User's Manual

Installing a Liebert iCOM Unit-to-Unit Network
Liebert
®
iCOM
®
92
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
interference.
• 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 98 for details.
5.3 Wiring for Unit-to-Unit Communications—U2U
Cooling units come from the factory-wired for stand-alone operation.
Liebert iCOM U2U Ethernet Network
The Liebert iCOM U2U network must be isolated from other network traffic. The network switch(es)
that connect Liebert iCOMs need to be dedicated to supporting only Liebert iCOM communication.
The U2U network cannot be connected to the building or IT network. If network communication is
ever lost (failed network switch, etc.), all Liebert iCOM-controlled cooling units will continue to
operate as independent units.
The Liebert iCOM can support up to 64 nodes on one network. An input/output board, large display,
and large wall-mount display are each considered one node. Of the 64 nodes that may be connected,
no more than 32 may be input/output boards (32 cooling units). A small display is not considered a
node. Small displays connect directly to input/output boards that do not have large displays attached
to them. Table 18 illustrates how a network can be configured.
Table 18 Sample Liebert iCOM network configurations
Sample
Configuration
Input/Output
Boards
Large
Displays
Small
Displays
Wall Mount
Large
Displays
Private
Switch
Required
12020No
22021Yes
33030Yes
42110Yes
58441Yes
6323200Yes
7322755Yes
8 32 0 32 32 Yes