The Megger TTR100 applies voltage, with voltage ratio being directly proportional to turns ratio, to the high-voltage winding of a transformer and accurately measures the resulting voltage from the low voltage winding. In addition to turns ratio, the unit measures excitation current, phase angle deviation between the high and low voltage windings, percent ratio error, dc winding resistance and polarity. The TTR100 is particularly suited for testing in substations and transformer-manufacturing environments where testing single and three-phase transformers can be performed.

The unique design of the TTR100 allows the user to operate the test set while holding it in one hand and features a high contrast LCD screen which can be seen in bright or ambient light. The Megger TTR100 comes equipped with sufficient onboard memory to store up to 200 test results (including test report header information) in the field for later retrieval, as well as 100 user-defined transformer settings. Test results can be printed on an optional serial printer whenever a hard copy is desired, or the data can be downloaded to a PC.

• Powered by rechargeable battery, provides up to fifteen hours of field operation
• Measures the wide turns ratio range (20,000:1) with the high accuracy (±0.1%, 0.8 to 2000) at a low excitation voltage
• Enables the operator to enter the ratio of the transformer and all of its taps to show when a tap is outside acceptable limits
• Measures the phase deviation (in minutes, degrees or centiradians) of the transformer primary versus secondary
• Can be used for inspection purposes to determine the no-load accuracy of most CTs and PT
• Quick Test mode provides a fast determination of the turns ratio, excitation current, phase angle deviation, and winding resistance in single- and three-phase transformers and CTs
• Automatic self-calibration for each test
• Three user selectable standards: ANSI, IEC, and Australian.