DV Power TWA40D Three-Phase Winding Ohmmeters & Tap Changer Analyzers

The Tap Changer & Winding Analyzer TWA40D is designed for six-winding resistance measurement and simultaneous three-phase on-load tap changer analysis of both the primary and the secondary transformer windings. This is performed with a one single-step cable setup, with test currents of up to 40 A. Each transformer configuration has a special measurement algorithm which is optimized for the fast stabilization of test results. Additional testing mode, Quick YN, is enabled by the DV-Win software. In this mode, it is possible to measure the resistances of three transformer windings in the YN configuration simultaneously. It is also possible to test the resistances of all tap changer positions of all three phases in a single pass through the tap changer positions. TWA Series The TWA series instruments are designed for six-winding resistance measurement of power and distribution transformers. As well as resistance measurement of inductive test objects. In addition, they provide powerful tap changer analysis options by using proprietary, non-intrusive DVtest features. They generate true DC ripple free current with automatically regulated measurement and discharging circuit. The transformer measurements performed with the TWA instruments require only one single-step cable setup. Each transformer configuration has a special measurement algorithm. They are optimized for the fast stabilization of test results. The test current can be automatically passed through the HV and LV winding simultaneously in order to achieve shorter stabilization times. The TWA40D model is a true three-phase instrument capable of simultaneously measuring winding resistances of three phases of YN configuration. As well as three-phase tap changer analysis. All TWA instrument models are capable of both single-phase and three-phase demagnetization. The DV-Win software, provides full control of all TWA functions from a PC and additional test and analysis modes and features, is included with the TWA instruments. DV-Win software The DV-Win software enables control and observation of the test process, as well as saving and analyzing the results on a PC. It pro-vides a test report, arranged in a selectable form as an Excel spreadsheet, PDF, Word, or ASCII format. The software provides an OLTC (tap changer) condition assessment through analysis of the graphs representing dynamic resistance values during the tap changer transitions. Additionally, the DV-Win measures and calculates the OLTC transition time, the ripple and the winding resistance for each tap changing operation. The standard interface is USB. RS232 is optional. Additional testing mode, Quick YN, is enabled by the DV-Win software. In this mode, it is possible to measure the resistances of three transformer windings in the YN configuration simultaneously. It is also possible to test the resistances of all tap changer positions of all three phases in a single pass through the tap changer positions.