Trane Tracer ZN517, Инструкция по установке и эксплуатации

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Fan operation
CNT-SVX12C-EN 41
trol an air damper actuator for two-position control, configure the Tracer
ZN517 for economizing (economizing will not function).
Fan operation
The Tracer ZN517 can be configured to run continuously at a single speed
or to cycle on and off automatically. If configured for continuous opera-
tion, the fan runs continuously during the occupied, occupied standby,
and occupied bypass modes. If configured for cycling operation, the fan
will cycle if the temperature is away from setpoint during the occupied,
occupied standby, and occupied bypass modes. During the unoccupied
mode, the fan cycles regardless of the fan configuration.
Peer-to-peer communication
Tracer ZN517 unitary 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 serv-
ing 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.
Economizing
Economizing (also referred to as “free cooling”) uses outside air for cool-
ing. The Tracer ZN517 provides two triac (3-wire floating point) outputs
to control the damper actuator. One output opens the actuator; the other
closes it. The controller also provides analog inputs for both a discharge
air temperature sensor and an outside air temperature sensor. While
economizing is enabled, the controller uses a discharge air temperature
(DAT) control loop to maintain proper temperature control. The controller
opens the outside air damper, turns on the fan, and attempts to maintain
a user-defined discharge air temperature. If the outside air is unsuitable
for economizer operation, the outside air damper will close and normal
operation (DX cooling) will be activated. Economizing plus DX cooling is
initiated only when economizing alone cannot meet the zone’s cooling
requirements.
To enable this function, set DIP switch 3 to
ON
(see “DIP switch settings”
on page 30).