Yokogawa WT500 Mid-Range Power Analyzer

Yokogawa WT500 Mid-Range Power Analyzer

Product Overview:

The WT500 Power Analyzer is a Mid Range product for single-phase and three-phase power measurements. It is designed into a compact half-rack size chassis which can also be double rack mounted. Standard features include a color TFT display and USB interface for communications and memory. The instrument has a basic accuracy of 0.1%, maximum inputs of 1000 Vrms, 40 Arms and a measurement bandwidth of DC to 100 kHz.

What's New
  • Released firmware Version 1.12


- Simultaneous measurement of voltage, current, power, and harmonics
-  High-speed data updating (100 ms)
-  Display of numerical values, waveforms and trends
-  Measurement of bought and sold watt hours
-  Easy setup and operation


Current range: 0.5 to 40 A

Voltage range: 15 to 1000 V

Basic Power Accuracy: 0.1%

frequency range: DC 0.5 Hz to 100 kHz


Key layout offers intuitive control

  1. Cursor Keys

    Cursor keys can be used to move the on-screen cursor in four different directions. The cursor keys and SET key can also be used for making selections in soft menus. The WT500's menu structure is even more user-friendly than other models.
  2. RANGE Keys

    The RANGE keys can be used to set the voltage and current ranges. Quick intuitive range control is available by using direct keys.
  3. DISPLAY Keys

    DISPLAY keys can be used to switch between numerical values, waveforms, and other displays. The display format can easily be changed.
  4. SETUP Key

    The SETUP key can be used to enter various settings required for power measurement such as the wiring method and filters.
  5. FILE, IMAGE, and STORE Keys

    The keys related to data storage are located in the same area. Data can be easily stored to USB memory.
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Swfbuttonsm 1


  • Simultaneous measurement of DC and AC signals

    Evaluation of DC/AC signal conversion technology is critical in the renewable energy market. With input from 2 or more elements, the WT500 can measure DC and AC signals simultaneously and calculate input-to-output efficiency.
  • Separate integration functions for charge/discharge and bought/sold power

    The WT500 is equipped with integration functions that can not only evaluate charge and discharge current such as from secondary cells, but also bought and sold power in photovoltaic power generation systems.
  • Saving measured data directly to USB memory

    Measured data can be saved in CSV format directly to USB memory.
  • Easy setup with cursor keys

    Menu-type screen offers intuitive setting.
  • Simultaneous measurement of normal data and harmonic data with the harmonic measurement, /G5 option

    RMS voltage, RMS current, power values, and harmonic components up to the 50 order can be measured simultaneously.
  • WT series for power evaluation of energy-saving equipment 

    The WT series have been used as powermeters for Green IT, Energy Star, CO2 reduction and other energy-saving equipment. The WT series-Including the WT500--supports your power evaluation needs.

Newly Designed Architecture

Tm Wt500 03Intuitive control by using cursor keys in four different directions.

To reduce setting errors, menus display settings in order of relative importance in order.


Measured Value Direct Save Function

Tm Wt500 04Two USB ports for peripherals are installed for direct data saving (up to 1 G byte) in USB memory at shortest intervals. The saved data can be opened in applications such as Excel.

* Excel is a registered trademark of Microsoft Corporation in the U.S.A.


A Variety of Display Formats

Tm Wt500 05In addition to numerical data, the WT500 can display input signal waveforms and trends (time variation of numerical data).  Bar graph display and vector display are also available with the harmonic measurement (/G5) option.

*1 Waveforms of up to approximately 5 kHz can be displayed.

*2 Excludes single-phase models.

Split screen display for numerical values and waveforms is not available.


Simple Setting and Display of Efficiency

Two efficiency calculations can be set by selecting input elements or output elements from a list. Example: η1 = PΣ/P1 x 100%

η2 = PΣ/P2 x 100%

USB Memory Storage Function

Tm Wt500 06Only necessary items within the measured data like voltage, current, and power can be saved in USB memory in binary or CSV format (up to 1 GB).

Files saved in CSV format can be opened in general-purpose applications such as Excel to allow displaying of data in graphs.


Variety of Integration Functions

Tm Wt500 07In addition to integration functions of active power (WP), current (q), reactive power (WQ), and apparent power (WS), a new feature provides measurement of bought and sold watt hours. Also, average 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. Average active power is calculated by using user-defined settings.


GP-IB Communication (/C1)

 GP-IB communication enables you to control the WT500 or transfer data from a PC.

Ethernet Communication (/C7)

Tm Wt500 17Data can be transferred via Ethernet*communication.

It enables file transfers using an FTP server.

* 100BASE-TX


External Current Sensor Input (/EX1, /EX2, /EX3)

Current can be measured by using current clamps without disconnecting power supply wiring (voltage output type). By setting an external current sensor conversion ratio, it can support various types of current clamp-on probes.

VGA Output (/V1)

By connecting to a monitor, you can create large displays of numerical values and waveforms. This function is convenient for simultaneously confirming data on multiple monitors, or to check data remotely.

Harmonic Measurement (/G5)

This function enables simultaneous measurement of normal and harmonic data. Harmonic components of up to the 50th order can be measured. With the WT500 you can simultaneously confirm voltage, current, and the distortion factor (THD) as well as measure the distortion factor without switching modes.

Tm Wt500 18   Tm Wt500 19
Harmonic Dual List   THD measurement

Delta Computation (/DT)

This function allows you to calculate individual phase voltages and phase currents from the line voltages and phase currents measured in a three-phase, three-wire (3P3W) system. The phase voltage can be calculated from the line voltage measured with the three-phase, three-wire (3V3A) method. This is useful when you want to determine the phase voltage in a DUT with no neutral line by using the three-phase, three-wire (3V3A) method.

Note: This function cannot be installed on products with only one element.

Added Frequency Measurement (/FQ)

In addition to the standard two channels of frequency measurement, an option is available for frequency measurement on all channels. This option provides frequency measurement of voltage and current on all channels with input elements 1 through 3 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.

Note: This function cannot be installed on products with only one input element.



Rear Panel

Tm Wt500 20

  1. Standard feature
  2. Voltage input terminals
  3. Current input terminals
  4. USB communication interface
  5. External trigger Signal, External clock input Connector

  6. Optional feature
  7. External Current Sensor Input Terminals (/EX option)
  8. GP-IB communication Interface (/C1 option)
  9. Ethernet Port (/C7 option)
  10. VGA Output (/V1 option)


Example of basic characteristics showing the WT500's high precision

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Connection Diagram

Connection for the Measurement Cables and Adapters

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Product Part no. Specifications Order quantity
Output connector B8200JQ D-SUB 9-pin, with 2 screws 1
Load resistors B8200JR   10 Ω, 0.25 W x 4

Connect 4 in parallel to set resistance to 2.5 Ω.   


Connection Diagram for Clamp-on Probe

Tm Wt500 30 1 1

*Don't connect and use the current input terminal and EXT terminal simultaneously.



Instruction Manual



Application Notes

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
Measuring Power Bought and Sold via Power Conditioners These days people are talking about the problem of energy depletion, and the industry is turning more and more toward stricter energy savings policies and the use of renewable energy. Learn More
Evaluation and Efficiency Measurements of AC Adaptors and Other Products with and without Loads To evaluate AC adaptors, engineers must acquire the voltage. Learn More
Performance Evaluation and Testing of Home Electronics Prevention of global warming has become an issue in recent years, and industry is turning more and more toward stricter energy savings policies and the use of renewable energy. Learn More
Measuring Power Conversion Efficiency and Power Consumption in a Photovoltaic Generator Photovoltaic power generation has gained attention in recent years, largely due to a new sense of urgency regarding the prevention of global warming. Learn More
Measuring Fluctuations in Voltage, Current, Power, and Frequency of a Wind Power Generator Wind power is a renewable energy source that is being aggressively promoted (particularly in Europe) in order to reduce emissions of the greenhouse gasses that are responsible for global warming Learn More
Large Current Measurements for IH Cooking Heaters In recent years the buzzword "all electric" is becoming popular, which refers to kitchen appliances, water heaters, and other devices in the home all being supplied with electric power. Learn More


Name Description  
LabVIEW Drivers for WT500 LabVIEW drivers for WT500 y-Link
Power Consumption Measuring Software For use with WT3000/WT3000E, WT1800,WT1600*¹, WT500, WT210*¹, WT310 and WT310E. Conforms to IEC62301 Ed2.0(2011) and EN 50564:2011 testing methods.
*¹ The WT1600 and WT210 discontinued sales
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
TMCTL (DLTOOL) - 160 This API lets you control the DL9000 series from an external program or to transfer the DL9000 series' data to the external program. The API is available as a Windows DLL and can be accessed from your program. 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/WT3000E on your PC and change it to .csv format. y-Link
WT500 Sample Program - Visual Basic This is a Visual Basic sample program of GP-IB, Ethernet and USB for WT500 y-Link
WT500 Sample Program - Visual Basic net This is a Visual Basic net sample program of GP-IB, Ethernet and USB for WT500 y-Link
WT500 Sample Program - Visual C# This is a Visual C# program of GP-IB, Ethernet and USB for WT500 y-Link
WT500 Sample Program - Visual C++ This is a Visual Basic C++ program of GP-IB, Ethernet and USB for WT500 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