The Yokogawa WT3000E Transformer Version is a precision power analyser dedicated to testing the power transformers used in the power utilities transmission and distribution sectors. This instrument provides basic power accuracy of ±0.01% reading, DC and 0.1 Hz-1 MHz measurement bandwidths, and up to four input elements.
With an accuracy of 0.5% at power factors as low as 0.01 at 100 V and 1 A, the WT3000E Transformer Version is suited to the precision testing of transformer losses, allowing transformer manufacturers to avoid potential fines imposed by power authorities.
“When every kilowatt lost beyond specified limits can cost thousands of dollars in fines, it is vital to have confidence in the measurement of power losses, particularly under no-load conditions and at power factors as low as 0.01”, says Terry Marrinan, Vice-President, T&M Business Unit, Yokogawa T&M Europe and Asia Pacific: “To address this challenge, the WT3000E Transformer Version is calibrated at power factors of 1, 0.5, 0.05, 0.01 and 0.001 to enable engineers in transformer testing to accurately capture and measure any drift outside the limits described in the IEC60076-8 Standard.” As a result, the WT3000E Transformer Version further exceeds the requirements for accuracy in the standard at a power factor of 0.01 and is now also specified down to a power factor of 0.001.
The WT3000E Transformer Version maintains high levels of accuracy over a wide range of power factors. The ±0.01% total power accuracy figure applies at a power factor of 1 and a frequency of 44-66 Hz. The corresponding value for power factors in the range 0.02 to 0.01 is 0.5%, and for power factors in the range 0.01 to 0.001 it is 7%.
Every instrument is supplied with a calibration certificate from Yokogawa’s ISO 17025 accredited calibration laboratory in the Netherlands. As ISO 17025 certified non-governmental organisation that offers calibration up to 100 kHz, Yokogawa is equipped to guarantee the specifications of its power meters and improve them with calibration.
Like other models in the Yokogawa WT3000E Series, the WT3000E Transformer Version features an intuitive 8.4-inch high-resolution TFT display which can be used to compare up to four waveforms in split-screen mode with clear safety & overload indicators.
The WT3000E Transformer Version features measurement ranges that are optimised to match the potential and current parameter values used in the transformer industry. It also enables users to measure harmonics and distortions while simultaneously measuring power. It can analyse and display a waveform’s individual frequency components, as well as checking signal components other than the integer multiples of the fundamental wave.
User-defined triggers can be set to capture readings that satisfy or fall outside user-defined conditions. Users can also define and use up to 20 custom computations.
Delta computation, provided as a standard function, allows calculation of individual phase voltages from line voltages measured in a 3-phase/3-wire system. Another standard feature is cycle-by-cycle trend analysis, which allows users to list voltage, current, active power and other parameters for each cycle. Direction sensitive energy measurements are also enabled, with the facility for the integration of instantaneous values for positive and negative readings.
The instrument is supplied with free application software which is used to read numeric, waveform, and harmonic data through a communications interface such as GP-IB, USB or Ethernet.