handle mechanism. The cross sectional area of the braid shall be
equivalent to a No. 4 AWG conductor, minimum.
2.6
SUBSTATION EQUIPMENT
**************************************************************************
NOTE: Make selections in this paragraph and in
paragraph STATION ARRANGEMENT as appropriate for the
installation. For this specification an articulated
primary unit substation has both high-voltage and
low-voltage sections mechanically coupled to the
transformer. A primary unit substation has only the
low-voltage section mechanically coupled to the
transformer. For any given installation, only
paragraph Primary Unit Substation or Substation
Transformer or Articulate Primary Unit Substation
will apply. For voltages through 34.5 kV, the
primary switch/breaker should be
mechanically-coupled or bus-duct-connected to the
transformer primary. For 46 kV and above, the
primary circuit breaker/switch should be cable-or
aerial-bus-connected to the transformer primary. In
general, the transformer secondary should be
mechanically-coupled or bus-duct-connected to the
secondary switchgear through and including 34.5 kV.
**************************************************************************
The installation shall be [of the switching station] [of the primary unit
substation] [of the substation transformer] [an articulated primary unit
substation of the [radial] [distributed-network] [spot-network]
[secondary-selective] [duplex]] type. [The initial capacity of the
substation is based on the [55/65 degrees C] [self-cooled] [single-stage
cooled] [two-stage cooled] [transformer capacity shown]]. The number of
outgoing [lines] [distribution feeders] shall be as shown. Outgoing
circuits shall be three-phase [three-wire] [four-wire] type [with [a bare]
[an insulated] neutral] having a voltage rating of [_____] kV
phase-to-phase. The insulated neutral shall have insulation rated not less
than 1000 volts. Outgoing circuit equipment shall be rated for a nominal
voltage class of [_____] kV and shall have a BIL of not less than [_____]
kV. Outgoing circuits shall leave the station [aerially] [underground] [in
cable trays].
2.6.1
**************************************************************************
NOTE: Coordinate with paragraph Specific Unit
Requirements.
Since some POWER TRANSFORMER manufacturers prefer
the use of forced-oil-cooling over
forced-air-cooling for the second stage, allow
either option. Specify an oil preservation system
for self-cooled capacities greater than 5000 kVA.
Coordinate load-tap-changing type with Voltage
Regulator section of paragraph AUXILIARY SUBSTATION
EQUIPMENT.
**************************************************************************
The power transformer shall comply with IEEE C57.12.00 and shall be of the
SECTION 16311A
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