter bypass mode if the bypass
time is set to zero.
Ending Bypass Mode
Bypass mode ends as a result of one of the following events:
•
Occupancy contact is closed–the Unit Ventilator Controller exits bypass mode
and enters occupied mode.
•
The window contact is closed
•
The bypass timer expires–the Unit Ventilator Controller enters the currently
scheduled mode, or the mode currently commanded by the occupancy contact.
If bypass mode ends due to the expiration of bypass time and nviOccManCmd is
set to OC_BYPASS, the controller sets nviOccManCmd to OC_NUL. This
scenario returns occupancy control to a scheduler using network input nviOccCmd
or to an occupancy contact.
If nviOccManCmd is not set to OC_NUL, it has priority over nviOccCmd and the
occupancy contact.
Standby Mode
In standby mode, the space temperature is allowed a greater amount of variance
than in occupied mode. Like unoccupied mode, the space is maintained at a
temperature close enough to the occupied setpoints ensuring it can be made ready
for occupancy quickly. Standby is intended for areas such as meeting rooms that
are intermittently occupied during the normal working day.
Starting Standby Mode
Standby mode setpoints are entered during the Unit Ventilator Controller
configuration.
The Unit Ventilator Controller enters standby mode as a result of:
•
a scheduler node writing to nviOccCmd, or
•
an operator writing a command to nviOccCmd and/or nviOccManCmd