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With basic power accuracy of ±0.01% reading, DC and 0.1 Hz-1 MHz measurement bandwidths, and up to four input elements, the WT3000E provides high-accuracy measurement of I/O efficiency.

• Basic power accuracy: 0.01% of reading
• Both 2 A and 3low0 A input elements can be installed in a single unit
• Good readability: 8.4-inch LCD and the range indicator LEDs
• Simultaneous measurement with 2 units (Up to 8 power input elements)
• Store function: 50 ms data storing interval
• Multiple computer interface: GP-IB, Ethernet, RS-232 and USB
• Advanced computation function: Waveform computation, FFT analysis, waveform sampling data saving.
• The latest IEC61000-3-2 and IEC61000-3-12: Harmonic measurement 
• The latest IEC61000-3-3 and IEC61000-3-11: Voltage fluctuation / flicker measurement

Select the model most suited to your measurement needs

• High accuracy and wide frequency range:
  Basic power accuracy:
      ±(0.01% of reading + 0.03% of range)
  Frequency range:
      DC, 0.1 Hz to 1 MHz

• Low Power Factor Error:
  Power factor error when cos ø=0:
    0.03% of S where
    S is reading value of apparent power
    ø is phase angle between voltage and current

• Current Range:
  Direct Input:
      0.5/1/2/5/10/20/30 [A] or 5/10/20/50/100/200/500 [mA], 1/2 [A] *
      2A and 30A input elements can be installed together in a unit.

• External Input:
      50m/100m/200m/500m/1/2/5/10 [V]

• Voltage Range and current range are for crest factor 3
  
  • 1000 [Vrms] Continuous maximum common mode voltage (50/60 Hz)
  • Data Update rate: 50 ms to 20 sec
  • Effective input range: 1% to 130%
  • Simultaneous measurement with 2 Units

Rear Panel

Characteristics 

Example of basic characteristics showing the WT3000E’s high precision and excellent stability

Delta Calculation Function

Checking phase voltage when you measure line to line voltage

This function allows you to calculate individual phase voltages from the line voltage measured in a threephase, three-wire (3V3A) system. R-S line voltage can be calculated in systems measured from a three-phase, three-wire method (using two elements). This is useful when you want to determine the phase voltage in motors and other items under test with no neutral lines. Line to line voltage and phase current (measurements equivalent to 3V3A) can be estimated in systems not measured from a three-phase, three-wire configuration (using two elements).

With fluctuating data occurring when connecting to interconnected systems, or with motor evaluation*, in certain circumstances you may need to capture rapidly changing phenomena (such as during load fluctuations in a motor). These tasks can be handled effectively with the cycle-by-cycle measurement function. The function takes measurements of parameters such as voltage, current, and active power for each cycle, then lists the data on screen in a time series. Up to 3000 data (measurements of signals from 0.1 Hz to 1000 Hz) can be saved in CSV format. * Requires the motor evaluation option (/MTR)

Example of calculation with the cycle-by-cycle function

Range settings using direct key input

Simpler range settings

The range indicator on the WT3000E is a seven-segment green LED, so the set range can be monitored at all times. The range can easily be switched using the up and down arrows.

 Intuitive control using cursor keys  

Easier cursor navigation and numerical settings Cursor keys can be used to move the screen cursor in four different directions, so it is easy and intuitive to set scaling factor and other settings.

Using item pages to set display preferences 

 Item pages make it easy to set the data you want to view for each experiment 

The WT3000E has nine item pages for displaying measurement values. Once you set the measurement parameters you want displayed on a particular item page, you can easily switch between entire groups of displayed parameters. For example, the following settings make it easy to switch and compare data:

Page 1: Voltage, current, active power, and current frequency for input element 1
Page 2: Voltage, current, active power, and current frequency for input element 2
Page 3: Voltages for input elements 1, 2, 3, and 4
Page 4: Currents for input elements 1, 2, 3, and 4
Page 5: Power for input elements 1, 2, 3, and 4

A Variety of display formats 

 Formats for viewing waveforms as well as numerical values 

The WT3000E lets you display input signal waveforms in addition to numerical value data. This means you don't need to connect a special waveform analyzer just to check signal waveforms. 1 In addition, the optional advanced calculation function lets you display vectors and bar graphs for enhanced visual presentation. The information display shows voltage range, current range, filter, and scaling value all together, making it easy to check your settings. 2 1 Waveforms up to approximately 10 kHz can be displayed accurately. 2 More than 2 sets of same type input elements are required.

50ms data updating intervals 

High-speed measurement to capture rapid data fluctuations 

Fast updating allows you to precisely capture rapidly changing transient states in the measurement subject.

* The WT3000E switches between two different calculation systems depending on the data updating interval. See page other for details.

Compensation functions

For increased measurement precision 

The WT3000E has compensation functions for high-precision measurements. These functions can compensate for instrument-related losses resulting from the power meter’s internal impedance as well as losses related to wiring during measurement with two power meters. The following compensation functions are provided to compensate for instrument-related losses:

• Efficiency compensation: This function compensates for instrument-related losses occurring during efficiency calculation.

• Wiring compensation: This function compensates for instrument-related losses caused by wiring.

When measurements are performed using two power meters with three-phase three-wire wiring, errors may occur if current flows to the middle wire (or if there is a leakage current). The WT3000E has a function to compensate for such errors. Even when measurements are performed with two power meters (requires measurement with three-phase three-wire (3V3A) wiring), the current flowing to the middle wire is calculated, and a corresponding correction value can be added to the power measurement. This improves the accuracy of power measurements.

A way to add user-defined measurement parameters 

 As many as twenty user-defined formulas can be set in the WT3000E. These equations can be used to calculate various parameters, such as mean active power (see "A variety of integration functions" below). 

An easier way to input efficiency calculation formulas 

 This function can be used to set up to four efficiency calculation formulas.

A Variety of integration functions 

Apparent power integration and reactive power integration 

• Active power, current, apparent power, reactive power
  In addition to the active power integration function (WP) and current integration function (q) included in earlier models, the WT3000E also has a new apparent power integration function (WS) and reactive power integration function (WQ).
• A wide effective input range for high-precision integration
  The WT3000E has a wide effective input range, from 1% to 130% of the measurement range. This enables higher-precision integration measurements on measurement subjects with current values that fluctuate widely from large currents down to faint currents in the standby state.
• Mean active power (using user-defined settings)
  Mean active power can be calculated over an integration interval. This feature is useful for evaluating the power consumed by intermittent-control instruments in which the power value fluctuates.

Supports Crest Factor 6

The crest factor is the ratio of the waveform peak value and the RMS value.

  When checking the measurable crest factor of our power measuring instruments, please refer to the following equation.

* However, the peak value of the measured signal must be less than or equal to the continuous maximum allowed input

* The crest factor on a power meter is specified by how many times peak input value is allowed relative to rated input value. Even if some measured signals exist whose crest factors are larger than the specifications of the instrument (the crest factor standard at the rated input), you can measure signals having crest factors larger than the specifications by setting a measurement range that is large relative to the measured signal. For example, even if you set CF = 3, CF5 or higher measurements are possible as long as the measured value (RMS) is 60% or less than the measuring range. Also, for a setting of CF = 3, measurements of CF = 300 are possible with the minimum effective input (1% of measuring range).

Store Function (Comes Standard with WT3000E)

Voltage, current, power, and other measured data can be stored to the unit's approximately thirty megabytes of internal memory. These data can be saved in binary or ASCII format on a PC card or USB memory*.

* The USB port (for peripherals) comes with the /C5 option.

 

Each measured item can be stored every data update interval. You can specify to store only the desired measured items, thus saving memory.

 

Files saved in ASCII format can be opened in general-purpose applications such as Excel allowing display of data in graphs. * Please note that data saved in binary format can only be manipulated using dedicated software to be made available by Yokogawa.