Even the briefest of power failures can cause your Mac to shut off. At a minimum, this means time wasted while you wait for your Mac to restart. Worse, you lose any unsaved work. Even worse--especially if you don't have a separate surge protector--there is a small risk that your Mac may get damaged when the power returns.
To prevent all of these hassles, consider investing in an Uninterruptible Power Supply (UPS). Also referred to as a battery backup, these devices keep power going to your computer after a power failure. This gives you the critical time needed to save files and gracefully shut down the Mac while you wait for power to be restored.
One of the best-known makers of battery backups is American Power Conversion (APC). However, if you own an Intel Mac and are using a recent version of Mac OS X 10.5 (Leopard), you may want to look elsewhere for a UPS. APC devices are likely to give you grief.
I first became aware of the problems via a friend. He discovered that the main part of his Energy Saver System Preferences pane had gone completely blank. Disconnecting his APC backup restored the pane's contents. He took all the relevant hardware to his local Apple Store. The Genius told him: "APC units don't work with Intel Macs above Mac OS X 10.5.4."
Seeking further confirmation of this statement, I turned to the Web. I quickly learned that APC's PowerChute software is not compatible with Leopard. By itself, this is not a great cause of concern, as you should be able to use Energy Saver instead (unless your Energy Saver text disappears). However, even with Energy Saver appearing correctly, other symptoms may emerge. You may have trouble putting your Mac to sleep; whenever you try, the Mac may immediately re-awaken. Or you may find that the option to have the APC unit shut down your Mac after a power failure does not work. While not every APC owner with an Intel Mac reports having these symptoms, many do.
I held out hope that APC's Web site might provide further illumination. I was wrong. Instead, I was dismayed to find that its Knowledge Base was hopelessly out of date. One article, ironically highlighted as "updated," contained a reference to the Extensions Manager control panel, a software relic from Mac OS 9. Another "updated" item, covering APC compatibility with Macs, never even mentions Leopard. Instead, the list ends with Mac OS X 10.4.8.
I talked with an APC representative about these matters. She confirmed that PowerChute may have problems with Mac OS X versions beyond 10.4.8. Even when used with older compatible versions of Mac OS X, you may need to "disable sleep mode," as described here. With newer versions of Mac OS X, APC's recommendation is to use Energy Saver instead of PowerChute. APC is not aware of the cited incompatibilities between its backup products and Energy Saver, but did not rule out that they may exist. However, the representative pointed out that such problems may be more attributable to Apple's software than to APC's hardware. For example, a similar "re-awaken" symptom may occur when using "smart" power strips and a Mac.
Bottom line: While they may work fine, I would advise caution when purchasing an APC battery backup. Make sure you can return it if it does not perform as expected.
This story, "Bugs & Fixes: Be Wary of APC Battery Backups" was originally published by Macworld.