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6 Read and translate Text 4:

Text 4
Secondary Distribution

Branching from the main feeder are laterals, also referred to in the
industry as taps or branches. The laterals may be three-phase, two-
phase (two phases of the three-phase feeder with a neutral), or
single-phase (one phase from the single phase feeder and a
neutral). The laterals are usually protected with fuses so that
faulted laterals do not cause interruption at the feeder level.

Standard secondary voltage levels are
 120/240 single phase
 120/208 3 phase
 277/480 3 phase

The 120/240 configuration is obtained from the low-side of a
HV/240 volt transformer, where HV is the rated voltage on the
high voltage side, and the 240 is the rated voltage on the low
voltage side. Then a center tap is connected to the low voltage
winding and grounded along with the low side of the primary
winding. This provides three wires on the low voltage side. One is
+120V, one is -120V, and one (the center tap) is 0. Thus, two are
“hot,” one is ground (neutral). The 240V connection is obtained by
connecting across the two hot wires. The 120V connection is
obtained by connecting from either hot wire to the neutral wire.
Some other essential equipment not yet mentioned includes:
 Lightning arrestors
 Insulators
 Wood poles

7 Make the following phrases complete.
1. The subtransmission system is also sometimes designated
to indicate … .
2. Circuit breakers, … are protection devices.
3. If the load were to increase, the far-end voltage would drop
to … .
4. The primary distribution system consists of … .

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