Chapter 23: Electrical Power Issues^613
and takes power in “gulps” during its fusing processes. Very few UPS units can handle
the amount and style of this demand. A laser printer can also inject noise back into the
UPS or surge suppressor. Check the documentation of the UPS before connecting a laser
printer to it. Some are rated specifically for this purpose.
Surge suppressors are also extremely hazardous to plug into a UPS. You will see this
warning in the owner’s manuals of both devices.Generators
If you expect you need backup power and protection beyond the 15 to 20 minutes pro-
vided by a UPS, you may want to consider another form of standby power, a power gen-
erator. Whether you are in a home, small office, or large data center, there are power
generators to fit your needs.
A home or small office that absolutely must have a PC available at all times may want to
consider a portable power generator. There are portable and rechargeable models, such as
the X-Power device, shown in Figure 23-6, made by Xantrex Technology (www. statpower.
com). There are also portable gasoline models available from Honda Motors (www.
hondapowerequipment.com/gen.htm), Coleman Powermate (www.colemanpowermate.
com), and several other manufacturers. A portable power generator, like the one in Figure
23-7, can provide you with enough power to run a PC for one to eight hours, depending on
the PC and the size of the gas tank on the generator. Of course, you will need to have a UPS
that lasts long enough for you to get the portable generator on-line. High-end standby power
generators are also available, but these are more typically used as emergency power sources
to large data centers and service provider operations. A small portable generator typically
costs between $300 to $1,000 and a large emergency generator can cost $50,000 or more, plus
the cost of the construction and electrician labor to install one.Protecting Modems and Networks
If lightning strikes within a few miles of your PC and its peripherals, the resulting electri-
cal spike can be transmitted over any metal wire available, including the power lines and
telephone lines. So, in addition to protecting your PC from the dangers on the power line,
you should consider protecting your dial-up modem, DSL bridge or router, or ISDN ter-
minal adapter from power problems. This same risk extends to the network cable to
which your PC may be connected.
Most of the better surge suppressors, and some UPS units as well, now include jacks that
provide line conditioning services on telephone and network connections. Typically, there
are two RJ-11 and two RJ-45 connectors on the unit. The incoming line is connected to one of
the jacks, and the PC or modem is connected to a line attached to an output jack on the surge
suppressor or UPS. Passing this line through the protection device allows the unit to condi-
tion the line and provide over-voltage protection. Many UPS units are network-ready, and
the network adapter can be directly connected to the UPS, which in turn is connected to the
network backbone. This also allows the UPS to communicate over the network in the case of
a severe electrical event.