Transformer Testing Services Australia
Comprehensive Power Transformer Testing and Diagnostics Across Australia
Power transformers are the single highest-value assets in any substation. A failure can cost millions in replacement, lost production, and consequential damage. Megavar provides comprehensive transformer testing for commissioning, routine maintenance, condition assessment, and post-fault investigation of power transformers from 11 kV distribution class through to 500 kV EHV transmission class.
Our testing methodology detects incipient faults at the earliest possible stage, enabling asset owners to make informed decisions about maintenance, refurbishment, or replacement.
Electrical Tests
- Turns ratio (TTR) — Voltage ratio on all tap positions. Tested to IEC 60076-1 with accuracy better than 0.1%.
- DC winding resistance — All phases and tap positions to detect poor connections, broken strands, and high-resistance joints. Includes OLTC contact resistance trending.
- Insulation resistance (IR) — Winding-to-winding and winding-to-earth at standard test voltages. Includes polarisation index (PI) and dielectric absorption ratio (DAR).
- Insulation power factor / tan delta — Dielectric dissipation factor to assess insulation condition, moisture, and contamination. Standard and elevated voltages with tip-up analysis.
- Sweep frequency response analysis (SFRA) — Frequency-domain measurement to detect winding deformation, core displacement, and transport damage. Compared against factory baselines.
- Capacitance measurements — Winding and bushing capacitance for condition trending and bushing serviceability.
- Short-circuit impedance — Impedance measurement to detect winding displacement. Compared against factory certificates.
- Excitation current — No-load excitation to detect core faults, shorted turns, and core insulation degradation.
Oil Testing
- Dissolved gas analysis (DGA) — Insulating oil sampling for dissolved gas concentrations. Interpreted using Duval Triangle, Rogers Ratio, and Key Gas methods.
- Standard oil tests — BDV, moisture, acidity, interfacial tension, colour, dissipation factor. Tested to AS 1767 and IEC 60422.
- Furan analysis — Furanic compound measurement to estimate cellulose insulation degradation and remaining life.
Mechanical and Accessory Testing
- OLTC testing — Dynamic resistance measurement (DRM), transition timing, motor current analysis, and compartment oil sampling.
- Bushing testing — Tan delta, capacitance, and power factor. Comparison against factory values and trend data.
- Cooling system — Fan/pump operation, oil flow, temperature gauges, and cooling control logic verification.
When Transformer Testing Is Required
- New installation commissioning (site acceptance testing)
- Routine maintenance programmes (condition-based or time-based)
- Post-fault investigation following protection operation or through-fault
- Condition assessment prior to asset acquisition or insurance renewal
- Pre- and post-transport testing for relocated transformers
- End-of-life assessment and remaining-life estimation
Standards
All testing per AS 60076, IEC 60076, IEEE C57.12.00, IEEE C57.12.90, CIGRE TB 761, and relevant NSP maintenance standards. Equipment calibrated traceable to the National Measurement Institute (NMI).
Check the FRANEO 800 sweep frequency response analyser.
Frequently Asked Questions
Transformer Testing Services Australia
What is SFRA and why is it important?
Sweep Frequency Response Analysis measures winding impedance across a wide frequency range. The unique frequency trace is compared against factory baselines. Any deviation indicates mechanical changes — winding deformation, core displacement, or loose clamping. Critical after transport, through-faults, or seismic events.
How often should power transformers be tested?
What is dissolved gas analysis (DGA)?
What voltage classes does Megavar test?
Does Megavar provide condition assessment reports?
Yes. Detailed reports include all results, factory data comparison, DGA interpretation, trend analysis, and actionable recommendations for maintenance, monitoring, or further investigation.
Ready to commission your substation? Contact Megavar today on 1300 730 499 or visit our contact page to request a quote.
Explore Our other services
Expert BESS commissioning services across Australia. Megavar delivers HV testing, protection validation, SCADA integration, and grid compliance for battery energy storage systems from 5MW to 500MW+.
HV earthing design and testing: earth grid design, EPR calculations, step and touch voltage analysis, soil resistivity surveys, and compliance testing per ENA EG-0 across Australia.
Power system studies: load flow, short circuit, protection coordination, harmonic analysis, arc flash, and earthing studies. Supporting HV design, compliance, and grid connections across Australia.
Trusted by top enterprises for exceptional results
Explore the latest insights
We’re incredibly excited to share a big milestone in Megavar’s story—we’ve officially opened our new Newcastle branch, located at 22 Gavey Street, Mayfield,
