DISTRIBUTOR HELMKE Transformers

for Industrial Applications

Power from 1 kVA to 10 MVA

Voltage from 400 V to 36 kV

For Catalogue

HELMKE Transformers

 

HELMKE Transformers

for Industrial Applications

Power from 1 kVA to 10 MVA

Voltage from 400 V to 36 kV

 

Table of contents

1. Product specification 3

1.1. Introducing the Helmke transformer product portfolio .......................................................................... 3

1.2. Principal product features .............................................................................................................................. 3

1.3. Applying standards and regulations ............................................................................................................ 4

1.4. Conditions of installation and operation .................................................................................................... 5

1.4.1. Climatic, environmental and fire protection .............................................................................................. 5

1.4.2. Installation altitude .......................................................................................................................................... 5

1.5. Design and manufacturing ............................................................................................................................. 6

1.5.1. Magnetic core .................................................................................................................................................... 6

1.5.2. Electrical windings ............................................................................................................................................ 6

1.5.3. Oil and oil tank .................................................................................................................................................. 7

1.5.4. Bushings .............................................................................................................................................................. 8

1.6. Accessories and instrumentation ................................................................................................................. 9

1.7. Product nameplate ........................................................................................................................................ 10

2. Sales and technical support 11

2.1. Equipment supply and engineering ............................................................................................................. 11

2.1.1. Product offerings in combination with transformers ............................................................................. 11

2.1.2. Service offerings in combination with transformers ............................................................................... 11

2.2. Product testing and quality control ............................................................................................................ 12

3. Product selection 14

3.1. Designation system ........................................................................................................................................ 14

3.2. Product selection tables ................................................................................................................................ 15

3.2.1. Oil immersed .................................................................................................................................................... 15

3.2.1. Dry type ............................................................................................................................................................. 17

4. Dimensional drawings 20

4.1.1. Oil immersed ................................................................................................................................................... 20

4.1.2. Dry type ........................................................................................................................................................... 20

Revisions:

All technical data, outputs, dimensions and weights stated in this catalogue are subject to change

without notice. Illustrations do not purpose to show constructional details.

 

3

1. Product specification

1.1. Introducing the Helmke transformer product portfolio

In synergy with the electric motors and drives portfolio, Helmke offers distribution and power

transformers to support industrial applications up to 10 MVA / 36 kV.

Offered transformer types:

§ Oil immersed

§ Dry type – cast resin

§ Dry type – open wound

Developed for:

§ Environmental safety

§ Custom-design and application flexibility

§ High energy efficiency and compactness

§ Protection against fire and harsh installation conditions

§ Low maintenance

§ High short circuit strength

Engineered as:

§ General purpose distribution and power transformers

§ Special purpose transformers, namely:

- Converter transformers

- Starter transformers

- Autotransformers

- Isolation transformers

Helmke transformers either engineered as single component or as part of a complete Power Drive

System (Helmke solutions®) come under Helmke single source supply and responsibility.

1.2. Principal product features

All transformer products are engineered according to the applying European and international technical

standards. State of the art production, testing and quality control processes guarantee for the

equipment safety and reliability.

Principal technical features as follows:

§ Executed according to EN / IEC 60076 and ANSI / IEEE C57.12 standards

§ Converter transformers additionally in compliance with EN / IEC 61378-1

§ Complying to the European commission Regulation (EU) 2019/1783 of the 1st October 2019

amending Regulation (EU) No 548/2014 on implementing Directive 2009/125/EC of the European

Parliament and of the Council with regard to small, medium and large power transformers,

respectively standard DIN / EN 50588-1 (Medium power transformers 50 Hz, with highest voltage

for equipment not exceeding 36 kV - Part 1: General requirements)

§ Magnetic lamination from high permeability and low hysteresis cold rolled grain oriented silicon steel

according to EN / IEC 60404-8-7 for low specific losses and reduced noise emissions

§ Magnetic core assembled with step-lapped joints in simple overlapping arrangement between the

yoke and limb sections of the magnetic core to further allow for reduced core leakage reactance,

resp. no load current and no load core losses as well as improved noise emissions.

§ LV and HV windings made from copper or aluminum electrolytic conductors

4

§ In oil immersed, dry type open wound or cast resin execution depending on power-level, application

and customer specification

§ Insulation materials up to thermal class H

§ Partial-discharge-free design and execution of windings

§ Customizable auxiliaries and instrumentation

§ Build-in design features for premium climatic, environmental and fire protection

§ Customizable enclosures for IP 21 up to IP 42 degree of protection. Higher IP ratings on request, in

conjunction with fully containerized solutions

1.3. Applying standards and regulations

Helmke transformers comply with relevant EN / IEC and IEEE standards and regulations, especially as

defined in Table 1.

Furthermore, Helmke transformers, in cast resin, oil immersed or dry type execution, are non-polluting

to the environment and designed to meet the highest energy efficiency European standards (Table 2 on

the product conformity to European directives).

Customized products on the basis of area or customer-specific standards and specifications can be

engineered and produced on request.

Standard Content

EN / IEC 60076-1 Power transformers - Part 1: General

EN / IEC 60076-2

Power transformers – Part. 2: Temperature rise for liquid-immersed

transformers

EN / IEC 60076-3

Power transformers – Part. 3: Insulation levels, dielectric test and external

clearances in air

EN / IEC 60076-5 Power transformers – Part. 5: Ability to withstand short circuit

EN / IEC 60076-7 Power transformers - Part 7: Loading guide for mineral-oil-immersed power

transformers

EN / IEC 60076-10 Power transformers – Part. 10: Determination of sound levels

EN / IEC 60076-11

Power transformers - Part 11: Dry-type transformers

EN / IEC 60076-12 Power transformers - Part 12: Loading guide for dry-type power transformers

EN / IEC 61378-1 Converter transformers – Part 1: Transformers for industrial applications

DIN / EN 50588-1

Medium power transformers 50 Hz, with highest voltage for equipment not

exceeding 36 kV - Part 1: General requirements

EN / IEC 60085 Electrical insulation - Thermal evaluation and designation

EN / IEC 60529 Degree of protection provided by enclosures (IP code)

EN / IEC 60270 High-voltage test techniques - Partial discharge measurements

IEEE C57.12.01

IEEE® Standard for General Requirements for Dry-Type Distribution and

Power Transformers

IEEE C57.12.91 IEEE® Standard Test Code for Dry-Type Distribution and Power Transformers

Table 1. Product standards

European directive Content

2009/125/EC directive on eco-design requirements for energy-related products

2011/65/EU directive on Hazardous Substances (RoHS 2)

Table 2. Product conformity to European directives

5

1.4. Conditions of installation and operation

1.4.1. Climatic, environmental and fire protection

Steel components and enclosures of transformers are standard protected against corrosion with

protection level C2 acc. to EN ISO 12944-2. Different types of paint and painting methods are further

available against different corrosion levels of C2, C3, C4, C5-I and up to C5-M (marine and off-shore

applications) depending on customer specification.

Custom-design flexibility allows meeting special customer needs and applications as further detailed

under each of the different transformer types offered.

1.4.1.1. Oil immersed transformers

The transformers are suitable for indoor and outdoor installation. Both the surfaces treatment and the

electrical design in terms of clearances and creepage lengths qualify them for humid ambient

conditions and for operation in areas polluted with electrical conducting dust.

Application-specific oil selection can extend their storage, transportation and operation in areas up to

and below –25 °C and qualify them for application in controlled (increased safety) areas.

1.4.1.2. Dry type - cast resin transformers

Helmke cast resin transformers are designed to meet climatic (C), environmental (E) and fire behavior

classes (F) according to EN / IEC 60076-11.

The transformers feature a fire resistant and self-extinguishing design of the highest fire protection

class F1 acc. to EN / IEC 60076-11. Climatic and environmental protection classes C2, E2 delivered by

default are suitable for the majority of indoor industrial applications. Higher protection classes as per

EN /IEC 60076-11 along with higher IP ratings for both indoor and outdoor installations can be further

engineered and executed on request.

An overview on admissible climatic, environmental and fire behavior conditions during transportation,

storage and operation of cast resin transformers is given in the following table.

Class Designation Definition

Climatic (C) C2 The transformer is suitable for operation, transport and

storage at ambient temperatures down to -25 °C

Environmental (E) E2 The transformer can withstand frequent condensation or light

pollution or combination of both

Fire behavior (F) F1 Transformers subject to fire hazard, featuring restricted

flammability and minimum emission of toxic substances and

opaque smokes

Table 3. Environmental, climatic and fire protection specifications for Helmke cast resin transformers

1.4.1.3. Dry type – open wound transformers

Dry type transformers feature an open-type execution, thus an IP00 degree of protection.

Nevertheless, in combination with customizable enclosures or in fully containerized turn-key execution,

dry type transformers can be executed both for indoor and outdoor installation.

Customized protection of enclosures against corrosion and chemical attack can be provided through

various coating methods on request.

1.4.2. Installation altitude

All Helmke transformers are suitable for operation at altitudes of up to 1000 m above sea level. For site

altitudes above 1000 m please apply to Helmke technical sales for customer-specific product

engineering, as derating factors apply.

6

1.5. Design and manufacturing

1.5.1. Magnetic core

The functional purpose of the magnetic core is to provide a low reluctance path for the magnetic flux

linking primary and secondary windings. The magnetic circuit in a transformer is made of steel

lamination sheets basically composing of iron powder and approximately 3% silicon as the main alloy

element.

To achieve the goal of premium efficiency, meeting and surpassing applying standards, Helmke uses

high-quality, low-hysteresis Cold-Rolled Grain-Oriented steel sheet (CRGO) transformer laminations

complying with IEC 60404-8-7 standard. Both sides of the lamination are coated with a thin film of

inorganic, oil- and corrosion-resistant coating, offering a surface insulation resistivity of at least 100

Ωmm2 for the minimization of eddy current loss (measurement according to ASTM A717).

As most of the losses in transformer cores arise on the area of the yoke-limb joints, Helmke

transformers have the ends of the core yokes and limbs mitered and stacked together by a simple

overlapping arrangement (step-lapped miter joints). This arrangement allows for the gradual and

smooth transfer of magnetic flux from vertical to horizontal direction and visa-versa, a feature that

reduces leakage fluxes and local magnetic induction values, ultimately lowering the transformer corner

losses. Further advantages include the reduction of noise emissions due to magnetostriction as well as

increased structural stiffness to support higher short circuit ratings.

Depending on the type and power rating, Helmke magnetic cores may be equipped with oil/air cooling

channels and oil/air guide elements for efficient heat evacuation. The feature reduces hot spots thus

raising the gravimetric and volumetric power density of the transformer design, respectively its

compactness and cost effectiveness.

Laminations for Helmke transformer cores are cut and assembled in automated stamping and stacking

tables respectively.

1.5.2. Electrical windings

The windings consist of current-carrying conductors and are wound over the core limbs. Helmke

transformers are made of high-conductivity materials, either high purity electrolytic copper or

aluminum conductors. The exact material selection depends on several application parameters but

mainly on the power transformer rating and load profile (respectively transformer type). The definition

of winding system and materials is thus the result of a techno-commercial optimization process which

runs under each customer inquiry.

1.5.2.1. Oil immersed

The winding conductors are typically made of high purity (99,9%) Electrolytic Tough Pitch copper (Cu-

ETP). Windings can be formed as continuous or interleaved discs, arranged in a simple or multiple

helixes, each according to rating and specification. Winding cooling is optimized by the incorporation of

oil-flow channels and guide elements in the design of the winding and the winding fixing method.

Tapping is provided on the high voltage side. Taps are controlled either by means of off load or on load

tap changers, the latter provided solely from well known European suppliers.

Prior tank assembly and subsequent filling of oil under vacuum conditions, the windings are dried in

order to reach the exact dimensions and avoid successive inelastic failure due to operational stress. All

windings are firmly braced on multiple support points. Helmke oil immersed transformers offer

practically partial-discharge-free performance, as the quantity of voids and air in the windings and oil

tank is monitored and controlled throughout the production process.

1.5.2.2. Dry type - cast resin

The low voltage windings are made of copper or aluminum foil material. Neighboring turns are

insulated with multiple layers of thermal class H insulation material. The windings are multi-layered and

of helical type, a feature which provides the highest stability on mechanical stress as well as reduced

copper losses due to the minimization of the skin effect on current carrying conductors.

7

After assembly on the core, the low voltage winding is impregnated with epoxy resin. The exact resin

and insulating material is selected according to the rated thermal class. Thermal class H is standard

specified for cast resin transformers. Customer specification can be met on request.

The high voltage windings are either made of enamel copper or aluminum round wires or strips, mainly

depending on the transformer current rating. The windings are typically multi-layered and feature

either a helical or disk-like form. Inter-turn and inter-layer insulation is made of high quality insulation

materials, thermal class H as standard or as per customer specification. Symmetrical tapping is

provided on the high voltage side, in order to avoid unbalance of ampere-turns.

The high voltage windings are cast under vacuum in epoxy resin. During the casting process, critical

parameters such as resign pressure, flow and temperature are monitored and computer controlled for

the purpose of quality assurance.

Finished winding assemblies feature a fully encapsulated and hermetically sealed design, offering the

ultimate protection against dust pollution and chemical attack. Furthermore, expert selection of

impregnating varnishes and resins, as the result of long technical experience and know-how, renders

transformers with superior fire withstand capability and minimized environmental footprint. Finally,

Helmke cast resin windings feature practically partial-discharge-free behavior with apparent charge

values measured according to EN / IEC 60270 below 10 pC.

1.5.2.3. Dry type – open wound

Transformers rated for thermal class H, are equipped with low voltage windings made from electrolytic

copper plates. Thermal class H insulation material is interleaved between the winding turns. Use of thin

plate material instead of the traditional helix windings renders the transformer core significantly more

resilient against electro-dynamic stresses, especially the high forces developed under short circuit

conditions. The high voltage windings, depending on power and voltage rating of the transformer, are

wound either over a single or multiple layers, as either single or multiple, series connected coils of helical

or disk shape. In each case, thermal class H enamel wires and NOMEX® insulation is utilized as

standard. Uniform air cooling as well as bracing of both low voltage and high voltage windings is

provided through adequate axial and radial spacing of different winding layers and between turns by

means of multiple, accurately produced spacers. Furthermore, low voltage and high voltage windings

are insulated against each other as well as against the core by fiberglass material. All windings are

firmly braced on multiple support points. The windings are finally dried out in oven and then

impregnated under vacuum with class H resin. This enables accurate and robust mechanical execution

along with an almost partial-discharge-free electrical performance.

Transformers rated for thermal class F feature similar design, based typically on the use of either

electrolytic copper or aluminum conductors of rectangular or circular cross section. Insulating

components between low voltage and high voltage windings as well as against the ground walls of the

core are made from fiberglass material while turn insulation is realized with thermal class F material of

polyester basis. Final windings treatment includes also in this case drying and impregnation under

vacuum with respective thermal class F resins.

1.5.3. Oil and oil tank

The standard tank design for oil immersed transformers is utilizing fins and radiators for heat

evacuation. Depending on power rating, application and customer specification, forced cooling may be

applied by means of auxiliary axial fans.

Transformer tanks are coated internally with oil resistant and externally with corrosion resistant paints.

The standard corrosion protection level C2 acc. to EN ISO 12944-2 can be increased on demand up to

level C5 for outdoors installation on and offshore.

Transformer oils meet relevant international standards and European directives. Vegetable

biodegradable oil FR3 is typically used to promote executions with minimum environmental footprint.

Upon demand filling can be performed with insulating silicon oil. Customer-specific oils can be

considered on request.

8

1.5.4. Bushings

Porcelain bushings are used according to DIN / EN / ISO and ANSI standards. Special designs based f.i.

on the use of certified Euromold® bushings, plugs or other customer-specific systems can be engineered

and provided on request.

9

1.6. Accessories and instrumentation

1.6.1.1. Cast resin and dry type transformers

§ Standard accessories

- lifting lugs

- transportation skid with bidirectional wheels

§ Optional accessories

- temperature sensors (PT 100 or dial type thermometers)

- temperature control device

- forced ventilation

- surge arrestors kit

- anti-vibration pads kit

- auxiliary terminal box (offering a centralized connection point for all auxiliaries installed)

1.6.1.2. Oil immersed transformers

§ Standard accessories

- lifting lugs

- off load tap changer

- oil level indicator on the oil conservator

- oil filling and drain flanges

- air vent valve

- Buchholz (gas detector) relay

- DGPT2 protection relay for hermetically sealed transformers, detecting

§ gas discharge or drop of the dielectric level (1 contact)

§ internal pressure (1 contact)

§ dielectric temperature (2 contacts)

- dial type thermometer with two sets of electrical contacts (alarm/trip)

- mounting plug (thermowell) for additional temperature detector

- mounting plug for dehydrating breather with installed dehydrating breather

- bidirectional heavy duty metal wheels

§ Optional accessories

- on load tap changer

- PT 100 temperature sensors (winding/oil)

- temperature control device

- forced ventilation

- surge arrestors kit

- anti-vibration pads kit

- main terminal box for low voltage and/or high voltage side - both customizable on request

- auxiliary terminal box (offering a centralized connection point for all auxiliaries installed)

10

1.7. Product nameplate

Transformer nameplates are executed in stainless steel and robustly riveted on the transformer frame.

The standard name plate is issued in English language and provides technical information and rated

values according to EN / IEC 60076-1.

The standard nameplate format, as per following figure can be expanded on demand to include

additional, customer-specific information or language.

Figure 1. Standard format of Helmke transformer nameplate (dimensions in mm)

11

2. Sales and technical support

2.1. Equipment supply and engineering

Helmke continuously updates and expands its product portfolio in line to the increasing market demand

for sophisticated process control and automation as well as maximum energy efficiency for power

driven equipment in industrial applications.

This enables Helmke to offer a wide range of complete Power Drive Systems (PDSs) to Original

Equipment Manufacturers (OEMs) and end-customers, over a broad range of application and market

sectors around the globe.

2.1.1. Product offerings in combination with transformers

§ In combination with general and special purpose distribution and power transformers of all types:

- Mounting and transportation skids

- Protection enclosures (steel cabinets up to IP 42)

- Fully containerized transformer stations

§ In combination with converter transformers executed acc. to EN / IEC 61378-1:

- Static power converters comprising of multiple rectifier groups (6, 12, 24 pulse)

- Complete PDSs comprising of power converters and motors

§ In combination with special purpose autotransformers and starting transformers:

- Squirrel cage induction motors with customer-specific starting characteristics

- Slip-ring induction motors for high starting torque applications

§ In combination with special purpose isolating transformers:

- Power converters ready for operation in unearthed electrical systems (IT grids), with integrated

ground-fault monitoring and protection

Under the complete PDS scope, Helmke is your single source supplier for reliable motor and drives

technology, from the tendering phase up to the successful project completion.

2.1.2. Service offerings in combination with transformers

The application engineers of Helmke have deep experience in planning and engineering of tailor made

PDSs, from the HV distribution board, to the transformer station and up to the individual load

consumers. Offered technical services as follows:

§ Project planning: From initial concept, to system commissioning and up to the end of the product life

cycle

§ Engineering Procurement Commissioning (EPC) project management: Execution and monitoring of

project plan - status reporting

§ Engineering of complete PDSs, including full definition of electromechanical interfaces to existing

infrastructure and equipment

§ Experimental validation of PDS performance on the testing field: realistic equipment testing under

environmental (thermal/vibration) and electromechanical conditions emulating steady-state,

transient or faulty states of the end-application

§ Engineering of power, distribution and special purpose transformers as well as complete PDSs with

turn-key transformer stations for severe climatic conditions or hazardous environments

§ Delivery and commissioning under the sole responsibility of Helmke

Either a standard or tailor-made transformer or a complete PDS including general and special purpose

(f.i. converter) transformers, they all come under the same EPC project support as well as Helmke

guarantee.

Helmke is your single source supplier for reliable motor and drives technology, from the tendering phase

up to the successful project completion.

12

2.2. Product testing and quality control

All Helmke transformers undergo routine testing according to EN / IEC 60076 for the test items

specified in Table 4. Type testing can be offered on request according to the same.

Test item Type of test

(R = Routine)

(T = Type)

Visual control R

Measurement of insulation resistance R

Measurement of winding resistance R

Measurement of voltage ratio and check of phase sequence R

Measurement of short circuit impedance and load losses R

Measurement of no load-loss and current R

Separate-source AC withstand test R

Induced AC withstand voltage test R

Temperature rise test T

Lightning impulse withstand test T

Measurement of sound level T

Short-circuit test T

Measurement of zero-sequence impedance T

Partial discharge measurement T

Table 4. List of test items for transformers

Furthermore, special and R&D tests to validate the environmental, climatic and fire protection classes

of dry type cast resin transformers according to IEC 60076-11 can be offered. Those special tests are

executed in cooperation with accredited testing laboratories within Europe.

All testing fields of the Helmke group are capable of performing transformer routine and type tests.

Overview of the Helmke group testing facilities as follows:

§ Site Pulversheim (France, near Mulhouse). Two load testing fields for low / high voltage machines

and drive systems:

- Power of max. 6 MW and max. 1.5 MW respectively

- Adjustable three phase 50-60 Hz AC voltage supplies 0 – 0,4 / 0,7 / 2,3 / 4,16 / 6,3 / 11 / 13,8 /

16,8 / 20 / 33 kV and 0 – 0,5 / 1 / 3,5 / 7,5 / 14 kV respectively

§ Site Sarstedt (Germany, near Hannover). No-load testing field for low / high voltage machines and

drives

- Installed power of voltage supplies 315 kW

- Adjustable three phase 50-60 Hz AC voltage supplies 0–0,69 / 0–2 /0–5 / 0–7 / 0–10 / 0–12 kV

Overview of the testing services offered:

§ Type and routine tests of transformers and complete PDSs according to national and international

standards

§ Factory acceptance tests in the presence of the customer according to common standards and

customer-specific quality specification

§ Prototype and pre-series tests of single components or complete PDSs (integration of customer

specific measurement systems if required)

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§ R&D testing and experimental validation for full PDSs: Vibration and sound pressure level

measurement, testing under emulated operational transients and faults

(a)

(b) (c)

Figure 2. Testing and commissioning of Helmke transformers

(a) System string test – Full load acceptance test, witnessed by the end-customer.

System comprising of converter transformer (3500 kVA, 13,8 / 2x3x1,92 kV, 14 t ), power electronics

converter and asynchronous motor

(b) Converter transformer type test (5070 kVA, 10 kV / 4x1,9 kV, 16 t)

(c) Step-up transformer commissioning (8600 kVA, 11 kV / 20 kV / 33 kV, 14 t)

For further information on the Helmke testing services please read the Helmke testing field brochure

under https://Helmke-testing.com/.

14

3. Product selection

3.1. Designation system

Transformers of this catalogue follow the following designation system:

(a)

(b)

Figure 3. Helmke designation system for transformers

(a) general purpose and special purpose transformers except from starter transformers

(b) starter transformers

15

3.2. Product selection tables

3.2.1. Oil immersed

Reference data for general purpose, step-down 17,5 and 24 kV / 400 V, 50 Hz oil immersed

transformers in the range 50 to 2500 kVA as follows. The transformers are executed in three versions,

reflecting different efficiency classes and respective sizes and weights under the same rating. Outline

dimensions apply according to the dimensional drawings of chapter 4.

For higher power rating and application specific engineering please apply directly to Helmke technical

sales.

Design version number

Rated power

No-load losses (Po)

Short circuit losses

(Psc) at 75 °C

Efficiency (n)

Load 4/4

Efficiency (n)

Load 3/4

Short circuit

impendence (Z)

Dimensions Weight

cos(φ)

= 1

cos(φ)

= 0,9

cos(φ)

= 1

cos(φ)

= 0,9 a b h e d oil total

[kVA] [W] [W] [%] [%] [%] [%] [%] [mm] [mm] [mm] [mm] [mm] [kg] [kg]

03

50 150 850 98,03 97,82 98,35 98,17 4 1120 450 1100 520 100 110 480

100 250 1400 98,37 98,19 98,63 98,48 4 1170 560 1180 520 100 150 680

160 360 1850 98,63 98,48 98,84 98,71 4 1210 590 1200 520 100 180 850

200 430 2170 98,71 98,57 98,91 98,79 4 1250 620 1350 520 100 200 1000

250 520 2600 98,76 98,63 98,95 98,83 4 1285 670 1450 520 100 250 1160

315 610 3050 98,85 98,72 99,02 98,91 4 1300 700 1500 520 100 290 1350

400 740 3650 98,91 98,79 99,07 98,97 4 1350 750 1550 670 150 330 1600

500 800 4500 98,95 98,83 99,11 99,02 4 1420 850 1620 670 150 360 1900

630 900 5600 98,97 98,86 99,15 99,05 6 1470 920 1680 670 150 450 2200

800 1100 7200 98,97 98,86 99,14 99,05 6 1500 980 1750 670 150 550 2600

1000 1300 9000 98,98 98,86 99,15 99,06 6 1510 1050 1850 820 150 600 2900

1250 1600 10600 99,03 98,92 99,19 99,11 6 1800 1150 1900 820 150 690 3400

1600 2000 13000 99,07 98,96 99,22 99,14 6 2150 1250 1950 820 150 780 4000

2000 2400 16000 99,08 98,98 99,24 99,16 6 2250 1350 2150 1070 200 900 4700

2500 2900 21000 99,05 98,94 99,22 99,13 6 2450 1460 2200 1070 200 1050 5500

16

Design version number

Rated power

No-load losses (Po)

Short circuit losses

(Psc) at 75 °C

Efficiency (n)

Load 4/4

Efficiency (n)

Load 3/4

Short circuit

impendence (Z)

Dimensions Weight

cos(φ)

= 1

cos(φ)

= 0,9

cos(φ)

= 1

cos(φ)

= 0,9 a b h e d oil total

[kVA] [W] [W] [%] [%] [%] [%] [%] [mm] [mm] [mm] [mm] [mm] [kg] [kg]

02

50 190 1100 97,48 97,21 97,88 97,65 4 1120 470 1100 520 100 100 440

100 320 1750 97,97 97,75 98,29 98,11 4 1170 590 1150 520 100 150 650

160 460 2350 98,27 98,08 98,53 98,37 4 1200 640 1200 520 100 170 810

200 550 2800 98,35 98,17 98,61 98,45 4 1250 680 1250 520 100 200 950

250 650 3250 98,46 98,29 98,69 98,55 4 1250 700 1350 520 100 230 1100

315 790 4000 98,51 98,33 98,72 98,59 4 1300 750 1420 520 100 260 1280

400 930 4600 98,63 98,48 98,84 98,71 4 1350 780 1500 670 150 300 1500

500 1100 5500 98,69 98,55 98,89 98,77 4 1480 820 1600 670 150 350 1800

630 1300 6500 98,77 98,64 98,96 98,84 6 1610 870 1650 670 150 410 2000

800 1500 8500 98,76 98,63 98,96 98,85 6 1700 950 1750 670 150 520 2400

1000 1700 10500 98,79 98,66 98,99 98,88 6 1800 1030 1850 820 150 570 2800

1250 2100 13500 98,76 98,63 98,97 98,86 6 1950 1150 1900 820 150 650 3200

1600 2600 17000 98,78 98,65 98,99 98,88 6 2130 1315 2060 820 150 770 3850

2000 3200 22000 98,75 98,61 98,97 98,85 6 2300 1450 2150 1070 200 900 4500

2500 3800 26500 98,82 98,67 99,01 98,91 6 2350 1450 2270 1070 200 980 5000

01

50 380 1200 96,93 96,61 97,26 96,96 4 1090 490 980 520 100 100 420

100 460 2100 97,51 97,23 97,85 97,62 4 1100 560 1080 520 100 130 600

160 540 2950 97,86 97,63 98,21 98,01 4 1210 580 1150 520 100 160 750

200 630 3500 97,97 97,75 98,29 98,11 4 1250 630 1150 520 100 180 810

250 780 4100 98,08 97,87 98,38 98,21 4 1350 640 1350 520 100 200 950

315 900 4950 98,17 97,97 98,46 98,29 4 1390 700 1400 520 100 230 1100

400 1100 6500 98,13 97,93 98,43 98,26 4 1450 810 1450 670 150 250 1300

500 1300 7800 98,21 98,01 98,51 98,34 4 1480 830 1500 670 150 300 1450

630 1500 9000 98,36 98,18 98,63 98,48 4 1560 900 1550 670 150 330 1700

800 1700 11000 98,43 98,26 98,72 98,56 5 1670 970 1600 670 150 410 2000

1000 2000 12800 98,54 98,38 98,78 98,65 6 1780 1000 1680 820 150 480 2350

1250 2400 14200 98,68 98,54 98,91 98,78 6 1880 1100 1900 820 150 600 2950

1600 2700 18500 98,69 98,54 98,91 98,82 6 2000 1160 1950 820 150 680 3300

2000 3200 25000 98,62 98,45 98,86 98,73 6 2050 1200 2000 1070 200 770 3800

2500 4000 30000 98,65 98,51 98,89 98,77 6 2150 1300 2200 1070 200 900 4500

17

3.2.2. Dry type

The following table gives basic rating data for step down cast resin transformers. Secondary voltage

400 V / 50 Hz. Derating factors may apply in the case of open wound transformers.

For application-specific product selection and engineering please apply directly to Helmke technical

sales.

High voltage

Rated power

No-load losses (Po)

Short circuit losses (Psc)

at 75 °C

Efficiency (n)

Load 4/4

Efficiency (n)

Load 3/4

Short circuit

impendence (Z)

Inrush current (Ir/In)

Dimensions

cos(φ)

= 1

cos(φ)

= 0,9

cos(φ)

= 1

cos(φ)

= 0,9 a b h e d

[kV] [kVA] [W] [W] [%] [%] [%] [%] [%] [mm] [mm] [mm] [mm] [mm] [kg]

7,2

100 500 1900 97,42 97,12 97,76 97,44 6 9,5 1090 650 1100 520 100 580

160 600 2950 97,57 97,31 97,96 97,74 6 9,5 1100 650 1175 520 100 690

200 700 3400 97,75 97,51 98,11 97,92 6 9,5 1120 650 1185 520 100 810

250 750 3950 97,94 97,72 98,28 98,09 6 9,5 1130 650 1200 520 100 910

315 910 4800 98,01 97,79 98,33 98,15 6 9,5 1160 650 1320 520 100 1050

400 1000 5450 98,22 98,02 98,52 98,35 6 9 1210 800 1500 670 150 1240

500 1250 6000 98,41 98,23 98,66 98,51 6 9 1300 800 1560 670 150 1400

630 1450 7300 98,47 98,31 98,72 98,57 6 9 1380 800 1600 670 150 1650

800 1700 8700 98,56 98,41 98,81 98,67 6 9 1430 800 1670 670 150 1850

1000 2000 9900 98,69 98,54 98,92 98,77 6 9 1500 950 1760 820 150 2200

1250 2250 12000 98,74 98,61 98,95 98,83 6 8,5 1550 950 1850 820 150 2650

1600 2700 13700 98,87 98,74 99,05 98,95 6 8,5 1690 950 1900 820 150 3300

2000 3000 17000 98,89 98,77 99,08 98,98 6 8,5 1660 1200 2300 1070 200 3800

2500 3350 20000 98,96 98,85 99,14 99,05 6 8 1850 1200 2350 1070 200 4400

3150 4000 22000 99,08 98,98 99,24 99,15 7 7,5 1900 1200 2450 1070 200 5400

12

100 530 1850 97,44 97,16 97,77 97,53 6 10 1100 650 1100 520 100 590

160 630 2900 97,63 97,34 97,97 97,75 6 10 1100 650 1175 520 100 690

200 730 3360 97,76 97,52 98,11 97,91 6 10 1150 650 1185 520 100 840

250 770 3900 97,95 97,73 98,28 98,09 6 10 1170 650 1200 520 100 940

315 950 4700 98,03 97,82 98,34 98,16 6 10 1200 650 1320 520 100 1080

400 1050 5300 98,25 98,06 98,53 98,37 6 9,5 1250 800 1500 670 150 1250

500 1300 5950 98,41 98,23 98,65 98,5 6 9,5 1350 800 1560 670 150 1420

630 1550 7200 98,47 98,31 98,71 98,56 6 9,5 1400 800 1600 670 150 1680

800 1800 8600 98,57 98,41 98,79 98,66 6 9,5 1470 800 1670 670 150 1900

1000 2100 9800 98,69 98,54 98,89 98,77 6 9,5 1530 950 1760 820 150 2250

1250 2400 12000 98,73 98,59 98,93 98,81 6 9 1590 950 1850 820 150 2700

1600 2950 13200 98,88 98,75 99,05 98,94 6 9 1740 950 1900 820 150 3450

2000 3200 16500 98,91 98,79 99,09 98,99 6 9 1700 1200 2300 1070 200 3900

2500 3600 19500 98,97 98,86 99,15 99,05 6 8,5 1790 1200 2350 1070 200 4500

3150 4300 21800 99,08 98,98 99,23 99,14 7 8 1940 1200 2450 1070 200 5500

Weight

18

High voltage

Rated power

No-load losses (Po)

Short circuit losses (Psc)

at 75 °C

Efficiency (n)

Load 4/4

Efficiency (n)

Load 3/4

Short circuit

impendence (Z)

Inrush current (Ir/In)

Dimensions

cos(φ)

= 1

cos(φ)

= 0,9

cos(φ)

= 1

cos(φ)

= 0,9 a b h e d

[kV] [kVA] [W] [W] [%] [%] [%] [%] [%] [mm] [mm] [mm] [mm] [mm] [kg]

18

100 550 1800 97,51 97,24 97,81 97,61 6 10 1100 700 1100 520 100 600

160 650 2800 97,68 97,43 98,02 97,81 6 10 1100 750 1175 520 100 700

200 750 3250 97,77 97,53 98,11 97,91 6 10 1155 760 1185 520 100 850

250 800 3800 97,96 97,74 98,28 98,09 6 10 1170 770 1200 520 100 950

315 1000 4600 98,07 97,86 98,36 98,18 6 10 1200 780 1320 520 100 1100

400 1100 5200 98,26 98,08 98,54 98,39 6 9,5 1260 860 1500 670 150 1280

500 1350 5800 98,41 98,24 98,65 98,51 6 9,5 1350 870 1560 670 150 1450

630 1600 7000 98,48 98,32 98,71 98,57 6 9,5 1410 880 1600 670 150 1700

800 1850 8300 98,62 98,45 98,81 98,68 6 9,5 1470 890 1670 670 150 1950

1000 2200 9500 98,72 98,57 98,91 98,79 6 9 1530 980 1760 820 150 2300

1250 2500 11500 98,77 98,64 98,96 98,85 6 9 1590 990 1850 820 150 2750

1600 3000 13000 98,88 98,76 99,05 98,95 6 9 1740 1000 1900 820 150 3400

2000 3300 16200 98,92 98,81 99,09 98,99 6 9 1710 1200 2300 1070 200 3950

2500 3700 19000 99,01 98,89 99,16 99,07 6 8,5 1800 1200 2350 1070 200 4600

3150 4400 21300 99,11 99,02 99,23 99,15 7 8 1950 1200 2450 1070 200 5600

24

100 550 1800 97,51 97,24 97,81 97,61 6 10 1130 740 1175 520 100 630

160 650 2800 97,68 97,43 90,02 97,81 6 10 1170 750 1175 520 100 750

200 750 3250 97,77 97,53 98,11 97,91 6 10 1185 820 1200 520 100 900

250 800 3800 97,96 97,74 98,28 98,09 6 10 1215 830 1220 520 100 1000

315 1000 4600 98,07 97,86 98,36 98,18 6 10 1260 830 1300 520 100 1150

400 1100 5200 98,26 98,08 98,54 98,39 6 9,5 1290 910 1490 670 150 1300

500 1300 6200 98,36 98,19 98,62 98,47 6 9,5 1350 920 1550 670 150 1550

630 1650 6950 98,49 98,33 98,71 98,57 6 9,5 1470 940 1600 670 150 1800

800 1850 8300 98,61 98,45 98,81 98,68 6 9,5 1500 950 1670 670 150 2100

1000 2200 9500 98,72 98,57 98,91 98,79 6 9,5 1590 1040 1800 820 150 2500

1250 2600 11000 98,81 98,67 98,98 98,87 6 9 1650 1050 1850 820 150 2950

1600 3150 13000 98,91 98,79 99,06 98,96 6 9 1830 1080 1930 820 150 3700

2000 3500 16200 98,94 98,79 99,08 98,98 6 9 1770 1200 2300 1070 200 4100

2500 4000 18500 99,01 98,92 99,16 99,07 6 8,5 1860 1200 2350 1070 200 4900

3150 4600 21000 99,19 99,13 99,31 99,23 7 8 1950 1200 2450 1070 200 5600

36

100 900 2800 96,06 95,64 96,53 96,15 5 9,5 1400 930 1250 520 100 950

160 1000 3150 97,21 96,91 97,54 97,27 6 9,5 1450 940 1100 520 100 1100

200 1050 3300 97,63 97,37 97,92 97,69 6 9,5 1480 940 1200 520 100 1200

250 1150 3500 98,12 97,78 98,24 98,05 6 9,5 1500 950 1250 520 100 1310

315 1300 3800 98,25 98,06 98,45 98,28 6 9,5 1560 960 1300 520 100 1480

400 1500 4200 98,45 98,28 98,62 98,46 6 9,5 1575 1040 1450 670 150 1730

500 1650 4900 98,57 98,41 98,74 98,61 6 9,5 1650 1100 1500 670 150 2000

630 2000 6000 98,62 98,47 98,78 98,65 6 9 1770 1120 1550 670 150 2300

800 2500 6600 98,77 98,63 98,89 98,77 6 9 1830 1150 1600 670 150 2750

1000 3000 7900 98,81 98,68 98,94 98,82 6 9 1880 1150 1700 820 150 3100

1250 3400 9300 98,89 98,76 99,01 98,91 6 9 1920 1200 1800 820 150 3500

1600 4000 10900 98,98 98,86 99,09 98,99 6 9 2000 1200 2200 820 150 4150

Weight

19

High voltage

Rated power

No-load losses (Po)

Short circuit losses (Psc)

at 75 °C

Efficiency (n)

Load 4/4

Efficiency (n)

Load 3/4

Short circuit

impendence (Z)

Inrush current (Ir/In)

Dimensions

cos(φ)

= 1

cos(φ)

= 0,9

cos(φ)

= 1

cos(φ)

= 0,9 a b h e d

[kV] [kVA] [W] [W] [%] [%] [%] [%] [%] [mm] [mm] [mm] [mm] [mm] [kg]

2000 4900 13100 99,01 98,91 99,12 99,02 6 8,5 2100 1300 2300 1070 200 4900

2500 5500 16200 99,05 98,94 99,16 99,06 6,5 7,5 2190 1300 2350 1070 200 5900

3150 5900 20200 99,09 98,99 99,21 99,12 8 7 2340 1350 2670 1070 200 7100

Weight

20

4. Dimensional drawings

4.1.1. Oil immersed

Figure 4. Oil immersed transformers. Outline drawing with basic reference dimensions

4.1.2. Dry type

Figure 5. Dry type transformers. Outline drawing with basic reference dimensions

Notes