User manual
Operation
33 Liebert
®
iCOM
®
3.3.2 Outdoor Air and Return Air Temperature and Humidity Sensor Connections
The Liebert Air Economizer
™
ships with sensors to determine the temperature and humidity of return air
and outdoor air. The sensors and wiring to connect them are in boxes inside the Liebert Air Economizer:
• Outdoor air sensor
• Return air sensor
• Supply air thermistor (factory-connected to the main interface board)
These must be installed and connected to the primary cooling unit. The outdoor air sensor and return
air sensor connections for the Liebert DS
™
and Liebert CW
™
are shown in Figure 31. Connect the
supply air thermistor as shown in Figure 32 (it must be routed from the cooling unit and secured).
The illustration shows connections for the Liebert DS and Liebert CW.
NOTICE
Turn Off all power to the indoor cooling unit before connecting cables or wires. Failure to do so
may damage this equipment.
Figure 31 Temperature and humidity sensor connections—Liebert DS and Liebert CW
B
C
D
DETAIL CDETAIL B
Both Sensors and Cables
are Shipped in Boxes
Inside the Liebert
Air Economizer
Outdoor Air T/H
Sensor
(identified with
outdoor label)
Return Air
T/H Sensor
DETAIL D
Connect P67 on the
Control Board to P66 on the
Return Air T/H Sensor
Using Cable Provided
Secure Ring Terminal
(for Sensor Cable Shield)
Into the Back of the Electric Box
(Earth Ground)
Mount Return Air
T/H Sensor Indoors,
Above Unit Return
Connect P67 on the
Return Air T/H Sensor
to P66 on the Outdoor
Air T/H Sensor Using
Cable Provided
Connect P66 on the
Return Air T/H Sensor
to P67 on the Control Board
Using Cable Provided
Mount Outdoor
Air Sensor Inside
Outdoor Air Plenum
Secure Ring Terminal
(for Sensor Cable Shield)
Into Metal Duct
(Earth Ground)
Connect P66 on the
Outdoor Air T/H Sensor
to P67 on the Return
Air T/H Sensor
Using Cable Provided
Route Cable Through
Customer-Created Hole
In Plenum, Then Seal
Outdoor Air
T/H Sensor
Return Air
T/H Sensor
FRONT VIEW
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DPN001449
Pg. 4, Rev. 2