TWR250B - Turns Ratio and Winding Resistance Analyzer

Turns Ratio and Winding Resistance Analyzer TWR250B

The battery operated TWR250B is the latest DV Power solution for three-phase transformers designed for measuring transformer winding resistance and turns ratio.

TWR250B is capable of testing six transformer windings with a single cable connection, as well as three-phase automatic transformer demagnetization. It also offers an automated test mode, where the instrument operates the tap changer without operator input and records winding resistance and turns ratio results based on pre-selected criteria.

Together with turns ratio measurement, the instrument also measures excitation current and phase shift. This helps detect transformer core or winding turns failures that cannot be identified by turns ratio measurement only.

The instrument has a built-in true three-phase power source, allowing it to test transformers with special configurations such as phase-shifting transformers, rectifiers, arc-furnace transformers, traction transformers, and other transformer types.

TWR250B can output test current up to 25 A DC for winding resistance tests and voltage up to 250 V AC for turns ratio tests. It can also output a very low test voltage of 1 V AC, which is needed for turns ratio verification of most current transformers.

The TWR250B is equipped with a large 10.1” graphical touch-screen display. Test templates and automatic test mode allow users to create templates, store them in the instrument memory, and load them in the field with just a few clicks.

The list of instrument applications includes:

• Winding resistance measurement
• Demagnetization
• Turns ratio measurement
• Turns ratio deviation calculation
• Excitation current measurement
• Phase angle measurement
• Automatic vector group detection

TWR250B is lightweight at only 11 kg and powered by an internal Li-Ion battery.

Specifications