• TTR20-1
  • Usually ships in 3-4 weeks



  • 10,000:1 turns ratio
  • Turns ratio accuracy:
    • ±0.20% (0.8 to 4,000)
    • ±0.25% (4,001 to 10,000)
  • Less than 5 second measuring time
  • LCD module, adjustable back lighting
  • Operating temp: -5 to 130°F (-20 to 55°C)
  • Operating RH range: 0 to 90% non-condensing
  • Meets IEC-1010-1, CE & ASTM D999.75 requirements

What's in the Box

  • Combined test leads
  • Instruction manual


The Megger TTR20 Transformer Turns Ratio Tester is an automatic hand-held battery operated transformer turns ratio test set. It is used to measure the turns ratio, excitation current and polarity of windings in single- and three-phase distribution and power transformers (tested phase by phase), potential & current transformers, and tapped transformers.

The unique design of the TTR20 allows the user to operate the test set while holding it in one hand. It effectively eliminates the user from having to kneel or bend down to operate the instrument and speeds up testing time. Realizing the extreme environments in which the TTR20 must operate, special attention has been paid to making it extra rugged, with a high impact, shock resistant case, yet incredibly lightweight at a mere 870 g (1.9 lbs).

Its design makes this instrument well suited for use in a variety of harsh environments. The TTR20 is particularly suited for testing in substations, transformer-manufacturing environments, and meter shops. It features a high-contrast, backlit LCD screen which can be seen in bright or ambient light.

This unit measures a high turns ratio of 10,000:1 accurately with the lowest excitation voltage. It is designed for simple, one button operation with the measured results displayed directly on the easy to read LCD or printed to the optional printer. The TTR20 needs no additional software and comes ready to use complete out of the box.