Almost all UPS systems are fitted with a communications port. This provides a serial connection to one of the supported computers, to give users the ability to interrogate the UPS for historical and real-time information relating to the UPS. The parameters available chiefly relate to the power coming in to the UPS, the power going out of the UPS, and the condition of the UPS itself. This information can be extremely useful for a number of different circumstances. Here are some examples.
1. The UPS loading figures provide important information when adding further equipment to the UPS.
2. If the backup time reduces significantly from previous power outage experiences, when supporting the same load, this indicates that the batteries are ageing and will need replacing soon.
3. If the mains supply is persistently poor over several days/weeks/months, the historical log can provide supportive evidence for any investigations.
Other functionality within the software includes alarm notification and automatic shutdown management. Here is a typical sequence of events when a power outage occurs:
1. Mains Power fails.
2. The UPS sends an 'on battery' signal to the server it communicates with.
3. This signal is relayed across the network to other supported computers.
4. Messages are broadcast to users warning them to save their work and log out.
5. E-mail, and/or pager messages are sent out to alert a system manager to the situation.
Text message alerts can also be sent direct to a mobile using a GSM modem
connected to the serial port of the monitoring server.
6. After 'x' minutes (decided by the system manager), the servers instigate a shutdown procedure.
7. Final warning to users that the system is going down.
8. Special programs are invoked through a script file.
9. The operating system is shutdown.
10. Once the UPS batteries are exhausted, the UPS switches itself off.
When power is restored, power is supplied to the computers immediately, to enable them to boot up, and the batteries in the UPS will begin to re-charge.
As an alternative to a serial connection to a server, a network adapter, or internal network card puts the UPS directly on to the network. This has several advantages:
1. Communication to the supported equipment does not rely on a single server.
2. Monitoring can carried out from anywhere on the network (WAN or LAN).
3. The UPS can be sited remotely from the supported equipment, and still communicate fully.
Network adapters are normally SNMP compliant which enables the UPS to be monitored using a Network Management System such as
HP-Openview, IBM NetView, SunNet Manager, Novell Netware Manager, and others.
Multiple UPS management can be achieved over the network using a Network Management
System. Software is also available which can monitor several different makes of
UPS.