Emerson Liebert PSA Line-Interactive UPS 500-1500VA User Manual

• The Type-specific properties options relate to communications between the UPS and the host 

computer. These properties vary by connection type; values are automatically detected by Liebert 

MultiLink. The defaults are correct for most installations, but some may be altered if necessary.

For Contact Closure and Serial UPS (for example, MultiLink Agent computer in Figures 1 

and 2), the Type-specific properties box has only one option:

• The Serial Port box displays the port selected during installation. If it is no longer valid, 

select a different port by clicking on your choice. You may also enter the name of the port 

manually. For further information on serial ports, see Appendix A - Operating System 

The Type-specific properties box does not provide choices for USB connections.

For SNMP connections (for example, MultiLink Agent computer in Figure 3), you will see these 

• Hostname or IP address—identifies the UPS
• SNMP Community String—the default is LiebertEM (case-sensitive)
• Trap Listen Port—usually port 162 (Standard SNMP trap port) for communicating 

events (traps) because of SNMP card requirements

• Request Send Port—usually port 161 (Standard SNMP request port) for communicating 

status (gets) because of SNMP card requirements

• Status Rate—Determines how often Liebert MultiLink checks the condition of the UPS.

For MultiLink Basic Notification Source connections (for example, MultiLink Client computer in 

Figure 3), you will see these Type-specific properties:

• Hostname or IP address—identifies another computer (that is running Liebert 

MultiLink version 4.x or 3.x) acting as a “virtual UPS.” The computer that is acting as the 

virtual UPS (i.e., the MultiLink Basic Notification Source) must be running Liebert 

MultiLink version 4.x or 3.x. If you intend to use the MultiLink Basic Notification Source as 

your event source, Liebert MultiLink (on the virtual UPS computer) must include your IP 

address in its list of client targets and have the MultiLink Network Shutdown License 

installed.

• SNMP Community String—the default is LiebertEM (case-sensitive)
• Trap Listen Port—usually port 3029 (Private InterNIC-assigned trap port) for 

communicating events (traps). This must be the same trap port used by the host computer.

• Request Send Port—usually port 3027 (Private InterNIC-assigned request port) for 

communicating status (gets). This must be the same request port used by the host computer.

To finish setting up client computers, add each client to the host computer’s list of targets, as 

described in 8.3.6 - Properties - Clients Tab.

• In  the  Description box, enter a short identifier for the UPS being monitored by Liebert 

MultiLink. This optional field is helpful if the user has more than one UPS. For example, the 

description “PSA-Finance Server” might be used for the Liebert PSA UPS powering the finance 

department’s server.

• When finished, click on the OK button to accept the changes. To close the window without saving 

changes, click on Cancel.