Three Phase Oil Immersed Pad Mount Dead Front Transformer

SIlverstone Electric liquid-filled three-phase pad-mounted transformers are an excellent choice for any commercial or industrial underground distribution system. Typical applications include manufacturing facilities, refineries, office buildings, schools, hospitals, restaurants, warehouses, and retail stores. All Howard Industries transformers are designed, built, and tested in an ISO-9001 certified facility in accordance with applicable industry standards.

All designs feature fully enclosed tamper resistant terminal compartments and can be supplied with dead-front or live-front construction, for loop or radial feed applications.

Ratings

Standard Features
• Meets or exceeds current IEEE, NEMA, RUS, and DOE standards as applicable
• Full compliance with ANSI C57.12.28 enclosure integrity standards
• Externally clamped universal high-voltage bushing wells
(three for radial feed operation or six for loop feed operation)
• Externally clamped low-voltage bushings with threaded stud for full-load
Current through 1400 Amps, or externally clamped one-piece
NEMA spade bushings for full-load current above 1400 Amps
• Front panel accessory mounting brackets
• Removable neutral ground strap in low-voltage compartment
(for wye connected low-voltage ratings only)
• Removable high-voltage/low-voltage neutral link, internally mounted
And accessible through tamper-resistant hand hole
(Wye-Wye units only)
• Lifting provisions
• Jacking/rolling provisions
• Removable terminal compartment and bottom sill and removable doors
With stainless steel hinges
• Bolted hand hole on oil compartment top with tamper-resistant security cover
• Three-point door latching system with recessed interlocking pentahead
Security bolt and padlock provision
• Tank ground provisions
• Mild steel tank and terminal compartment construction
• Mild steel high-voltage/low-voltage compartment barrier

Optional Features
• Loadbreak high-voltage bushing inserts or externally clamped integral
(one piece) high voltage bushings
• Low-voltage connectors, including various screw-on or slip-on types
• Externally operable nonloadbreak high-voltage tap switch with one of
The following tap ranges: Four 2.5% taps above normal;
Or four 2.5% taps below normal;
Or two 2.5% taps above and two 2.5% taps below normal;
Or taps at 13800/13200/12870/ 12540 for transformers with a
Nominal high voltage rating of 14400 (may not be available
In combination with dual high-voltage switch)
• Externally operable dual high-voltage switch (may not be available
In combination with highvoltage tap switch)
• Fault indicators or fault indicator mounting provisions only
• Internal expulsion fuses, alone or in combination with internal
Backup current limiting fuses
• Draw-out expulsion fuses with isolation links, alone or in
Combination with internal backup current limiting fuses
• Draw-out full-range current limiting fuses in dry-well canisters;
With or without interlocking loadbreak switch
• Internal full-range current limiting fuses
• MOV surge arresters, including under-oil or elbow
• Drip shields for use with draw-out expulsion fuses
• Externally operable two-position or four-position high-voltage loadbreak switch
• Internal low-voltage circuit breaker with external operating handle,
Or external molded case low-voltage circuit breakers
• High capacity pressure relief device mounted on tank cover
• Drain valve with sampling device
• Amorphous Metal Core
• Total stainless steel or hybrid (mild steel/ stainless steel) construction
• Ester-based insulation fluid