Bryant 548J*17 D Series, Руководство по установке

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EconoMi$er
R
X (Factory--Installed Option)
C14154
Fig. 36 -- W7220 Economizer Module
Product Description —
The EconoMi$er X system is an expandable economizer
control system, which includes a W7220 economizer
module (controller) with an LCD and keypad. The W7220
can be configured with optional sensors.
The W7220 economizer module can be used as a
stand--alone economizer module wired directly to a
commercial set--back space thermostat and sensors to
provide outside air dry--bulb economizer control.
The W7220 economizer module can be connected to
optional sensors for single or differential enthalpy control.
The W7220 economizer module provides power and
communications for the sensors.
The W7220 economizer module automatically detects
sensors by polling to determine which sensors are present.
If a sensor loses communications after it has been
detected, the W7220 economizer controller indicates a
device fail error on its LCD.
System Components —
The EconoMi$er X system includes an economizer module,
20k mixed air sensor, damper actuator, and either a 20k
outdoor air temperature sensor or S--Bus enthalpy sensors.
Economizer Module: This is the core of the EconoMi$er X
system, is mounted in the unit’s control box, and includes
the user interface for the system. The W7220 economizer
module provides the basic inputs and outputs to provide
simple economizer control. When used with the optional
sensors, the economizer module provides more advanced
economizer functionality.
S--Bus Enthalpy Control Sensors: The S--Bus enthalpy
control sensor is a combination temperature and humidity
sensor which is powered by and communicates on the
S--Bus. Up to three sensors may be configured with the
W7220 economizer module. See page 29 for details.
CO
2
Sensor (optional): A CO
2
sensor can be added for
Demand Controlled Ventilation (DCV).
Specifications
W7220 Economizer Module —
The module is designed for use with 2 to 10 Vdc or bus
communicating actuator. The module includes terminals
for CO
2
sensor, mixed air sensor, and an outdoor dry bulb
sensor. Enthalpy and other options are available with bus
sensors.
User Interface: Provides status for normal operation,
setup parameters, checkout tests, and alarm and error
conditions with a 2--line 16 character LCD display and
four button keypad.
Electrical —
Rated Voltage:
20 to 30 Vac RMS, 50/60 Hz
Transformer: 100 va maximum system input
Nominal Power Consumption (at 24 Vac, 60 Hz):
11.5 VA without sensors or actuators
Relay Digital Output Rating at 30 Vac (maximum
power from Class 2 input only):
1.5A run:
3.5A inrush at 0.45PF (200,000 cycles) or
7.5A inrush at 0.45PF (100,000 cycles)
External Sensors Power Output: 21 Vdc

5% at 48mA
IMPORTANT : All inputs and outputs must be Class 2
wiring.
Inputs —
Sensors:
NOTE
: A mixed air (MA) analog sensor is required on
all W7220 units; either an outdoor air (OA) sensor for dry
bulb change over or an OA bus sensor for outdoor
enthalpy change over is required in addition to the MA
sensor. An additional return air (RA) bus sensor can be
added to the system for differential enthalpy or dry bulb
changeover. For differential dry bulb changeover a 20k
ohm sensor is required in the OA and a bus sensor in the
RA. DIP switch on RA bus sensor must be set in the RA
position.
Dry Bulb Temperature (optional) and Mixed Air
(required), 20k NTC :
2--wire (18 to 22 AWG);
Temperature range --40 to 150
_
F (--40 to 65
_
C).
Temperature accuracy --0
_
F/+2
_
F
Temperature and Humidity, C7400S1000 (optional):
S--Bus; 2--wire (18 to 22 AWG)
Temperature: range --40 to 150
_
F (--40 to 65
_
C)
Temperature accuracy --0
_
F/+2
_
F
Humidity: range 0 to 100% RH with 5% accuracy.
NOTE
: Up to three (3) S--Bus sensors may be connected
to the W7220 economizer module. For outdoor air (OA),
return air (RA) and discharge (supply) air (DA).
4 Binary inputs:
1--wire 24 Vac + common GND (see Fig. 39 on page 30
for wiring details). 24 Vac power supply: 20 to 30 Vac
50/60Hz; 100 VA Class 2 transformer.