dry type power transformers - hammondsales.comthe transformer shall be dry-type. the transformer...

DRY TYPE POWER TRANSFORMERS

Aluminum, Core & Coil and Stubs-Up

Design Dry Type Power Transformers

Description and Applications ......................................... 242

Construction Features .................................................... 243

Standard Specifi cation Guide ......................................... 245

Power Transformer Quote Form ..................................... 246

Dry Type Power Transformer Selection ......................... 247

Aluminum, Stubs-Up Core & Coil Only Selection Table 248

Aluminum, Stubs-Up c/w Enclosure Selection Table ... 249

Optional Terminal Locations .......................................... 250

Options and Accessories ............................................... 251

SECTION 15

242Data subject to change without notice.

SECTION 15 DRY TYPE POWER TRANSFORMERSS

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© Hammond Power Solutions Inc.

APPLICATIONSWith the continued development in technology of materials, designs and manufacturing methods, the use of

dry type transformers is growing rapidly throughout North America.

Hammond Power Transformers are suitable for any commercial, industrial, manufacturing or production

process application. Power transformers, unit substation transformers, traction duty rectifi ers and cycloconverters

can be offered for a variety of environmental conditions and built to meet the most onerous duty, including MIL

standards.

In addition to conventional indoor applications, our dry units are located outdoors, on drilling platforms, in

network vaults and in every location where airborne contaminants pose a risk to electrical equipment.

This section of the catalog details only a small portion of our Power Transfomer product offering. Please

refer to our 6PWR Power Transformer catalog for complete product information and specifi cations on Hammond’s

line of power transformer products.

Data subject to change without notice.

SECTION 15 DRY TYPE POWER TRANSFORMERS

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CONSTRUCTION FEATURESHammond Power Solutions produces the most reliable, technologically advanced power transformers in the

market today.

This is as a result of continuing development in all phases of the design and manufacturing processes in

meeting the requirements of a broad range of customers and the most diffi cult applications. We now offer dry type

transformers with the largest KVA ratings and highest impulse voltage withstand level of any manufacturer.

Additionally, these transformers have demonstrated improved withstandability to short circuits and will

provide a life expectancy considerably in excess of current industry standards.

Core Construction

Hammond cores are manufactured from highest

quality non-ageing, cold rolled, grain oriented silicon

steel laminations. Cores are precision cut to close tol-

erances to eliminate burrs and improve performance.

They feature fully interleaved, stepped core construc-

tion and are available mitre cut for optimum energy

effi ciency.

Cores are carefully assembled and rigidly held

secure with structural steel clamps to minimize gaps.

The completed core is sealed in varnish or epoxy to

reduce noise emissions and prevent the ingress of

moisture.

Coil Construction

Coils are either layer (barrel), disc or section

wound to suit the voltage class. Typically, disc wound

coils are utilized at 8.7 kV class and higher, and par-

ticularly for more diffi cult applications. Available in alu-

minium or copper, windings are designed with wire or

foil conductors to minimize eddy losses and to provide

the highest short circuit strength.

Strip or foil wound low voltage coils are fully bal-

anced electrically to reduce axial short circuit forces.

Disc wound coils feature comb construction to

electrically balance voltage stresses over the full length

of the coil. Particular attention is paid to cooling these

windings as directed air fl ow is critical in this construc-

tion method.

All internal connections are braised or TIG or MIG

welded.



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Insulation

All Hammond dry type power transformers are

manufactured with class H, 220°C insulation materials

(180°C for copper). Only the best quality, high tem-

perature resistant materials are used including Nomex®

Aramid papers, silicone-coated fi berglass, Nomex®

sleeving, supersil duct sticks and pressure sensitive

glass tape. All materials meet or exceed UL, CSA and

IEC standards for use on dry type power transformers.

Construction Features con’t . . .

Core and Coil Assembly

As a completed assembly, the coils are held

rigidly in place between high compression insulators

clamped to the upper and lower core frames.

Coil and tap leads are secured fi rmly to the

transformer structure and terminal boards.

Low voltage bus bars are bolted to the upper or

lower core clamps with standoff insulators and quality

hardware with Lock Tight®, all to ensure the integrity of

the core and coil assembly.



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STANDARD SPECIFICATION GUIDE FOR DRY-TYPE POWER TRANSFORMERS

➥ The transformer shall be dry-type.

➥ The transformer core shall be manufactured from the highest quality non-aging, cold rolled, grain oriented silicon steel laminations using butt-lap stacked or step-lap mitered core construction.

➥ All transformer cores shall be sealed in varnish or epoxy to reduce noise emission and prevent rust.

➥ The conductors can be either copper or aluminum magnetic wire or strip foil.

➥ The primary and secondary coils shall be concentric wound.

➥ The high voltage windings shall be layer, or barrel wound up to 95 kV BIL. Disc windings are preferred at 95 kV BIL, and at voltages of 15 kV and higher whenever other design parameters allow.

➥ Low voltage windings shall be wire or strip wound and electrically fully balanced to minimize axial short circuit forces.

➥ Primary and Secondary coils are vacuum impregnated in either polyester resin or Thixotropic epoxy resin, and oven cured. Windings shall be vacuum impregnated a second time to ensure complete encapsulation.

➥ The encapsulation material should be selected to suit the application. For all standard dry type transformer applications installed in a conventional electrical room with or without a controlled environ-ment, polyester resin encapsulation shall be specifi ed. For any applications where transformers might be exposed to harsh environments or toxic airborne contaminants, thixotropic epoxy shall be required for a fi nal protective coat. Such environments include plants or factories that produce acidic or toxic fumes from plant processes and outdoor installations where temperature cycling or excessive humidity is a constant presence during normal operation. Additionally, salt air due to close proximity to salt water or any other manufacturing processes that result in virulent environments requires thixotropic epoxy impregnation.

➥ When thixotropic epoxy is specifi ed, it shall be fully compatible with that of the conductors and all insulating materials within the core and coil assembly. The coeffi cient of thermal expansion of the thixotropic epoxy shall be compatible with the operating conditions and any cyclical loading of the transformer.

➥ The transformer shall incorporate only the type of insulation material that fully bonds to the encapsulating compound when cured.

➥ Spacers between the primary and secondary coils, and all support beams and spacers, shall be made of the same type of heat resistant, non-aging fi berglass and resins used throughout the transformer.

➥ The transformer core and coils shall be manufactured as class H, 220° C insulation system, using only high temperature resistant insulation materials.

➥ The transformer shall be UL or CSA approved, or equivalent.

➥ The transformer shall be built to conform with IEEE-C57.12.01-1989 General Requirements for Dry-Type Distribution and Power Transformers.



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Please complete the following Specifi cation Guide/Quote Form for Hammond Power Transformers and fax to: Canada: (519) 822-9688 or U.S.: (608) 356-2080 or contact Hammond Quotations Department directly by calling: Canada: 1-888-798-8882 or U.S.: 1-800-537-0500.

Company Name: _______________________________________________ Date: ________________

Address: ____________________________________________________________________________

City: _________________________ State/Prov.: _____________ Zip/Postal: ____________

Contact Name: ______________________________ Phone #: __________________________

Fax Number: __________________________ E-Mail Address: ___________________________

Power Transformer Specification Guide and Quote Form

Quantity: _____________ Power Rating: _____________ kVA Phase: Single _______ Three Phase _______

Frequency: 50 Hz ____ 60 Hz ____ Other ____

Cooling: fan mounted provisions only ______ forced air cooling fans ______

Windings: Copper ______ Aluminum ______

Primary Volts: ____________V BIL (kv): __________

Connections: Delta _____ Wye-N _____

Terminations: Cable _____ Bus _____

Taps: FCAN ___________________ FCBN ___________________ RCBN ___________________

Secondary Volts:___________V BIL (kv):__________

Connections: Delta _____ Wye-N _____

Terminations: Cable _____ Bus _____

Taps: FCAN ___________________ FCBN ___________________ RCBN ___________________

Temp Rise: _________________°C

Insulation Class: ______________°C

Impedance: Standard ______ Other ______

Sound Level at No Load: ___________ dB

Impregnation: VPI Polyester ________ VPI Epoxy Resin ________

Approval: CSA _____ UL _____ Other ________

Enclosure: NEMA 1 ___ NEMA 3R ___ NEMA 4 ____ Pad Mount: Live Front____ Dead Front _____

Dimensions: _____”W X _____”H X _____”D

Paint: ANSI 61-Grey ______ Other _______

ACCESSORIES

Lightning Arrestors: Station ______________ Intermediate __________ Distribution ___________

Thermometers: No ______ Digital Type _______ Dial Type: 2 contact ____ 3 contact ____

Fan Kits: Yes ______ No ______ Provisions _______

Grounding Resistor: Yes _____ No _____

Grounding Bus: Yes _____ No _____

NGR Monitor: Yes _____ No _____

Seismic Zone: Yes _____ No _____

Seismic Restraints: Yes: Anti-vibration Pads_______ Vibration Isolators _______ No ____ Provisions ______

Ground Fault Relay: Yes _____ No _____

Nameplate: Aluminum _____ Stainless Steel _____

Power Source for Fans/Thermometers: From Transformer ____ From other source ____

Mining Duty: Yes _____ No _____

Kirk Key Interlock: No ____ Yes: Type D ____ Type VD ____

Current Transformer: No _____ Yes: HV ____ LV _____

Bushings: No ____ Yes: HV _____ LV _____

Electrostatic Shield: Yes _____ No_____

Duty Cycle: Yes _____ No _____

Space Heater: Yes _____ No _____

Mimic Bus: Symbol Req’d _____ Symbol Color _____ Width _____ Ht. of L.V. Mimic Bus _____ Ht. of H.V. Mimic Bus ______

Insulated Bus: No _____ Yes: HV _____ LV _____

Potential Transformer: No _____ Yes: HV ____ LV ____

PERFORMANCE REQUIREMENTS: (please complete the following) Customer P.O. # :

Quote # : ______________ Quoted By: __________________________ Date: _______________



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DRY TYPE POWER TRANSFORMER SELECTION

The tables on pages 248 and 249 list only a portion of the offering of Hammond three phase dry type power

transformer part number and dimensional specifi cations, and only for 150° C temperature rise units.

Tables 1 and Table 2 list aluminum units from 750 kVA to 3000 kVA in voltage classes from 1.2 kV to

15kV. Table 1 lists core and coil only “ stubs-up” design (with no enclosure). Table 2 lists core & coil “stubs-up

construction with Nema 1 ventilated enclosures.

For other kVA sizes, voltage classes or temperature rises, please refer to the Hammond “Dry Type Power

Transformer” Catalog (6PWR), or contact our quotations department.

For specifi cations on specialty transformers such as: dual HV windings, dual LV windings, rectifi er transform-

ers, traction duty transformers or cycloconverter transformers, please consult our quotations department.

Hammond’s line of outstanding power transformers

offers unparalleled reliability and performance for

the most diffi cult applications including mining,

excavation, transit, marine and cycloconvertion,

pulp and paper and utility. Any applications

where harmonics, short circuits, high intermittent

loads or exposed environmental hazards are

prevalent, or reduced electromagnetic emissions or

energy effi ciencies are required, Hammond power

transformers should be the one of choice.

Impulse Levels

The Transformer Group offers voltage

classes up to 46 kV and 200 kV BIL. The

unique design parameters utilizing disk

wound technology readily adapt to these

higher voltage classes. Our designs have

been subjected to all type tests per ANSI

and CSA specifi cations and have proven

their capability and reliability.

Special Applications



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W

HV

LV

D

HVLV

FRONT VIEW RIGHT SIDE VIEW

STUBS UP (CORE & COIL ONLY)

H

PLAN VIEW

HV

LV

HV

PLAN VIEW

LVHV

H

W


STUBS UP IN 'P' STYLE ENCLOSURE

HV

DD + 2

ALUMINUM, ‘STUBS-UP’ BUS DESIGN, CORE AND COIL ONLYSelection Table 1

Primary Minimum Core & Coil Approx. Dimensions Approx. kVA Volt Class Secondary Catalog Encl. Width Depth Height Weight (kV) Voltage Number No. (in) (in) (in) (lbs)

750 1.2 208Y/120 Consult Factory none 47 32 46 2950 750 2.5 & 5 208Y/120 Consult Factory none 47 37 47 3000 750 15 208Y/120 Consult Factory none 60 42 58 4200 1000 1.2 208Y/120 Consult Factory none 51 35 55 3500 1000 2.5 & 5 208Y/120 Consult Factory none 53 37 56 3900 1000 15 208Y/120 Consult Factory none 63 42 58 5100

1250 2.5 & 5 416Y/240 Consult Factory none 58 39 56 4500 1250 15 416Y/240 Consult Factory none 65 44 60 6000 1250 25 416Y/240 Consult Factory none 70 49 70 6800







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W

HV

H

LV

D + 3D

HV

LV


'J' STYLE ENCLOSURE

W

HV

LV

D + 3D

HV

LV


'UJ' STYLE ENCLOSURE

H

ALUMINUM, ‘STUBS-UP’ BUS DESIGN c/w ENCLOSURE Selection Table 2

Primary Minimum Enclosed Approx. Dimensions Approx. kVA Volt Class Secondary Catalog Encl. Width Depth Height Weight (kV) Voltage Number No. (in) (in) (in) (lbs)

750 1.2 208Y/120 Consult Factory UJ3 51.5 39 66 3450 750 2.5 & 5 208Y/120 Consult Factory J3 51.75 43.25 66 3500 750 15 208Y/120 Consult Factory P12 78 60 91.5 5300 1000 1.2 208Y/120 Consult Factory UJ6 64 40 68 4200 1000 2.5 & 5 208Y/120 Consult Factory J6 64 40 68 4500 1000 15 208Y/120 Consult Factory P12 78 60 91.5 6200

1250 2.5 & 5 416Y/240 Consult Factory J6 64 40 68 5200 1250 15 416Y/240 Consult Factory P12 78 60 91.5 7100 1250 25 416Y/240 Consult Factory P13 90 60 91.5 8000

1500 2.5 & 5 416Y/240 Consult Factory P3 66 54 72 6300 1500 15 416Y/240 Consult Factory P13 90 60 91.5 7800 1500 25 416Y/240 Consult Factory P13 90 60 91.5 9200 2000 2.5 & 5 416Y/240 Consult Factory P6 78 60 72 8100 2000 15 416Y/240 Consult Factory P13 90 60 91.5 9600 2000 25 416Y/240 Consult Factory P15 102 60 91.5 11000

2500 2.5 & 5 416Y/240 Consult Factory P12 78 60 91.5 8700 2500 15 416Y/240 Consult Factory P13 90 60 91.5 10600 2500 25 416Y/240 Consult Factory P20 114 72 110 12800 3000 2.5 & 5 416Y/240 Consult Factory P12 78 60 91.5 10300 3000 15 416Y/240 Consult Factory P20 114 72 110 12800 3000 25 416Y/240 Consult Factory P20 114 72 110 14800

Hammond Dry Type Power Transformers Terminations are also available in “Switchboard” designs.



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LV

HV

PLAN VIEW

LV

HVH

W


STRAIGHT BUSS TO END IN 'P' STYLE ENCLOSURE

LV

DD + 2

HV

LV

HV

PLAN VIEW

LV

HV

H

W


BUSS TO END IN 'P' STYLE ENCLOSURE

LV

DD + 2

HV

OPTIONAL TERMINAL LOCATIONSThe following optional terminal locations are available on all power transformers.



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OPTIONS AND ACCESSORIESThe following options/accessories are available on all Hammond Power Transformers:

2) Temperature monitoring devices, digital and

dial type, with and without contacts.

1) Neutral grounding resistors and monitors.

4) Ground Fault Relay3) Strip Heater

5) Anti-vibration Mountings:

anti-vibration pads, vibration isolators.



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Options and Accessories con’t ...

8) Nameplate: aluminum or stainless steel. 9) Seismic : Seismic snubbers, restraints or

provision.

6) Lightning Arrestors: station, intermediate,

distribution class.

7) Fans: Fans with or without control circuit, or

provision only for fan rating.

➧ Power source For Fans/Thermometers

➧ Secondary Breaker

➧ Bushings: A) high voltage B) low voltage

➧ Insulated Bus: A) high voltage B) low voltage

➧ Provisions for Cable Entry

➧ Ground Bus (1/4” X 2” Copper)

Other accessories available include:

➧ Mimic Bus

➧ Kirk Key Interlock

➧ Current and Potential Transformers

➧ Secondary metering: ammeter or voltmeter.

➧ Electrostatic Shield

dry type power transformers - hammondsales.comthe transformer shall be dry-type. the transformer...

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