How power transformer be manufactured, tested & delivered? (Photos tell you)

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Below we are sharing photos of 15/20 MVA 46 / 6.3 KV Power Transformers, to explain how Daelim manufacture, test and deliver power transformers.

Pad-mounted Transformer

We can provide you single phase and three phase pad mounted transformer

Dry-type Transformer

Type:Cast resin; Rated Capacity: Up to 25MVA; Rated Voltage: Up to 36KV;

Pole Transformer

TypeCSP type Frequency: 50/60Hz; Rated Power: 5~167kva

Oil immersed transformer

Frequency: 50/60Hz Rated voltage:10kv, 20kv,30kv Rated Power: 400~2500kva

Table of Content

Power transformer standards

As project requirement, transformers are manufactured as per below standards: 

IEC – 60076

ANSI C57.12.10

IEC 60137

IEC – 60214

IEC 60044.1

IEC – 60156

IEC – 60439

IEC – 60502

ASTM D 3487

IEEE 693- 2005


Power transformer specification

1-Type :                                                        3 phases Power Transformer

2-Rated Power MVA                                       15000/20000

3-Rated Voltages( At No Load) kV/kV               46/6.3

4-Rated Frequency  Hz                                    60

5-Type of tap changer on HV side                    ON-load

6-Number of taps on HV                                 17(±8×1.875%)

7-Insulation Level

-HV (Bil/AC) kV                                              250 /85
-LV (Bil/AC) kV                                               60/25

8-Vector Group Symbol                                   Dyn1

9-Cooling Method                                           ONAN/ONAF

10-Max.Winding/Oil Temperature Rises ℃        55/50

11-Type of tank                                             Barrel type

12-No Load Losses at rated Voltage Ration kW  20.8

13-Load Losses 

-at 75 °C based 15MVA, at nominal tap kW       69.2 

14-Impedence Voltage

-at 75 °C, based 15MVA / 20 MVA, at nominal tap %  8.0 / 10.67

15-No load Current at rated voltage ratio %       0.4

16-Approximate Weights

a)Total Weight  kg                                          29200

b) Oil Weight    kg                                          6100

c) Active part    kg                                          14100

d) Transport Weight(without oil) kg                   22000


HV: Oil/Air Condenser Bushing                          yes

HV-N: Oil/Air Condenser Bushing                       yes

LV: Oil/Air      Bushing                                       yes

18- Manufacturing Standards                            ANSI C57.12.10


Power transformer accessories and secondary line

Transformer fans

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MR OLTC on load tap changer & mechanism

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Secondary wiring – current transformer wiring

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IP 55 control box

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Explosion-proof pipe

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Fiber optic temperature measurement

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Power transformer testing

The FAT tests of the power transformers including below items:

1  Dielectric tests

2 Measurement of Voltage Ratio and Vector Group

3 Measurement of Winding Resistance

4 Separate-Source Power-Frequency Voltage Withstand Test

5 Measurement of bushing capacitance and Dielectric Dissipation Factor

6 Lighting Impulse Voltage Withstand Test

7  Induced Voltage Withstand and Partial Discharge Test

8 Measurement of No-load Losses and No-load Current

9  Measurement of Impedance Voltage and Load losses

10  Measurement of Zero-Sequence Impedance

11  Sealed Test

12  Temperature Rise Test

13  Measurement of Noise Level

14  Measurement of the winding frequency spectrum response curve

15  Current transformer test

16  OLTC tests

17 Polarity test

Some recording photos, we provide live broadcasts for clients.

Let’s know learn more about the AUSTRALIA CUSTOMER

Lighting impulse test

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Power frequency test

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Power transformer delivery

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When packing, our professional transformer forwarder reinforces the goods at port.

Customized power transformer

Daelim is a professional power transformer manufacturer. Power transformers are exported to the United States, Canada, Mexico, Australia, Ecuador, Chile and other North and South America regions, and many substations and mobile substations have been established.

Professional technical team and nearly 20 years of international market experience enable Daelim to customize various types of power transformers. Daelim’s transformer brand is Daelim Belefic, which is already quite influential in North and South America.

If you have any related questions, please tell Daelim without reservation, and the Dalelim team will give you the best transformer solution.

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About Daelim

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About Bin Dong

Hello, I am Bin, General manager of Daelim which is a leading transformer manufacturer. If you have problems when you are looking for the equipment, what you need to do is tell us.

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DAELIM BELEFIC transformer provide various choose for domestic or foreign brand accessories, which can save your cost and provide most reliable performance.

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We did more than 110 projects each year, and many project cases in overseas countries, especially for South America area. Due to the close contact with the region, we can provide complete installation, commissioning and after-sales service.


DAELIM BELEFIC team have rich experience for overseas transformer tender projects. When we received the tender documents, our solid and professional team always can give the quick responds and solutions to your project. We have confidence to help us our customer to win any project.

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