Transformer Testing
Understand transformer condition, verify performance and support confident commissioning decisions.
Explore ServiceMEGGER · TAU3
Megger TAU3 True Three-Phase Transformer Winding Analyser
A true three-phase transformer analyser for electro-mechanical testing of power, distribution and instrument transformers, performing turns ratio, winding resistance, demagnetization, short-circuit impedance and efficiency tests with a one-time lead connection.
Official Megger product photography
Transformer winding analysis
Testing capabilities
- One-time lead connection for all tests, with colour-coded leads and on-screen vectors matching the transformer nameplate
- Turns ratio testing up to 250 V AC with ±0.05 % accuracy
- Three-phase winding resistance up to 32 A DC with ±0.10 % accuracy and dual winding excitation
- Automatic adaptive demagnetization after each winding resistance test
- Short-circuit impedance and efficiency tests using the same connections, with patent-pending internal shorting
- Built-in OLTC tap changer control; dynamic resistance, motor current and vibration monitoring options
- Results export as Excel/PDF reports and JSON for PowerDB Lite import
Manufacturer-published capabilities. Available tests depend on the selected configuration and accessories. Confirm suitability, availability and pricing with our technical team.
Technical specifications
| Manufacturer / model | Megger / TAU3 (ADV, PRO, EXP) |
| Input power | 100–240 V AC, 47–63 Hz, 1200 W |
| Output | 3-phase, 1–100 V; DC, 40–480 Hz; 0.1 mA – 1 A @ 100 V; 0.1 mA – 32 A @ 24 V |
| Turns ratio | Up to 250 V AC; ±0.05 % accuracy (0.8–1000 range, step down 25–100 V) |
| Winding resistance | 1.0 μΩ to 30 kΩ; ±0.1 % reading ±1 μΩ; up to 100 V DC open circuit |
| Display | 10.1 in touch screen, 1024 × 600, 1000 NITS |
| Data storage | Up to 10,000 sets of three-phase results, USB 2.0 transfer |
| Safety / EMC | IEC 61010-1:2010 + AMD1:2016; IEC 61326:2020; MIL-STD-810G |
| Dimensions / weight | 55.8 × 28.7 × 19 cm / 17 kg |
| Environmental | −20 °C to +50 °C operating, IP67 in transit case |
Downloads
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