** NEW ** TWR 250B 3PHASE TRANSFORMER WINDING RESISTANCE AND TURNS RATIO

he battery operated TWR250B is the latest DV Power solution for three-phase transformer 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 has the option of the automated test mode, where the instrument operates the tap changer without operator input (minimizing the risk of human error) and records winding resistance and turns ratio results based on pre-selected criteria.

Together with the turns ratio, the instrument also measures excitation current and phase shift. This enables detecting transformer core, or winding turns failures which cannot be spotted by measuring turns ratio only. It has a built-in true three-phase power source. For that reason, they can test transformers with special configurations, such as phase-shifting, rectifiers, arc-furnace, traction transformers, etc.

The instrument can output test current up to 25 A DC for winding resistance tests and voltage up to 250 V AC for turns ratio test, but it can also output a very low-test voltage of 1 V AC which is necessary for turns ratio verification of the majority of current transformers .

TRT250B is equipped with a large 10.1” graphical touch-screen display. The most important are test templates and automatic test mode. Users can simply create test templates, store them in the instrument’s memory, and load them when 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 (11 kg only) and powered by an internal Li-Ion battery.