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CNT-SVX07D-EN
Sequence of operations
Dehumidification
The Tracer ZN521 supports a dehumidification feature. Dehumidification is possible if the following
are present:
•
Mechanical cooling is available
•
The heating capacity is located in the reheat position
•
A zone humidity sensor is connected at AI4, or a relative humidity (RH) value is transmitted to
the controller by a BAS.
•
The Space RH Setpoint is valid (configurable using the Rover service tool)
•
Dehumidification is enabled using the Rover service tool
The controller initiates dehumidification if the zone humidity exceeds the humidity setpoint. The
controller continues to dehumidify until the sensed humidity falls below the setpoint minus the
relative humidity offset.
The controller uses cooling and heating capacities simultaneously to dehumidify the space. While
dehumidifying, the controller maintains the zone temperature at the active setpoint.
Note:
Dehumidification is not available for face-and-bypass applications, and cannot be used if
the unit is in the unoccupied mode. Dehumidification disables the economizing function.
Peer-to-peer communication
Tracer ZN521 zone controllers have the ability to share data with other LonTalk-based controllers.
Multiple controllers can be bound as peers, using the Rover service tool, to share:
•
Setpoint
•
Zone temperature
•
Heating/cooling mode
•
Fan status
•
Unit capacity control
Shared data is communicated from one controller to any other controller that is bound to it as a
peer. Applications having more than one unit serving a single zone can benefit by using this feature;
it allows multiple units to share a single zone temperature sensor and prevents multiple units from
simultaneously heating and cooling.
Unit protection strategies
The following strategies are initiated when specific conditions exist in order to protect the unit or
building from damage:
•
Smart reset
•
Low-coil-temperature protection
•
Condensate overflow
•
Fan status
•
Fan off delay
•
Filter-maintenance timer
•
Freeze avoidance
•
Freeze protection (discharge air temperature low limit)
Содержание Tracer ZN521
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