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  • Product: Oil-immersed type Transformer
  • Rated capacity: 5~31500kVA
  • Frequency: 50/60Hz
  • Primary voltage: 11-36kV
  • Secondary voltage: 0.11~11kV



Transformers/reactors/intelligent integrated substations-Smart Energy for Better Life



1. One of the drafters of the National Standard Mine Flameproof Mobile Substations (GB/T 8286-xxxx ), which will replace the existing national standard (GB/T 8286-2005 ) and it was submitted for trial in Beijing.

2. +20 years experience R&D team, derived from 60 years of history transformer manufacturer in Changsha, Hunan, China since 1956.

3. Full range of transformer types with customized functions is available.

4. CE & ISO certificated.


Service Condition

A) Suitable for indoor or outdoor application

B) Air temperature: Maximum temperature: +40; Minimum temperature:-30

C) Humidity: Monthly average humidity 95%; Daily average humidity 90% .

D) Altitude above sea level: ≤1000m.

E) Max wind speed:35M/s

F) Ambient air not apparently polluted by corrosive and flammable gas, vapor etc.

G) No frequent violent shake



Below are the tests conducted by Varelen before delivery. Other tests required by clients can also be done accordingly.

Insulation resistance

Resistance of all windings

Check voltage ratio and vector group

No-load test at rated frequency and rated voltage

Impedance test

Withstand voltage testing

Induced over-voltage withstand test

Partial discharge measurement

Oil leakage test


Product Features:

1.Magnetic core

The three-limb iron core is made of oblique cut Grain-oriented, seven-step silicon steel lamination insulated

both sides, guaranteeing low losses and low noise. These values are even improved by laser treatment. It is

protected on the surface with a flash-proof varnish in order to prevent the sheet from corrosion and to reduce

the noise.

silicon steel


2. The winding

The winding as the centerpiece of the transformer must be especially protected – both against high electrical

stress due to external over voltages and against mechanical overloads by short circuits. Varelen transformers

are systematically designed to meet these requirements. The windings are made of copper or aluminum. Low-

voltage windings are made of strip or flat wire, and the high voltage windings are manufactured from round or

profile wire. (“diamond-dotted paper”) bonds the winding into a compact block while drying and increases the

short-circuit capacity additionally.



3.  The Tank Whether during transport or operation –the tank must be absolutely tight under mechanical stress. Preconditions to achieve this are constructional experience, the most modern calculation methods and high-quality welding work. Special attention is paid to corrosion protection. Pretreatment of the surface is processed by phosphating pickling, contributes to corrosion protection, just like multi-coating with preset drying times for each layer. On request, hot-dip galvanization provides for even better protection.