Emerson Liebert Economizer Solutions Manuel D’Utilisation
Operation
20
Humidity Ratio—Sets the minimum and maximum limits of outdoor air based on the amount of
moisture content. The humidity ratio is set based on pounds of moisture per pound of dry air. This is
equivalent to the dew point temperatures.
Wet Bulb Temperature—Read-only value that displays the outdoor wet bulb temperature. (This
Wet Bulb Temperature—Read-only value that displays the outdoor wet bulb temperature. (This
reading will be in metric values.)
Outdoor Temperature—Displays the actual outdoor temperature based on the Temperature
Outdoor Temperature—Displays the actual outdoor temperature based on the Temperature
Humidity sensor (Sensor C). When this parameter shows OK, the outdoor temperature requirements
have been met to use economization. When NOK is shown, the outdoor temperature is outside the
operating range set in the Liebert iCOM control.
Stop ECO at Setpoint + —Sets the temperature when the Liebert Air Economizer will be disabled
Stop ECO at Setpoint + —Sets the temperature when the Liebert Air Economizer will be disabled
due to an increasing outdoor air temperature. This parameter is added to the return air sensor
setpoint and then compared to the outdoor temperature reading. If the outdoor temperature reading
exceeds the return air temperature setpoint plus this parameter, the Liebert Air Economizer will be
disabled. This is factory-set at 20°F (-6.7°C).
Economizer Mode—Displayed when the Liebert Air Economizer is available for use.
Dew Point Calculated—Displays the actual outdoor dewpoint based on the outdoor sensor.
Enable Economizer—Sets the Liebert Air Economizer operation to one of the following modes.
Economizer Mode—Displayed when the Liebert Air Economizer is available for use.
Dew Point Calculated—Displays the actual outdoor dewpoint based on the outdoor sensor.
Enable Economizer—Sets the Liebert Air Economizer operation to one of the following modes.
These selections only determine if the Liebert Air Economizer is available for use they will not
determine or override damper position. Damper position is always controlled by the sensor set to
control temperature (i.e., Return / Supply Sensor).
Economizer Override—Sets the indoor temperature when the Liebert Air Economizer will be
Economizer Override—Sets the indoor temperature when the Liebert Air Economizer will be
locked out. Even when all other parameters are satisfied, the Liebert Air Economizer will be locked
out when the return air temperature sensor reads this value.
Delay After Fan Start—Sets the delay from the time the unit has been started until the
Delay After Fan Start—Sets the delay from the time the unit has been started until the
ECO EMERGENCY OVERRIDE can be triggered. This allows airflow to pass over the sensors to get
an accurate reading before any emergency modes are activated.
Figure 12 Outdoor sensor data screen
Economizer (page 2 of 3)
to change parameter
to confirm
to select parameter
for next/previous unit
then
then
UNIT 01
SA12
SA13
SA14
SA15
SA16
SA17
SA18
SA19
SA20
SA21
SA22
SA13
SA14
SA15
SA16
SA17
SA18
SA19
SA20
SA21
SA22
PASSWORD (Actual Level 3)
????
Outdoor Air Sensor Temperature
79°F
Outdoor Air Sensor Humidity
33.0%
Outdoor Air Pressure
1013 .2hPa
Saturation Pressure WaterVapor
33.8hPa
Saturation Pressure Ice
42.8hPa
Partial Pressure (Water Vapor )
11.1hPa
Volume Mixture Ratio (ppm/lol)
0.0ppm
Humidity Ratio (g/kg wet)
6.8g/k
Wet Bulb Temperature
59°F
and