Emerson MONITORING OpenComms Manuel D’Utilisation

The OpenComms NIC can use simultaneous connections, sometimes 

requiring three user connections:

• Permanent network connection
• Modbus 485 connection
• Temporary serial connection for configuration/setup

Consult with the network administrator or other responsible party for 

arranging a network drop to the Liebert equipment. The OpenComms 

NIC communicates via standard 10 Base-T Ethernet network connec-

tion. Route the 10 Base-T cable to the Liebert unit and connect to J3, 

the RJ45 jack on the interface card. The OpenComms Network card 

will operate with any 10 Base-T Ethernet, regardless of operating sys-

tem used.

The Modbus 485 connection will use the terminals marked “Repeater.” 

(TB2) The Modbus server uses RTU protocol and will allow for a maxi-

mum of 32 units on 4000ft. of wire on a common line. EIA-485 repeat-

ers may be necessary to accommodate additional units or longer 

cables. Point availability may be referenced in the document, “NIC 

Reference Library,” which may be downloaded at 

 

under the OpenComms product family.

A temporary serial connection to the interface card is necessary for 

configuration and setup.
Using a DB9F-DB9F null-modem cable, connect the “DTE Serial Port” 

P18 to an ASCII terminal or computer running terminal emulation 

application. HyperTerminal® and Procomm® are examples of termi-

nal emulation applications running on Microsoft Windows® operating 

systems. All trademarks are property of their respective owners.