An increase or decrease in the primary voltage can also be obtained
by the installation of a transformer in the line to provide a fixed voltage
drop. A distribution transformer, connected as an autotransformer, may
be used to boost or buck the feeder voltage at the point of its installation.
The percentage of boost or buck will depend on the ratio of the primary
and secondary coils, including the tap used, of the transformer selected.
The capacity of the unit is determined by the current-carrying capacity
of the secondary coil, through which the entire line current will flow.
(Refer to Figure 4-6k.)
The use of a distribution of normal design in this way is usually
done in an emergency. It is an unsafe method, as the secondary is
connected directly to the primary. For safety reasons, special attention
should be given when connecting or disconnecting such units.
