Bursa Transformer Maintenance, Testing, Oil Analysis and Fault Repair

We provide transformer maintenance, transformer tests, transformer oil analysis, fault maintenance-repair and transformer testing-commissioning services for industrial facilities, factories in organized industrial zones, power generation-distribution facilities and large buildings using power and distribution transformers in Bursa. As a Bursa transformer maintenance company and transformer service provider, our aim is to ensure safe and efficient transformer operation, reduce unplanned outages and detect faults before they occur through a predictive maintenance approach. For related context, see Bursa Transformer Periodic Inspection and Testing.

While transformer operation responsibility service covers regulation-compliant operation, record follow-up and signing responsibility, the Bursa transformer maintenance, testing and repair services described on this page cover periodic maintenance, electrical tests, transformer oil testing and analysis, transformer measurements, fault maintenance and MV transformer maintenance-repair works directly related to the transformer itself. The two services complement each other but their scopes and responsibility areas are different. For related context, see Bursa Generator Periodic Inspection.

Transformer maintenance is required to keep the ageing insulation system, loosening connection points and transformer oil losing its properties under control against heating-cooling cycles, short circuits, impulse voltages, mechanical stresses and environmental effects. If regular maintenance and routine tests are not performed, serious risks such as internal faults, dielectric breakdown of oil, busbar and terminal burns, circuit breaker trips and even fire may occur. Therefore, electrical transformer maintenance is an inseparable part of periodic inspection obligations under Law No. 6331 and the Regulation on Health and Safety Conditions in the Use of Work Equipment. For related context, see Bursa Grounding Measurement and Report.

We begin with a site survey and existing condition assessment. Transformer type (oil-immersed or dry-type), rating, voltage level, brand, age, connected MV switchgear arrangement, protection-measurement relays, cable supplies and previous transformer maintenance and test reports are reviewed. When required, factory routine tests and previous acceptance tests are also reviewed, the scope of electrical tests to be applied in the field is clarified and a maintenance program suitable for outage windows is prepared. For related context, see Bursa High Voltage (HV) and Medium Voltage (MV) Services.

Our routine transformer test package includes the main electrical tests answering the question of which transformer tests are performed: TTR (turns ratio) test, winding DC resistance measurement, insulation (megger) test, and where required, power factor / tan-delta, short-circuit impedance, load and no-load loss measurements, magnetic balance and vector group checks. With these tests, winding faults, contact problems, connection errors, insulation weaknesses, unbalanced loading and installation-related errors are detected at an early stage.

There are some differences between routine tests applied to dry-type transformers and oil-immersed transformers. In dry-type transformers, partial discharge, surface contamination, temperature rise and air-channel cleanliness come to the fore; in oil-immersed transformers, additional parameters such as oil dielectric strength, moisture in oil and cellulose insulation condition are checked. Within this framework, power transformer tests and distribution transformer tests are planned separately; special steps are defined when dry-type transformer repair-maintenance or hermetic distribution transformer maintenance is required.

Transformer electrical tests should be considered together with the protection system and cables on the MV side. Therefore, when necessary, MV switchgear tests, circuit breaker and disconnector checks, protection relay secondary / primary tests, cable insulation tests, grounding resistance and touch voltage measurements are planned as a single package for the transformer substation. HV transformer tests and commissioning steps before energization are carried out in an integrated manner with our HV/MV testing, maintenance and repair service.

In oil-immersed transformers, transformer oil testing and oil analysis are among the most critical predictive maintenance tools that provide information about internal health. Oil samples are taken according to IEC/ASTM standards and parameters such as dissolved gas analysis (DGA), breakdown voltage (BDV), moisture, acidity (TAN), color, sludge tendency and, when required, furanic compounds are examined. Thus, arcing, partial discharge, overheating, cellulose aging and insulation damage that is difficult to reverse can be detected at an early stage even when the transformer appears normal from outside.

According to transformer oil test and oil analysis results, actions such as oil treatment, oil regeneration, complete oil replacement, elimination of oil leaks or reassessment of the loading profile are recommended. With mobile oil treatment devices, oil processing can be carried out on site; in this way, the electrical and chemical properties of transformer oil can be improved without removing the transformer from the field. When oil analysis trends are followed over years, the maintenance interval can be optimized with numerical data.

During mechanical and visual checks, the transformer tank, expansion tank, radiators, connection bolts, terminals, MV/LV busbars, cable terminations and joints, bushings, tap changer and cooling fans/pumps are examined in detail. Points with abnormal temperature rise observed during infrared scans with a thermal camera may indicate loose connection, overload, unbalanced phase current or internal fault. The practical answer to how a faulty transformer is detected is the combined evaluation of these measurements, tests and observations; when required, tightening, cleaning, oxide removal, improvement of insulation distances and part replacement are performed on site.

Transformer fault maintenance-repair works cover many items such as elimination of oil leaks, gasket and bushing replacements, tap changer maintenance and setting, renewal of cooling fans/pumps, revision of circuit breakers and disconnectors in MV switchgear, and cleaning of transformer cabinets and panels. In cases with heavy winding damage or comprehensive oil processing needs, transformer repair, winding renewal, oil treatment / oil regeneration and workshop tests are organized together with partner workshops; field and laboratory results are evaluated together.

In new transformer substation investments or capacity increase projects, we work together with our LV/MV/HV project design and consultancy team for transformer selection, MV switchgear and cable projects, protection relay coordination, factory tests, field acceptance tests, testing and commissioning steps and energization scenarios. Electrical tests performed during first commissioning create reference values for future periodic maintenance, measurements and tests and allow the aging curve of the equipment to be monitored numerically.

When planning transformer maintenance, production outages, maintenance windows, shift order, number of transformers and criticality of the facility are evaluated together. Some checks are performed while energized, such as online measurements and thermal scans, while comprehensive electrical tests are performed after the transformer is safely de-energized. Thus, occupational safety rules are followed and transformer maintenance intervals become compatible with production plans of facilities in Bursa. Contracted maintenance, periodic programs and emergency response services can be configured together when needed.

All measurement and test results are delivered as an official transformer maintenance and test report together with the devices used, reference / limit values, photographs and thermal images when required. The report clearly states tests performed, detected nonconformities, recommended corrective-preventive actions and parameters to be followed. These reports and the transformer maintenance / test forms used can serve as technical references in your electrical installation periodic inspection and other examination files.

The transformer maintenance interval is determined according to transformer rating, loading profile, environmental conditions, facility criticality, previous faults and test results. The general approach is to perform comprehensive transformer maintenance and routine tests at least once a year for power and distribution transformers, and to monitor the condition with intermediate oil analyses and control measurements when required. If desired, this continuity can be managed by integrating it with transformer operation responsibility and HV operation responsibility contracts.

The service fee is determined project-specifically according to the number and rating of transformers, whether they are oil-immersed or dry-type, requested test scope such as routine tests, acceptance tests, oil tests, MV switchgear and cable tests, time to be spent on site, special test equipment to be used and facility location. In Bursa and nearby regions, especially Nilufer OSB, DOSAB, Hasanaga, Kayapa, Kestel, Gursu and Inegol OSB, we perform site surveys and provide clear, understandable and comparable proposal options for transformer maintenance-repair, transformer repair in Bursa and testing-commissioning.