Transformer installation and commissioning projects
New assets from delivery to energisation, with the test evidence a lender or an asset owner reviews before accepting the asset.
Who transformer commissioning projects are for
A transformer commissioning project takes a new unit from delivery to its first day on load: inspection on arrival, assembly, vacuum filling, the pre-energisation tests, and the site acceptance test (SAT) documentation the asset is accepted on. Every step leaves a record. The same programme moves an existing transformer to another site, or takes one out of service.
EPC project managers
Commissioning inside a larger project, measured against the project schedule. The mobilisation plan names the equipment, the route, customs clearance, permits, the team and the dates before anyone travels, and the test schedule is agreed with you before site work starts.
IPPs and their lenders
A new asset is accepted on evidence. Every result in the commissioning schedule is recorded with the method it was carried out to and the value it was checked against, in a form a lender's technical adviser can review.
Solar, wind and storage projects
Transformers for solar, wind and battery storage plants and their collector substations, often on remote sites and working to a fixed grid-connection date.
Owners moving or retiring a unit
An existing transformer to be relocated to another site, or decommissioned, de-oiled and disposed of at the end of its service.
What installation and commissioning includes
The scope of a new installation from arrival to handover, then the work on existing units. Switchgear and protection installed with the transformer can be commissioned in the same project.
Receipt inspection on delivery
The transformer is inspected when it arrives, and its transport-shock record is reviewed, before assembly begins.
Off-loading, positioning and assembly
The unit is off-loaded, set in position and assembled. Heavy lifts and abnormal road moves are planned in: cranes and haulage arranged, and the route survey and permits completed before the transformer moves.
Vacuum filling and oil processing
The tank is filled under vacuum, which keeps air and moisture out of the insulation, and the oil is processed on site. New oil is specified to IEC 60296, and its processing in the equipment follows IEC 60422.
Oil acceptance tests
Breakdown voltage to IEC 60156 and water content to IEC 60814, measured on the oil before filling and again after it.
The pre-energisation test schedule
Winding resistance, voltage ratio and vector group, capacitance and tan delta, core insulation and short-circuit impedance to the routine-test methods of IEC 60076-1, with insulation resistance, polarisation index and a frequency-response trace to IEC 60076-18. Each result is compared with the factory test report.
Switchgear and protection commissioned with it
Where circuit breakers and protection relays are installed with the transformer, breaker tests follow IEC 62271-100 and relay tests IEC 60255-1.
SAT documentation
The record of the site acceptance tests, for each transformer and item of equipment commissioned.
First energisation and handover
The unit is energised for the first time, load-tested and handed over to its owner with the SAT documentation.
Relocation, decommissioning, de-oiling and disposal
An existing unit moved to a new site or retired from service. The oil is removed under a documented chain of custody, and a relocated transformer is tested again before it returns to service.
How a commissioning project runs, from delivery to first load
Phases, in order. The dates come from the mobilisation plan agreed after the site survey, and the test schedule is agreed before site work starts.
Receipt inspection
The condition on arrival recorded before anything is fitted.
Positioning and assembly
The transformer set in place and its fittings mounted, against agreed method statements.
Vacuum filling and oil processing
The oil tested before it goes in, filled under vacuum, processed, and tested again.
Pre-energisation tests
The agreed schedule, with each result read against the factory test report.
SAT documentation
The results assembled into the record the asset is accepted on.
First energisation and load testing
The unit switched in for the first time and brought onto load.
Handover
The transformer handed to its owner with its SAT documentation and its frequency-response fingerprint.
What you provide
The assets and the site
The organisation, the site, the number of transformers with their rating and voltage ranges, the situation and your timeline: what the enquiry form asks for.
Existing records
DGA results, oil analysis and test reports, sent as a reply to our acknowledgement. A result means more when it is read against the same unit's history.
Outage windows
When each unit can be switched off, whether a regulated outage plan or a load-shedding rota sets it. Tests and work that need a de-energised unit are planned into those windows.
Access to the site
Access, ground conditions, crane availability and supply, confirmed at the site survey before a price is fixed.
What the commissioning record gives you
SAT documentation
Every test result with its method and the acceptance value it was checked against, in the form an asset owner or a lender's technical adviser reviews.
A frequency-response fingerprint
The trace recorded at commissioning becomes the unit's reference. After a close-in fault or a move, a new trace is compared with it.
A baseline for maintenance
The commissioning results become the values that later maintenance results on the same unit are compared with.
An energised transformer
The unit in service, with every step from delivery to first load on record.
Pre-energisation tests and the standards they follow
Every test in the commissioning schedule follows a published method, and the method is recorded beside its result.
| Standard | What it governs here |
|---|---|
| IEC 60076-1 | Routine tests on power transformers: the methods behind the pre-energisation schedule |
| IEC 60076-18 | The frequency-response trace recorded as the unit's fingerprint |
| IEEE C57.152 | Guide to diagnostic field testing of the transformer |
| IEC 60296 | The new mineral oil the tank is filled with |
| IEC 60156 | Breakdown voltage of the oil, before and after filling |
| IEC 60814 | Water content of the oil, before and after filling |
| IEC 60422 | Processing the oil once it is in the equipment |
| IEC 62271-100 | Circuit-breaker tests, where switchgear is commissioned with the transformer |
| IEC 60255-1 | Protection relay tests, where protection is commissioned with the transformer |
The detail on the capabilities page
Transformer commissioning: common questions
What is tested before a new transformer is energised?
A pre-energisation schedule typically covers winding resistance, voltage ratio and vector group, insulation resistance and polarisation index, capacitance and tan delta of windings and bushings, core insulation, and a frequency-response trace to IEC 60076-18. The oil is tested before and after filling. The results are compared with the factory test report, and the schedule is agreed with the owner or the EPC before site work starts.
Why record a frequency-response trace at commissioning?
Because it becomes the transformer's fingerprint. If the unit later rides through a close-in fault, or is moved, a new trace compared with the commissioning one shows whether the winding geometry has changed. Without that baseline the comparison cannot be made, and a later trace is much harder to interpret. The measurement follows IEC 60076-18.
What does the SAT documentation contain?
The result of every test in the agreed schedule, for each transformer and item of equipment commissioned, with the method it was carried out to and the acceptance value it was checked against. It is the record an asset owner, or a lender's technical adviser, reviews before accepting the installation, and it becomes the baseline that later maintenance results are compared with.
Does the programme cover delivery, lifting and assembly?
Yes. It starts with receipt inspection on arrival, including a review of the transport-shock record, and continues with positioning and assembly, vacuum filling and oil processing. Where heavy lifts or abnormal loads are involved, cranes and haulage are arranged as part of the plan, with route surveys and permits settled before the unit moves.
Can an existing transformer be relocated or decommissioned?
Yes. Relocation, decommissioning, de-oiling and disposal are within the programme. The oil is removed and handled under a documented chain of custody, and a relocated unit goes through the pre-energisation tests again before it returns to service, compared with its own earlier results where they exist.
Which standards apply to commissioning tests?
Routine tests on power transformers are defined in IEC 60076-1, and frequency-response measurement in IEC 60076-18. IEEE C57.152 is the guide to diagnostic field testing of fluid-filled transformers, and new insulating oil is specified by IEC 60296. Where switchgear and protection are commissioned with the transformer, breaker tests follow IEC 62271-100 and relay tests IEC 60255-1.
Scope this programme for your site
Tell us the assets, the site and the situation. The enquiry form opens with this programme already selected.