Choose your transformer

Used or surplus

If you need a transformer right away or if you’re looking for an economical option, check out our inventory list to see all available used and surplus transformers.

Oil-immersed Distribution Transformers

Our standard BTB oil-immersed distribution transformers are manufactured up to 72,5 kV and 3150 kVA and meet the requirements of international standards (IEC). The transformers also comply with the EU’s directive for Eco Design.

If you need higher power ratings, please see the power transformers. If you’re looking for special application transformers, you can find more information here.

When you see a BTB Transformer rating plate, you can trust that the transformer meets our high standards and is produced by one of our trusted partners. However, if you’re looking for a specific brand transformer, just let us know. We have contacts for all the major producers and can find you exactly what you need.

The following specifications are valid for all standard sizes:

Frequency: 50 Hz
Connection: Dyn11
Ambient temperature: -40 / +40°C
Standards: IEC 60076
Temperature rise: 60 / 65 K
Bushing: Porcelain or plugin
Winding material: Al or Cu
Insulation class: A
Energy losses: ECO design or other classes

11 kV series Tier2

Primary voltage: 11 kV ±2x2,5 %
Secondary voltage: 400 V
Insulation level: 12 / 28 / 75 kV

The primary and secondary voltages are also available in the following ratios:

10 kV ±2×2,5 % / 400 V
10,5 kV ±2×2,5 % / 410 V
11 kV ±2×2,5 % / 420 V

Please specify the voltage ratio, quantities and accessories when sending us a message or request.

Please scroll sideways for more information. < >

[kVA] Uk [%] Po [W] Pk 75 °C [W] Weight [kg] Dimensions [mm]
A B C D
50 4 81 750 370 1 250 700 1 030 TBA
100 4 130 1 250 530 1 275 730 1 175 TBA
160 4 189 1 750 730 1 210 780 1 220 TBA
200 4 225 2 015 790 1 410 750 1 365 TBA
315 6 324 2 800 1 020 1 480 780 1 445 TBA
400 6 387 3 250 1810 1280 890 1540 TBA
500 6 459 3 900 1360 1 495 910 1 800 TBA
630 6 540 4 600 1 680 1 410 860 1 650 TBA
800 6 585 6 000 1 950 1 695 1 000 1 780 TBA
1 000 6 693 7 600 2 290 1 750 1 040 1 805 TBA
1 250 6 855 9 500 3 030 1 105 1 465 2 025 TBA
1 600 6 1 080 12 000 3 430 1 830 1 080 1 945 TBA
2 000 6 1 305 15 000 4 050 1 935 1 120 2 105 TBA
2 500 6 1 575 18 500 4 520 1940 1 230 2255 TBA
3 150 6 1 980 23 000 TBA TBA TBA TBA TBA

22 kV series Tier2

Primary voltage: 22 kV ±2x2,5 %
Secondary voltage: 400 V
Insulation level: 24 / 50 / 125 kV

The primary and secondary voltages are also available in the following ratios:

20 kV ±2×2,5 % / 400 V
20,5 kV ±2×2,5 % / 410 V
21 kV ±2×2,5 % / 420 V

Please specify the voltage ratio, quantities and accessories when sending us a message or request.

Please scroll sideways for more information. < >

[kVA] Uk [%] Po [W] Pk 75 °C [W] Weight [kg] Dimensions [mm]
A B C D
50 4 81 750 370 1 240 700 1 060 TBA
100 4 130 1 250 530 760 1035 1 220 TBA
160 4 189 1 750 730 1 210 780 1 220 TBA
200 4 225 2 015 790 1 435 750 1 420 TBA
315 6 270 2 350 1 020 1515 790 1 495 TBA
400 6 387 3 250 1810 1280 890 1540 TBA
500 6 459 3 900 1360 1590 960 1 605 TBA
630 6 540 4 600 1 680 1 410 860 1 650 TBA
800 6 585 6 000 1 950 1 820 1060 1 800 TBA
1 000 6 693 7 600 2290 1 880 1090 1 735 TBA
1 250 6 855 9 500 3 030 1 820 1 060 1940 TBA
1 600 6 1 080 12 000 3 430 1 795 1 030 2 145 TBA
2 000 6 1 305 15 000 4 050 1 855 1 030 2 260 TBA
2 500 6 1 575 18 500 4 520 1985 1 230 2250 TBA
3 150 6 1 980 23 000 TBA 2220 1190 2680 TBA

Custom design

If you need a custom design transformer, we are flexible to meet various requirements. Custom designs are made to order and handled as individual projects to ensure that all specific requirements are met.

With a custom design, we can offer the following special features:

  • Dual primary voltage
  • Various connections and phase displacement
  • Temperature rise according to site conditions
  • Increased insulation level with increased withstand to lightning and overvoltage peaks
  • Rigid tank design with bolt-on or welded cooling radiators and oil expansion tank
  • Cable termination boxes
  • Voltage regulation with bolted links for more failsafe operation
  • Voltage regulation with motorized on-load tap changer
  • Different types of cooling liquids
  • Custom sizes for spaces with dimensional restrictions

Power Transformers

We can supply power transformers up to 525 kV and 1000 MVA that meet the requirements of international standards (IEC). Design according to other national standards (ANSI, BS, etc.) is available upon request.

Standard design

Our standard design power transformers have top-cover mounted bushings without cable boxes and a rigid radiator tank with a bolted cover. Upon request, the transformer can be made with side-mounted bushings and a welded cover.

Our transformers are equipped with an off-circuit tap-changer or an on-load tap-changer (OLTC) and as standard ONAN cooling.

The level of accessories and monitoring equipment is limited to such types that can be retrofitted to the standard design.

The energy losses are standardized to normal and low losses. Other specific requirements in terms of energy losses can be achieved with a custom design.

Custom Design

The customization process covers everything from both electrical and mechanical design parameters to the level of accessories and instrumentation. This gives us full freedom to meet special requirements, such as impedance, level of losses, and noise levels. It also gives us the possibility to fit the transformers into places with space restrictions.

Custom designs are made to order and handled as individual projects to ensure that all specific requirements are met.

With a custom design, we can offer the following special features:

  • Dual primary voltage
  • ONAF or OFWF cooling
  • Cable termination boxes
  • Various connections and phase displacement
  • Temperature rise according to site conditions
  • Special surface treatment for harsh conditions
  • Special design to meet existing or restricted dimensions
  • Voltage regulation with bolted links for more failsafe operation
  • Voltage regulation with motorized on-load tap changer (OLTC)
  • Adapted for mobile substations
  • Special industrial design

Dry-type Transformers

Our BTB dry-type transformers are manufactured up to 52 kV and 25 000 kVA and meet the requirements of international standards (IEC). The transformers also comply with the EU’s directive for Eco Design.

Design according to other national standards (ANSI, BS, etc.) is available upon request.

When you see a BTB Transformer rating plate, you can trust that the transformer meets our high standards and is produced by one of our trusted partners. However, if you’re looking for a specific brand transformer, just let us know. We have contacts for all the major producers and can find you exactly what you need.

Our BTB dry-type transformers can be produced as open wound, vacuum pressure impregnated (VPI) or cast-resin.

The following specifications are valid for all standard sizes:

Frequency: 50 Hz
Connection: Dyn11
Ambient temperature: -25 / +40°C
Standards: IEC 60076-11
Temperature rise: 100 / 100 K
Basic concept (HV/LV): Cast-resin / VPI
Classification: E2-C2-F1
Winding material: Al / Al
Insulation class: F / F
Energy losses: ECO design or other classes
Standard accessories: - 3 pcs PT100 sensors connected to an IP54 terminal box
- Bi-directional wheels

11 kV series Tier2

Primary voltage: 11 kV ±2x2,5 %
Secondary voltage: 400 V
Insulation level: 12 / 28 / 75 kV

The primary and secondary voltages are also available in the following ratios:

10 kV ±2×2,5 % / 400 V
10,5 kV ±2×2,5 % / 410 V
11 kV ±2×2,5 % / 420 V

Please specify the voltage ratio, quantities and accessories when sending us a message or request.

Please scroll sideways for more information. < >

[kVA] Uk [%] Po [W] Pk 120 °C [W] Io [%] Noise levels [dB] Dimensions [mm] Weight IP00 [kg] Enclosure
LpA LwA A B C D
100 6 252 1800 1,3 39 51 1170 600 1175 520 770 1
160 6 360 2600 1,9 41 53 1260 600 1285 520 950 1
250 6 468 3400 1,5 44 56 1240 600 1445 520 1200 2
400 6 675 4500 1,3 47 59 1350 750 1475 670 1500 2
630 6 990 7100 1,2 49 61 1420 850 1605 670 1850 2
800 6 1170 8000 1,1 51 63 1560 850 1795 670 2450 2
1 000 6 1395 9000 1 52 64 1550 1000 1845 820 2750 3
1 250 6 1620 11000 1 54 66 1570 1000 2165 820 3330 3
1 600 6 1980 13000 0,9 55 67 1640 1000 2175 820 3800 3
2 000 6 2340 16000 0,9 57 69 1830 1310 2185 1070 4600 3
2 500 6 2790 19000 0,8 58 70 1860 1310 2490 1070 5450 5
3 150 6 3420 22000 0,7 61 73 2110 1310 2530 1070 7100 5

22 kV series Tier2

Primary voltage: 22 kV ±2x2,5%
Secondary voltage: 400 V
Insulation level: 24/50/125 kV

The primary and secondary voltages are also available in the following ratios:

20 kV ±2×2,5 % / 400 V
20,5 kV ±2×2,5 % / 410 V
21 kV ±2×2,5 % / 420 V

Please specify the voltage ratio, quantities and accessories when sending us a message or request.

Please scroll sideways for more information. < >

[kVA] Uk [%] Po [W] Pk 120 °C [W] Io [%] Noise levels [dB] Dimensions [mm] Weight IP00 [kg] Enclosure
LpA LwA A B C D
100 6 252 1800 2,2 39 51 1150 600 1250 520 1100 1
160 6 360 2600 1,9 41 53 1300 600 1290 520 1050 1
250 6 468 3400 1,5 44 56 1430 600 1505 520 1500 2
400 6 675 4500 1,3 47 59 1470 750 1446 670 1800 2
630 6 990 7100 1,2 49 61 1520 850 1580 670 2200 2
800 6 1170 8000 1,1 51 63 1570 850 1805 670 2650 3
1 000 6 1395 9000 1 52 64 1690 1000 1930 820 3200 3
1 250 6 1620 11000 1 54 66 1700 1000 2160 820 3600 3
1 600 6 1980 13000 0,9 55 67 1800 1000 2225 820 4250 4
2 000 6 2340 16000 0,9 57 69 1860 1310 2310 1070 4950 4
2 500 6 2790 19000 0,8 58 70 1910 1310 2550 1070 5800 5
3 150 6 3420 22000 0,7 61 73 2070 1310 2580 1070 7200 5
Enclosure (optional)

Standard design IP21 / 23 / 31. Special design up to IP68.

Dimensions in mm (LxWxH) * Weight in kg Distance between wheels Standard color
Type 1 1850x1100x1580 160 Same as measurement D RAL 7035
Type 2 2050x1150x1980 210
Type 3 2300x1250x2520 270
Type 4 2500x1310x2660 300
Type 5 2750x1400x2960 360

* Height is excluding wheels and potential lifting lugs

Custom design

If you need a custom design transformer, we are flexible to meet various requirements. Custom designs are made to order and handled as individual projects to ensure that all specific requirements are met.

With a custom design, we can offer the following special features:

  • Dual primary or secondary voltages
  • Design also suitable for special applications such as; converter, rectifier, furnace, motor starting, windmill, marine etc.
  • Various connections and phase displacements
  • Temperature rise according to site conditions
  • Increased insulation level with increased withstand to lightning and overvoltage peaks
  • Enclosures according to customer requirements with various levels of ingress protection (IP-class) up to IP68
  • Surface treatment for harsh conditions
  • Cooling fans for ANAF operation with an increased power rating
  • Voltage regulation with motorized on-load tap changer
  • Higher insulation class (e.g. H/H)

Special Application Transformers

Designing transformers for special applications requires experience and knowhow.

Confidently equipped with both, we design and manufacture transformers that fit your operation no matter the application.

COMPENSATING EQUIPMENT

If you need equipment for compensating earth fault currents, reactive power, or a combination of both, we have standard and special solutions for both centralized and distributed compensation.

CENTRALIZED COMPENSATION

Earthing Transformer with Arc Suppression Coil (Petersen Coil)

Shunt Reactor (with Petersen coil duty)

DISTRIBUTED COMPENSATION

The compensation of earth fault currents in overhead lines can be done by centralized compensation at the electrical substations. The additional use of distributed compensation, either as pole-mounted or ground-mounted units, has certain advantages for compensating large underground cable networks. For example, the rated power of the distributed compensation units is generally very small compared to the power of the centralized compensating equipment.

BTB Treactor

Shunt Reactor (with Petersen coil duty)

OTHER SPECIAL APPLICATIONS

Earthing Transformers & Reactors

Multi-voltage Transformers

Rectifier & Converter Transformers

Starting Transformers

Furnace Transformers

Traction Transformers

Booster Transformers