Transformer Testing
Understand transformer condition, verify performance and support confident commissioning decisions.
Explore ServiceMEGGER · MTOU3
Megger MTOU3 Three-Phase Winding Resistance Ohmmeter
A true three-phase winding resistance ohmmeter for power, distribution and instrument transformers, with one-time lead connection, automatic adaptive demagnetization and vector confirmation before every test.
Official Megger product photography
Transformer winding resistance testing
Testing capabilities
- True three-phase winding resistance measurement up to 32 A DC with ±0.1 % resistance accuracy
- One-time lead connection for vector confirmation, winding resistance and demagnetization tests
- Confirm vector: polarity recognition and validation before every test
- Independent dual winding magnetization for fast primary and secondary winding measurements
- Automatic adaptive demagnetization after each winding resistance test
- OLTC control with make-before-break continuity testing and one-touch OLTC operation
- Results export to Excel/PDF reports and PowerDB import and control
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 / MTOU3 (ADV, PRO, EXP) |
| Input power | 100–240 V AC, 47–63 Hz, 1200 W |
| DC open circuit voltage | Up to 100 V (50 V on MTOU3 ADV) |
| Maximum DC output current | Up to 32 A at 24 V (16 A on MTOU3 ADV) |
| Resistance measurement range | 1.0 μΩ to 30 kΩ |
| Resistance accuracy | ±0.1 % reading ±1 μΩ; ±0.5 % reading above 30 kΩ |
| Display | 10.1 in hi-bright touch screen, 1024 × 600, 1000 NITS |
| Data storage | Up to 10,000 sets of three-phase results, USB 2.0 transfer |
| Safety | Key lock, safety interlock and emergency stop; IEC 61010-1 |
| 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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