Multi-year transformer O&M programmes
Multi-year scheduled maintenance across a site or network, with the records and trending an asset manager can report from.

Who a multi-year O&M programme is for
A multi-year transformer operation and maintenance (O&M) programme puts a site or a network under one maintenance plan: scheduled testing and service for every unit, a record and a trend for each, and planning that turns those trends into the next period's work. It is a transformer maintenance contract organised around the fleet's evidence: the work is planned from each unit's results, and the results are kept in a form you can report from.
IPP asset managers
Availability obligations to meet, and lenders who expect maintenance they can audit. The programme assembles the evidence for each reporting period as the work is done.
Industrial operators
Plants and industrial groups that want O&M support for their transformers, either embedded with the site or periodic.
Utilities and multi-site groups on framework agreements
Networks and multi-site operators that buy maintenance under a framework agreement over several years, with the records following each unit across every site.
What a multi-year O&M programme includes
Scheduled maintenance across a site or network
Oil sampling, electrical testing and service on a planned cycle, over several years. Oil results are read against IEC 60422, and dissolved gas results are interpreted to IEC 60599.
Embedded or periodic O&M support
For IPPs and industrial operators, O&M support that is either embedded with the site team or delivered periodically.
Records, trending and planning
Fleet asset-management support: a record for every unit, its results trended over time, and planning that turns the trends into the next period's work and budget.
Spares strategy and critical-spare holding
The parts whose absence would keep a unit out of service longest, identified for the makes and types in the fleet and held against it.
Spare parts, new and obsolete
Parts sourced regardless of the make or the year of manufacture, where they can still be obtained.
How the programme runs, period by period
Phases, in order. The first runs once; the rest repeat for each period of the contract.
Baseline
Usually a condition assessment: every unit sampled and tested, so that the programme starts from evidence.
Scheduled visits and sampling
Testing and service to the plan, in the outage windows the site allows.
Records and trends
Each result added to the unit's record and read against its trend.
Planned interventions
Treatment, repair or parts replacement, scheduled from the evidence before a fault forces it.
Planning for the next period
Which units need work next, what that work involves, and what the budget should allow for it.
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.
Records, trends and plans you receive
Records per unit, auditable for lenders
What was tested, when, to which method and with what result, kept for every unit through the contract.
Oil results trended against IEC 60422
Each unit's oil results as a series, so that the direction of every result is visible, not only its latest value.
Planning input
Which units to treat next, and why, for the next period's work and budget.
A spares strategy
The critical spares for the fleet identified, with the reason each one is on the list.
Maintenance testing and the standards behind it
The testing in the programme follows published methods, recorded with every result, so that a trend compares like with like.
| Standard | What it governs here |
|---|---|
| IEC 60475 | Sampling oil for the routine tests at each visit |
| IEC 60567 | Sampling oil for dissolved gas analysis |
| IEC 60422 | Reading oil condition, and trending it through the contract |
| IEC 60599 | Interpreting dissolved gas results as they trend |
| IEEE C57.152 | Guide to the electrical field tests in the plan |
The detail on the capabilities page
Transformer O&M programmes: common questions
What does a multi-year maintenance contract include?
Scheduled maintenance across a site or network over several years; oil sampling and electrical testing on a planned cycle; records and trends kept for every unit; and planning support that turns those trends into the next period's work and budget. It can add a spares strategy, with critical spares identified and held, and embedded or periodic O&M support.
How does the programme help with reporting to lenders?
Lenders and their technical advisers look for maintenance they can audit: what was tested, when, to which method, and with what result against which limit. The programme keeps that record for every unit, with oil results trended against IEC 60422, so the evidence for a reporting period is already assembled rather than collected by hand at the deadline.
How is each unit's maintenance plan set?
From its baseline: the unit's condition, the duty it carries and the direction its results are moving. A unit whose results hold steady keeps its place in the plan; one whose results start to move is brought forward. Harsh duty — heat, heavy loading, frequent cycling — earns a unit closer attention. The plan is revised whenever the evidence changes, rather than fixed for the life of the contract.
What is critical-spare holding?
It means identifying the parts whose absence would keep a unit out of service longest — for the specific makes and types in the fleet, typically bushings, tap-changer components, gaskets and seals — and holding them against the fleet. A failure then waits for fitting, not for procurement. Which parts qualify is decided from the fleet's makes, types and lead times.
Can a contract cover a fleet of mixed makes?
Yes. The work is brand-independent, and a fleet of mixed makes and ages is the usual case. Spare parts, including obsolete ones, are sourced regardless of the make or the year of manufacture where they can still be obtained, and the records follow each unit rather than each supplier.
How does a contract differ from calling someone out when something fails?
A call-out answers one event on one unit. A contract works to a plan for the whole fleet over several years: every unit has a record and a trend, and interventions are scheduled from the evidence before they turn into call-outs. When something does fail, the records already hold the baseline the investigation needs.
Scope this programme for your site
Tell us the assets, the site and the situation. The enquiry form opens with this programme already selected.
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