the voltage rating and burden needed.
**************************************************************************
Voltage transformers shall have indicated ratios. Units shall have an
accuracy class rating of [_____]. Voltage transformers shall be of the
drawout type having current-limiting fuses in both primary and secondary
circuits. Mechanical interlocks shall prevent removal of fuses, unless the
associated voltage transformer is in a drawout position. Voltage
transformer compartments shall have hinged doors.
2.9
AUXILIARY SUBSTATION EQUIPMENT
2.9.1
Voltage Regulator
**************************************************************************
NOTE: Bypass arresters are normally standard
equipment. Incoming line arresters may not be
needed. Coordinate with manufacturer.
**************************************************************************
Voltage regulators shall comply with IEEE C57.15 and shall be of the
outdoor, self-cooled, 55/65 degrees C temperature rise, [single-phase]
[three-phase] station-type. Two single-phase units connected in open-delta
are not acceptable. Windings and the load-tap-changing mechanism shall be
mineral-oil-immersed. When operating under load, a regulator shall provide
plus and minus 10 percent automatic voltage regulation in approximately 5/8
percent steps, with 16 steps above and 16 steps below rated voltage.
Automatic control equipment shall provide Class 1 accuracy. Bypass surge
arresters shall be suitable for [a grounded] [an ungrounded] system and for
the associated regulator voltage. [Station] [Intermediate] class surge
arresters shall be mounted next to each incoming line bushing on a
regulator tank-mounted bracket and connected to a surge arrester ground
pad-mounted on the regulator tank.
2.9.1.1
Ratings
Ratings at 60 Hz shall be:
Maximum voltage.............................................[_____]
BIL.........................................................[_____]
Current.....................................................[_____]
2.9.1.2
Bypass and Isolation Switches
Switches shall be of the outdoor, stick-operated, single-pole,
single-throw, vertical-break type suitable for the indicted mounting. One
switch stick of adequate length shall be provided. Switches shall be of a
type designed to provide bypass of a single-phase regulator circuit by an
integral sequence which always occurs when each switch is opened or closed.
Each opening sequence shall initially bypass the single-phase regulator
circuit, then open the input and output circuits, and finally interrupt the
exciting current. Opening any single-phase regulator circuit shall not be
possible until after the bypass circuit is closed. Unless the voltage
regulator is equipped with integral line surge protective devices, [surge
protectors shall be mounted across terminals of each switch rated up to 25
kV.] [station-class surge arresters shall be provided to protect each phase
of 35 kV switches.] Ratings at 60 Hz shall be in accordance with IEEE
SECTION 16311A
Page 57
Previous Page
