JST – Dry-Type Transformers

Home

JST

Dry-Type Transformers

Cast Resin Transformers

Cast epoxy resin transformers are highest on the evolutionary scale of transformer design and offer the best combination of electrical and mechanical performance factors. The robust structure achieved by casting the windings in a solid shell of epoxy provides mechanical strength unsurpassed by any other transformer available on the market. Cast resin transformers offer safety, environmental and sustainability goals set forth by many industries.

Benefits

Environmentally friendly
Superior dielectric properties
Robust structure allows protection against damage due to electrical faults and heavy electrical surges
Compact design
Low or no maintenance, which usually consists of wiping off accumulated dirt and dust
Self-extinguishing insulation system
Can be used anywhere in all different types of environments
Can be used up to voltage levels in the 35kV class, basic impulse levels (BIL) to 200kV and partial discharge levels to 10 pico-coulombs and below.
Overload capable and fans offered for extra cooling
Lower installation costs

Standard Features

Voltage: Up to 40.5KV
BIL: Up to 200kV
Ratings: Up to 45 MVA
Fan cooling available
Enclosure NEMA 1, 12, 3R, 4 & 4X
Rated power: 100kVA – 45MVA
High Voltage: 600V – 40kV
Typical High Voltages (kV): 2.3, 4.16, 8.7, 12.47,13.2, 13.8, 25, 34.5
Low Voltage: 0.208, 0.24, 0.48, 2.4, 4.16, 6.9, 12.47, 13.2, 13.8

Special Options

Forced Air Rating

133% increase using fans, maintaining the same temperature rise
150% increase using fans, but increasing the temperature rise for the FA (fan) rating
For example: 3000kVA (AA @ 80C temp rise) / 4500kVA (FA @ 115C temp rise)
Conductor material: aluminum (standard) or copper (optional)
Insulation Class: Class H (180C)
Primary taps: typically, 2 above and 2 below rated voltage, at 2.5% steps
95%, 97.5%, 100%, 102.5%, 105%
Custom designs available also, for example up to 10 taps, or 1.25% steps

VPI Transformers

VPI transformers are an excellent alternative in applications which call for an environmentally friendly, economical solution. They reduce flammability concerns, require less maintenance, and are less prone to contaminating the surrounding environment than liquid filled transformers avoiding the need for catch basins during construction.

Standard Features

Voltage: Up to 15 kV
BIL: Up to 110kV
Ratings: Up to 14.5 MVA
Enclosure NEMA 1, 12, 3R, 4 & 4X
Rated power: 100kVA – 14.5 MVA
High Voltage: 600V – 15kV
Typical High Voltages (kV): 2.3, 4.16, 8.7, 12.47,13.2, 13.8,15
Low Voltage: 0.208, 0.24, 0.48, 2.4, 4.16
High quality Class R (220C) impregnation varnish certified by UL

Special Options

Reactor
Up to 54 pulse transformer
Water cooled reactor

LV VPI Product Features

Capacity Range ≤1000kVA
Rated Voltage Range 3.3kV
Frequency 50Hz/60Hz
Structure VPI Dry type
Standards GB, IEC, ANSI/IEEE, UL etc.

Reactor Features

Capacity Range ≤10mH
Rated Voltage Range ≤ 3.3kV
Frequency 50Hz/60Hz
Structure VPI Dry type
Standards GB, IEC, ANSI/IEEE, UL etc.
Applications; Cranes, drives, propulsion etc.

Enclosure Options

Designed to meet all requirements of CSA and UL 50, JST offers a wide array of options when it comes to enclosures to meet your system needs.

NEMA 1

Primarily for indoor use. This general-purpose enclosure protects against falling dust and debris and offers a degree of protection from equipment contact. Its primary purpose is to minimize the risk to personnel of contact with live or hazardous parts.

NEMA 12

Primarily for indoor use. This general-purpose enclosure is similar to NEMA 1 but also provides some protection against dust, falling dirt, and dripping noncorrosive liquids. Meets drip, dust, and rust resistance tests.

NEMA 3R

Designed for both indoor and outdoor applications, the 3R enclosure provides protection against falling dirt and windblown dust, and weather hazards such as rain, sleet and snow, and is undamaged by the formation of ice.

NEMA 4/4X

Designed for indoor and outdoor applications. This watertight design meets the NEMA requirements for excluding at least 65 GPM of water from a one-inch nozzle delivered from a distance of not less than 10 feet for five minutes. Used outdoors on ship docks, in dairies, and in wastewater treatment plants and breweries. X (as in 4X) indicates additional corrosion resistance.

Note: NEMA 4/4X does not mean submersible.

NEMA 2

NEMA 2 enclosures are rated for indoor use and protects against accidental contact with device components, against ingress from solid objects and falling dirt and offer protection against light splashing and dripping water. NEMA 2 enclosures a great choice for indoor applications that require more protection than NEMA 1 at an affordable price.

Marine Enclosure

Designed for shipboard, platform and marine applications, the JST Marine Enclosure design enhances protection for your transformer in the most severe applications. This Marine Water Cooled/Hydro Cooler design is the perfect solution for your harshest application needs.