KMC Controls BAC-4000 series, Инструкция по установке, эксплуатации и применению

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Automatic cooling
and heating
changeover
The AppStat can be set to automatically change between the heating and
cooling modes.
If the space temperature rises above the active cooling setpoint, the
mode is set to cooling.
If the space temperature falls below the heating setpoint, the mode is set
to heating.
For fan coil models, the changeover is immediate. For other models, the
changeover does not take place until the time set by Fan Off Delay expires.
Scheduling
occupancy
The schedule in the controller is a standard BACnet schedule object. It can be
changed from the display by a technician with Password 2 or a BACnet
operator workstation.
The internal occupancy schedule changes the AppStat between the occupied
(
Active ) and unoccupied ( inactive ) states. If the AppStat includes a motion
sensor, the motion sensor may change the AppStat between occupied and
standby based on motion detected in the space.
See also the topic Occupancy, motion sensing, and standby on page 67 .
Dehumidification
sequence
Dehumidification control is available only on models with internal humidity
sensors. Dehumidification is not available for fan coil units configured for
two-pipe operation.
The AppStat can run the dehumidification sequence only if the heating and
cooling modes are set to automatic. The dehumidification sequence can then
start if the space humidity rises above the value of Dehumidification Setpoint.
Dehumidification stops when the space humidity drops to a value below the
Dehumidification Setpoint minus the value of Dehumidification Differential.
The dehumidification setpoint and differential are both adjustable from the
user interface.
When Dehumidification is active, cooling output is activated to 100%. Heating
then reheats the discharge air to maintain the space temperature to the value
of Active Cooling setpoint.
The controller continuously runs the fan during dehumidification regardless
of other fan settings.
Fan status
Fan status is a second function of the Discharge Air Temperature (DAT)
input. The function requires a normally closed fan status switch connected
across the DAT input terminals. When the fan is started at any speed, the
AppStat program waits 10 seconds for the Fan Status switch (FST) to open. If
the status switch does not open within 10 seconds after the fan is commanded
to start, all heating and cooling is commanded to stop heating and cooling at
Section 5: Sequences of operation KMC Controls, Inc.
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