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Bushings being installed with crane support on a transformer in a substation yard

Service

Substation maintenance

Maintenance and integration of MV and HV substations up to 230 kV: breakers, protection, instrument transformers and documented commissioning.

Bushings being installed with crane support on a transformer in a substation yard
What the photo showsBushings being installed with crane support on a transformer in a substation yard.

Operational continuity for your substation. We maintain the primary and secondary equipment of MV/HV substations — from the power transformer to the protection relays — under a checklist and a documented protocol.

A substation is a system of systems: the power transformer, breakers, instrument transformers, boards, protection and the grounding and control infrastructure. Maintaining it well means going through all of them in order, not just the most visible one.

Our scope covers the power transformer (oil, bushings, electrical tests), the breakers (mechanism, contact resistance, timing, extinguishing medium), the boards and cells (cleaning, re-torque, insulators, interlocks), and the protection and control (relay testing, instrument transformers, batteries, coordination).

Everything is executed under safety procedures (lockout/tagout, verification of de-energization, temporary grounding), and closes with a documented protocol by component.

What we maintain

Primary equipment

Power transformer, breakers, disconnectors, instrument transformers and busbars.

When it applies: Scheduled substation maintenance.

Protection & control

Relay testing, instrument transformers, control batteries and coordination.

When it applies: Verification of protection functions.

How we execute the service

Safety

Lockout/tagout, verification of de-energization and temporary grounding.

Inspection & testing

Component-by-component checklist with precision instrumentation.

Intervention

Cleaning, re-torque and correction of findings.

Protocol

Documented report by component with recommendations.

Frequently asked questions — substation maintenance

How often should an MV substation be maintained?

The schedule must be documented against the manufacturer's instructions, asset condition and trends, load, environment, history and failure consequences. Engineering must justify the program and reassess it when anomalies appear; this page does not prescribe a universal interval.

What is checked on the breakers?

Operating mechanism, contact resistance, opening/closing times, condition of the extinguishing medium (vacuum or SF6) and lubrication.

Why include thermography?

It detects loose connections and hot spots with the equipment energized, before the outage, prioritizing where to intervene.

Do you test the protection?

Yes: relays are verified and, where applicable, tested by secondary injection; instrument transformers, control batteries and protection coordination are reviewed.

Substation maintenance in images

Technician in orange coveralls working a hot stick above a power transformer in a substation yard
Technician in orange coveralls working a hot stick above a power transformer in a substation yard
Substation yard with a power transformer and its steel structure, seen against the light
Substation yard with a power transformer and its steel structure, seen against the light
Worker manoeuvring on the equipment beside an insulator stack in a substation yard
Worker manoeuvring on the equipment beside an insulator stack in a substation yard
Two workers between the bushings of a transformer with crane support
Two workers between the bushings of a transformer with crane support
Three workers on the bushings and surge arresters of a transformer
Three workers on the bushings and surge arresters of a transformer
Technician pressure-washing substation equipment amid clouds of water vapour
Technician pressure-washing substation equipment amid clouds of water vapour

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