necessary for sensing temperature changes. These devices shall be mounted
on the transformer case in a suitable housing so that maintenance is
possible without removing the transformer cover or handling oil. Devices
26Q and 49 shall have three electrically independent contacts operating and
wired as follows:
a.
First set of contacts set to close at the manufacturer's
recommended setting and wired for starting [future] [first-stage]
forced-air-cooled fans.
b.
Second set of contacts set to close at the manufacturer's
recommended setting and wired to [start the second-stage
forced-air-cooling fans] [start pumps for forced-oil-cooling]
[alarm terminals in the transformer terminal cabinet] [alarm
terminals in the metal-clad switchgear].
c.
Third set of contacts set to close at the manufacturer's
recommended setting and wired to energize an auxiliary relay,
device 49X. The relay shall be mounted in the [transformer
terminal cabinet] [metal-clad switchgear]. Device 49X shall be
properly rated and equipped with not less than three normally open
and three normally closed sets of electrically independent
contacts. One set of contacts shall be wired to annunciate
excessive transformer temperature.
2.6.1.3
Neutral Grounding Resistor
**************************************************************************
NOTE: Time ratings greater than 10-seconds are
required only when the system is not taken off line
by a ground fault, but merely monitored.
**************************************************************************
The neutral grounding resistor assembly shall comply with IEEE Std 32and
shall be [factory-mounted on the associated transformer] [mounted adjacent
to the associated transformer] [mounted as indicated]. The assembly shall
meet the following:
a.
The resistor element shall be [stainless steel] [cast-iron] and
rated [_____] amperes for a [10-second] [1-minute] [10-minutes]
[extended time] duty.
b.
The resistor shall be installed in an aluminized screened or
expanded galvanized steel enclosure of the personnel safety type
and shall be provided with any necessary supports and mounting
hardware. The enclosure, including screening and support framing,
shall have two finish coats applied over a prepared substrate.
The color of the finish coats shall be the same as the color of
the associated transformer.
c.
A stress-relief terminator shall be provided and arranged to
permit the proper termination of the No. [_____] AWG, [_____] [5]
[15] kV shielded transformer neutral cable entering the enclosure
[from the [bottom] [top]] [as recommended by the manufacturer].
If the terminal bushing is external to the enclosure, the bushing
and terminal provisions shall be enclosed by a solid metal cable
box equipped with conduit fittings correctly sized for the conduit
required. An approved type and size of terminal lug shall also be
provided and arranged for the field termination of the No. 4/0 AWG
SECTION 16311A
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