For those of you who don't know, a UPS is a battery-operated device that plugs into a wall outlet, provides backup power, and guards your computer gear from damage in the event of a power glitch. A UPS offers greater protection from power problems than a surge suppressor. The typical UPS uses a heavy lead acid battery, and the Pulsar ellipse 500 is no exception. This UPS weighs about ten pounds and provides about 1500 VA worth of power.

A typical UPS is not strong enough to protect your stuff from a lightning strike, but it can protect your computer against common problems such as a power drop when your air conditioner starts. Most importantly, a UPS can help you avoid the pain of losing your important data.

The primary job of a UPS is to provide enough power during a power failure to give you time to shut down the computer safely; it will also provide more robust protection from a power surge than a typical surge suppressor. The battery charges from the wall outlet. The Pulsar ellipse 500 can shut down your computer on its own in the event a power failure occurs while you are not available to shut it down yourself.

I bought this UPS because the power where I work is unreliable. In fact, I ordered two Pulsar ellipse UPS units: one for a Windows XP computer that I reluctantly use and another for my Mac G5. This review is about the UPS I set up on my Mac. I chose this UPS from a Google search. The Pulsar ellipse 500 seemed to meet my needs, at a reasonable price, from an online vendor with whom I have had good experience in the past.

Setting it up was easy. The box contained the UPS, a quick start guide, a manual, and some cables. First, I charged it overnight. The next morning, I downloaded the UPS software from the manufacturer's web site and installed it. The software installation was easy, but it required two restarts of my Mac. After the first restart, I was greeted with a security alert that warned me that an item had been installed in my Mac's system library and it asked me to give it full permissions, which I did. I then had to reboot the Mac again in order for the software to start up. This double restarting is not a big deal, but is is worth mentioning.

The UPS software can detect a power interruption between the wall outlet and the UPS. This UPS is connected to my Mac via a USB cable which was in the box. If the USB cable is disconnected, a warning box pops up. The USB cable must be plugged directly into one of the Mac's USB ports or a powered USB hub. Plugging the USB cable into an non-powered hub will elicit errors.

Setting up the UPS software was a snap! The user interface consists of one preference pane with one slider to set how low the batteries can drain before the software shuts down the computer. The Windows version offers greater functionality, but what's available on the Mac is fine by me. If you never touch the preference pane, it will use the default setting which is to shut down the Mac when the battery reaches 20% of its capacity.

The length of time a UPS can provide power during a power failure depends on how much power is being drawn from it. I only have a Mac plugged into my UPS. My Mac has a 23" Cinema Display plugged into its DVI port. With this configuration, the battery capacity is about 20 minutes. This UPS software can shut down one computer on its own and it has power sockets to supply power to three pieces of equipment. Another three sockets offer enhanced surge suppression only. I pulled this UPS's power cord out of the wall socket to see what would happen. As I expected, after several minutes, the UPS software shut down my Mac cleanly and without any intervention on my part. My Mac started up again just fine.

Why should you use a UPS? If you run your computers all the time, you should use a UPS because the odds of experiencing a power problem increase the longer you leave your computer on. Keep in mind that one of those cheap power suppression strips gives you considerably less protection than a UPS, but you get what you pay for.