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entire main load center, and I have the option of switching any one of my home's circuit break-
ers either “on” or “off.” This means that I can use my generator to power any circuit inside my
home that I choose. However, please realize that your backup generator has a much smaller
power output than the capacity of all of the circuits in your home, so you will need to use dis-
cretion and understanding when you decide which circuits to activate, and which to turn off.
Using my modest-sized 4 kW generator for example, means that at 220 VAC (to power my
home's 220-VAC load center), I only have a maximum continuous output from my generator of
about 20 amps, and in fact my generator has a 20-amp-rated 220-VAC outlet socket. Looking at
my home's load center, I see a 30-amp 220-VAC circuit for an electric stove, and a 50-amp
220-VAC circuit for my an electric hot-water heater, and my generator does not have adequate
power to supply these circuits, so I know that I must switch the circuit breakers for these items
to the “off” position.
In general, you should also switch any other high-amperage circuit breakers (those breakers
labeled with a number greater than 15 or 20 amps) in your home's electrical subpanel to the
“off” position, since your modest-sized generator will not have the capacity to power these
large loads. These include all of the 220-volt breakers that are commonly identified by a join-
ing bracket that ties two small side-by-side breakers to each other. The disadvantage of this op-
tion (transfer panel) is that it really isn't a suitable do-it-yourself job—I highly recommended
that you enlist the services of a qualified electrician for this type of installation.
Option 2, Manual Transfer Switches
This option does not have all the convenience of the transfer panel, however, it is more easily
installed by the do-it-yourself home handyman. In this option, a manual transfer-switch box is
installed directly alongside the home's main load center. Instead of the entire incoming power
for the home being run through the box, as is the case with the transfer panel, individual cir-
cuits are run from the load center to the transfer switch box. Inside the transfer-switch box are
toggle switches for controlling dedicated home circuits. Each toggle switch has three positions:
generator, line, or off. Similar to the transfer panel, the installer would run a heavy gage set of
wires from the transfer-switch box to a power-inlet box (see fig. 4-12 ) that is connected to your
backup generator via a heavy-duty extension cord (see figs. 4-13 and 4-10 ) with special
220-VAC plugs to fit the power box on one end, and the outlet socket on your generator at the
other end.
The disadvantage of this system is that the installer must choose beforehand which specific
circuits are to be controlled by the transfer switches. For this reason, this option does not have
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