BEST A.S. provides its customers with all services regarding their transformers from installation, field tests, commissioning and future maintenance, to repair and modernization of faulty transformers with its half a century of transformer production experience and resources.

Our Customer Services Department, equipped with state of the art testing devices and assembly equipment, was established with its staff having high-level engineering experience gained from years of background to create solutions for all your problems in the energy industry.

Replacement Parts

BEST A.S. has stock management system and material storage infrastructures for the purposes of monitoring and supplying materials that should be supplied in advance in accordance with project-oriented production plan. Inventory codes pertaining to used parts or accessories are monitored during or after the project and therefore possible future replacement and spare part demands are rapidly met.


On-site repair works are conducted with state of the art materials and equipment, and the transformers are put into operation as soon as possible.

Our transformer repair services are as follows;

> Coil replacement
> Core replacement
> Repair or replacement of mechanical accessories
> Conservator replacement
> Drying in kerosene vapor spraying vacuum furnaces
> Isolation renewal

All issues notified to us through our Customer Services Team are evaluated by BEST A.S., while our qualified and professional repair-maintenance and service team is 24/7 ready to effectively and rapidly respond upon receiving a customer complaint.

Maintenance and On-Site Services

In line with the demands of our customers, we periodically perform all necessary maintenance and obn-site services of available on-site transformers pursuant to operating and maintenance instructions.

In addition, operating and maintenance instructions for all kinds of transformers are provided to customers.

On-site services that we provide during maintenance are as follows;

> Assembly and Starting

Transformers are dispatched with complete or partial assembly according to their dimensions and transportation conditions.

Particularly big power transformers are dispatched with their insulators, conservator, radiators and other small accessories disassembled. Many transformers are dispatched without oil and filled with nitrogen gas. Transformer oils are transported in specially processed barrels or tanks.

Weights and dimensions of big power transformers require very diligent planning in terms of assembly and transportation. BEST A.S. has vast experience in transportation of all kinds of transformers to various locations throughout the world and their on-site assembly. It guarantees speed and efficiency in assembly and commissioning works with its qualified engineers and high-quality equipment.

On-site services that we provide for newly installed transformers are as follows;

> Insulation resistance test (Megger)
> Conversion Ratio Test
> Windy Resistance Test
> Dobble AC isolation test
> Tightness under pressure test
> Discharge and filling of transformer oil under vacuum
> Dielectric Strength Test of Oil
> Power Factor of Oil
> Measurement of water in oil
> Gas analysis of oil
> Functional tests of protection elements
> General checking of transformers
> Elimination of oil leaks and provision of permanent solutions
> Maintenance of low voltage and high voltage insulators, improvement of connections and replacement of insulators when necessary
> Functional tests of protection elements and replacement of defective elements with modernized protection elements
> Electrical tests of transformers
> Sampling of transformer oil and oil analysis
> Discharge of transformer oil on-site with modernized systems
> Replacement of transformer oil
> Replacement of necessary seals
> Modernization or replacement of available control panel
> Replacement and capacity increase of cooling system
> Provision of automated voltage regulator panel and its adaptation to available system
> Provision of parallel operation panel and parallel operation of transformers
> Tap changer maintenance.
> Adaptation of online monitoring modules to the transformer

Increasing Efficiency

BEST A.S. ensures performance increase and increase of available values due to all technological innovations, modernization and all equipment controls performed on site.

BEST A.S. ensures performance increase for transformers with all technological advancements and on-site equipment controls.

BEST A.S. has a competent work force experienced in assembly, commissioning and maintenance of power and distribution transformers.

Engineering and Consultancy Services

BEST A.S. is at your service to solve complicated problems with its experience in worldwide transformer expertise. Foundations of a successful future can be laid with optimum selection, analysis and expertise of materials, implementation of action plant, and training.


BEST A.S. provides comprehensive and improving training programs for the personnel of our establishment. These trainings, particularly specialty trainings, are plant trainings and trainings on the job. BEST A.S. intends to increase customer satisfaction and increase quality to a high level with these trainings and implements them with such intentions.

On the other hand, theoretical and applied trainings are given with necessary state of the art devices and supporting training materials in modern training halls, accompanied by professional trainers that have expertise on customer demands.

> General Transformer Technical Training
> Applied Assembly Training
> Commissioning Training
> Field Tests Training
> Transformer Basic Maintenance Training