Emerson Liebert iCOM - Manual (Page 48)

Installing a Liebert iCOM Unit-to-Unit Network
42
5.0 I
NSTALLING A
L
IEBERT I
COM U
NIT
-
TO
-U
NIT
N
ETWORK
Connecting multiple Liebert iCOM-controlled cooling units in an Ethernet Unit-to-Unit (U2U) net-
work enables the units to work together to achieve efficient cooling and humidity control of the condi-
tioned space. Networking enables setting up the cooling units to exchange data for various modes of
operation:
• Teamwork
• Lead/Lag-Standby
• Rotation
• Cascade
However the cooling units are set up, a large display may be used to control and view the operational
status of individual units or of the entire system.
5.1 Placement of Cooling Units
Refer to the cooling unit product manuals for details on installation. Also consider these factors when
planning for installation of cooling units with Liebert iCOM controls:
• heat load in the conditioned space
• cooling air distribution
• number of operating units versus number of standby cooling units
• location of the network switch—An Ethernet cable cannot exceed 328 feet (100m)
5.2 U2U Hardware: Cables and Network Switch
Plan wiring runs for U2U communication when designing the layout of your conditioned space. In
addition to general good wiring practices, take into account:
• Ethernet CAT5 or greater cable is required for interconnecting the units.
• Maximum distance must not exceed 328 feet (100m).
• A device to boost the Ethernet signal may be used to exceed the 328 feet (100m) length limitation.
• Ethernet network should be private—set up only for management and control of the cooling units.
• Keep control and communication cables away from power cables to prevent electromagnetic inter-
ference.
• Do not bend cables to less than four times the diameter of the cable.
• Do not deform cables when securing in bundles or when hanging them.
• Keep cables away from devices that can introduce noise into them, such as machines, fluorescent
lights, and electronics.
• Avoid stretching Ethernet cables—tension when pulling cables should not exceed 25 pounds
(11kg).
• Do not secure Ethernet cables with any method that might damage them; use approved hangers,
such as telephone wire/RG-6 coaxial wire hangers, available at most hardware stores.
Minimum Network Switch Requirements
• IEEE 802.3; IEEE 802.3u
• 10/100 Mbps speed
• Multiple 10/100 RJ-45 ports—one shared; RJ-45 Uplink port
The Liebert vNSA
™
is an approved powered network switch designed to support Liebert iCOM U2U
networks. See Liebert vNSA on page 47 for details.
NOTE
The maximum number of cooling units that may be interconnected is 32.