26
Fig. 45 — Typical IGC Control Wiring Diagram
EconoMi$er
®
X (Factory Option)
The EconoMi$er X system is an expandable economizer con-
trol system, which includes a W7220 economizer module (con-
troller) with an LCD and keypad (see Fig. 46). The W7220 can
be configured with optional sensors.
Fig. 46 — W7220 Economizer Module
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$er X system includes an economizer module,
20k mixed air sensor, damper actuator, and either a 20k out-
door air temperature sensor or S-Bus enthalpy sensors.
Economizer Module
The module is the core of the EconoMi$er X system. The
module 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 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.
CO
2
Sensor (optional)
The CO
2
sensor can be added for Demand Controlled Ventila-
tion (DCV).
SPECIFICATIONS
W7220 Economizer Module
The module is designed for use with 2 to 10 vdc or bus com-
municating actuator. The module includes terminals for CO
2
sensor, Mixed Air sensor, and an Outdoor Dry Bulb sensor. En-
thalpy and other options are available with bus sensors.
User Interface
Provides status for normal operation, setup parameters, check-
out tests, and alarm and error conditions with a 2-line 16 char-
acter 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
UNIT CONTROL
BOARD
IMPORTANT: All inputs and outputs must be Class 2 wiring.