23 Jul 2024


Multi-function power analyser is ‘world’s most accurate’

Yokogawa has announced a power analyser that it claims is the world’s most stable and accurate. The WT3000E analyser – an enhancement of the earlier WT3000 – has a 45–65Hz accuracy of 0.01% of reading, plus 0.03% of range, based on RMS values rather than the waveform peak values used by some manufacturers.

Because power ranges are multiples of the voltage and current ranges, the actual power measurement error due to an uncertainty of 0.03% of range is less than 0.01% of range for a power meter based on peak values.

The analyser can calculate individual phase voltages from the line voltage in a three-phase/three-wire system. This can help to determine phase voltages in applications such as motor testing where there are no neutral lines.

Another standard function, called cycle-by-cycle analysis, allows users to list measurement parameters such as voltage, current and active power in a time series for each cycle. Input frequencies from 0.1–1,000Hz can be measured, and up to 3,000 items of data can be saved. Free software is available to display the data graphically by cycle, thus offering a “unique” method of capturing fluctuating transient power with high precision.

The WT3000E can mix 30A and 2A input current elements, enabling users to use one instrument to test that products comply with harmonics, flicker and standby power standards.

The analyser offers various alphanumeric and graphical display formats, including the ability to display the input signal as a waveform. It also offers high-speed data updating, allowing users to capture fast-changing transient signals with high precision for further analysis.