YOKOGAWA WT1600 User Manual

Digital Power Meter

Advanced Test Equipment Rentals

www.atecorp.com 800-404-ATEC (2832)

IM 760101-01E

4th Edition

Product Registration

Thank you for purchasing YOKOGAWA products.

YOKOGAWA provides registered users with a variety of information and services. Please allow us to serve you best by completing the product registration form accessible from our homepage.

http://www.yokogawa.com/tm/

PIM 103-01E

Notes

Thank you for purchasing the YOKOGAWA WT1600 Digital Power Meter. This user’s manual contains useful information about the functions, operating procedures, and handling precautions of the instrument. To ensure correct use, please read this manual thoroughly before beginning operation. After reading the manual, keep it in a convenient location for quick reference whenever a question arises during operation. The following two manuals, including this one, are provided as manuals for the WT1600. Read them along with this manual.

Manual Title Manual No. Description

WT1600 Digital Power Meter IM 760101-01E This manual. Explains all functions and User’s Manual procedures of the WT1600 excluding

the communication functions.

WT1600 Digital Power Meter IM 760101-11E Explains the communication functions Communication Interface of the GP-IB, RS-232, and Ethernet User’s Manual interfaces.

• The contents of this manual are subject to change without prior notice as a result of continuing improvements to the instrument’s performance and functions. The figures given in this manual may differ from the actual screen.

• Every effort has been made in the preparation of this manual to ensure the accuracy of its contents. However, should you have any questions or find any errors, please contact your nearest YOKOGAWA dealer.

• Copying or reproducing all or any part of the contents of this manual without the permission of Yokogawa Electric Corporation is strictly prohibited.

• The TCP/IP software of this product and the document concerning the TCP/IP software have been developed/created by YOKOGAWA based on the BSD Networking Software, Release 1 that has been licensed from California University.

Trademarks

• MS-DOS is either a registered trademark or trademark of Microsoft Corporation in the United States and/or other countries.

• Adobe, Adobe Acrobat, and PostScript are registered trademarks or trademarks of Adobe Systems Incorporated.

• Zip is either a registered trademark or trademark of Iomega Corporation in the United States and/or other countries.

• For purposes of this manual, the TM and ® symbols do not accompany their respective trademark names or registered trademark names.

• Other company and product names are trademarks or registered trademarks of their respective companies.

Revisions

• First edition: June 2001

• Second edition: August 2001

• Third edition: December 2002

• Fouth edition: April 2004

IM 760101-01E

Checking the Contents of the Package

Unpack the box and check the contents before operating the instrument. If some of the contents are not correct or missing or if there is physical damage, contact the dealer from which you purchased them.

WT1600

Check that the model name and suffix code given on the name plate on the side panel match those on the order.

MODEL SUFFIX

NO.

Made in Japan

MODEL SUFFIX

NO.

Made in Japan

MODEL and SUFFIX Codes

Model Suffix Code Description

760101 100-120 / 200-240 VAC

For details on the construction of the current input terminal that is equipped on the instrument, see the next section.

Current input terminal Element 123456 Construction

-01 50 A –––––

-02 50 A 50 A – – – –

-03 50 A 50 A 50 A – – –

-04 50 A 50 A 50 A 50 A – –

-05 50 A 50 A 50 A 50 A 50 A –

-06 50 A 50 A 50 A 50 A 50 A 50 A

-10 5 A –––––

-11 5 A 50 A – – – –

-12 5 A 50 A 50 A – – –

-13 5 A 50 A 50 A 50 A – –

-14 5 A 50 A 50 A 50 A 50 A –

-15 5 A 50 A 50 A 50 A 50 A 50 A

-20 5 A 5 A– – – –

-21 5 A 5 A 50 A – – –

-22 5 A 5 A 50 A 50 A – –

-23 5 A 5 A 50 A 50 A 50 A –

-24 5 A 5 A 50 A 50 A 50 A 50 A

-30 5 A 5 A5 A– – –

-31 5 A 5 A 5 A 50 A – –

-32 5 A 5 A 5 A 50 A 50 A –

-33 5 A 5 A 5 A 50 A 50 A 50 A

-40 5 A 5 A5 A5 A– –

-41 5 A 5 A5 A5 A50 A–

-42 5 A 5 A 5 A 5 A 50 A 50 A

-50 5 A 5 A5 A5 A5 A–

-51 5 A 5 A5 A5 A5 A50 A

-60 5 A 5 A5 A5 A5 A5 A

Communication interface -C1 GP-IB Interface (Either one is built in.) -C2 Serial (RS-232) interface

ii IM 760101-01E

Checking the Contents of the Package

Suffix Code Description

Power cord -D UL/CSA Standard power cord (Part No.: A1006WD)

-F VDE Standard Power Cord (Part No.: A1009WD)

-Q BS Standard Power Cord (Part No.: A1054WD)

-R AS Standard Power Cord (Part No.: A1024WD)

Options /B5 Built-in printer

/C7 SCSI /C10 SCSI, Ethernet interface, and internal hard disk. /DA D/A output (30 channels) /MTR Motor evaluation function (Either /C7 or /C10 can be added)

Example of specifications and suffix code

Ex: 5-A input terminals in elements 1 through 3, 50-A input terminals in elements 4 through 6, GP-IB interface, UL/CSA standard power cord, built-in printer, and SCSI → 760101-33-C1-D/ B5/C7

[Maximum rated voltage: 125 V; Maximum rated current: 7 A]

[Maximum rated voltage: 250 V; Maximum rated current: 10 A]

[Maximum rated voltage: 240 V; Maximum rated current: 10 A]

NO. (Instrument No.)

When contacting the dealer from which you purchased the instrument, please quote the instrument No.

IM 760101-01E

iii

Checking the Contents of the Package

Standard Accessories

The following are supplied with the instrument.

Part Name Part Number Q’ty Notes

1. Power cord See the previous table. 1 –

2. Spare power fuse A1354EF 1 250 V, 6.3 A, time lag

3. Printer roll paper B9316FX 2 For the built-in printer

4. Rubber feet A9088ZM 2 Two pieces in one set.

5. 36-pin connector A1005JD 1 For D/A output

6. Current input protective cover B9316BX 1 With 4 attachment screws, part

7. • User’s Manual IM760101-01E 1 This manual

• Communication Interface IM760101-11E 1 – User’s Manual

1. (One of the following power cords is supplied according to the instrument's suffix codes.)

(attached to the fuse holder)

Provided only with option /B5

Two sets provided.

Provided only with option /DA

number B9946GZ.

6. 7.5.

iv IM 760101-01E

Optional Accessories (Sold Separately)

The following optional accessories are available for purchase separately.

Part Name Part Number Q’ty Notes

1. Serial port adapter 366971 1 9 pin*1-25 pin*2adapter

2. BNC-alligator clip 366926 1 42 V or less, length 1 m

3. BNC-BNC 366924 1 42 V or less, length 1 m measurement lead 366925 1 42 V or less, length 2 m

4. External sensor cable B9284LK 1 For connecting the current sensor

5. Measurement lead 758917 1 Two leads in one set, used with

6. Alligator clip adapter set 758922 1 Two pieces in one set, for the

7. Alligator clip adapter set 758929 1 Two pieces in one set, for the

8. Fork terminal adapter set 758921 1 Two pieces in one set, for the

Checking the Contents of the Package

*1 EIA-574 Standard *2 EIA-232 Standard (RS-232)

measurement lead

input connector of the WT1600 Length 0.5 m

the separately sold 758922 or 758929 adapter, length 0.75 m, ratings 1000 V

758917 measurement lead. Rated voltage 300 V

758917 measurement lead. Rated voltage 1000 V

758917 measurement lead. Rated current 25 A

Spare Parts (Sold Separately)

The following spare parts are available.

Part Name Part Number Q’ty Notes

1. Printer roll paper B9316FX 10 One roll is one set, thermal-

2. Power fuse A1354EF 2 250 V, 6.3 A, time lag

3. 4.

sensitive paper, total length 10 m

IM 760101-01E

Safety Precautions

This instrument is an IEC safety class I instrument (provided with terminal for protective earth grounding). The general safety precautions described herein must be observed during all phases of operation. If the instrument is used in a manner not specified in this manual, the protection provided by the instrument may be impaired. Yokogawa Electric Corporation assumes no liability for the customer’s failure to comply with these requirements.

The following symbols are used on this instrument.

“Handle with care.” (To avoid injury, death of personnel or damage to the instrument, the operator must refer to the explanation in the User’s Manual or Service Manual.)

Electric shock, danger

Alternating current

Both direct and alternating current

ON(power)

OFF(power)

In-position of a bistable push control

Out-position of a bistable push control

Ground

vi IM 760101-01E

Safety Precautions

Make sure to comply with the precautions below. Not complying might result in injury or death.

WARNING

Power Supply

Ensure that the source voltage matches the voltage of the power supply before turning ON the power.

Power Cord and Plug

To prevent the possibility of electric shock or fire, be sure to use the power cord supplied by YOKOGAWA. The main power plug must be plugged into an outlet with a protective earth terminal. Do not invalidate this protection by using an extension cord without protective earth grounding.

Protective Grounding

Make sure to connect the protective earth to prevent electric shock before turning ON the power.

Necessity of Protective Grounding

Never cut off the internal or external protective earth wire or disconnect the wiring of the protective earth terminal. Doing so poses a potential shock hazard.

Defect of Protective Grounding

Do not operate the instrument if the protective earth or fuse might be defective. Also, make sure to check them before operation.

Fuse

To avoid the possibility of fire, only use a fuse that has a rating (voltage, current, and type) that is specified by the instrument. When replacing a fuse, turn OFF the power switch and unplug the power cord. Never short the fuse holder.

Do Not Operate in an Explosive Atmosphere

Do not operate the instrument in the presence of flammable liquids or vapors. Operation in such environments constitutes a safety hazard.

Do Not Remove Covers

The cover should be removed by YOKOGAWA’s qualified personnel only. Opening the cover is dangerous, because some areas inside the instrument have high voltages.

External Connection

Securely connect the protective grounding before connecting to the item under measurement or an external control unit.

IM 760101-01E

vii

How to Use This Manual

Structure of the Manual

This user’s manual consists of the following sections.

Chapter 1 Explanation of Functions

Describes the functions of the instrument. Operating procedures are not given in this chapter. However, reading this chapter will help you understand the operating procedures given in the chapters that follow.

Chapter 2 Names and Uses of Parts

Describes the names and uses of each part of the instrument.

Chapter 3 Before Starting Measurements

Describes precautions for the use of the instrument, how to install the instrument, how to connect to the power supply, how to wire measurement circuits, how to turn ON/OFF the power switch, and other preparations before starting measurements.

Chapter 4 Screen Display Format

Describes how to display numerical data, waveforms, bar graphs, vectors, and trends, the mixed display, and the meaning of each displayed item.

Chapter 5 Measurement Conditions

Describes how to set the input conditions for the measured voltage/current signal and the handling of the input signal such as the wiring system, the measurement range, the filter, averaging, data update rate, and the crest factor.

Chapter 6 Normal Measurement and Integration

Describes how to set the displayed items of numerical data during normal measurement, how to set the computing equation, and how to set integration.

Chapter 7 Harmonic Measurement

Describes how to set the displayed item of numerical data, the PLL source, the order of analysis, the computing equation, the bar graph, and the vector display during harmonic measurement.

Chapter 8 Motor Evaluation (Option)

Describes how to set the instrument in order to determine the motor characteristics by inputting signals from revolution sensors and torque meters.

Chapter 9 Waveform Display

Describes how to display the waveforms of the voltage and current signals.

Chapter 10 Trend Display

Describes how to display the trend.

Chapter 11 Storing and Recalling Data and Saving the Stored Data

Describes how to store and recall the data and how to save the stored data.

Chapter 12 Saving and Loading the Data

Describes how to save setup parameters, waveform display data, numerical data, and screen image data and how to load the saved data to the instrument.

Chapter 13 Ethernet Communications (Option)

Describes how to mutually transfer files containing setup parameters, waveform display data, and numerical data with PCs and workstations that are on the network using the Ethernet interface.

Chapter 14 Built-in Printer (Option)

Describes how to output numerical data and screen image to the built-in printer.

Chapter 15 D/A Output and Other Functions

Describes how to set the D/A output and other functions.

Chapter 16 Troubleshooting, Maintenance, and Inspection

Describes the possible causes of problems and their appropriate corrective measures. Describes the messages that are displayed on the screen. Describes maintenance and inspection issues such as how to perform self-tests and replace power fuses.

Chapter 17 Specifications

Summarizes the specifications of the instrument in tables.

Appendix

Describes how to determine the measurement function and delta computation. Gives a list of initial settings. Describes the ASCII header file format.

Index

Alphabetic and symbol index of contents.

viii IM 760101-01E

Conventions Used in This Manual

Unit

k: Denotes 1000. Example: 15 kg, 100 kHz K: Denotes 1024. Example: 640 KB (Storage capacity of floppy disks)

Displayed Characters

Bold characters used in the procedural explanations indicate characters that are displayed on the panel keys for the respective procedure or the characters on the screen. SHIFT+key means you will press SHIFT to turn ON the indicator that is located above and to the left of SHIFT followed by the operation key. The menu written below the pressed key appears on the screen.

Symbols

The following symbols are used in this manual.

How to Use This Manual

Improper handling or use can lead to injury to the user or damage to the instrument.

indicate that the user must refer to the user’s manual for special instructions. The same symbol appears in the corresponding place in the user’s manual to identify those instructions. In the manual, the symbol is used in conjunction with the word “WARNING” or “CAUTION.”

This symbol appears on the instrument to

WARNING

CAUTION

Note

Symbols Used on Pages Describing Operating Procedures

On pages that describe the operating procedures in Chapter 3 through 16, the following symbols are used to distinguish the procedures from their explanations.

Keys

Procedure

Explanation

Describes precautions that should be observed to prevent injury or death to the user.

Describes precautions that should be observed to prevent minor or moderate injury, or damage to the instrument.

Provides important information for the proper operation of the instrument.

Indicates the key related to the operation.

Follow the steps indicated with numbers. The procedures are given with the premise that the user is carrying out the steps for the first time. Depending on the operation, not all steps need to be taken.

This section describes the setup parameters and the limitations regarding the procedures. It does not give a detailed explanation of the function. For details on the function, see chapter 1.

IM 760101-01E

Checking the Contents of the Package ...........................................................................................ii

Safety Precautions .........................................................................................................................vi

How to Use This Manual .............................................................................................................. viii

Chapter 1 Explanation of Functions

1.1 System Configuration and Block Diagram ....................................................................... 1-1

1.2 Measurement Function and Measurement Period ........................................................... 1-3

1.3 Measurement Conditions ................................................................................................. 1-9

1.4 Numeric Display ............................................................................................................. 1-14

1.5 Computation................................................................................................................... 1-18

1.6 Integration ...................................................................................................................... 1-20

1.7 Waveform Display .......................................................................................................... 1-23

1.8 Bar Graphs, Vectors, and Trend Displays ...................................................................... 1-29

1.9 Saving and Loading Data and Other Functions ............................................................. 1-32

Chapter 2 Names and Uses of Parts

2.1 Front Panel, Rear Panel, and Top View ........................................................................... 2-1

2.2 Operation Keys, Jog Shuttle ............................................................................................ 2-3

Chapter 3 Before Starting Measurements

3.1 Precautions Concerning the Use of the Instrument ......................................................... 3-1

3.2 Installing the Instrument ................................................................................................... 3-2

3.3 Wiring Precautions ...........................................................................................................3-4

3.4 For Making Accurate Measurements ............................................................................... 3-6

3.5 Connecting the Power Supply.......................................................................................... 3-8

3.6 Directly Wiring the Circuit under Measurement ............................................................... 3-9

3.7 Using an External Current Sensor to Wire the Circuit under Measurement .................. 3-12

3.8 Using an External PT or CT to Wire the Circuit under Measurement ............................ 3-16

3.9 Wiring a Circuit with Voltage Input Exceeding 600 V ..................................................... 3-19

3.10 Turning ON/OFF the Power Switch................................................................................ 3-20

3.11 Setting the Date and Time ............................................................................................. 3-22

3.12 Entering Values and Strings........................................................................................... 3-24

Chapter 4 Screen Display Format

4.1 Displaying the Data (Numerical Data) of Measurement Functions .................................. 4-1

4.2 Displaying Waveforms ................................................................................................... 4-10

4.3 Displaying Bar Graphs ................................................................................................... 4-12

4.4 Displaying Vectors ......................................................................................................... 4-14

4.5 Displaying Trends .......................................................................................................... 4-15

4.6 Listing the Setup Parameters......................................................................................... 4-17

Chapter 5 Measurement Conditions

5.1 Selecting the Wiring System ............................................................................................ 5-1

5.2 Setting the Measurement Range during Direct Input ....................................................... 5-4

5.3 Setting the Measurement Range When Using an External Current Sensor .................. 5-10

5.4 Setting the Scaling Function When Using an External PT or CT ................................... 5-14

5.5 Selecting the Input Filter ................................................................................................ 5-17

5.6 Averaging ....................................................................................................................... 5-19

5.7 Changing the Data Update Rate .................................................................................... 5-22

x IM 760101-01E

5.8 Holding the Display and Performing Single Measurements........................................... 5-24

5.9 Holding the Numerical Data Display at the Maximum .................................................... 5-25

5.10 Performing Master/Slave Synchronized Measurements ................................................ 5-26

5.11 Selecting the Crest Factor ............................................................................................. 5-29

Chapter 6 Normal Measurement and Integration

6.1 Changing the Displayed Item of Numerical Data ............................................................. 6-1

6.2 Setting the Measurement Period ..................................................................................... 6-4

6.3 Selecting the Frequency Measurement Target ................................................................ 6-7

6.4 Setting the User-Defined Function ................................................................................... 6-8

6.5 Setting the Delta Computation ....................................................................................... 6-12

6.6 Setting the Equations for Apparent Power and Corrected Power .................................. 6-15

6.7 Selecting the Display Format of the Phase Difference .................................................. 6-18

6.8 Setting the Normal Integration Mode and the Integration Timer .................................... 6-20

6.9 Setting the Real-time Integration Mode, the Integration Timer, and the

Reservation Time ........................................................................................................... 6-23

6.10 Selecting the Current Mode for Current Integration and ON/OFF of Integration Auto

Calibration ......................................................................................................................6-29

6.11 Performing Integration (Start, Stop, and Reset)............................................................. 6-31

Contents

Chapter 7 Harmonic Measurement

7.1 Setting the Harmonic Measurement Mode ...................................................................... 7-1

7.2 Changing the Displayed Item of Numerical Data ............................................................. 7-2

7.3 Selecting the Measurement Target .................................................................................. 7-7

7.4 Selecting the PLL Source................................................................................................. 7-8

7.5 Setting the Harmonic Order to Be Analyzed .................................................................. 7-11

7.6 Selecting the Equation for the Distortion Factor ............................................................ 7-13

7.7 Changing the Data Length ............................................................................................. 7-14

7.8 Setting the User-Defined Function ................................................................................. 7-15

7.9 Changing the Display Items of Bar Graphs and Performing Cursor Measurements ..... 7-19

7.10 Changing the Vector Display.......................................................................................... 7-23

Chapter 8 Motor Evaluation (Option)

8.1 Inputting Signals of Rotating Speed and Torque.............................................................. 8-1

8.2 Selecting the Input Range of the Revolution and Torque Signals and the Synchronization

Source .............................................................................................................................. 8-3

8.3 Selecting the Line Filter ................................................................................................... 8-6

8.4 Setting the Scaling Factor, the Pulse Count, and Unit Used to Measure the Rotating

Speed ............................................................................................................................... 8-7

8.5 Setting the Scaling Factor and Unit Used to Measure the Torque ................................. 8-10

8.6 Setting the Motor’s Number of Poles Used to Compute the Synchronous Speed and the

Slip ................................................................................................................................. 8-12

8.7 Setting the Scaling Factor and Unit Used to Compute the Motor Output ...................... 8-14

8.8 Computing the Motor Efficiency and Total Efficiency ..................................................... 8-16

Chapter 9 Waveform Display

9.1 Retrieving Waveform Display Data .................................................................................. 9-1

9.2 Setting the Time Axis ....................................................................................................... 9-2

9.3 Setting the Trigger............................................................................................................ 9-4

9.4 Zooming Vertically and Moving the Vertical Position ....................................................... 9-8

9.5 Turning ON/OFF the Waveform Display ........................................................................ 9-11

9.6 Splitting the Screen and Displaying Waveforms ............................................................ 9-13

App

IM 760101-01E

Index

Contents

9.7 Interpolating the Display and Changing the Graticule.................................................... 9-16

9.8 Turning ON/OFF the Scale Value and Waveform Label ................................................ 9-19

9.9 Performing Cursor Measurements ................................................................................. 9-21

Chapter 10 Trend Display

10.1 Retrieving Trend Display Data ....................................................................................... 10-1

10.2 Selecting the Trend Display Target ................................................................................ 10-2

10.3 Turning ON/OFF the Trend Display ............................................................................... 10-6

10.4 Splitting the Screen and Displaying Trends ................................................................... 10-8

10.5 Setting the Time Axis ................................................................................................... 10-10

10.6 Setting the Scale .......................................................................................................... 10-12

10.7 Performing Cursor Measurements ............................................................................... 10-14

10.8 Restarting the Trend .................................................................................................... 10-18

Chapter 11 Storing and Recalling Data and Saving the Stored Data

11.1 Setting the Store Mode .................................................................................................. 11-1

11.2 Setting the Store Count, the Store Interval, and the Store Reservation Time................ 11-3

11.3 Setting the Numerical Data and Waveform Display Data to Be Stored ......................... 11-6

11.4 Storing the Data ........................................................................................................... 11-10

11.5 Saving the Stored Data ................................................................................................ 11-13

11.6 Recalling the Stored Data ............................................................................................ 11-20

Chapter 12 Saving and Loading the Data

12.1 Precautions to Be Taken When Using the Floppy Disk Drive ........................................ 12-1

12.2 Built-in Hard Disk (Option) ............................................................................................. 12-2

12.3 Connecting a SCSI Device ............................................................................................ 12-3

12.4 Changing the SCSI ID Number ...................................................................................... 12-4

12.5 Formatting the Disk ........................................................................................................ 12-6

12.6 Saving Setup Parameters, Waveform Display Data, and Numerical Data................... 12-11

12.7 Saving Screen Image Data .......................................................................................... 12-20

12.8 Loading Setup Parameters .......................................................................................... 12-23

12.9 Specifying the File to Be Displayed, Viewing File Properties, and Changing the File

Attribute ........................................................................................................................ 12-26

12.10 Deleting Files ............................................................................................................... 12-29

12.11 Copying Files ............................................................................................................... 12-32

12.12 Renaming Directories and Files and Creating Directories ........................................... 12-36

Chapter 13 Ethernet Communications (Option)

13.1 Connecting the WT1600 to a PC ................................................................................... 13-1

13.2 Setting the Ethernet Interface (TCP/IP) ......................................................................... 13-2

13.3 Saving Setup, Waveform Display, Numerical, and Image Data to the FTP Server

(FTP Client Function) ..................................................................................................... 13-8

13.4 Outputting the Screen Image to a Network Printer ...................................................... 13-11

13.5 Sending E-mail Messages ........................................................................................... 13-15

13.6 Accessing the WT1600 from a PC or Workstation (FTP Server Function) .................. 13-19

13.7 Checking the Presence of the Ethernet Interface (Option) and the MAC address ...... 13-23

13.8 Setting the FTP Passive Mode and LPR/SMTP Timeout ............................................. 13-24

Chapter 14 Built-in Printer (Option)

14.1 Installing the Paper Roll and Paper Feeding ................................................................. 14-1

14.2 Printing Screen Images .................................................................................................. 14-5

14.3 Printing Numerical Data Lists and Bar Graphs .............................................................. 14-7

xii IM 760101-01E

Chapter 15 D/A Output and Other Functions

15.1 Setting the D/A Output (Option) ..................................................................................... 15-1

15.2 RGB Video Signal (VGA) Output ................................................................................... 15-9

15.3 Initializing the Settings ................................................................................................. 15-10

15.4 Performing Zero-Level Compensation ......................................................................... 15-12

15.5 Using the NULL Function ............................................................................................. 15-13

15.6 Selecting the Message Language and the Screen Brightness .................................... 15-14

15.7 Setting the Display Color of the Screen ....................................................................... 15-16

15.8 Setting Key Lock .......................................................................................................... 15-19

Contents

Chapter 16 Troubleshooting, Maintenance, and Inspection

16.1 Troubleshooting ............................................................................................................. 16-1

16.2 Error Messages and Corrective Actions......................................................................... 16-2

16.3 Performing a Self-Test ................................................................................................... 16-6

16.4 Checking the System Conditions ................................................................................... 16-8

16.5 Replacing the Power Fuse ............................................................................................. 16-9

16.6 Recommended Replacement Parts ............................................................................. 16-10

Chapter 17 Specifications

17.1 Input ............................................................................................................................... 17-1

17.2 Display ........................................................................................................................... 17-2

17.3 Measurement Functions (Items) during Normal Measurement...................................... 17-3

17.4 Measurement Functions (Items) during Harmonic Measurement .................................. 17-5

17.5 Accuracy ........................................................................................................................ 17-7

17.6 Functions ..................................................................................................................... 17-10

17.7 Input/Output of the Master/Slave Synchronization Signal............................................ 17-16

17.8 External Clock Input ..................................................................................................... 17-16

17.9 RGB Video Signal (VGA) Output ................................................................................. 17-17

17.10 Built-in Floppy Disk ...................................................................................................... 17-17

17.11 Built-in Hard Disk (Option) ........................................................................................... 17-17

17.12 SCSI (Option) ............................................................................................................... 17-17

17.13 Ethernet Interface (Option) .......................................................................................... 17-18

17.14 Built-in Printer (Option) ................................................................................................ 17-18

17.15 GP-IB Interface ............................................................................................................ 17-18

17.16 Serial (RS-232) Interface ............................................................................................. 17-19

17.17 General Specifications ................................................................................................. 17-19

17.18 External Dimensions .................................................................................................... 17-21

Appendix

Index

IM 760101-01E

Appendix 1 Symbols and Determination of Measurement Functions .................................. App-1

Appendix 2 Determination of Delta Computation ................................................................. App-6

Appendix 3 List of Initial Settings and Display Order of Numerical Data ............................. App-8

Appendix 4 ASCII Header File Format ...............................................................................App-14

Appendix 5 Power Basics

(Power/Harmonics/Three Constants Related to the AC Circuit) ..................... App-17

xiii

App

Index

Chapter 1 Explanation of Functions

1.1 System Configuration and Block Diagram

System Configuration

Numerical data

Waveform display data

Screen image data

Stored data

Setup parameters

Explanation of Functions

Outputs measured values using analog voltage

External SCSI device

External clock input

Master/slave

sync signal

Revolution

sensor

RGB video signal (VGA) output

D/A output (option)

SCSI interface (option)

Setup parameters

Numerical data Waveform display data Screen image data Stored data

Measurement start Measurement stop

Motor evaluation (option)

Torque

meter

CRT

Image signal

element

Voltage

(Input either one)

Numerical data Waveform display data Screen image data Stored data

Setup parameters

Ethernet (option) interface

GP-IB/serial* interface

Setup parameters

Input

Current

(Input any one)

Printer

Numerical data

Waveform display data

Setup parameters

Floppy disk

Numerical data Waveform display data Screen image data and stored data

Built-in printer (option)

Prints screen image/ numerical data list

Internal memory

Stores numerical data/ waveform display data Recalls numerical data/waveform display data

Built-in hard disk (option)

Saves stored data, Saves setup parameters/ numerical data/ waveform display data/ screen image data

IM 760101-01E

Item under measurement

* Conforms to EIA-574 (9-pin EIA-232(RS-232)).

Current sensor

1-1

1.1 System Configuration and Block Diagram

Block Diagram

ELEMENT2~6

ELEMENT1

Line Filter

EXT

Zero Cross Filter

A/D

ZERO DET.

PEAK DET.

A/D

ZERO DET.

PEAK DET.

DSP

CPU

CPU G.A

ROM

DRAM

SRAM

Display

G.A

”

6.4 LCD

KEY&

LED

GP-IB

Serial

PRINTER (option)

SCSI

(option)

TORQUE

SPEED

MOTOR(option)

ZERO DET.

PHOTO

ISO. PEAK DET.

HDD

(option)

I/O

D/A

(option)

10BASE-T

(option)

Line Filter

COUNTER

A/D

PEAK DET.

A/D

RTC

DSP

PLL

FDD

Signal Flow and Process

The input circuits, Elements 1 through 6, consist of a voltage input circuit and a current input circuit. The input circuits are mutually isolated. They are also isolated from the case.

The voltage signal that is applied to the voltage input terminal (U, ± ) is normalized using the voltage divider of the voltage input circuit and an operational amplifier (OP AMP). It is then isolated by the transformer and input to a voltage A/D converter. The current input circuit is equipped with two types of input terminals, a current input terminal (I, ± ) and a current sensor input connector (EXT). Either one can be used at any given time. The voltage signal from the current sensor that received the signal at the current sensor input connector is normalized using the voltage divider and an operational amplifier (OP AMP). It is then isolated by the transformer and input to a current A/D converter. The current signal that is applied to the current input terminal is converted to a voltage by a current divider. Then, it is input to the current A/D converter in the same fashion as the voltage signal from the current sensor.

During normal measurement, the voltage signal that is input to the voltage A/D converter or current A/D converter is converted to digital values at an interval of approximately 5 µs. The measured value is derived using a DSP based on the converted digital values. During harmonic measurement, the applied voltage signal is converted to digital values at an interval that is an integer multiple of the PLL source signal (cycle of the clock generated by the PLL circuit). The measured value of each item of harmonic measurement is derived by performing an FFT based on the converted digital values using a DSP.

The measured value is transmitted to the CPU. Various computed values are determined from the measured values. These measured values and computed values are displayed, output through a D/A output, or output through communications.

When waveform display data is not being retrieved during normal measurement, the DSP and CPU processes are pipelined, and the DSP process is executed in real-time. Therefore, measurements with few data dropouts can be achieved against the input signal.

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1.2 Measurement Function and Measurement Period

Types of Measurement Functions during Normal Measurement

The data (numerical data) of measurement functions during normal measurement is measured or computed from the sampled data*1 described later in “Measurement Period.”

*1 The WT1600 samples the instantaneous values of the voltage and current signals at a

specified sample rate*2. The sampled data is processed as numerical data or data used to display waveforms on the screen (waveform display data).

*2 Sample rate represents the number of data points that are sampled within 1 s. For example,

at a sample rate of 200 kS/s, 200000 data points are sampled every second.

• Types of Measurement Functions

• Measurement functions on each input element

The following 29 types of measurement functions are available. For details on the determination of each measurement function data, see appendix 1. U (voltage Urms, Umn, Udc, Uac), I (current Irms, Imn, Idc, Iac), P (active power), S (apparent power), Q (reactive power), λ (power factor), φ (phase difference), fU/fI (also expressed as fU: FreqU and fI: FreqI, measures the frequencies of up to three voltage/current signals), U+pk/U-pk (maximum/minimum values of voltage), I+pk/I-pk(maximum/minimum values of current), CfU/CfI(crest factor of voltage/ current), FfU/FfI (form factor of voltage/current), Z (impedance of the load circuit), Rs/Xs (resistance/reactance of the load circuit that has a resistor R, inductor L, and capacitor C connected in series), Rp/Xp (resistance/reactance of the load circuit that has a R, L, and C connected in parallel), Pc (Corrected Power)

Explanation of Functions

• Measurement functions of the average or sum of input elements (Σ functions)

The following 19 types of measurement functions are available. For details on the determination of each measurement function data, see appendix 1. UΣ (voltage average UrmsΣ, UmnΣ, UdcΣ, UacΣ), IΣ (current average IrmsΣ, ImnΣ, IdcΣ, IacΣ), PΣ (sum of active powers), SΣ (sum of apparent powers), QΣ (sum of reactive powers), λΣ (power factor average), φΣ (phase difference average), ZΣ (impedance average of the load circuit), RsΣ/XsΣ (average of the resistance/ reactance of the load circuit that has a R, L, and C connected in series), RpΣ/XpΣ (average of the resistance/reactance of the load circuit that has a R, L, and C connected in parallel), PcΣ (sum of Corrected Powers)

• Efficiency (Σ functions)

η (Efficiency 1), 1/η (Efficiency 2). See “Efficiency” on the next page.

• Measurement functions of integration

See section 1.6.

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1.2 Measurement Function and Measurement Period

Determining the Voltage and Current

There are four types of measurement functions for voltage (U) and current (I).

• Urms, Irms (true rms value)

These values are the true rms values of the voltage and current. The instantaneous values over one period are squared and averaged. Then, the square root of the value is determined. f(t) and T represent the input signal as a function of time and the period of the input signal, respectively.

Urms or Irms =

1 T

• Umn, Imn (rectified mean value calibrated to the rms value)

This function rectifies one period of the voltage or current signal, determines the average, and multiplies the result by a coefficient. The coefficient is a value that when applied to a sinusoidal input signal, gives the true rms value. When the input signal is a distorted or is a DC waveform, these values will differ from the true rms values. f(t) and T represent the input signal as a function of time and the period of the input signal, respectively.

Umn or Imn =

• Udc, Idc (simple average)

These are the average values over one period of the voltage and current signal. This function is useful when determining the average value of a DC input signal or a DC component that is superimposed on an AC input signal.

Udc or Idc =

f(t) dt

• Uac, Iac (AC component)

These are the AC components of the voltage and current. They are the square root values of the difference of the square of the true rms values of the input signal and the square of the DC component.

f(t)2 dt

•

f(t) dt

Uac =

Urms

– Udc

or Iac =

Irms

– Idc

Element

Element refers to a set of input terminals that can input a single phase of voltage and current to be measured. The WT1600 can contain up to six elements, which are numbered from 1 to 6. The element number is appended to the symbols that were defined in the earlier section, “Measurement functions on each input element” so that the correspondence between the numerical data and the element can be seen. For example, “Urms1” represents the true rms value of the voltage of element 1.

Wiring System

The selectable patterns of wiring systems vary depending on the number of input elements that are installed in the instrument. You may be able to select only a single type of wiring system or two or three types of wiring systems. When two or more types of wiring systems are selected, “A”, “B”, or “C” is appended to the symbols that were defined in the earlier section “Measurement functions of the average or sum of input elements (Σ functions)” so that the correspondence between the numerical data and the wiring unit can be seen. For example, “UrmsΣA” represents the true rms value of the average of the voltage of the input elements that are assigned to wiring unit ΣA

Efficiency

η (efficiency 1) is determined by the equation (PΣB)/(PΣA) × 100; 1/η (efficiency 2) is determined by the equation (PΣA)/(PΣB) × 100. You can create an equation using user-defined functions to determine efficiencies other than the above two. In addition, on models with the motor evaluation function (option), ηmA((Pm)/(PΣA) × 100) and ηmB((Pm)/(PΣB) × 100) can be determined.

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1.2 Measurement Function and Measurement Period

Types of Measurement Functions during Harmonic Measurement

The data (numerical data) of measurement functions during harmonic measurement is measured or computed from the sampled data*1 described later in “Measurement Period.”

* See the description of the sampled data in the earlier section “Types of Measurement

Functions during Normal Measurement.”

Types of Harmonic Measurement Functions

• Harmonic measurement functions on each input element

The following 28 types of harmonic measurement functions are available. For details on the determination of each measurement function data, see appendix 1.

Explanation of Functions

Measurement

Function

U( ) I( ) P( ) S( ) Q( )

λ( ) φ( ) φU( ) φI( )

Z( ) Rs( ) Xs( ) Rp( ) Xp( ) Uhdf( ) Ihdf( ) Phdf( ) Uthd Ithd Pthd Uthf Ithf Utif Itif hvf hcf fU fI

Chars and Numbers inside ( )

Yes Yes Yes Yes

Always 0

Yes

No No

No Yes Yes Yes Yes Yes Yes Yes Yes

Yes Yes Yes Yes Yes Yes Yes

No Yes Yes Yes Yes Yes Yes Yes Yes

Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes

No No No No No No No No No No No

All

(No ( ))

Yes Yes Yes Yes Yes Yes Yes

No No No No No No No No No

No Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes

Yes: Numerical data exists No: Numerical data does

not exist

• The meaning of measurement functions with parentheses varies depending on the characters or numbers that are inside the parentheses as follows:

• dc: Indicates numerical data of the DC component.

• 1: Indicates numerical data of the fundamental signal.

• k: Indicates numerical data from 2

to Nth order harmonics. N is the upper limit of harmonic order under analysis (see section 17.6). The upper limit is determined automatically (maximum is 100) by the frequency of the PLL source.

• All: No parentheses are appended after the measurement function. Indicates numerical data related to all waveforms including the fundamental and harmonics.

• Uhdf to hcf are measurement functions that indicate characteristics specific to the harmonics. For details on the determination of the measurement functions, see appendix 1.

• The frequency of up to three signals including the signals selected for the PLL source as fU (FreqU: voltage frequency) or fI (FreqI: current frequency) can be measured.

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1.2 Measurement Function and Measurement Period

• Harmonic measurement function that indicates the phase difference (φ) of the voltage and current between the input elements

There are five harmonic measurement functions that express the phase difference (φ). Explanation is given below for the case when the number of installed input elements is 5, the wiring system pattern is three-phase, four-wire for ΣA and threephase, three-wire for ΣB. When the target of the harmonic measurement is set to wiring unit ΣA, the target elements are 1, 2, and 3. The numerical data of the harmonic measurement functions of phase difference concerning elements 1, 2, and 3 can be determined as shown below. When the target of the harmonic measurement is set to wiring unit ΣB, the target elements are 4 and 5. The numerical data of the harmonic measurement functions of phase difference concerning elements 4 and 5 (φU4-U5, φU4-I4 and φU4-I5) can be determined. The phase difference φU4-U-6 and φU4-I6 cannot be determined.

• φU1-U2

Phase difference of the fundamental voltage U2(1) of element 2 with respect to the fundamental voltage U1(1) of element 1.

• φU1-U3

Phase difference of the fundamental voltage U3(1) of element 3 with respect to the fundamental voltage U1(1) of element 1.

• φU1-I1

Phase difference of the fundamental current I1(1) of element 1 with respect to the fundamental voltage U1(1) of element 1.

• φU1-I2

Phase difference of the fundamental current I2(1) of element 2 with respect to the fundamental voltage U1(1) of element 1.

• φU1-I3

Phase difference of the fundamental current I3(1) of element 3 with respect to the fundamental voltage U1(1) of element 1.

• Harmonic measurement function of the average or of the sum of the input elements (Σ functions)

The following 6 types of harmonic measurement functions are available. For details on the determination of each measurement function, see appendix 1.

Measurement

Function

UΣ( ) IΣ( ) PΣ( ) SΣ( ) QΣ( ) λΣ( )

Chars and Numbers

inside ( )

Yes Yes Yes Yes Yes Yes

All

(No ( ))

Yes Yes Yes Yes Yes Yes

Yes: Numerical data exists

• For measurement functions with parentheses, the value “1” is entered in the

parentheses. This represents the numerical data of the fundamental signal.

• All: No parentheses are appended after the measurement function. Indicates

numerical data related to all waveforms including the fundamental and harmonics.

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1.2 Measurement Function and Measurement Period

Element

Element refers to a set of input terminals that can input a single phase of voltage and current to be measured. The WT1600 can contain up to six elements, which are numbered from 1 to 6. The element number is appended to the symbols that were defined in the earlier section, “Harmonic measurement functions on each input element” so that the correspondence between the numerical data and the element can be seen. For example, “U1(2)” represents the voltage of the 2 of element 1.

Wiring System

The selectable patterns of wiring systems vary depending on the number of input elements that are installed in the instrument. You may be able to select only a single type of wiring system or two or three types of wiring systems. When two or more types of wiring systems are selected, “A”, “B”, or “C” is appended to the symbols that were defined in the earlier section “Harmonic measurement functions of the average or sum of input elements (Σ functions)” so that the correspondence between the numerical data and the wiring unit can be seen. For example, “UΣA(1)” represents the average of the voltage of the fundamental signal of the input elements that are assigned to wiring unit ΣA.

PLL Source «For procedures, see section 7.4»

When measuring harmonics, the fundamental period (period of the fundamental signal) must be determined in order to analyze the higher orders. The PLL (phase locked loop) source is the signal that is used to determine the fundamental period. Selecting a signal with little distortion or fluctuation for the PLL source will result in a stable harmonic measurement. An ideal signal would be a rectangular wave with amplitude that is greater than or equal to 50% or 100% of the measurement range (see section 1.3) when the crest factor (see section 5.11) is set to 3 or 6, respectively. In addition, a sampling clock signal (Smp Clk) with a frequency that is 2048 times the fundamental frequency of the waveform on which to perform harmonic measurements can be input to the external clock input connector. Stable harmonic measurement is achieved by using this sampling clock to sample data from the target waveform. Stable harmonic measurement can also be achieved by applying a clock signal (Ext Clk) that has the same period as the waveform on which to perform harmonic measurements.

order harmonic

Explanation of Functions

Types of Measurement Functions of the Motor Evaluation Function (Option)

By using the motor evaluation function (option), the rotating speed, torque, and output of a motor can be determined from the DC voltage (analog signal) or pulse count signal received from a revolution sensor, which is proportional to the rotating speed of the motor, and the DC voltage (analog signal) received from a torque meter, which is proportional to the motor’s torque. In addition, the synchronous speed and slip of a motor can be determined by setting the motor’s number of poles. Furthermore, the active power and frequency that are measured by the WT1600 and the motor output can be used to compute the motor efficiency and the total efficiency.

Types of Measurement Functions

Speed (rotating speed), Torque, Pm (motor output or mechanical power), synchronous speed (Sync), Slip, motor efficiency (ηmA), and total efficiency (ηmB). For details on the determination of the measurement functions, see appendix 1.

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1.2 Measurement Function and Measurement Period

Measurement Period

During Normal Measurement

The numerical data is measured or computed using the sampled data*1 in the measurement period that is determined according to the following principle*2.

• The measurement period is set between the first point where the reference input signal (synchronization source) crosses the level zero point (center of the amplitude) on the rising slope (or falling slope)*3 within the data update interval and the last point where the synchronization source crosses the level zero point (center of the amplitude) on the rising slope (or falling slope) within the data update interval.

• The rising or falling edge is automatically selected for the one that allows the interval to be longer.

• If the number of rising slope or falling slope is zero or one within the data update interval, the measurement period is set to the entire span within the data update interval.

• You can select which input signal will be the synchronization source (synchronized to the zero crossing point of the input signal) for each element. You can select the voltage, current, or external clock that is input to the element to be the synchronization source signal.

*1 For details on the sampled data, see the description of the sampled data in the earlier

section “Types of Measurement Functions during Normal Measurement.”

*2 The measurement period for determining the numerical data of the peak voltage or peak

current is the entire span within the data update interval. Therefore, the measurement period for the measurement functions U+pk, U-pk, I+pk, I-pk, CfU, CfI, FfU, and FfI that are determined from the maximum value of the voltage and current is also the entire span within the data update interval.

*3 Slope refers to the movement of the signal from a low level to a high level (rising edge) or

from a high level to a low level (falling edge).

*4 The data update interval is the interval by which the data is sampled for determining the

measurement functions. This is equivalent to the value you can specify in “Data Update Rate” of section 1.3.

Data update interval Measurement period

Synchronization source

Input signal U1

Input signal U2

Input signal U3

Data update interval Measurement period

Data update interval

Measurement period

During Harmonic Measurement

The data length (the number of sampled data) to be used in harmonic measurement is set to 8192, 4096, or 2048 points. The selected data length is the measurement period. When the waveform is displayed, the measurement period corresponds to one screen of the waveform.

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1.3 Measurement Conditions

Number of Installed Input Elements and Wiring Systems «For procedures, see section 5.1.»

• The selectable patterns of wiring systems vary depending on the number of input elements that are installed in the instrument. You may be able to select only a single type of wiring system or two or three types of wiring systems. You can select the wiring system from the following five types. 1P2W (single-phase, two-wire), 1P3W (single-phase, three-wire), 3P3W (three-phase, three-wire), 3P4W (three-phase, four-wire), and 3V3A (three-voltage, three-current)

• The input element assignment to wiring units ΣA, ΣB, and ΣC is determined from the wiring system pattern. This allows Σ functions of voltage, current, active power, apparent power, reactive power, power factor, phase difference, and other parameters to be determined. For the relationship between the wiring system and the determination of the Σ function, see appendix 1.

• The following table shows the relationship between the number of installed elements, the selectable wiring system patterns, and the assignment of input elements to wiring units ΣA, ΣB, and ΣC.

Explanation of Functions

Installed input elements Wiring system pattern 1 Installed input elements Wiring system pattern 1 Wiring system pattern 2

Installed input elements Wiring system pattern 1 Wiring system pattern 2 Wiring system pattern 3 Wiring system pattern 4 Installed input elements Wiring system pattern 1 Wiring system pattern 2 Wiring system pattern 3 Wiring system pattern 4

Installed input elements Wiring system pattern 1 Wiring system pattern 2 Wiring system pattern 3 Wiring system pattern 4

Installed input elements Wiring system pattern 1 Wiring system pattern 2 Wiring system pattern 3 Wiring system pattern 4 Wiring system pattern 5

1P2W

1P3W or 3P3W(ΣA)

1P2W

1P3W or 3P3W(ΣA)

1P2W(ΣA)

3P4W or 3V3A(ΣA)

1P2W

1P3W or 3P3W(ΣA)

3P4W or 3V3A(ΣA)

1P2W(ΣA)

1P2W 1P3W or 3P3W(ΣA) 1P3W or 3P3W(ΣB) 1P3W or 3P3W(ΣA) 3P4W or 3V3A(ΣB)

3P4W or 3V3A(ΣA) 1P3W or 3P3W(ΣB)

1P2W 1P3W or 3P3W(ΣA) 1P3W or 3P3W(ΣB) 1P3W or 3P3W(ΣC) 1P3W or 3P3W(ΣA) 3P4W or 3V3A(ΣB) 1P2W(ΣC)

3P4W or 3V3A(ΣA) 3P4W or 3V3A(ΣA) 3P4W or 3V3A(ΣB)

1P2W

1P3W or 3P3W(ΣB)

1P2W

3P4W or 3V3A(ΣB)

1P2W

1P2W(ΣB)

1P2W

1P3W or 3P3W(ΣB)

1P2W

1P2W(ΣB)

1P2W

1P3W or 3P3W(ΣB)

1P2W

1P2W(ΣC)

1P2W

1P2W(ΣC)

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1.3 Measurement Conditions

Measurement Range «For procedures, see section 5.2.»

Set the measurement range using an rms level. When directly inputting voltage or current signals to the input element, two types of measurement ranges is available, fixed range and auto range. When waveforms are displayed, the vertical display range corresponds to 3 or 6 times the measurement range when the crest factor (see section

5.11) is set to 3 or 6, respectively. For details on waveform display, see section 1.7, “Waveform Display.”

Fixed Range

Select each range from a number of choices. The selected range does not switch even if the amplitude of the input signal changes. For voltage, the maximum and minimum selectable ranges are 1000 V and 1.5 V, respectively, when the crest factor is set to 3. When the crest factor is set to 6, the maximum and minimum selectable ranges are 500 V and 750 mV, respectively.

Auto Range

The measurement range switches automatically depending on the amplitude of the input signal. The different ranges used in the auto range are the same as those available for fixed range.

• Range increase

• When the data of measurement function Urms or Irms exceeds 110% of the current measurement range, the measurement range is increased.

• When the peak value of the input signal exceeds 330% or 660% of the current measurement range when the crest factor is set to 3 or 6, respectively, the range is increased.

• Range decrease

When the data of the measurement function Urms or Irms is less than or equal to 30% of the measurement range and Upk and Ipk is less than or equal to 300% or 600% of the next lower range when the crest factor is set to 3 or 6, respectively, the range is decreased.

Power Range

The measurement ranges (power ranges) of active power, apparent power, and reactive power are determined by the wiring system, voltage range, and current range as follows. For the actual values of the measurement range, see section 5.2, “Setting the Measurement Range during Direct Input.”

Wiring System Power Range

1P2W (single-phase, two-wire) voltage range × current range 1P3W (single-phase, three-wire) voltage range × current range × 2

3P3W (three-phase, three-wire) (when the voltage and current ranges on the 3V3A (three-voltage, three-current) corresponding elements are set to the same range)

3P4W (three-phase four-wire) voltage range × current range × 3

(when the voltage and current ranges on the corresponding elements are set to the same range)

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Scaling «For procedures, see sections 5.3 and 5.4.»

When inputting current signals via an external current sensor or inputting voltage or current signals via the external PT (potential transformer) or CT (current transformer), the transformation ratio and coefficient can be specified.

When Inputting Current Signals via an External Current Sensor

The output of current sensors, such as shunts and clamps, can be input to the current sensor connector (EXT) and be measured. Set how many mV the current sensor outputs when 1 A of current flows (transformation ratio). Then, the input signal can be made to correspond to the numerical data or waveform display data that are obtained when the current is directly applied to the input terminals.

Measurement Function Transformation Ratio Data before Conversion Conversion Result

Current I E IS(current sensor output) IS/E Active power P E P Apparent power S E S Reactive power Q E Q Max./Min. current value Ipk E IpkS(current sensor output) IpkS/E

When Inputting Voltage or Current Signals via an External PT or CT

Measurements can be made by connecting the output of the secondary side of the PT and the output of the secondary side of the CT to the same voltage and current input terminals that are used when directly inputting a signal. Set the PT ratio, CT ratio, and power coefficient (coefficient multiplied to the power determined from the voltage and current). Then, the input signal can be made to correspond to the numerical data or waveform display data that are obtained when the current is directly applied to the input terminals.

Measurement Function Data before Conversion Conversion Result

Voltage U U2(secondary output of PT) U2 × P P: PT ratio Current I I2(secondary output of CT) II2 × C C: CT ratio Active power P P Apparent power S S Reactive power Q Q Max./Min. current value Ipk Ipk2(secondary output of CT) Ipk2 × C

2 2 2

1.3 Measurement Conditions

S S

P2 × P × C × SF SF: Power coefficient S2 × P × C × SF Q2 × P × C × SF

PS/E SS/E QS/E

Explanation of Functions

Input Filter «For procedures, see section 5.5.»

There are two types of filters. This WT1600 makes measurements by synchronizing to the input signal. Therefore, the frequency of the input signal must be measured accurately.

Line Filter

The line filter is inserted into the circuit under measurement. It removes the noise from the inverter and from distorted waveforms. The cutoff frequency can be selected.

Zero Crossing Filter

This filter is inserted only into the frequency measurement circuit. Zero crossing refers to the point where the input signal crosses the center level of the amplitude. This filter is used to accurately detect the zero crossing point. The WT1600 detects the zero crossing point with a hysteresis of approximately 5% or 10% of the measurement range when the crest factor is set to 3 or 6, respectively. The zero crossing detection is used to determine the measurement period, measure the frequency, and determine the period of a PLL source.

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1.3 Measurement Conditions

Averaging «For procedures, see section 5.6.»

The averaging function is effective when reading of the numerical display is difficult due to fluctuations. This occurs when the fluctuation of the power supply or the load is large or when the input signal frequency is low.

During Normal Measurement

Two types, exponential average and moving average, are available.

• Exponential average

The numerical data can be exponentially averaged using a specified attenuation constant. Averaging is performed according to the following equation.

(Mn – D

n =

n – 1

Dn: Displayed value that has been exponentially averaged nth times. (The

displayed value D1 on the first time is M1.)

: Displayed value that has been exponentially averaged n-1th times.

n–1

Mn: Measured data on the nth time. K: Attenuation constant (select from 2, 4, 8, 16, 32, and 64)

• Moving average

The numerical data can be linearly averaged using a specified average count. Averaging is performed according to the following equation.

n – 1

)

n – (m – 1)

n =

+ • • • M

n – 2

+ M

n – 1

+ M

Dn: Displayed value obtained by linearly averaging m points of numerical data from

the n–(m–1)th to nth time

: Measured data on the n–(m–1)th time.

n–(m–1)

..............................

: Measured data on the n–2th time.

n–2

: Measured data on the n–1th time.

n–1

Mn: Measured data on the nth time. m: Average count (select from 8, 16, 32, 64, 128, and 256)

During Harmonic Measurement

When the fundamental frequency is 50/60 Hz, the attenuation constant is automatically adjusted so that a first-order low-pass filter with a time constant of 1.5 s is achieved. Exponential averaging is performed using this attenuation constant. For example, if the data length for the analysis is 8192 points and the fundamental frequency of the PLL source is between 55 Hz and 75 Hz, the attenuation constant is set to 5.625. For other frequencies, it is set to 4.6875.

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Data Update Rate «For procedures, see section 5.7.»

This is the period by which the data is sampled for determining the measurement functions.

During Normal Measurement

Select the value from 50 ms, 100 ms, 200 ms, 500 ms, 1 s, 2 s, and 5 s. The numerical data is updated once at the selected period. You can increase the data update rate to acquire relatively fast load fluctuations in the power system or decrease the rate to acquire sampled data for several periods even for relatively long signals.

During Harmonic Measurement

The data update rate is determined by the fundamental frequency of the PLL source and the number of periods of the PLL source used for the analysis.

Hold «For procedures, see section 5.8.»

The data display of each measurement function can be held. The communication output data while the display is held is the held numeric data.

Single Measurement «For procedures, see section 5.8.»

While in the held condition, the measurement is performed once at the specified data update rate and enters the held condition.

1.3 Measurement Conditions

Explanation of Functions

MAX Hold «For procedures, see section 5.9.»

Holds the maximum value of the numerical data. Holds the data of measurement functions Urms, Umn, Udc, Uac, Irms, Imn, Idc, Iac, P, S, Q, U+pk, U-pk, I+pk, and I-pk as well as the data of the Σ function of these functions while the MAX hold function is enabled.

Master/Slave Synchronized Measurement «For procedures, see section 5.10.»

With the master instrument outputting measurement start and stop signals and the slave instrument receiving those signals, synchronized measurement on two instruments is achieved.

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1.4 Numeric Display

The numerical data can be displayed. The display format differs between normal measurement and harmonic measurement. In addition, the screen can be divided into top and bottom halves so that the numerical data can be displayed simultaneously with waveforms, bar graphs, or trends (explained later).

Display Resolution

The display resolution for voltage, current, active power, apparent power, reactive power, and so on is 60000. When the range rating (rated value of the specified range) is applied, the Σ function of voltage, current, active power, apparent power, reactive power, and so on is set to the decimal point position and unit of the element with the lowest display resolution of the target elements. For the display resolution during integration, see section 6.11.

Numerical Display during Normal Measurement «For procedures, see sections 4.1 and 6.1.»

Selecting the Number of Displayed Items

You can select the number of displayed items in the range from 4 to all. When the numerical data is displayed simultaneously with waveforms, bar graphs, or trends, only half of the selected number of items is displayed. Not all the data can be displayed on one screen. Thus, you can scroll through the displayed items to view the succeeding data.

• Example in which eight items are displayed

Measurement function

• Example in which all items are displayed

Element and wiring system

Measurement function

Data

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1.4 Numeric Display

Changing the Displayed Items

By selecting a displayed item, the numerical data value that is displayed at the position can be changed.

Change the measurement function of the third item

Change the element of the third item

Scrolling the Page

Not all the data can be displayed on one screen. Thus, you can scroll the page to display the succeeding (or preceding) data.

Resetting the Numerical Display

If the number of displayed items is set to a value other than All, the display order of measurement functions can be reset to the default order (1 default set).

Explanation of Functions

Numerical Display during Harmonic Measurement «For procedures, see sections 4.1 and 7.2.»

Selecting the Number of Displayed Items

You can select four, eight or 16 for the number of displayed items. When the numerical data is displayed simultaneously with waveforms, bar graphs, or trends, only half of the selected number of items is displayed. Not all the data can be displayed on one screen. Thus, you can scroll through the displayed items to view the succeeding data.

Example in which eight items are displayed

Measurement function

Data

IM 760101-01E

1-15

+ 393 hidden pages

YOKOGAWA WT1600 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Checking the Contents of the Package

Safety Precautions

How to Use This Manual

Contents

Chapter 1 Explanation of Functions

1.1 System Configuration and Block Diagram

1.2 Measurement Function and Measurement Period

1.3 Measurement Conditions

1.4 Numeric Display