Trane ZN. LonWorks control, Руководство пользователя

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4 CNT-SVX13B-E4
The Tracer ® ZN. unit controller is a
microprocessor-based direct digital
controller that is dedicated to the
control and the optimization of
chilled water terminal units. The unit
controller is designed to provide
improved comfort with a minimum
energy consumption through the use
of custom proportional integral
derivative (PID) control algorithms as
well as intelligent fan speed and
setpoint control strategies.
Moreover, the controller maintains
the discharge air temperature using
a cascade control algorithm. The
discharge air temperature is based
on the difference between the space
temperature and setpoint so the unit
capacity modulates to achieve the
PID calculated discharge air
temperature setpoint, which gives an
incomparable level of comfort.
The controller is factory installed and
pre-commissioned, resulting in a
highly integrated product, reduced
installation and commissioning time.
The following configurations are
supported by the controller:
- 2-pipe cooling only
- 2-pipe chan electric heater
- 2-pipe c electric heater
- 2-pipe changeover
- 2-pipe heating only
- 4-pipe
For those units which require auto
changeover with a 2-pipe system, a
sensor measures the entering water
temperature as to determine
whether the installation is in cooling
or heating mode. Using the entering
water temperature sampling function
(see control features), the auto
changeover units can also be used
with two-way valves. Typically the
control loop includes:
• 1 ZN. LON controller (located into
the unit's control panel)
• 1 return air sensor or 1 remote, wall
mounted, room sensor
• 1 discharge air temperature sensor
• 1 changeover sensor (following the
application)
• 1 or 2 valves and actuators
Description