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The 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:
TWR250B is lightweight (11 kg only) and powered by an internal Li-Ion battery.
TWR250B is a three-phase transformer analyzer designed for transformer winding resistance and turns ratio testing. It combines multiple transformer diagnostic functions in a single battery-powered instrument for field and factory applications.
Yes. True three-phase voltage can be applied to simulate real condition of transformer. Maximum aplicable voltage is 250V
TWR250B performs winding resistance measurement, turns ratio measurement, excitation current measurement, phase angle measurement, transformer demagnetization, vector group detection, and turns ratio deviation calculation.
TWR250B allows testing of six transformer windings with a single cable connection. This significantly reduces setup time and eliminates the need for repeated reconnections during testing.
TWR250B can generate up to 25 A DC for transformer winding resistance measurements, ensuring fast saturation and accurate resistance results.
Yes. TWR250B can generate a very low test voltage of 1 V AC, which is suitable for turns ratio verification of many current transformers.
Yes. The instrument offers automated test mode and can operate the tap changer automatically while recording winding resistance and turns ratio results according to predefined test criteria.
Measuring excitation current and phase shift helps identify transformer core defects, winding turn faults, and other issues that may not be detected by turns ratio measurements alone.
Yes. TWR250B performs automatic vector group detection, simplifying transformer commissioning, maintenance, and verification procedures.
Yes. The instrument performs automatic three-phase transformer demagnetization, helping eliminate residual magnetism before testing and improving measurement accuracy.
TWR250B can test conventional power transformers as well as phase-shifting transformers, rectifier transformers, arc-furnace transformers, traction transformers, and other special transformer configurations.
Yes. TWR250B is battery-powered, weighs only 11 kg, and features a large 10.1-inch touch-screen display, making it ideal for substation and field testing applications.
Yes. Users can create test templates, save them in the instrument memory, and quickly reuse them in the field, ensuring consistent testing procedures and reducing setup time.
A combined analyzer such as the TWR250B allows engineers to perform multiple transformer diagnostic tests with one instrument, reducing equipment requirements, shortening outage times, and improving overall testing efficiency.
