True three-phase transformer turns ratio tester

  • Guaranteed accuracy ±0.05 % from -20 °C to +50 °C
  • Three-phase test voltage - up to 25 0V
  • Three-phase step up ratio (patent pending)
  • Phase shifting and zigzag transformers tested easily and accurately
  • Smallest/lightest three-phase test set on the market
  • Fast three-phase tests - less than 10 seconds

Megger’s TTRU3 transformer turns ratio tester is a revolutionary instrument designed to perform three-phase turns ratio measurements using step-up excitation (patent pending). A single three-phase lead-set connection is all that is required to complete three-phase tests in less than 10 seconds!

The TTRU3 is capable of three-phase excitation and can induce up to 250 V on the primary winding, overcoming the voltage dependence seen on larger transformers. The three-phase source also allows you to test phase shifting and zigzag transformers, and provides you with a guaranteed accuracy of ±0.05 % from -20 °C to +50 °C.

What’s more, the TTRU3 can be connected to a computer, enabling you to download results or control the instrument remotely. There is also an optional 2 inch printer for the instrument, enabling you to have a hard copy of your results if required.

You can also configure test plans and store results directly on the TTRU3 using the built-in 7 inch (18 cm) daylight-viewable touch screen display. To generate reports, results can be downloaded in Excel, and PDF files can be saved to a USB drive. 

Last but not least, it’s also the smallest and lightest three-phase test set on the market!

Step up your transformer testing with TTRU3

Technical Documents
Technical guide
One touch OLTC with the TTRU3
Technical guide
Transformer turns ratio test: some unknown facts
Technical guide
TTRU3 - 1 phase vs 3 phase
Technical guide
TTRU3 - Magnetic Balance
Technical guide
TTRU3 - Step up vs Step down
Technical guide
TTRU3 Calibration verification
Technical guide
TTRU3 Factory ratio testing of power transformer
Technical guide
TTRU3 Phase Shifting Transformers
TTRU3 3.2.1

To upgrade from 2.2.4 to 3.x.x, the TTRU3 must be returned to a factory or ASC.

TTRU3 Embedded Software

** Once downloaded, the zip file must be extracted before copying the .mender file to the root of a thumb drive **
235.9 MB | 20/06/22
TTRU3 PC Software
32.1 MB | 20/06/22
TTRU3 Release Notes
380.1 KB | 20/06/22
TTRU3 2.2.4
TTRU3 Release Notes
186.3 KB | 05/04/22
TTRU3 PC Software
42.0 MB | 05/04/22
TTRU3 Embedded Software
** Once downloaded, the zip file must be extracted before copying the .gz file to the root of a thumb drive **
87.8 MB | 05/04/22