Dell Precision T3400 (Late 2007) - Manual (Page 69)

Setting Up Your Computer
69
Surge Protectors
Surge protectors and power strips equipped with surge protection help
prevent damage to your computer from voltage spikes that can occur during
electrical storms or after power interruptions. Some surge protector
manufacturers include warranty coverage for certain types of damage.
Carefully read the device warranty when choosing a surge protector and
compare joule ratings to determine the relative effectiveness of different
devices. A device with a higher joule rating offers more protection.
NOTICE:
Most surge protectors do not protect against power fluctuations or
power interruptions caused by nearby lightning strikes. When lightning occurs in
your area, disconnect the telephone line from the telephone wall jack and
disconnect your computer from the electrical outlet.
Many surge protectors have a telephone jack for modem protection. See the
surge protector documentation for modem connection instructions.
NOTICE:
Not all surge protectors offer network adapter protection. Disconnect the
network cable from the network wall jack during electrical storms.
Line Conditioners
NOTICE:
Line conditioners do not protect against power interruptions.
Line conditioners are designed to maintain AC voltage at a fairly constant
level.
Uninterruptible Power Supplies
NOTICE:
Loss of power while data is being saved to the hard drive may result in
data loss or file damage.
NOTE:
To ensure maximum battery operating time, connect only your computer to
a UPS. Connect other devices, such as a printer, to a separate power strip that
provides surge protection.
A UPS protects against power fluctuations and interruptions. UPS devices
contain a battery that provides temporary power to connected devices when
AC power is interrupted. The battery charges while AC power is available. See
the UPS manufacturer documentation for information on battery operating
time and to ensure that the device is approved by Underwriters Laboratories
(UL).