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The WT3000 is the ideal measurement solution for applications such as product efficiency testing, engineering, R&D work on inverters, motor drives, lighting systems and electronic ballasts, UPS systems, aircraft power systems, transformer testing and other power conversion devices.

What's New

  • Released firmware Version 5.22

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With basic power accuracy of ±0.02% reading, DC and 0.1 Hz-1 MHz measurement bandwidths, and up to four input elements, the WT3000 provides higher-accuracy measurement of I/O efficiency.

  • Basic accuracy: 0.01% of reading
  • Basic power accuracy: 0.02% of reading
  • 2A current input element
  • Good readability: The large, 8.4-inch LCD and the range indicator LEDs
  • Simultaneous measurement with 2 units (8 power input elements)
  • Store function: 50 ms data storing interval
  • Interface: GP-IB, Ethernet, RS-232 and USB
  • Advanced computation function: Waveform computation, FFT analysis, waveform sampling data saving.
  • IEC61000-3-2 and IEC61000-3-12: Harmonic measurement 
  • IEC61000-3-3 and IEC61000-3-11: Voltage fluctuation / flicker measurement
  • IEC61000-4-15 Ed2.0 (Support Flicker meter standard) Update!

More Precise. More Bandwidth. More Features.

  • The WT3000 is a truly innovative measurement solution, combining top-level measurement accuracy with special functions.*
  • The large, 8.4-inch liquid crystal display and the range indicator LEDs ensure good readability and make the system easy to use.
*As compared to Yokogawas WT2000

Have you had problems or questions such as these?

  • When working with efficiency-improvement evaluation data for a high-efficiency motor, improvements cannot be seen unless measurements are taken with very high precision.
  • Measurement efficiency is poor during power measurements and power supply quality measurements.
  • You measure voltage using mean values out of habit, and are wondering if that is really the best approach.
*For answers to these questions, see applications page.

Better Efficiency in Power Measurements

In developing the WT3000, Yokogawa focused on improving efficiency in two basic areas. One goal was to obtain highly precise and simultaneously measurements of the power conversion efficiency of a piece of equipment. The other objective was to improve equipment evaluation efficiency by making simultaneous power evaluations and tests easier and faster.

New Innovations to Enhance the Reliable Measurement Technology;

The Yokogawa WT2000 was very popular with users and considered highly reliable because of its high precision and excellent stability. The WT3000 is based on a measurement system which combines the measurement technology used in the WT2000 as well as other WT Series models. With the WT3000, we made further improvements to the basic performance specifications for even better functionality and reliability. We are confident users will appreciate these improvements to power and efficiency measurements thanks to the new power control technologies we have introduced.

A Variety of External Interface Choices


The WT3000 is the first model in the WT Series which is standard- equipped with a PC card slot (ATA flash card slot). This interface allows data to be saved quickly, so data processing time is reduced. The WT3000 is also standard-equipped with a GP-IB port. In addition, a serial (RS-232) port, Ethernet port, and USB port are available as options. The variety of interface choices allows customers to use the best interfaces for a wide variety of equipment, media, and network environments.


Yokogawa's highest-precision power analyzer *1

The WT3000 has the highest precision of all the Yokogawa power analyzers in the WT series. The models in the WT series are designed to meet a wide variety of user needs. The WT300 series is a high price-performance series which is very popular in production line applications. The WT1800 allows measurement data to be viewed in a variety of ways, including numerical value display, waveform display, and trend display capabilities.

WTFamily 2

*1 As compared to Yokogawa's products
*2 Reading error

Select the model most suited to your measurement needs

Standard Version

  • High accuracy and wide frequency range
    Basic power accuracy
    ±(0.02% of reading + 0.04% of range)
    frequency range
    DC, 0.1 Hz to 1 MHz

  • Low power factor error
    Power factor error when cosø=0
    0.03% of S
    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]
        *Models with input elements supporting current output type current sensors are planned for release

  • External input

    50m/100m/200m/500m/1/2/5/10 [V]*

  • Voltage range
        15/30/60/100/150/300/600/1000 [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%
    • Simultaneously measurement with 2 Units
    • Standard PC card slot

Motor Version

  • Calculation of motor and total efficiency
    In addition to the functions of the standard version, the new models offer powerful motor/inverter evaluation functions
  • Voltage, current, and power measurement with torque and speed input
    Measures torque meter and speed sensor output (analog or pulse output), and allows calculation of torque, revolution speed, mechanical power, synchronous speed, slip, motor efficiency, and total efficiency in a single unit.
Tm Wt3000 04

Rear Panel

Wt3rear Panel


Standard Features Optional Features
  1. Voltage input terminals
  2. Current external sensor input terminals
  3. Current direct input terminals
  4. GP-IB port
  5. BNC connector for two-system synchronized measurement
  1. Serial (RS-232) port (option/C2) or USB port (option/C12)
  2. Ethernet port (100BASE-TX/10BASE-T) (option/C7)
  3. VGA port (option/V1)
  4. D/A output (option/DA)
  5. Torque and speed input terminals (motor version)


 Example of basic characteristics showing the WT3000’s high precision and excellent stability


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 WT3000) 

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.

Excel Example

WT3000 controls: simple to use, easy to view

The WT3000 was designed with user-friendly functions and controls in response to user requests for a simpler range setting operation and more user-friendly parameter setting display process
  •  Range settings using direct key input
  •  Intuitive control using cursor keys
  • Using item pages to set display preferences
  • A Variety of display formats
  • 50ms data; updating intervals; compensation functions
  • A variety of integration funcitons: User-defined function, Efficiency Calculation Function.

Range settings using direct key input 

 Simpler range settings  

The range indicator on the WT3000 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. Wt3range

 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 WT3000 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 WT3000 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.

1 Waveforms up to approximately 10 kHz can be displayed accurately.

2 760302, 760303 and 760304 model. Requires the optional advanced calculation function (/G6)


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 WT3000 switches between two different calculation systems depending on the data updating interval. See page other for details.

Compensation functions 

For increased measurement precision 

The WT3000 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 WT3000 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 (requires /DT option). This improves the accuracy of power measurements.

User-defined function 

A way to add user-defined measurement parameters 

 As many as twenty user-defined formulas can be set in the WT3000. These equations can be used to calculate various parameters, such as mean active power (see "A variety of integration functions" below). 

Efficiency calculation function 

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 WT3000 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 WT3000 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.



A wide variety of optional functions make it easy to perform sophisticated power evaluations.

When you purchase a WT3000 from Yokogawa, you get to select just the options you need. This approach lets you maximize performance at a lower cost.

Advanced Calculation Function (/G6 option)

The Advanced Calculation Function (/G6 option) provides for wide bandwidth harmonic measurement, IEC compliant harmonic measurement (requires harmonic measurement software), FFT calculation, waveform calculation functions, and saving of waveform sampling data.

Wide Bandwidth Harmonic Measurement Mode
Harmonic measurement for a frequency range of 0.1 Hz – 2.6 kHz

Enables harmonic measurement over wide bandwidths. Supports measure-ment of harmonic signals beyond those of the harmonic measurement func-tion in normal measurement mode. This option allows for harmonic analysis on waveforms with a fundamental frequency range of 0.1 Hz–2.6 kHz (*1). You can measure up to the 50th order harmonic at 1 kHz fundamental.(*2).

*1 0.1–10 Hz using an external sampling clock.
*2 Harmonic measurement of up to the 20th order possible in the 1 kHz to 2.6 kHz range.


Harmonic Measurement Function
Same as harmonic Measurement Function /G5

This function enables simultaneous measurement of normal and harmonic data, which was impossible with previous Yokogawa models. Since with the WT3000 you can simultaneously confirm total voltage and current as well as the distortion factor and fundamental wave without switching modes, this allows for more accurate and efficient measurement of the power supply quality, the fundamental wave of motor drive voltage, and other factors.

IEC Harmonic Measurement Mode
Can perform tests conforming to international standards.

The IEC harmonic measurement mode meets the window width requirement of the latest IEC harmonic standard (10 cycles of 50 Hz and 12 cycles of 60 Hz). Also, this mode allows users to use the 761922 harmonic measurement software to perform tests conforming to IEC 61000-3-2 and IEC61000-3-12.

* These modes cannot be used at the same time.


FFT Calculation Mode
More detailed frequency analysis than with the harmonic measurement mode.

Two FFT calculations can be performed simultaneously on waveform data of measured voltage and current. You can select a resolution for FFT of 1 Hz or 10 Hz. FFT analysis of up to 100 kHz can be performed.

Waveform Calculation Mode
Monitoring of instantaneous power waveforms.

Up to two waveform calculations and other Waveform Calculation functions can be used at once. If you create a formula that multiplies voltage and current waveforms, you can confirm an instantaneous power waveform on screen. Waveform Calculation data can be saved in CSV or WVF format.

Waveform Sampling Data Saving Function
Saving of detailed waveform data for confirmation.

All captured voltage and current waveform data (200 kS/s), calculated wave-forms, and FFT calculated waveforms can be saved. You can choose to save in CSV or WVF format, and to save to PC card or USB memory (/C5 option).

Delta Calculation (/DT) 

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).  Wt3delta

Added Frequency Measurement (/FQ) 

Checking the frequencies of all inputs 

In addition to the standard two channels of frequency measurement, a six-channel frequency measurement option is also available. This option provides frequency measurement of voltage and current on all eight channels (with input elements 1 through 4 installed). This is necessary when you want to measure voltage and current frequency from the instrument’s I/O as well as voltage and current frequencies of multiple items under test at the same time. 

D/A Output (/DA) 

Outputting measurement values as analog signals to other devices 

  • 20 channels
    Measured valuescan be output as ±5V 5V FS DC voltages from the D/A output connector on the rear panel. Measured parameters can be output on up to twenty channels simultaneously. Even with four input elements installed, you can send up to five types of data per element to D/A output.
  • D/A zoom
    Normally the D/A output function outputs DC voltage scaled to a range of -5V to 5V* with respect to the measurement range. For this reason, it may not be possible to observe fluctuations in a nearly constant signal if the D/A output is set to go to ±5V at the measurement range rated value. One case in which this could happen is when a 100V measurement voltage fluctuates in the range of ±3V.
    The WT3000 has a D/A zoom function to solve such problems. This function allows the any input signal range to be scaled to between -5V and 5V* in the D/A output as Upper and Lower ranges. This makes it possible to enlarge input signal fluctuations for observation using a recorder or logger.
* The range is 0V to 5V for some functions, such as frequency measurement

Built-in printer(/B5) 

Output graphics at the touch of a button 
The optional built-in printer is installed on the front side of the WT3000, so it is easy to use even if the WT3000 is mounted on a rack. The printer can be used to print data and waveform memos. Wt3printer
Auto Print Function

The Auto Print function allows you to set a time interval at which measured values are automatically printed on the built-in printer. You can also set a start and stop time in order to record data over a desired time period. You can also specify to print only the desired measured items. 

VGA output (/V1) 

Video output for viewing on a larger screen
The VGA port can be used to connect an external monitor in order to view numerical value data and waveforms on a larger screen. This capability is useful if you want to simultaneously check large amounts of data on a separate screen, or view data in a separate location.

Serial (RS-232) (/C2) 

USB Port for Peripherals (/C5 Option) 

A USB port for peripherals with type A connectors can be included with the WT. The various kinds of data stored in the main unit such as voltage, current, and power, can be saved in binary or ASCII format on a peripheral such as a USB memory. You can also connect a keyboard for easy input of user-defined math expressions. Wt3usb

USB Port for Connection to PC (/C12 Option) 

The USB port (type B connector) on the rear panel of the WT3000 allows data communications with a PC¹. Also, instruments with this option installed can be used in conjunction with the communication functions of WTViewer (model 760122, sold separately) for data acquisition via USB².

  1. USB driver required for USB communications. A USB driver is available for download from our Web site.
  2. USB cable for connection to PC not included.

* USB stands for universal serial bus. USB is a standard designed to provide connectivity across a wide range of PC peripherals and other devices through the use of a common communication mechanism. 

Ethernet Communication Function (/C7 Option) 

The option conforms to 100BASE-TX and 10BASE-T and provides for data exchange via communications. The option supports file transfers via FTP server, as well as FTP client (network drives), LPR client (network printers), and e-mail (SMTP client) functions.

* The WT3000 does not have a built-in hard disk. The FTP server function is available when a PC card or USB memory is inserted or connected to the PC.


Cycle-by-cycle function (/CC) 

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 version (-MV) 
Example of calculation with the cycle-by-cycle function



Flicker measurement (/FL) 

This function enables measurement of voltage fluctuations/flicker in compliance with EN61000-3-3 and IEC61000-3-11. It can measure relative working voltage change, maximum relative voltage change (dmax), relative voltage change time (dt), short-term flicker value (Pst), and long-term flicker value (Plt). The initial limit values for the individual parameters are set in accordance with the IEC standard.


IEC61000-3-2 Ed2.2:2004, IEC61000-3-12, JIS C 31000-3-2:2005
(Advanced Calculation Function /G6 and software for testing standards compliance)
IEC61000-3-3 Ed1.1 :2002, IEC61000-3-11
(Voltage fluctuation/flicker measurement, with the /FL option)


Support for IEC and JIS Standards Testing

Model Description
760301 WT3000 1 input element model
760302 WT3000 2 input element model
760303 WT3000 3 input element model
760304 WT3000 4 input element model
Name Description File Type  
Bulletin 7603-00E WT3000 Precision Power Analyzer pdf icon
1.38 MB
Bulletin 7000-30E Measurement Solutions for Vehicle Development pdf icon
1.22 MB
Name Description  
How Green is your Software? Want to know how green is your Software? Intel® Energy Checker and Yokogawa can help you! The Intel® Energy Checker SDK provides software developers a simple way to measure the energy efficiency (greenness) of their Software by exposing the necessary and basic measurements made by Yokogawa’s highly accurate and reliable Power Analyzers.
Learn More
Evaluation of Lighting Devices Simultaneous measurement of voltage, current, and THD (distortion factor Learn More
Harmonic measurements Harmonic measurements Learn More
Measurement of Inverter Efficiency Measuring efficiency with high precision: simultaneous measurement of input and output
Learn More
Measurement of Power Consumption in Mobile Phones

Measurement of Power Consumption in Mobile Phones 


Learn More
Measuring Conversion Efficiency of Power Conditioner Measuring Conversion Efficiency of Power Conditioner Learn More
Reference equipment for power calibration Reference equipment for power calibration Learn More
Name Description  
761922 Harmonic Analysis Software for WT3000 (Learn More) The measurement procedures and settings for harmonic/flicker standards testing have been precisely defined. Learn More
LabVIEW Drivers for WT3000 LabVIEW drivers for WT3000 y-Link
Power Consumption Measuring Software For use with WT3000, WT1800,WT1600*1, WT500, WT210*1 and WT310. Conforms to IEC62301 Ed2.0(2011) and EN 50564:2011 testing methods.   *1 The WT1600 and WT210 discontinued sales y-Link
TMCTL TMCTL is a DLL to support development of custom software. By using this DLL, users can write original programs to control instruments from a PC. y-Link
USB Driver The USB Driver is needed when required by the software. y-Link
WT File Reader for WT500/WT1600/WT1800/WT3000 This software allows you to display data saved in WT500/WT1600/WT1800/WT3000 on your PC and change it to .csv format. y-Link
WT3000 Sample Program - Visual Basic This is a Visual Basic sample program of GP-IB/RS232/Ethernet/USB for WT3000 y-Link
WT3000 Sample Program - Visual Basic net This is a Visual Basic net sample program of GP-IB/RS232/Ethernet/USB for WT3000 y-Link
WT3000 Sample Program - Visual C# This is a Visual C# program of GP-IB/RS232/Ethernet/USB for WT3000 y-Link
WT3000 Sample Program - Visual C++ This is a Visual Basic C++ program of GP-IB/RS232/Ethernet/USB for WT3000 y-Link
WTViewer 760122 - Update WTViewer acquires numeric, waveform, and harmonic data from the WT3000/WT1800/WT500 Digital Power Analyzer via Ethernet, GP-IB or serial communications (RS-232). Learn More

BNC Cable 366924

BNC Cable 366924

BNC-BNC 1m. For connection to simultaneously measurement with 2 units, or for input external trigger signal. 

BNC cable 366925

BNC cable 366925

BNC-BNC 2m. For connection to simultaneously measurement with 2 units, or for input external trigger signal.

Measurement lead set 758917

Measurement lead set 758917

A set of 0.8m long red and black test leads, used in combination with a pair of optional 758922 or 758929 alligator-clip adapters. Appliable for DL750/DL750P & SL1400.

Fork terminal adapter 758921

Fork terminal adapter 758921

Adapters for fitting a 4mm banana plug to a fork terminal. Set contains one black and one red clip. 1000 Vrms-CAT II.

Small Alligator-clip Adapter 758922

Small Alligator-clip Adapter 758922

Rated at 300 V. Attaches to the 758917 test leads. Sold in pairs.
Applicable for DL750/DL750P, SL1000, SL1400

Safety Terminal Adapter Set 758923

Safety Terminal Adapter Set 758923

Two adapters in a set (spring-hold type).

Conversion Adapter 758924

Conversion Adapter 758924

For conversion between BNC and female banana plug
Applicable for DL750/DL750P, SL1000 & SL1400.

Large Alligator-clip Adapter 758929

Large Alligator-clip Adapter 758929

Rated at 1000V. Attaches to the 758917 test leads. Sold in pairs.
Applicable for DL750/DL750P, SL1000, SL1400.

B9284LK External Sensor Cable

B9284LK External Sensor Cable

For connection the external input of the WT3000 to the current sensor.
Length: 50cm



Printer Paper Roll
Thermal paper (10m) for WT1600, WT3000 - 1 roll


All Products Guide
All Products Guide
PDF (10.26 MB)
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