YOKOGAWA WT310, WT330, WT310HC User Manual

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User’s Manual

WT310/WT310HC/WT330 Digital Power Meter Getting Started Guide

IM WT310-02EN

1st 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://tmi.yokogawa.com/

PIM 103-03E

Thank you for purchasing the WT310, WT310HC, or WT330 Digital Power Meter (hereinafter, “WT310/ WT310HC/WT330” will refer to all of these products). The WT310/WT310HC/WT330 is a power measurement instrument that can measure parameters such as voltage, current, and power. This getting started guide primarily explains the handling precautions and basic operations of the WT310/WT310HC/WT330. To ensure correct use, please read this manual thoroughly before beginning operation. Keep this manual in a safe place for quick reference in the event that a question arises. This manual is one of three WT310/WT310HC/WT330 manuals. Please read all manuals.

Manual Title Manual No. Description

WT310/WT310HC/WT330 Digital Power Meter User’s Manual

WT310/WT310HC/WT330 Digital Power Meter Getting Started Guide

WT310/WT310HC/WT330 Digital Power Meter Communication Interface User’s Manual

IM WT310-01EN The manual explains all the WT310/WT310HC/WT330

features, except for the communication interface features, and how to use them.

IM WT310-02EN This guide. Provided as a printed manual. The manual

explains the handling precautions and basic operations of the WT310/WT310HC/WT330 and provides an overview of its features.

IM WT310-17EN This manual explains the WT310/WT310HC/WT330

communication interface features and how to use them.

PDF files of all the manuals above are included in the accompanying CD.

Notes

• The contents of this manual are subject to change without prior notice as a result of continuing improvements to the instrument’s performance and functionality. The figures given in this manual may differ from those that actually appear on your screen.

•

Every effort has been made in the preparation of this manual t

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 YOKOGA

• The TCP/IP

WA is strictly prohibited.

software of this product and the documents concerning it have been developed/created by YOKOGAWA based on the BSD Networking Software, Release 1 that has been licensed from the Regents of the University of California.

o ensure the accuracy of its

Trademarks

• Microsoft, Internet Explorer, MS-DOS, Windows, Windows NT, Windows XP, Windows Vista, and Windows 7 are either registered trademarks or trademarks of Microsoft Corporation in the United States and/or other countries.

•

Adobe and Acrobat are either registered trademarks or tradem

• In this manual, the TM and

® symbols do not accompany their respective registered trademark or

trademark names.

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

Revisions

• January 2013 1st Edition

IM WT310-02EN

arks of Adobe Systems Incorporated.

IM WT310-02EN

Checking the Contents of the Package

WT310/WT310HC WT330 (Model: WT332/WT333)

Unpack the box and check the contents before operating the instrument. If the wrong items have been delivered, if items are missing, or if there is a problem with the appearance of the items, contact your nearest YOKOGAWA dealer.

WT310/WT310HC/WT330

Check that the product that you received is what you ordered by referring to the model name and suffix code given on the name plate on the left side panel. The WT330 includes the WT332 and WT333.

Model Suffix Code Description

WT310 WT310 Digital Power Meter

One input element model

WT310HC WT310 Digital Power Meter

One input element/large current model

WT332 WT330 Digital Power Meter

Two input element model

WT333 WT330 Digital Power Meter

Power cord

Communication interface -C1 GP-IB interface (The instrument is equipped

with one of these.) Options /C7 Ethernet Communication

-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)

-H GB Standard power cord (Part No.: A1064WD)

-N NBR Standard power cord (Part No.: A1088WD)

-C2 RS-232 interface

/EX1 /EX2 /G5 Harmonic measurement /DA4 DA output (4CH); for the WT310 or WT310HC /DA12 DA output (12CH); for the WT332 or WT333

1 Make sure that the attached power cord meets the designated standards of the country and area

that you are using it in.

2 A single instrument cannot have both the /EX1 and /EX2 optio

Three input element model

Maximum rated voltage: 125 V

Maximum rated voltage: 250 V

2.5 V/5 V/10 V external input

50 mV/100 mV/200 mV/500 mV/1 V/2 V external input

ns.

No. (Instrument number)

When contacting the dealer from which you purchased the instrument, please give them the instrument number.

Standard Accessories

D/A cable

B9879SX

Current input protection cover

B8212BX

Current input protection cover

B8212FX

Rubber feet A9088ZM

One set of manuals

Safety terminal adapter set

758931

UL/CSA Standard A1006WD

VDE Standard A1009WD

BS Standard A1054WD

AS Standard A1024WD

Power cord (one cord that matches the suffix code is included)

GB Standard A1064WD

NBR Standard A1088WD

The instrument is shipped with the following accessories. Make sure that all accessories are present and undamaged.

Checking the Contents of the Package

1 Make sure that the attached power cord meets the designated standards of the country and area

that you are using it in. 2 Same number of sets as the number of installed input elements WT310: One set with one hexagonal socket wrench WT310HC: One set with one hexagonal socket wrench WT332: Two sets with one hexagonal socket wrench WT333: Three sets with one hexagonal socket wrench 3

Included with models that have D/A output and remote control (/DA4 or /DA12) 4 For the WT310/WT310HC 5 For the WT332/WT333 6 For information on the types of printed manuals and manuals on the CD that are provided, see

page i.

IM WT310-02EN

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Checking the Contents of the Package

CD-R

The CD-R contains the data listed below. To view the PDF user’s manuals, you need Adobe Reader 5.0 or later.

PDFs of the WT310/WT310HC/WT330 User’s Manuals

These manuals are in the Manuals folder.

English

• WT310/WT310HC/WT330 Digital Power Meter User’s Manual IM WT310-01EN

• WT310/WT310HC/WT330 Digital Power Meter Getting Started Guide IM WT310-02EN

• WT310/WT310HC/WT330 Digital Power Meter Communication Interface User’s Manual IM WT310-17EN

Japanese

• WT310/WT310HC/WT330 Digital Power Meter User’s Manual IM WT310-01JA

• WT310/WT310HC/WT330 Digital Power Meter Getting Started Guide IM WT310-02JA

• WT310/WT310HC/WT330 Digital Power Meter Communication Interface User’s Manual IM WT310-17JA

Installer for the WTViewerFreePlus Application Software (For the WT310/WT310HC/WT330)

• WTViewerFreePlus_Installer.exe

• WTViewerFreePlus (folder)

• YKMUSB (folder)

PDF of the Manual for the WTViewerFreePlus Application Software

These manuals are in the Manuals folder.

English

• Application Software WTViewerFreePlus for WT310/WT310HC/WT330 User’s Manual IM 760121-02E

Japanese

• Application Software WTViewerFreePlus for WT310/WT310HC/WT330 User’s Manual IM 760121-02

WARNING

Never play this CD-R on an audio CD player. Doing so may cause loss of hearing or speaker damage due to the large sounds that may be produced.

Measurement lead 758917

Alligator clip adapter set 758922

Alligator clip adapter set 758929

Fork terminal adapter set 758921

Safety terminal adapter set 758923

External sensor cable B9284LK

Safety terminal adapter set 758931

Conversion adapter 758924

Checking the Contents of the Package

Optional Accessories (Sold separately)

The following optional accessories are available for purchase separately. For information about ordering accessories, contact your nearest YOKOGAWA dealer.

Item Model/ Min. Q’ty Note

Part No.

External sensor cable B9284LK 1 For connecting to the WT310/WT310HC/WT330’s

external current sensor input connector. Length: 0.5 m.

Measurement lead 758917 1 Two leads in one set. Used with the 758922 or

758929 adapter (sold separately). Length: 0.75 m. Rated voltage: 1000 V.*

Safety terminal adapter set 758923 1 Two pieces in one set. Rated voltage 600 V.*

758931 1 Two pieces in one set. Rated voltage 1000 V.*

Alligator clip adapter set 758922 1 Two pieces in one set. For use with measurement

lead 758917. Rated voltage 300 V.*

758929 1 Two pieces in one set. For use with measurement

lead 758917. Rated voltage 1000 V.*

Fork terminal adapter set 758921 1 Two pieces in one set. For use with measurement

lead 758917. Rated voltage 1000 V.* Rated current: 25 A.

Conversion adapter 758924 1 BNC-4 mm socket adapter. Rated voltage: 500 V.*

* The actual voltage that can be used is the lowest voltage of the WT310/WT310HC/WT330 and

cable specifications.

IM WT310-02EN

Safety Precautions

This instrument is an IEC safety class I instrument (provided with a 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 assumes no liability for the customer’s failure to comply with these requirements.

The WT310/WT310HC/WT330 is a power measurement instrument that can measure parameters such as voltage, current, and power. Do not use this instrument for anything other than its intended purpose.

The following symbols are used on this instrument.

Warning: handle with care. Refer to the user’s manual or service manual. This symbol appears

on dangerous locations on the instrument which require special instructions for proper handling

or use. The same symbol appears in the corresponding place in the manual to identify those

instructions.

Electric shock, danger

Ground (earth) or functional ground terminal (do not use this terminal as a protective ground

terminal.)

Alternating current

Both direct and alternating current

ON (power)

OFF (power)

Power-on state

Power-off state

Safety Precautions

Failure to comply with the precautions below could lead to injury or death.

WARNING

Use the Instrument Only for Its Intended Purpose

The WT310/WT310HC/WT330 is a power measurement instrument that can measure parameters such as voltage, current, and power. Do not use this instrument for anything other than as a power measurement instrument.

Check the Physical Appearance

Do not use the instrument if there is a problem with its physical appearance.

Use the Correct Power Supply

Make sure that the power supply voltage matches the instrument’s rated supply voltage and that it does not exceed the maximum voltage range specified for the power cord.

Use the Correct 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. Additionally, do not use the power cord supplied with this instrument with another instrument.

Connect the Protective Grounding Terminal

Make sure to connect the protective earth to prevent electric shock before turning on the power. The power cord that comes with the instrument is a three-prong type power cord. Connect the power cord to a properly grounded three-prong outlet.

Do Not Impair the Protective Grounding

Never cut off the internal or external protective earth wire or disconnect the wiring of the protective earth terminal. Doing so may result in electric shock or damage to the instrument.

Do Not Operate with Defective Protective Grounding or Fuses

Do not operate the instrument if the protective earth or fuse might be defective. Check the grounding and the fuse before operating the instrument.

Do Not Operate in an Explosive Atmosphere

Do not operate the instrument in the presence of flammable gasses or vapors. Doing so is extremely dangerous.

Do Not Remove Covers

Only qualified YOKOGAWA personnel should remove the instrument’s covers. The inside of the instrument is dangerous because parts of it have high voltages.

Ground the Instrument before Making External Connections

Securely connect the protective grounding before connecting to the item under measurement or to an external control unit. Before touching a circuit, turn off its power and check that it has no voltage.

IM WT310-02EN

Measurement Category

This instrument is a measurement category II product. Do not use it for measurement category III or IV measurements.

Install or Use the Instrument in Appropriate Locations

•

Do not install or use the instrument outdoors or in locations subject to rain or water.

• Install the instrument so that you can immediately remove the dangerous condition occurs.

power cord if an abnormal or

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Safety Precautions

Connect Cables Correctly

Power meters can measure large voltages and currents directly. If you use a voltage transformer or a current transformer together with this power meter, you can measure even larger voltages or currents. When you are measuring a large voltage or current, the power capacity of the item under measurement becomes large. If you do not connect the cables correctly, an overvoltage or overcurrent may be generated in the circuit under measurement. This may lead to not only damage to the power meter and the item under measurement, but electric shock and fire as well. Be careful when you connect the cables, and be sure to check the following points.

Before you begin measuring (before you turn the item under measurement on), check that:

•

Cables have been connected to the power meter’s input terminals correctly.

Check that there are no voltage measurement cables that hav

current input terminals.

Check that there are no current measurement cables that have been connected to the

voltage input terminals.

If you are measuring multiphase power, check that there are no mistakes in the phase

wiring.

• Cables have been connected to the power supply and the item under measurement correctly.

Check that there are no short circuits between terminals or between connected cables.

•

The cables are connected firmly to the current input terminals.

• There are no problems with the current input terminals and the crimping terminals, such as the presence of foreign substances.

e been connected to the

During measurement (never touch the terminals and the connected cables when the item under measurement is on), check that:

There no problems with the input terminals and the crimping terminals, such as the

• presence of foreign substances.

• The input terminals are not abnormally hot.

• The cables are connected firmly to the input terminals.

The terminal connections may become loose over time. If this happens, heat may be

generated due to changes in contact resistance. If you are going to take measurements using the same setup for a long time, periodically check that the cables are firmly connected to the terminals. (Be sure to turn both the power meter and the item under measurement off before you check the connections.)

After measuring (immediately after you turn the item under measurement of After you measure a large voltage or current, power may rema

under measurement even after you turn it off. This remaining power may lead to electric shock, so do not touch the input terminals immediately after you turn the item under measurement off. varies depending on the item.

The amount of time that power remains in the item under measurement

in for some time in the item

See below for operating environment limitations.

f):

CAUTION

This is a class A instrument designed for an industrial environment. Operation of this product in a residential area may cause radio interference in which case the user will be required to correct the interference.

Waste Electrical and Electronic Equipment

Waste Electrical and Electronic Equipment (WEEE), DIRECTIVE 2002/96/EC

(This directive is valid only in the EU.)

This product complies with the WEEE Directive (2002/96/EC) marking requirement. This

marking indicates that you must not discard this electrical/electronic product in domestic

household waste.

Product Category

With reference to the equipment

as a “Monitoring and control instruments” product.

Do not dispose in domestic household waste. When disposing products in the EU, contact your

local Yokogawa Europe B. V. office.

types in the WEEE directive Annex I, this product is classified

New EU Battery Directive

New EU Battery Directive, DIRECTIVE 2006/66/EC

(This directive is valid only in the EU.)

Batteries are included in this product. This marking indicates they shall be sorted out and

collected as ordained in ANNEX II in DIRECTIVE 2006/66/EC.

Battery type: Lithium battery

You ca

nnot replace batteries by yourself. When you need to replace batteries, contact your

local Yokogawa Europe B.V.office.

IM WT310-02EN

Conventions Used in This Manual

Units

k: Denotes 1000. Example: 100 kS/s (sample rate) K: Denotes 1024. Example: 720 KB (file size)

Notes

The notes and cautions in this manual are categorized using the following symbols.

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

instrument. This symbol appears on the instrument to 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 user’s manual, the symbol is used in conjunction with the word “WARNING” or “CAUTION.”

WARNING

CAUTION

Calls attention to information that is important for the proper operation of the

Note

Calls attention to actions or conditions that could cause serious or fatal injury to

the user, and precautions that can be taken to prevent such occurrences.

Calls attention to actions or conditions that could cause light injury to the user

or cause damage to the instrument or user’s data, and precautions that can be taken to prevent such occurrences.

software.

Characters That Appear on the 7-Segment LED

Because this instrument uses a 7-segment LED display, numbers, letters, and mathematical symbols are displayed using special characters. For details, see section 1.3, “Digital Numbers and Characters.”

(Display C)

Configure the storage feature. (Display B)

Confirm the setting.

Close menu.

Conventions Used in This Manual

Symbols and Conventions Used in Procedural Explanations

The contents of the procedural explanations are indicated using the following symbols.

This mark appears on the right side of the page to indicate features and settings that can be

operated and configured using the WTViewerFreePlus application software, which comes with the instrument.

Procedure

Operations are explained using flowcharts. See the example below for an

explanation of how various operations are indicated. All procedures are written

under the assumption that you are starting operation at the beginning of the

procedure, so you may not need to carry out all the steps in a procedure when

you are changing the settings.

Example: Operations for turning the storage feature on and off

The above flow chart indicates the following operations. You can configure items that are blinking.

Press the SHIFT key so that it illuminates, and then press SETUP (UTILITY).

A menu appears in display B.

Use ▲ or ▼ to select StorE.

Pressing either key cycles through 9 menu items.

Press SET to confirm the selection of StorE.

The StorE function menu that you selected in step 2 appears in display C.

Use ▲ or ▼ to select oFF or on.

Pressing either key cycles through 3 menu items.

Press SET to confirm the selection of oFF.

The selected or set item is confirmed when you press SET. A menu appears in display B.

Press HOLD (ESC) to return the menu display to the measurement data display.

• When you are making a number positive (no sign) or negative (–) or setting a number, when the digit in the display that the input will be added to is blank, an underscore flashes at the position of the digit.

• While you are performing menu operations, to leave the menu display, press HOLD (ESC). All setting changes that you have confirmed by pressing the SET

Explanation

This section describes the setup items and the limitations regarding the

key will be reflected in the settings.

procedures. It may not give a detailed explanation of the feature. For a detailed

IM WT310-02EN

explanation of the feature, see chapter 1 in the User’s Manual, IM WT310-01EN.

Workflow

Getting Started Guide Section 2.2 Sections 2.3 and 2.4 Section 2.8 Sections 2.9 to 2.11

Installation and Circuit Wiring

Install the WT310/WT310HC/WT330. Connect the power supply, and turn the power on. Select the measurement method. Wire the circuit under measurement.

Getting Started Guide Sections 3.1 and 3.2 Section 3.3

Common Operations

Perform key operations. Initialize settings.

User’s Manual Chapter 2

Set the Measurement Conditions

Measurement conditions

User’s Manual Section 4.1 Section 4.2 Section 4.3 Section 4.4 Section 4.5 Chapter 5 Chapter 6

Display Measured/Computed Results

Voltage, current, and active power Apparent power, reactive power, and power factor Phase angle and frequency Peak value Crest factor, etc. Integrated power (watt hour) Harmonic measurement

User’s Manual Chapter 7 Section 8.4 and chapter 5 of the Getting Started Guide Communication Interface User’s Manual

Acquire Data

Store data to internal memory. Transmit data using D/A output (option).

Transmit data through the USB, GP-IB, RS-232, or Ethernet interface.

Read the precautions in sections 2.5 and 2.7 thoroughly before connecting the wires. Also, if necessary, assemble the input terminal adapter that connects to the voltage input terminal (see section 2.6) before connecting the wires.

The figure below is provided to familiarize the first-time user with the workflow of WT310/WT310HC/ WT330 operation. For a description of an item, see the relevant section or chapter. In addition to the sections and chapters that are referenced in the figure below, this manual also contains safety precautions for handling and wiring the instrument. Be sure to observe the precautions.

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App

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

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

Waste Electrical and Electronic Equipment ..................................................................................... ix

New EU Battery Directive ................................................................................................................ix

Conventions Used in This Manual ....................................................................................................x

Workflow ......................................................................................................................................... xii

Chapter 1 Component Names and Functions

1.1 Front Panel, Rear Panel, and Top Panel .......................................................................... 1-1

1.2 Displayed Items ................................................................................................................ 1-5

1.3 Digital Numbers and Characters ...................................................................................... 1-7

1.4 Keys

Auto Range, Overrange, and Error Indications During Measurement ............................ 1-12

1.5

1.6 System Configuration .....................................................................................................

Chapter 2 Making Preparations for Measurements

2.1 Handling Precautions ....................................................................................................... 2-1

2.2 Installing the Instrument ................................................................................................... 2-3

2.3 Connecting the Power Supply .......................................................................................... 2-6

2.4 Turning the Power Switch On and Off .............................................................................. 2-7

2.5 Precautions When Wiring the Circuit under Measurement .............................................. 2-9

2.6 Assembling the Adapters for the Voltage Input Terminals .............................................. 2-12

2.7 Wiring for Accurately Measuring a Single-phase Device ................................................ 2-14

2.8 Guide for Selecting the Method Used to Measure the Pow

2.9 Wiring the Circuit under Measurement for Direct Input .................................................. 2-16

2.10 Wiring the Circuit under Measurement When Using Current Sensors ........................... 2-31

2.11 Wiring the Circuit under Measurement When Using a Voltage or Current Transformer . 2-38

2.12 Connecting to a PC via USB (Installing WTViewerFreePlus) ......................................... 2-44

Chapter 3 Common Operations

3.1 Key Operation and Functions ........................................................................................... 3-1

3.2 Entering Values ................................................................................................................ 3-3

3.3 Initializing the Settings ...................................................................................................... 3-4

................................................................................................................................. 1-8

1-14

er ........................................ 2-15

Chapter 4 Operating the WT310/WT310HC/WT330

4.1 Setting the Measurement Ranges .................................................................................... 4-1

4.2 Configuring the Wiring System Settings (Only on the WT330) ........................................ 4-4

4.3 Displaying the Voltage, Current, and Active Power on the WT310/WT310HC

4.4 Displaying Voltages, Currents, and Active Powers on the WT330 ...................................

Chapter 5 External I/0 (Option)

5.1 External I/O Connector Pin Arrangement and Pinout ....................................................... 5-1

5.2 Controlling the WT310/WT310HC/WT330 Remotely ....................................................... 5-3

5.3 Producing D/A Output ....................................................................................................... 5-4

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................. 4-5

4-6

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Contents

Chapter 6 Troubleshooting, Maintenance, and Inspection

6.1 Troubleshooting ................................................................................................................ 6-1

6.2 Error Code Descriptions and Corrective Actions .............................................................. 6-2

6.3 Recommended Part Replacement ................................................................................... 6-3

6.4 Calibration and

Adjustment .............................................................................................. 6-4

Chapter 7 Specifications

7.1 Input ................................................................................................................................. 7-1

7.2 Measurement Items .......................................................................................................... 7-4

7.3 Accuracy ........................................................................................................................... 7-5

7.4

Functions .......................................................................................................................... 7-9

7.5

External Current Sensor Input (/EX1 and /EX2 options) ................................................ 7-14

7.6 D/A Output (/DA4, /DA12 Options)

Remote Control Input/Output Signal (/DA4, /DA12 Options) .......................................... 7-14

7.7

7.8 GP-IB Interface (Standard on -C1) ................................................................................. 7-15

7.9 Serial (RS-232) Interface (Standard on -C2) ..................................................................

7.10 USB PC Interface ........................................................................................................... 7-15

7.1

1 Ethernet Interface(/C7 Option) ....................................................................................... 7-15

7.12 Safety

7.13 General Specifications ................................................................................................... 7-17

7.14 External Dimensions ...................................................................................................... 7-19

Terminal Adapter .................................................................................................

................................................................................. 7-14

7-15

7-16

Appendix

Appendix 1 How to Make Accurate Measurements ..............................................................App-1

Power switch

→ section 2.4

Handle

Used to carry the

WT310/WT310HC/WT330

→ section 2.1

7-segment LED display

→ section 1.2

Function and unit indicators

→ section 1.2

Keys

→ section 1.4

Power inlet

Power connection → section 2.3

GP-IB or RS-232 connector

Used to communicate with the WT310/WT310HC/WT330 through the GP-IB or RS-232 interface → Communication Interface User’s Manual

External I/O connector

For connecting D/A output and remote control cables → chapter 5

For connecting voltage measurement cables → sections 2.8 to 2.11

Voltage input terminals

Current input terminal

For connecting current measurement cables → sections 2.8, 2.9, and 2.11

External current sensor input connector

For connecting cables from an external current sensor → section 2.10

Ethernet port

Used to connect the WT310/WT310HC/WT330 to a network → Communication Interface User’s Manual

USB port for PCs

Used to connect the WT310/WT310HC/WT330 to a PC that has a USB port → Communication Interface User’s Manual

Chapter 1 Component Names and Functions

1.1 Front Panel, Rear Panel, and Top Panel

WT310/WT310HC

Front Panel

Component Names and Functions

Rear Panel

IM WT310-02EN

1-1

1-2

IM WT310-02EN

Vent holes → section 2.2

Inlet holes → section 2.2

(There are also inlet holes on the bottom panel.)

1.1 Front Panel, Rear Panel, and Top Panel

Top Panel

Function, unit, and element indicators

→ section 1.2

Keys

→ section 1.4

Power switch

→ section 2.4

Handle

Used to carry the WT310/WT310HC/WT330 → section 2.1

7-segment LED display

→ section 1.2

Power inlet

Power connection → section 2.3

GP-IB or RS-232 connector

Used to communicate with the WT310/WT310HC/WT330 through the GP-IB or RS-232 interface → Communication Interface User’s Manual

External I/O connector

For connecting D/A output and remote control cables → chapter 5

For connecting voltage measurement cables → sections 2.8 to 2.11

Voltage input terminals

Current input terminal

For connecting current measurement cables → sections 2.8, 2.9, and 2.11

External current sensor input connector

For connecting cables from an external current sensor → section 2.10

Ethernet port

Used to connect the WT310/WT310HC/WT330 to a network → Communication Interface User’s Manual

USB port for PCs

Used to connect the WT310/WT310HC/WT330 to a PC that has a USB port → Communication Interface User’s Manual

WT330

Front Panel

1.1 Front Panel, Rear Panel, and Top Panel

Component Names and Functions

Rear Panel

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1-3

1-4

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Vent holes → section 2.2

Inlet holes → section 2.2

(There are also inlet holes on the bottom panel.)

1.1 Front Panel, Rear Panel, and Top Panel

Top Panel

1.2 Displayed Items

Auto range monitor (CHECK RANGE)

Lights when an input signal meets the conditions for auto range switching

Measurement mode indicator (MODE)

Indicates the voltage and current measurement modes

Data update indicator (UPDATE)

Blinks when measurement data is being updated.

MAX HOLD indicator (MAX HOLD)

Lights when MAX HOLD is enabled

Scaling indicator (SCALING)

Lights when scaling is enabled

Averaging indicator (AVG)

Lights when averaging is enabled

Line filter indicator (FILTER-LINE)

Lights when the line filter is enabled

Frequency filter indicator (FILTER-FREQ)

Lights when the frequency filter is enabled

Storage indicator (STORE)

When you start storage, this indicator blinks at the pace at which storage is taking place.

Remote indicator (REMOTE)

Lights when the WT310/WT310HC/WT330 is in remote mode

Harmonic measurement display indicator (HARMONICS)

Lights when the harmonic measurement display is on

Key protection indicator (KEY PROTECT)

Lights when the keys are locked

7-segment LED display

Displays the measured data for the function that you select using the function key and displays menus when you are using menus to configure the settings

Function and unit indicators

Indicates the type of function and unit that are being shown on the 7-segment LED display

WT310/WT310HC

Component Names and Functions

IM WT310-02EN

1-5

1-6

IM WT310-02EN

Auto range monitor (CHECK RANGE)

Lights when an input signal meets the conditions for auto range switching

Measurement mode indicator (MODE)

Indicates the voltage and current measurement modes

Data update indicator (UPDATE)

Blinks when measurement data is being updated.

MAX HOLD indicator (MAX HOLD)

Lights when MAX HOLD is enabled

Scaling indicator (SCALING)

Lights when scaling is enabled

Averaging indicator (AVG)

Lights when averaging is enabled

Line filter indicator (FILTER-LINE)

Lights when the line filter is enabled

Frequency filter indicator (FILTER-FREQ)

Lights when the frequency filter is enabled

Storage indicator (STORE)

When you start storage, this indicator blinks at the pace at which storage is taking place.

Remote indicator (REMOTE)

Lights when the WT310/WT310HC/WT330 is in remote mode

Harmonic measurement display indicator (HARMONICS)

Lights when the harmonic measurement display is on

Key protection indicator (KEY PROTECT)

Lights when the keys are locked

7-segment LED display

Displays the measured data for the function that you select using the function key and displays menus when you are using menus to configure the settings

Function and unit indicators

Indicates the type of function and unit that are being shown on the 7-segment LED display

Wiring method indicator

Indicates the wiring method

1.2 Displayed Items

WT330

1.3 Digital Numbers and Characters

0 1 2 3 4 5 6 7 8 9

A B C D E F G H I J

K L M N O P Q R S T

Lowercase c

Lowercase h

U V W X Y Z

+ –

× ÷

^ (exponentiation)

Because this instrument uses a 7-segment LED display, numbers, letters, and mathematical symbols are displayed using special characters in the manner shown below. Some of the characters shown below are not used by this instrument.

Component Names and Functions

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1.4 Keys

WT310/WT310HC WT330

Switching the Display

FUNCTION Key

Choose which function to display.

ELEMENT Key (Only on the WT330)

Choose which input element to display. The indicator of the selected element lights.

Measurement Range and Mode

VOLTAGE Key

Displays the voltage range setting menu. The AUTO indicator lights when the range is set to AUTO.

CURRENT Key

Displays the current range setting menu. The AUTO indicator lights when the range is set to AUTO.

SHIFT+VOLTAGE (MODE) Key

Switches the measurement mode.

Wiring System

WIRING Key (Only on the WT330)

Select the wiring system that corresponds to the wiring system you are using to connect to the voltage and current terminals on the rear panel.

Display Hold/MAX Hold

SHIFT+CURRENT (MAX HOLD) Key

Turns the MAX hold feature on and off. When the MAX hold feature is on, the MAX HOLD indicator lights.

HOLD Key

Switches from updating the display after each data update interval to stopping the series of display operations and holding the display of the numeric data. The HOLD key lights. If you press HOLD again, the data starts getting updated again, and the HOLD key light turns off.

SHIFT + HOLD Key

While the numeric data is held, press SINGLE to measure data only once at the set data update interval and then update and hold the displayed values.

General-Purpose Keys

▲ and ▼ Keys

Select features and set values.

SHIFT+▼ (►) Key

Moves the digit that is being set in a value to the right (or from the farthest right position back to the farthest left position)

1.4 Keys

Component Names and Functions

SHIFT+▲ (.) Key

Moves the decimal point to the right (or from the farthest right position back to the farthest left position)

SET Key

Confirms the specified range, feature, or value

Zero-Level Compensation

SHIFT+SET Key (CAL)

Executes zero-level compensation. When zero-level compensation is executed, the WT310/WT310HC/ WT330 creates a zero input condition in its internal circuitry and sets the zero level to the level at that point.

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1.4 Keys

Integrated Power (Watt hour)

START Key

Starts integration

STOP Key

Stops integration

SHIFT+START (INTEG SET) Key

Displays a menu for setting the integration mode, timer, and rated integration time

SHIFT+STOP Key (RESET)

Resets the integrated value and the elapsed integration time.

Communication Interface

INTERFACE Key

Displays the communication interface setting menu and connection information

Key Lock

SHIFT+INTERFACE (KEY PROTECT) Key

Turns key protection on and off. The key protection indicator lights, and the front panel keys are locked. Press this key combination again to unlock the keys.

Other Features

SETUP Key

Set the measurement synchronization source, input filter, scaling, external sensor input, averaging, computation, data update interval, etc.

SAVE/LOAD Key

Save or load setup data.

SHIFT+SETUP (UTILITY) Key

Displays a menu for displaying system information (model information, suffix code, instrument number, and firmware version), initializing settings, setting the number of displayed digits, performing self-tests, and configuring crest factor, storage, network, and D/A output settings.

SHIFT+SAVE/LOAD (HARMONICS) Key

Displays a setting menu for turning the harmonic measurement display on and off, setting the PLL source, etc.

SHIFT Key

When you press the SHIFT key once, an indicator illuminates, and you can access the features that are written in purple below each key. Pressing the key again disables the shifted state. Holding the key for at least two seconds enables SHIFT lock.

SHIFT (LOCAL) Key

Press this key to switch from remote mode (in which the REMOTE indicator is illuminated) to local mode (in which front panel key operations are valid). This key is disabled when the WT310/WT310HC/ WT330 is in local lockout mode.

1.4 Keys

Component Names and Functions

ESC Key

Pressing this key when a setup menu is showing returns the screen to the waveform data display.

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1.5 Auto Range, Overrange, and Error Indications

WT310/WT310HC WT330

During Measurement

Overrange Indication

The measured voltage and rated current values are determined to be overrange when they exceed 140% of their rated range.* When auto range is enabled, the range is automatically increased, but if a values exceeds 140% of its maximum range, it is determined to be overrange, and the following indication appears.

* On the WT310HC, the current is determined to be overrange when it exceeds 110% of the

maximum current range (40 A range).

Computation Overflow Indication

If a computed value cannot be displayed using the specified decimal place or unit, the following indication appears.

Auto Range Monitor Indications

When an input signal meets the conditions for auto range switching, an indicator lights.

Colors and Meanings of Auto Range Monitor Indicators

Color Description

Red Peak overrange Magenta Greater than 140% of the rated range (overrange) Yellow Greater than 130% of the rated range and not more than 140% (condition for raising the auto range) Cyan 30% or less of the rated range (condition for reducing the auto range)

If the range is already at the minimum measurement range, this indicator will not light even when values are 30% or less of the rated range.

1 On the WT310HC, the current is determined to be overrange when it exceeds 110% of the maximum current

range (40 A range).

2 On the WT310HC, the current is determined to be overrange when it exceeds 100% of the maximum current

range (40 A range).

Indications When the Measured Value Is Too Small

When the measured voltage or current is 0.5% or less of the rated range (1% or less when the crest factor is set to 6), the following indications appear. These indications only appear when the measurement mode is RMS or VOTLAGE MEAN.

Function Indication

Voltage, current, apparent power, or reactive power A zero appears. Power factor or phase angle

Measurement Suspension/No Data Indication (Dashes)

When the measurement range, function, or element is switched and the displayed contents change or when there is no data to display, the following dashes are displayed temporarily.

1.5 Auto Range, Overrange, and Error Indications During Measurement

Error

Displayed in cases such as when a measured value is outside of its determined range.

Component Names and Functions

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1.6 System Configuration

Power Supply

Load

Voltage

(Apply one of them.)

Current

(Apply one of them.)

Current sensor (optional)

Remote control signal (optional)

Internal memory

Numeric data storage

Recorder

Numeric data

Setup parameters

Printer

Integration start Integration stop Hold/ single

USB interface/ GP-IB interface

/ RS-232 interface*/ Ethernet interface (optional)

D/A output (option)

Measured values are transmitted as DC voltages.

WT310/WT310HC/WT330

* The WT310/WT310HC/WT330 is standard-equipped with a GP-IB or RS-232 interface (whichever

you choose).

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Chapter 2 Making Preparations for Measurements

2.1 Handling Precautions

Safety Precautions

If you are using this instrument for the first time, make sure to read “Safety Precautions” on pages vi to viii.

Do Not Remove the Case

Do not remove the case from the instrument. Some parts of the instrument use high voltages and are extremely dangerous. For internal inspection and adjustment, contact your nearest YOKOGAWA dealer.

Unplug If Abnormal Behavior Occurs

If you notice smoke or unusual odors coming from the instrument, immediately turn off the power and unplug the power cord. Also, turn off the power to any circuits under measurement that are connected to the input terminals. Then, contact your nearest YOKOGAWA dealer.

Do Not Damage the Power Cord

Nothing should be placed on top of the power cord. The power cord should also be kept away from any heat sources. When removing the plug from the power outlet, do not pull on the cord. Pull from the plug. If the power cord is damaged, purchase a replacement with the same part number as the one indicated on page iii.

Making Preparations for Measurements

General Handling Precautions

Do Not Place Objects on Top of the Instrument

Never stack the instrument or place other instruments or any objects containing water on top of it. Doing so may damage the instrument.

Keep Electrically Charged Objects Away from the Instrument

Keep electrically charged objects away from the input terminals. They may damage the internal circuitry.

Unplug during Extended Non-Use

Turn off the power to the circuit under measurement and the instrument and remove the power cord from the outlet.

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WT310/WT310HC WT330

2.1 Handling Precautions

When Carrying the Instrument

First, turn off the circuit under measurement and remove the measurement cables. Then, turn off the instrument and remove the power cord and any attached cables. When carrying the instrument, use the handle as shown in the following figure, or use both hands to hold the instrument firmly.

When Cleaning the Instrument

When cleaning the case or the operation panel, turn off the circuit under measurement and the instrument and remove the instrument’s power cord from the outlet. Then, wipe the instrument lightly with a clean dry cloth. Do not use chemicals such as benzene or thinner. Doing so may cause discoloring and deformation.

2.2 Installing the Instrument

Installation Conditions

WARNING

• Do not install the instrument outdoors or in locations subject to rain or water.

• Install the instrument so that you can immediately remove the power cord if an abnormal or dangerous condition occurs.

Install the instrument in an indoors environment that meets the following conditions.

Flat, Even Surface

Use the instrument on a stable surface that is level in all directions. If you use the instrument on an unstable or tilted surface, the accuracy of its measurements may be impeded.

Well-Ventilated Location

Inlet and vent holes are located on the top and bottom of the instrument. To prevent internal overheating, allow at least 20 mm of space around the inlet and vent holes.

When connecting measurement wires and other various cables, allow extra space for operation.

Making Preparations for Measurements

CAUTION

If you block the inlet or outlet holes on the instrument, it will become hot and may break down.

Ambient Temperature and Humidity

Ambient temperature: 5 to 40°C Ambient humidity: 20 to 80% RH (No condensation)

Do Not Install the Instrument in the Following Places

• In direct sunlight or near heat sources

• In an environment with excessive amounts of soot, steam, dust, or corrosive gas

• Near strong magnetic field sources

• Near high-voltage equipment or power lines

• In an environment that is subject to large levels of mechanical vibration

• On an unstable surface

• Outdoors or in locations subject to rain or water

Note

• For the most accurate measurements, use the instrument in the following kind of environment.

Ambient temperature: 23°C ± 5°C Ambient humidity: 30% RH to 75% RH (no condensation)

When using the instrument in a place where the ambient temperature is 5°C to 18°C or 28°C to 40°C, add the

temperature coefficient to the accuracy as specified in chapter 7.

• When installing the instrument in a place where the ambient humidity is 30% or less, take measures to

prevent static electricity such as using an anti-static mat.

• Condensation may occur if the instrument is moved to another place where the ambient temperature or

humidity is higher, or if the temperature changes rapidly. In these kinds of circumstances, wait for at least an

hour before using the instrument, to acclimate it to the surrounding temperature.

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Rotating base

Pull this out approximately 2 mm to 3 mm, and rotate the handle.

Handle stop positions (We recommend that you use positions 1, 3, 5, and 8. Do not place a heavy load on the WT310/WT310HC/WT330 when the handle is in stop position 2 or 4.)

Movable legs

2.2 Installing the Instrument

Storage Location

Do not store the instrument:

• Where the relative humidity is greater than 80% • Where the level of mechanical vibration is high

• In direct sunlight • Where there are corrosive or explosive gasses

• Where the temperature is 60°C or higher • Where an excessive amount of soot, dust, salt,

• Near a strong source of heat or moisture • Where water

We recommend that the instrument be stored in an environment where the temperature is between 5°C and 40°C and the relative humidity is between 20% RH and 80% RH.

Installation Position

Desktop

Place the instrument in a horizontal position or tilt it on its handle or movable legs. Place the instrument on a flat, level surface as shown in the figure below.

• WT310/WT310HC To use the handle as a stand to tilt the instrument, first check that the handle is fixed in place,

and then position the instrument. To rotate the handle, first pull the handle’ approximately 2 mm to 3 mm on both the left and right sides of the instrument, and then rotate it slowly to one of its stop positions.

or iron is present

, oil, or chemicals may splash onto

the instrument

s rotary axis out

• WT330

WARNING

• When adjusting the WT310/WT310HC handle, be careful not to injure your hand with the edges of the handle.

• When you put away the handle or movable legs, be careful not to get your hand caught between the handle or movable legs and the instrument.

• Handling the movable legs or handle without firmly supporting the instrument can be dangerous. Please take the following precautions.

• Only handle the movable legs or handle when the instrument is on a stable surface.

• Do not handle the movable legs or handle when the instrument is tilted.

Do not place the instrument in any position other than those shown in the above figures.

•

Rubber Feet

If the instrument is installed so that it is flat as shown in the above figure, rubber stoppers can be attached to the feet to prevent the instrument from sliding. One set of rubber stoppers (two stoppers) are included in the package.

Rotating base

To remove the handle, rotate the handle to position 8, and then pull out the rotating base of the handle by approximately 10 mm on both sides.

WT310/WT310HC WT330

Cover

Handle

2.2 Installing the Instrument

Rack Mounting

To mount the instrument on a rack, use a rack mount kit (sold separately).

• For the WT310/WT310HC

Item Model Note Rack mount kit 751533-E2 For EIA single mount Rack mount kit 751533-J2 For JIS single mount Rack mount kit 751534-E2 For EIA dual mount Rack mount kit 751534-J2 For JIS dual mount

• For the WT330

Item Model Note Rack mount kit 751533-E3 For EIA single mount Rack mount kit 751533-J3 For JIS single mount Rack mount kit 751534-E3 For EIA dual mount Rack mount kit 751534-J3 For JIS dual mount

A summary of the procedure for mounting the instrument on a rack is given below. For detailed instructions, see the manual that is included with the rack mount kit.

Remove the handle from the instrument.

• WT310/WT310HC Rotate the handle to position 8 (see the figure on the previous page), and then pull out the rotating base

of the handle by approximately 10 mm on both sides.

• WT330 Remove the handle attachment section cover, and remove the handle attachment screws.

Making Preparations for Measurements

Note

• When rack-mounting the instrument, allow at least 20 mm of space around the inlet and exhaust holes to

• Make sure to provide adequate support from the bottom of the instrument. The support should not block the

For detailed instructions for the procedures below, see the manual that is included with the rack mount kit.

Remove the feet from the bottom of the instrument.

Peel off the seals over the rack mount attachment holes on both side panels of the instrument,

and pull out the rubber rivets.

Place seals over the feet and handle attachment holes.

Attach the rack mount kit to the instrument.

Mount the instrument on a rack.

prevent internal heating.

inlet and vent holes.

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2.3 Connecting the Power Supply

WT310/WT310HC WT330

Three-prong outlet

Before Connecting the Power Supply

To prevent electric shock and damage to the instrument, follow the warnings below.

WARNING

• Make sure that the power supply voltage matches the instrument’s rated supply voltage and that it does not exceed the maximum voltage range specified for the power cord.

• Connect the power cord after checking that the power switch of the instrument is turned OFF.

• T

o prevent fire and electric shock, only use a power cord supplied by YOKOGA

• To avoid electric shock, be sure to ground the instrument. Connect the power cord to a three-prong power outlet with a protective earth terminal.

• Do not use an ungrounded extension cord. If you do, the instrument will not be grounded.

• Use an AC outlet that complies with the power cord provided a protective grounding. If such an AC outlet is unavailable and protective grounding cannot be furnished, do not use the instrument.

Connecting the Power Cord

Check that the instrument’s power switch is off.

Connect the power cord plug to the power inlet on the rear panel of the instrument.

Connect the other end of the cord to an outlet that meets the following conditions. Use a

grounded three-prong outlet.

Item Specification Rated supply voltage 100 VAC to 120 VAC, 200 VAC to 240 VAC Permitted supply voltage range 90 VAC to 132 VAC, 180 VAC to 264 VAC Rated power supply frequency 50/60 Hz Permitted supply frequency range 48 Hz to 63 Hz Maximum power consumption WT310/WT310HC: 50 VA, WT330: 70 VA

This instrument can use a 100 V or a 200 V power supply. The maximum rated voltage differs according

to the type of power cord. Before you use the instrument, check that the voltage supplied to it is less than or equal to the maximum rated voltage of the power cord provided with it (see page v for the maximum voltage rating).

WA.

nd securely connect the

2.4 Turning the Power Switch On and Off

POWER

OFF ON

WT310/WT310HC WT330

Before Turning On the Power, Check That:

• Theinstrumentisinstalledproperly.→section2.2,“InstallingtheInstrument”

• Thepowercordisconnectedproperly.→section2.3,“ConnectingthePowerSupply”

Power Switch Location

The power switch is located in the lower left of the front panel.

Turning the Power Switch On and Off

The power switch is a push button. Press the button once to turn the instrument on and press it again to turn the instrument off.

Making Preparations for Measurements

Operations Performed When the Power Is Turned On

When the power switch is turned on, a self-test starts automatically. When the self-test completes successfully, the screen that was displayed immediately before the power was turned off appears.

Note

• After turning the power off, wait at least 10 seconds before you turn it on again.

When the Power-on Operation Does Not Finish Normally

• If the instrument does not operate as described above when the power switch is turned on, turn the power

switch off, and then:

• Check that the power cord is securely connected.

• Checkthatthecorrectvoltageiscomingtothepoweroutlet.→section2.3,“ConnectingthePower

Supply”

• After checking the above, try turning on the power while holding down SET to initialize the settings (reset

them to their factory defaults). For details about initializing the settings, see section 3.3, “Initializing

Settings.”

• If the instrument still does not work properly, contact your nearest YOKOGAWA dealer for repairs.

• If an error code is displayed, see section 6.2, “Error Code Descriptions and Corrective Actions,” and take

the appropriate actions.

• It may take a few seconds for the startup message to appear.

To Make Accurate Measurements

• Allow the instrument to warm up for at least 30 minutes after turning on the power switch.

• Aftertheinstrumentwarmsup,executezero-levelcompensation.→section8.3oftheUser’s

Manual, IM WT310-01EN

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All the LEDs light.

Power on

Measurement data display

Model: WT310, WT310HC, WT332, or WT333

Firmware version

2.4 Turning the Power Switch On and Off

Operations Performed When the Power Is Turned Off

After the power is turned off, the instrument stores the setup parameters in its memory before shutting down. The same is true when the power cord is disconnected from the outlet. The next time the power is turned on, the instrument powers up using the stored setup parameters.

Note

The instrument stores the settings using an internal lithium battery. When the lithium battery voltage falls

below a specified value, you will no longer be able to store setup parameters, and error code 901 will

appear on the screen when you turn on the power (see section 6.2, “Error Code Descriptions and Corrective

Actions”). If this message appears frequently, you need to replace the battery soon. Do not try to replace the

battery yourself. Contact your nearest YOKOGAWA dealer to have the battery replaced.

Power-on Messages

2.5 Precautions When Wiring the Circuit under Measurement

To prevent electric shock and damage to the instrument, follow the warnings below.

WARNING

• Ground the instrument before connecting measurement cables. The power cord that comes with the instrument is a three-prong cord. Insert the power cord into a grounded threeprong outlet.

•

Turn the circuit under measurement off before connecting and disconnecting cables to it.

Connecting or removing measurement cables while the power is on is dangerous.

Do not wire a current circuit to the voltage input terminal or a voltage circuit to the current

• input terminal.

• Strip the insulation covers of measurement cables so that when they are wired to the input terminals, the conductive parts (bare wires) do not protrude from the terminals. sure to fasten the input terminal screws securely so that cables do not come loose.

• When connecting measurement cables to the voltage input ter measurement cables that have safety terminals that cover their conductive parts. Using a terminal with bare conductive parts (such as a banana plug) can be dangerous if the terminal comes loose.

• When connecting cables to the external current sensor input terminals, only connect cables that have safety terminals that cover their conductive parts. Using a connector with bare conductive parts can be dangerous if the terminal comes loose.

• When you apply current directly to the current input terminals to measure it, the voltage of the item under measurement appears at the external sensor input connector electric shock, remove the cable connected to the external sensor.

• When the voltage of the circuit under measurement is being applied to the current input terminals, do not touch the external current sensor input terminals. Doing so is dangerous because the terminals are electrically connected inside the instrument.

• When connecting a measurement cable from an external current sensor to an external current sensor input connector, remove the cables connected to the current input terminals. Also, when the voltage of the circuit under measurement is being applied to the external current sensor input terminals, do not touch the current input terminals. Doing so is dangerous because the terminals are electrically connected inside the instrument.

•

When using an external voltage transformer (VT) or current transformer (CT), make sure

that it has enough dielectric strength for the voltage (U) being measured (2U + 1000 V recommended). Also, make sure that the secondary side of the CT does not become an open circuit while the power is being applied. If this happens, high voltage will appear at the secondary side of the CT

•

When using an external current sensor, make sure to use a sensor that comes in a case.

The conductive parts and case should be insulated, and the sensor should have enough dielectric strength for the voltage of the circuit under measurement. Using a bare sensor is dangerous, because there is a high probability that you might accidentally touch it.

• When using a shunt-type current sensor as an external current sensor, turn off the circuit under measurement before you connect the sensor while the power is on is dangerous.

• When using a clamp-type current sensor as an external current sensor, make sure that you understand the voltage of the circuit under measurement and the specifications and handling of the clamp-type sensor, and then confirm that there are no dangers, such as shock hazards.

• For safety reasons, when using the instrument after mounting it on a rack, furnish a switch for turning off the circuit under measurement from the front side of the rack.

• For safety reasons, after you connect the measurement cable attach the current input protection cover (screw tightening torque: 0.6 N•m). Make sure that the conductive parts do not protrude from the protection cover.

, making it extremely dangerous.

. Connecting or removing the sensor

minals, only connect

s, use the included screws to

Also, make

. To prevent

Making Preparations for Measurements

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2.5 Precautions When Wiring the Circuit under Measurement

• To make the protective features effective, before applying the voltage or current from the circuit under measurement, check that:

• The power cord provided with the instrument is being used to connect to the power

supply and that the instrument is grounded.

• The instrument is turned on.

•

The current input protection cover provided with the instrument is attached.

• When the instrument is turned on, do not apply a signal that e to the voltage or current input terminals. When the instrument is turned off, turn the circuit under measurement off. For information about other input terminals, see the specifications in chapter 6.

Instantaneous maximum allowable input (within 20 ms)

Voltage input

Peak value of 2.8 kV or rms value of 2 kV, whichever is less.

Current input

Direct input

•

WT310 and WT330 When the crest factor is 3: 0.5 A to 20 A When the crest factor is 6: 0.25 A to 10 A Peak value of 450 A or rms value of 300 A, whichever is less.

• WT310 When the crest factor is 3: 5 mA to 200 mA When the crest factor is 6: 2.5 mA to 100 mA Peak value of 150 A or rms value of 100 A, whichever is less.

• WT310HC When the crest factor is 3: 1 A to 40 A When the crest factor is 6: 0.5 A to 20 A Peak value of 450 A or rms value of 300 A, whichever is less.

External sensor input

Peak value less than or equal to 10 times the range.

xceeds the following values

Instantaneous maximum allowable input (1 s or less)

Voltage input

Peak value of 2 kV or rms value of 1.5 kV, whichever is less.

Current input

Direct input

WT310 and WT330

• When the crest factor is 3: 0.5 A to 20 A When the crest factor is 6: 0.25 A to 10 A Peak value of 150 A or rms value of 40 A, whichever is less.

• WT310 When the crest factor is 3: 5 mA to 200 mA When the crest factor is 6: 2.5 mA to 100 mA Peak value of 30 A or rms value of 20 A, whichever is less.

• WT310HC When the crest factor is 3: 1 A to 40 A When the crest factor is 6: 0.5 A to 20 A Peak value of 150 A or rms value of 44 A, whichever is less.

External sensor input

Peak value less than or equal to 10 times the range.

2.5 Precautions When Wiring the Circuit under Measurement

Continuous maximum allowable input

Voltage input

Peak value of 1.5 kV or rms value of 1.0 kV, whichever is less.

Current input

Direct input

• WT310 and WT330 When the crest factor is 3: 0.5 A to 20 A

When the crest factor is 6: 0.25 A to 10 A Peak value of 100 A or rms value of 30 A, whichever is less.

• WT310 When the crest factor is 3: 5 mA to 200 mA When the crest factor is 6: 2.5 mA to 100 mA Peak value of 30 A or rms value of 20 A, whichever is less.

• WT310HC When the crest factor is 3: 1 A to 40 A When the crest factor is 6: 0.5 A to 20 A Peak value of 100 A or rms value of 44 A, whichever is less.

External sensor input

Peak value less than or equal to 5 times the range.

CAUTION

Use measurement cables with dielectric strengths and current capacities that are appropriate for the voltage or current being measured. Example: When making measurements on a current of 20 A, use copper wires that have a conductive cross-sectional area of 4 mm Attaching a measurement cable to this product may cause radio interference in which case the user will be required to correct the interference.

or greater.

Making Preparations for Measurements

Note

• If you are measuring large currents or voltages or currents that contain high frequency components, take

special care in dealing with mutual interference and noise when you wire the cables.

• Keep measurement cables as short as possible to minimize the loss between the circuit under

measurement and the instrument.

• The thick lines on the wiring diagrams shown in sections 2.9 to 2.11 are the parts where the current flows.

Use wires that are suitable for the current levels.

• To make accurate measurements of the voltage of the circuit under measurement, connect the

measurement cable that is connected to the voltage input terminal to the circuit as closely as possible.

• To make accurate measurements, separate the measurement cables as far away from the ground wires

and the instrument’s case as possible to minimize static capacitance to the ground.

• To measure the apparent power and power factor more accurately on an unbalanced three-phase circuit,

we recommend that you use the three-voltage, three-current method (3V3A).

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2.6 Assembling the Adapters for the Voltage Input

Plug

Internal insulator

Cover

Cable

Internal insulator

Attachable cable Covering: max. diameter 3.9 mm Core wire: max. diameter 1.8 mm

10 mm

Insert the hexagonal wrench into the plug and tighten.

Plug

Hexagonal wrench

Cable tip

Cover

Terminals

When connecting a measurement cable to a WT310/WT310HC/WT330 voltage input terminal, use the included 758931 Safety Terminal Adapter or the 758923 Safety Terminal Adapter (sold separately).

758931 Safety Terminal Adapter

When using the 758931 Safety Terminal Adapter, assemble it according to the following procedure.

Assembling the Safety Terminal Adapter

Remove approximately 10 mm of the covering from the end of the cable and pass the cable

through the internal insulator.

Insert the tip of the cable into the plug. Fasten the cable in place using the hexagonal wrench.

Insert the plug into the internal insulator.

Attach the external cover. Make sure that the cover does not come off.

Note

Once you attach the cover, it is difficult to disassemble the safety terminal adapter. Use care when attaching

the cover.

Below is an illustration of the adapter after it has been assembled.

Explanation

Voltage under measurement

758921

758922

758917

758923

758931

758929

WT310/WT310HC Voltage input terminals

WT330 Voltage input terminals

96030 96031 96001 (voltage output type)

751552 (current output type)

758917 758921

758924

Current under measurement

Connecting a clamp-on probe

WT310/WT310HC

WT330

EXT input terminal

Current input terminals

EXT input terminal

96001 terminal

When you are connecting to the 96030, 96031, or 758924, remove the terminal sleeves.

Sleeves

2.6 Assembling the Adapters for the Voltage Input Terminals

Wire the adapters that come with the WT310/WT310HC/WT330 or the adapters and various sensors that are sold separately as shown below:

Wiring to a Voltage Input Terminal

Making Preparations for Measurements

Wiring to a Current Input Terminal

Use the clamp-on probes (sold separately) as shown below.

* The current input terminal and EXT input terminal cannot be wired (used) simultaneously.

IM WT310-02EN

2-13

2-14

IM WT310-02EN

2.7 Wiring for Accurately Measuring a Single-

SOURCE

LOAD

SOURCE

• Easily affected • Not easily affected

SOURCE

LOAD

SOURCE

LOAD

SOURCE

LOAD

SOURCE

• When the measured current is relatively large Connect the voltage input terminal

between the current input terminal and the load.

• When the measured current is relatively small Connect the current input terminal

between the voltage input terminal and the load.

LOAD

SOURCE

LOAD

phase Device

When you are wiring a single-phase device, there are the four patterns of terminal wiring positions shown in the following figures for wiring the voltage input and current input terminals. Depending on the terminal wiring positions, the effects of stray capacitance and the effects of the measured voltage and current amplitudes may become large. To make accurate measurements, refer to the items below when wiring the voltage input and current input terminals.

Effects of Stray Capacitance

When you are measuring the power of a single-phase device, you can minimize the effects of stray capacitance on measurement accuracy by connecting the instrument’s current input terminal to the side that is closest to the earth potential of the power supply (SOURCE).

Effects of the Measured Voltage and Current Amplitudes

Explanation

For details on the effects of stray capacitance and the effects of the measured voltage and current amplitudes, see appendix 3, “How to Make Accurate Measurements.”

2.8 Guide for Selecting the Method Used to

When the Voltage Is 600 V or Less

When the Voltage Exceeds 600 V

→ section 2.9

Voltage wiring

Direct input is not possible.

→ section 2.11

Direct input

Voltage transformer (VT)

When the Voltage Is 600 V or Less

When the Current Is 20 A or Less

When the Current Exceeds 20 A

When the Current Is 40 A or Less

When the Current Exceeds 40 A

When the Voltage Exceeds 600 V

→ section 2.9

Current wiring

Product name

Direct input is not possible.

Shunt-type current sensors cannot be used.

→ section 2.10

→ section 2.11

Direct input

WT310 or WT330

WT310HC

Shunt-type current sensor

Clamp-type current sensor (voltage output type)

Clamp-type current sensor (current output type)

Current transformer (CT)

Measure the Power

Select the measurement method from the table below according to the amplitude of the measured voltage or current. For details about a wiring method, see the section indicated in the table.

Voltage Measurement Methods

Current Measurement Methods

Making Preparations for Measurements

IM WT310-02EN

2-15

2-16

IM WT310-02EN

2.9 Wiring the Circuit under Measurement for

758931

Voltage input terminals

WT310/WT310HC

WT330

3.1

2.1

Unit: mm

Current input terminals

WT310/WT310HC

WT330

Direct Input

This section explains how to wire the measurement cable directly from the circuit under measurement to the voltage or current input terminal. To prevent electric shock and damage to the instrument, follow the warnings given in section 2.5, “Precautions When Wiring the Circuit under Measurement.”

Connecting to the Input Terminals

Voltage Input Terminals

The terminals are safety banana jacks (female) that are 4 mm in diameter. Only insert a safety terminal whose conductive parts are not exposed into a voltage input terminal. If you are using the included 758931 Safety Terminal Adapter, see section 2.6.

Current Input Terminals

The terminals are binding posts, and the screws are M6. Either wind a wire around a screw or pass a crimped terminal through the screw axis, and then tighten firmly with the terminal knob.

WARNING

• When the voltage of the circuit under measurement is being applied to the current input

terminals, do not touch the external current sensor input terminal. Doing so is dangerous because the terminals are electrically connected inside the instrument.

•

When connecting a measurement cable from an external current sensor to an external

current sensor input connector, remove the cables connected to the current input terminals. Also, when the voltage of the circuit under measurement is being applied to the external current sensor input terminals, do not touch the current input terminals. Doing so is dangerous because the terminals are electrically connected inside the instrument.

CAUTION

Confirm that no foreign materials are caught between the current input terminal and the crimped terminal. Periodically confirm that the current input terminal is not loose and that there are no foreign materials caught between the current input terminal and the crimped terminal.

Connecting to a Round Crimped Terminal

Current input terminal

Terminal base Knob

Stopper

Crimped terminal

Flathead screwdriverTweezers

Adhesive tape

Stopper shaft

Center hole

Flathead screwdriver shaft

To connect a cable with a round crimped terminal to a current input terminal, follow the procedure

below.

2.9 Wiring the Circuit under Measurement for Direct Input

Turn the current input terminal knob to loosen it. If the knob becomes difficult to turn, apply

more force to turn it further. Inside the terminal base, the stopper for the knob will disconnect from the screw portion of the knob, and the knob will become easier to turn.

The stopper for the knob will fall out of the hole in the terminal base. Be careful not to lose the stopper.

Insert the screw of the knob into the crimped terminal, and attach the knob to the terminal base.

Tighten the knob until the tip of the knob screw is slightly visible from the hole in the terminal base.

Making Preparations for Measurements

Use one of the following methods to insert the stopper into the terminal base and hold it in

place.

• Hold the stopper with tweezers and insert it into the terminal base.

• Wrap adhesive tape around a flathead screwdriver so that the

adhesive side of the tape faces

outward, then attach the stopper to the adhesive tape.

Align the shaft of the stopper with the hole in the center of the knob screw. Twist the knob until

the shaft of the stopper enters all the way into the center of the screw.

If the shaft of the stopper doesn’t enter all the way into the screw even after you tighten the knob, insert the shaft of a screwdriver into the hole in the terminal base, and twist the knob.

IM WT310-02EN

Note

When using a crimped terminal with a measurement cable, be sure to use a crimped terminal that matches

the size of the cable and to crimp the terminal to the cable using the appropriate crimping tool for the

terminal. For precautions about using crimped terminals and crimping tools, see the manuals for the crimped

terminal and the crimping tool that you are using.

2-17

2-18

IM WT310-02EN

WT310/WT310HC

Input element

The voltage input terminals and current input terminals are labeled as U and I, respectively.

Voltage input terminals

Current input

terminals

V: VOLTAGE terminal C: CURRENT terminal

SOURCE

LOAD

SOURCE

LOAD

SOURCE

LOAD

SOURCE

LOAD

SOURCE

LOAD

SOURCE

LOAD

SOURCE

LOAD

V ±

2.9 Wiring the Circuit under Measurement for Direct Input

Connecting to the WT310/WT310HC

In the wiring examples that follow, the WT310/WT310HC input elements, voltage input terminals, and current input terminals are simplified as shown in the following figure.

CAUTION

The thick lines on the wiring diagrams are the parts where the current flows. Use wires that are suitable for

the current levels.

Wiring Patterns

Power supply

DUT

Power cables

SOURCE

LOAD

SOURCE

LOAD

V ±

WT310

Low-voltage cable

High-voltage cable

2.9 Wiring the Circuit under Measurement for Direct Input

Example Wiring Procedure

This example will explain the procedure that you should use to configure the wiring when using the WT310 to measure the power of a single-phase, two-wire DUT. The procedure is the same when measuring using the WT310HC.

Making Preparations for Measurements

This example shows how to configure the wiring pattern shown in the upper left of the figure on the previous page.

Order of Connection

Generally, it is easier to follow the wiring diagram if you wire to the current input terminals first and

then to the voltage input terminals. In this example as well, we will wire to the WT310 current input

terminals first and then to the voltage input terminals.

Wiring to the Current Input Terminals

Connect the current input terminals in series with the DUT along one of the power cables between

the DUT and the power source.

Cut one power cable at the position that you want to insert the power meter into.

Cutting the low-voltage cable and inserting the power meter reduces the effects of noise during power measurement.

IM WT310-02EN

2-19

2-20

IM WT310-02EN

Current input terminals (C: CURRENT terminal)

Round crimped terminal

Power supply

DUT

SOURCE

LOAD

Voltage measurement cables

2.9 Wiring the Circuit under Measurement for Direct Input

Strip the insulation of the power cable that you cut, and attach round crimped terminals if

necessary. Connect the power cable to the WT310 in the following ways.

• Power-source-side cable: Connect to the ± current input terminal.

• DUT side cable: Connect to the CURRENT current input terminal. Pay attention to the terminal polarities so that you don’t attach the cables to terminals (C and ±) with the wrong polarities.

The wiring for current measurement is complete.

Wiring to the Voltage Input Terminals

Connect the voltage input terminals in parallel with the DUT.

Connect the voltage measurement cables to the power supply terminals of the DUT.

Use cables that meet the following conditions.

• Sufficient dielectric strength for the voltage of the circuit under measurement

• Of a size to which the 758931 Safety Terminal Adapter can be attached

• Covering: max. diameter 3.9 mm

• Core wire: max. diameter 1.8 mm

Attach 758931 Safety Terminal Adapters to the voltage measurement cables.

Safety terminal adapter

Red

Black

Voltage input terminals (V: VOLTAGE terminal)

V ±

SOURCE

LOAD

Power supply

DUT

WT310

Connect the safety terminal adapters to the WT310 voltage input terminals.

2.9 Wiring the Circuit under Measurement for Direct Input

For details on how to assemble and attach the safety terminal adapters, see section 2.5. You can avoid wiring mistakes by connecting a red adapter to the high-voltage cable and a black adapter to the low-voltage cable.

Making Preparations for Measurements

• Red adapter: Connect to the VOLTAGE voltage input terminal.

• Black adapter: Connect to the ± voltage input terminal. Pay attention to the terminal polarities so that you don’t attach the cables to terminals (V and ±) with the wrong polarities.

The wiring for voltage measurement is complete. The wiring for measuring the power of a single-

phase, two-wire DUT is complete.

IM WT310-02EN

2-21

2-22

IM WT310-02EN

Terminal block

2.9 Wiring the Circuit under Measurement for Direct Input

You can also connect to the circuit under measurement by placing a terminal block near the WT310

and connecting the power cables and voltage measurement cables to the terminal block.

VOLTAGE

CURRENT

EXT

Input element

Voltage input terminals

Current input terminals

The voltage input terminals and current input terminals of input element 1 are labeled as U1 and I1, respectively.

V: VOLTAGE terminal C: CURRENT terminal

WT330

SOURCE

LOAD

SOURCE

LOAD

Input element 1

SOURCE

LOAD

Input element 1

SOURCE

LOAD

Input element 1

SOURCE

LOAD

Input element 1

SOURCE

LOAD

SOURCE

LOAD

2.9 Wiring the Circuit under Measurement for Direct Input

Connecting to the WT330

In the wiring examples that follow, the WT330 input elements, voltage input terminals, and current input terminals are simplified as shown in the following figure.

Note

The thick lines on the wiring diagrams are the parts where the current flows. Use wires that are suitable for

the current levels.

Wiring Examples of Single-Phase, Two-Wire Systems (1P2W)

The following wiring example shows how to configure the wiring to connect to input element 1. To configure the wiring for other input elements, substitute the numbers in the figures with the appropriate element numbers.

Making Preparations for Measurements

IM WT310-02EN

2-23

2-24

IM WT310-02EN

±C

SOURCE

LOAD

Element 1

(V1, A1)

Element 3

(V3, A3)

SOURCE

LOAD

±C

SOURCE LOAD

Element 1

(V1, A1)

R S T

Element 3

(V3, A3)

SOURCE

LOAD

±C

SOURCE

Element 1

(V1, A1)

R S T N

Element 2

(V2, A2)

LOAD

Element 3

(V3, A3)

±C

2.9 Wiring the Circuit under Measurement for Direct Input

Wiring Example of a Single-Phase, Three-Wire System (1P3W)

The wiring is connected to input elements 1 and 3.

Wiring Example of a Three-Phase, Three-Wire System (3P3W)

The wiring is connected to input elements 1 and 3. Measure the line voltage using S-phase power as the reference.

Wiring Example of a Three-Phase, Four-Wire System (3P4W)

Applies to the WT333. The wiring is connected to input elements 1, 2, and 3.

SOURCE

LOAD

±C

SOURCE

Element 1

(V1, A1)

R S T

Element 2

(V2, A2)

LOAD

Element 3

(V3, A3)

±C

2.9 Wiring the Circuit under Measurement for Direct Input

Wiring Example with the Three-Voltage, Three-Current Method (3V3A)

Applies to the WT333. The wiring is connected to input elements 1, 2, and 3.

Making Preparations for Measurements

Note

For details about the relationship between the wiring system and how measured and computed values are

determined, see appendix 1, “Symbols and Determination of Measurement Functions.”

IM WT310-02EN

2-25

2-26

IM WT310-02EN

TSR

Power supply

DUT

RST

Power cables

SOURCE

LOAD

±C

SOURCE LOAD

Element 1

(V1, A1)

R S T

Element 3

(V3, A3)

TSR

RST

WT330

2.9 Wiring the Circuit under Measurement for Direct Input

Wiring Procedure Example for a Three-Phase, Three-Wire System (3P3W)

This example will explain the procedure that you should use to configure the wiring when using the WT330 to measure the power of a three-phase, three-wire DUT.

This section will explain how to configure the wiring as shown below.

Note

Order of Connection

Generally, it is easier to follow the wiring diagram if you wire to the current input terminals first and

then to the voltage input terminals. In this example as well, we will wire to the WT330 current input terminals first and then to the voltage input terminals.

Wiring to the Current Input Terminals

Connect the current input terminals between the R phase and T phase of the power cable.

The wiring procedure for a single-phase, two-wire DUT on page 2-19 is a useful reference for thinking about

the voltage of each phase and the current wiring.

Cut the power cables at the positions where you want to insert the power meter.

Strip the insulation of the power cables that you cut, and attach round crimped terminals if

TSR

Current input terminals (C: CURRENT terminal)

1 3

RST

Power supply

DUT

TSR

SOURCE

LOAD

±C

1 3

RST

2.9 Wiring the Circuit under Measurement for Direct Input

necessary. Connect the power cables to the WT330 in the following ways.

• R-phase cable: Connect to element 1.

• Power-source-side cable: Connect to the ± current input terminal of element 1.

• DUT side cable: Connect to the CURRENT current input terminal of element 1.

• T-phase cable: Connect to element 3.

• Power-source-side cable: Connect to the ± current input terminal of element 3.

• DUT side cable: Connect to the CURRENT current input terminal of element 3. Pay attention to the terminal polarities so that you don’t attach the cables to terminals (C and ±) with the wrong polarities.

Making Preparations for Measurements

The wiring for current measurement is complete.

Note

Why You Do Not Have to Connect the WT330 Current Input Terminals to the S-Phase Cable

In a three-phase, three-wire wiring system, there is no neutral line. This means that either the R, S, or T

phase is treated as a virtual neutral line when power is measured. In this example, the S-phase cable is

treated as the virtual neutral line. Therefore, in the voltage terminal connection described later, phase S is

used as the reference to measure the line voltage between phase R and phase S and between phase T and

phase S. This type of power measurement method is referred to as the two-wattmeter method.

IM WT310-02EN

2-27

2-28

IM WT310-02EN

TSR

Voltage measurement cables

1 3

RST

TSR

Safety terminal adapter

Red Black

Red

Black

1 3

RST

2.9 Wiring the Circuit under Measurement for Direct Input

Wiring to the Voltage Input Terminals

Connect the voltage input terminals in parallel with the DUT. Using phase S as the reference, measure the line voltage between phase R and phase S and

between phase T and phase S.

Connect the voltage measurement cables to the power supply terminals of the DUT. Connect

two cables to the S-phase terminal.

Use cables that meet the following conditions.

• Sufficient dielectric strength for the voltage of the circuit under measurement

• Of a size to which the 758931 Safety Terminal Adapter can be attached

• Covering: max. diameter 3.9 mm

• Core wire: max. diameter 1.8 mm

Attach 758931 Safety Terminal Adapters to the voltage measurement cables.

For details on how to assemble and attach the safety terminal adapters, see section 2.5. You can avoid wiring mistakes by connecting red adapters to the R- and T-phase cables and black adapters to the S-phase cables.

Connect the safety terminal adapters to the WT330 voltage input terminals.

TSR

Voltage input terminals (V: VOLTAGE terminal)

1 3

RST

TSR

SOURCE

LOAD

±C

1 3

RST

Power supply

DUT

WT330

2.9 Wiring the Circuit under Measurement for Direct Input

• Red R-phase adapter: Connect to the VOLTAGE voltage input terminal of element 1.

• Red T-phase adapter: Connect to the VOLTAGE voltage input terminal of element 3.

• Black S-phase adapters: Connect to the ± voltage input terminals of elements 1 and 3. Pay attention to the terminal polarities so that you don’t attach the cables to terminals (VOLTAGE and ±) with the wrong polarities.

Making Preparations for Measurements

The wiring for voltage measurement is complete. The wiring for measuring the power of a three-

phase, three-wire DUT is complete.

IM WT310-02EN

2-29

2-30

IM WT310-02EN

TSR

Terminal block

RST

TSR

Terminal block

RST

V±V±V

RSRTT

SOURCE

LOAD

±C

2.9 Wiring the Circuit under Measurement for Direct Input

You can also connect to the circuit under measurement by placing a terminal block near the WT330

and connecting the power cables and voltage measurement cables to the terminal block.

Wiring Procedure with the Three-Voltage, Three-Current Method (3V3A)

You can configure the wiring for the three-voltage, three-current method (3V3A) by adding the following wiring to the wiring for a three-phase, three-wire system.

Wiring to the Current Input Terminals

In the aforementioned steps 1 and 2, connect the current input terminals of element 2 to the

S-phase power cable.

Wiring to the Voltage Input Terminals

In the aforementioned steps 3 to 5, connect the voltage input terminals of element 2 so as to

measure the line voltage between phase R and phase T.

The result of wiring the three-phase, three-wire system shown in the figure above is for the threevoltage, three-current method (3V3A) is shown below.

2.10 Wiring the Circuit under Measurement When

Shunt-type current sensor

OUT H

OUT L

External current sensor input connector

B9284LK

WT310/WT310HC

WT330

Using Current Sensors

To prevent electric shock and damage to the instrument, follow the warnings given in section 2.5, “Precautions When Wiring the Circuit under Measurement.”

If the maximum current of the circuit under measurement exceeds the maximum range of the input elements, you can measure the current of the circuit under measurement by connecting an external current sensor to the external current sensor input connector.

•

WT310 and WT330

When the maximum current exceeds 20 Arms

• WT310HC When the maximum current exceeds 40 Arms

Current Sensor Output Type

Voltage Output

Refer to the wiring examples in this section when using a shunt-type current sensor or a clamp-type

current sensor that outputs voltage.

Current Output

If you are using a clamp-type current sensor that outputs current, see section 2.11.

Connecting to the Input Terminals

Making Preparations for Measurements

Voltage Input Terminals

External Current Sensor Input Terminal

The terminal is an isolated BNC connector. Connect an external current sensor cable with an isolated BNC connector (B9284LK, sold separately) to an external current sensor input connector.

Remove the measurement cable connected to the current input terminal. Because the external current sensor input terminal and the current input terminal are connected internally, connecting both terminals simultaneously not only results in measurement errors but may also cause damage to the instrument. Also, when the voltage of the circuit under measurement is being applied to the external current sensor input terminals, do not touch the current input terminals. Doing so is dangerous because the terminals are electrically connected inside the instrument.

IM WT310-02EN

2-31

2-32

IM WT310-02EN

Shunt-type current sensor

OUT H

OUT L

Shielded wire

B9284LK

WT310/WT310HC/WT330

Space between the connection wires

LOAD

Shunt-type current sensor

External current sensor input connector

Voltage input terminals

WT310/WT310HC/WT330

2.10 Wiring the Circuit under Measurement When Using Current Sensors

CAUTION

The thick lines on the wiring diagrams are the parts where the current flows. Use wires that are suitable for the current levels.

Note

• Make sure that you have the polarities correct when you make connections. If the polarity is reversed,

the polarity of the measurement current will be reversed, and you will not be able to make correct

measurements. Be especially careful when connecting clamp-type current sensors to the circuit under

measurement, because it is easy to reverse the connection.

• Note that the frequency and phase characteristics of the current sensor affect the measured data.

• To measure the apparent power and power factor more accurately on an unbalanced three-phase circuit,

we recommend that you use the three-voltage, three-current method (3V3A).

Notes about Using Shunt-type Current Sensors and Clamp-on Probes

Connecting an External Current Sensor Cable

To minimize error when using shunt-type current sensors, follow the guidelines below when

connecting the external current sensor cable.

• Connect the shielded wire of the external current sensor cable to the L side of the shunt output terminal (OUT).

• Minimize the area of the space between the wires connecting current sensor cable. This reduces the effects of the lines of magnetic force (which are caused by the measurement current) and the external noise that enter the space.

the current sensor to the external

Position on the (Grounded) Circuit under Measurement That You Should Connect the Shunt-type Current Sensor To

Connect the shunt-type current sensor to the power earth ground as shown in the figure below. If

you have to connect the sensor to the non-earth side, use a wire that is thicker than AWG18 (with a conductive cross-sectional area of approximately 1 mm to reduce the effects of common mode voltage. Take safety and error reduction into consideration when constructing external current sensor cables.

) between the sensor and the instrument

Clamp-type current sensor

External current sensor input connector

LOAD

Voltage input terminals

WT310/WT310HC/WT330

96001 (voltage output type)

758924

WT310/WT310HC

WT330

EXT input terminal

2.10 Wiring the Circuit under Measurement When Using Current Sensors

Ungrounded Measurement Circuits

When the circuit under measurement is not grounded and the signal is high in frequency or large

in power, the effects of the inductance of the shunt-type current sensor cable become large. In this case, use an isolation sensor (CT, DC-CT, or clamp) to perform measurements.

Making Preparations for Measurements

Connecting the 96001 Clamp-on Probe

When using the Yokogawa 96001 Clamp-on Probe, use the 758924 Conversion Adapter (optional

accessory).

IM WT310-02EN

2-33

2-34

IM WT310-02EN

WT310/WT310HC

Voltage input terminals

External current sensor input connector (EXT)

EXT

SOURCE

LOAD

Earth side

OUT L OUT H

Shunt-type current sensor

SOURCE

LOAD

Earth side

Clamp-type current sensor that outputs voltage

EXT

When You Are Using a Clamp-type Current Sensor That Outputs Voltage

When You Are Using a Shunt-Type Current Sensor

Shunt-type current sensor

B9284LK

2.10 Wiring the Circuit under Measurement When Using Current Sensors

Connecting to the WT310/WT310HC

In the wiring examples that follow, the WT310/WT310HC input elements, voltage input terminals, and current input terminals are simplified as shown in the following figure.

Wiring Example

The following figures show how to connect to the WT310/WT310HC.

When you use a shunt-type current sensor in the wiring configuration shown at the bottom of page 2-21, the configuration changes as shown in the figure below.

Connecting to the WT330

VOLTAGE

CURRENT

EXT

Input element

Voltage input terminals

Current input terminals

WT330

Shunt-type current sensor

OUT LOUT H

Input element

Clamp-type current sensor that outputs voltage

EXT

SOURCE

LOAD

Earth side

OUT L OUT H

Element 1

EXT

Shunt-type current sensor

In the wiring examples that follow, the WT330 input elements, voltage input terminals, and current input terminals are simplified as shown in the following figure.

Also, the wiring example is for when a shunt-type current sensor is connected. When connecting a clamp-type current sensor that outputs voltage, substitute the shunt-type current sensor with the clamp-type current sensor.

2.10 Wiring the Circuit under Measurement When Using Current Sensors

Making Preparations for Measurements

Wiring Example of a Single-Phase, Two-Wire System (1P2W) with a Shunt-Type Current Sensor

IM WT310-02EN

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2-36

IM WT310-02EN

SOURCE LOAD

OUT LOUT H

Element 3

Element 1

EXT EXT

SOURCE LOAD

OUT LOUT H

Element 3

Element 1

EXT EXT

SOURCE LOAD

OUT LOUT H

Element 3

Element 1

Element 2

OUT LOUT H

EXT EXT EXT

2.10 Wiring the Circuit under Measurement When Using Current Sensors

Wiring Example of a Single-Phase, Three-Wire System (1P3W) with Shunt-Type Current Sensors

The wiring is connected to input elements 1 and 3.

Wiring Example of a Three-Phase, Three-Wire System (3P3W) with Shunt-Type Current Sensors

The wiring is connected to input elements 1 and 3. Measure the line voltage using S-phase power as the reference.

Wiring Example of a Three-Phase, Four-Wire System (3P4W) with Shunt-Type Current Sensors

Model: Applies to the WT333. The wiring is connected to input elements 1, 2, and 3.

SOURCE LOAD

OUT LOUT H

Element 3

Element 1

Element 2

OUT LOUT H

EXT EXT EXT

2.10 Wiring the Circuit under Measurement When Using Current Sensors

Wiring Example with the Three-Voltage, Three-Current Method (3V3A) and Shunt-Type Current Sensors

Model: Applies to the WT333. The wiring is connected to input elements 1, 2, and 3.

Making Preparations for Measurements

Note

For details about the relationship between the wiring system and how measured and computed values are

determined, see appendix 1, “Symbols and Determination of Measurement Functions.”

IM WT310-02EN

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2-38

IM WT310-02EN

2.11 Wiring the Circuit under Measurement When Using a Voltage or Current Transformer

This section explains how to wire measurement cables from external voltage transformers1 or current transformers wiring clamp-type current sensors that output current.

*1 VT (voltage transformer) *2 CT (current transformer)

o prevent electric shock and damage to the instrument, follow the warnings given in section 2.5,

“Precautions When Wiring the Circuit under Measurement.”

to the voltage or current input terminals of input elements. Also refer to this section when

Voltage Measurement

When the maximum voltage of the circuit under measurement exceeds 600 Vrms, you can perform measurements by connecting an external VT to the voltage input terminal.

Current Measurement

If the maximum current of the circuit under measurement exceeds the maximum measurement range, you can measure the current of the circuit under measurement by connecting an external CT or a clamp-type sensor that outputs current to the current input terminal.

•

WT310 and WT330

When the maximum current exceeds 20 Arms

• WT310HC When the maximum current exceeds 40 Arms

Connecting to the Input Terminals

Voltage Input Terminals

Current Input Terminals

• The terminals are binding posts, and the screws are M6. Either wind a wire around a screw or pass

a crimped terminal through the screw axis, and then tighten firmly with the terminal knob.

• For the dimensions of the terminal parts, see section 2.9.

• When the voltage of the circuit under measurement is being applied to the current input terminals,

do not touch the external current sensor input terminals. Doing so is dangerous because the terminals are electrically connected inside the instrument.

•

When connecting a measurement cable from an external current sensor to an external current

sensor input connector, remove the cables connected to the current input terminals. Also, when the voltage of the circuit under measurement is being applied to the external current sensor input terminals, do not touch the current input terminals. Doing so is dangerous because the terminals are electrically connected inside the instrument.

•

For the precautions to follow when you connect the current inp

and after you connect these terminals, see section 2.9.

ut terminal and the crimping terminal

General VT and CT Handling Precautions

• Do not short the secondary side of a VT. Doing so may damage it.

• Do not short the secondary side of a CT. Doing so may damage it.

Also, follow the VT or CT handling precautions in the manual for the VT or CT that you are using.

758917

751552

758921

WT310/WT310HC

WT330

Current input terminals

2.11 Wiring the Circuit under Measurement When Using a Voltage or Current Transformer

CAUTION

The thick lines on the wiring diagrams are the parts where the current flows. Use wires that are suitable for the current levels.

Note

• Make sure that you have the polarities correct when you make connections. If the polarity is reversed,

the polarity of the measurement current will be reversed, and you will not be able to make correct

measurements. Be especially careful when connecting clamp-type current sensors to the circuit under

measurement, because it is easy to reverse the connection.

• Note that the frequency and phase characteristics of the VT or CT affect the measured data.

• For safety reasons, the common terminals (+/–) of the secondary side of the VT and CT are grounded in

the wiring diagrams in this section. However, the necessity of grounding and the grounding location (ground

near the VT or CT or ground near the power meter) vary depending on the item under measurement.

• To measure the apparent power and power factor more accurately on an unbalanced three-phase circuit,

we recommend that you use the three-voltage, three-current method (3V3A).

When using the Yokogawa 751552 Clamp-on Probe, use the 758917 Measurement Lead and the 758921 Fork Terminal Adapter Set (optional accessory).

Making Preparations for Measurements

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WT310/WT310HC

Input element

Voltage input terminals

Current input terminals

SOURCE LOAD

Pass-through CT

VT and pass-through CTVT and CT

SOURCE LOAD

Clamp-type current sensor that outputs current

VT and Clamp-type Current Sensor That Outputs Current

2.11 Wiring the Circuit under Measurement When Using a Voltage or Current Transformer

Connecting to the WT310/WT310HC

In the wiring examples that follow, the WT310/WT310HC input elements, voltage input terminals, and current input terminals are simplified as shown in the following figure.

Wiring Example

The following figures show how to connect to the WT310/WT310HC.

Note

Some CTs (including through types) require load resistance and power supplies. Check your CT’s manual.

VOLTAGE

CURRENT

EXT

Input element

Voltage input terminals

Current input terminals

WT330

Clamp-type current sensor that outputs current

Input element Input element

Pass-through CT

Input element

2.11 Wiring the Circuit under Measurement When Using a Voltage or Current Transformer

Connecting to the WT330

In the wiring examples that follow, the WT330 input elements, voltage input terminals, and current input terminals are simplified as shown in the following figure.

Also, the wiring examples are for when a CT is connected. When connecting a pass-through CT or a clamp-type current sensor that outputs current, substitute the CT with the pass-through CT or clamptype current sensor.

Making Preparations for Measurements

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SOURCE LOAD

Element 1

SOURCE

CT VT

LOAD

CT VT

Element 1

Element 3

SOURCE

CT VT

LOAD

CT VT

S T

Element 1 Element 3

2.11 Wiring the Circuit under Measurement When Using a Voltage or Current Transformer

Wiring Example of Single-Phase, Two-Wire Systems (1P2W) with a VT and CT

Wiring Example of a Single-Phase, Three-Wire System (1P3W) with VTs and CTs

The wiring is connected to input elements 1 and 3.

Wiring Example of a Three-Phase, Three-Wire System (3P3W) with VTs and CTs

The wiring is connected to input elements 1 and 3. Measure the line voltage using S-phase power as the reference.

SOURCE

LOAD

CT VT

S T

Element 1

Element 2 Element 3

SOURCE LOAD

S T

Element 1

Element 2 Element 3

2.11 Wiring the Circuit under Measurement When Using a Voltage or Current Transformer

Wiring Example of a Three-Phase, Four-Wire System (3P4W) with VTs and CTs

Model: Applies to the WT333. The wiring is connected to input elements 1, 2, and 3.

Making Preparations for Measurements

Wiring Example With the Three-Voltage, Three-Current Method (3V3A) and VTs and CTs

Model: Applies to the WT333. The wiring is connected to input elements 1, 2, and 3.

Note

For details about the relationship between the wiring system and how measured and computed values are

determined, see appendix 1, “Symbols and Determination of Measurement Functions.”

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2.12 Connecting to a PC via USB (Installing

WT310/WT310HC

WT330

PC monitor

Saved data

Setting changes

USB port

WT310/WT310HC

WT330

USB cable

WTViewerFreePlus)

When you connect the WT310/WT310HC/WT330 to a PC, you can save measured data to the PC and change the WT310/WT310HC/WT330 settings from the PC. In addition, you can use WTViewerFreePlus, which is a software application supplied with the WT310/WT310HC/WT330, to save measured data to the PC and change the WT310/WT310HC/WT330 settings, without having to create original communication control programs.

The WT310/WT310HC/WT330 can be connected to a PC using the following communication interfaces.

• USB

• GP-IB

• RS-232

• Ethernet

This section explains how to connect the WT310/WT310HC/WT330 to a PC via USB. PC via a different communication interface, see chapter 4 in the WTViewerFreePlus User’s Manual, IM 760121-02E.

Connecting the WT310/WT310HC/WT330 to a PC via USB

Use a USB cable to connect the USB port for PCs (type B connector) on the rear panel of the WT310/ WT310HC/WT330 to the PC.

To connect to a

2.12 Connecting to a PC via USB (Installing WTViewerFreePlus)

Installing WTViewerFreePlus

Supported operating systems: Microsoft Windows XP,1 Windows Vista,1 and Windows 7 *1 32-bit versions are supported. *2 Both 32-bit versions and 64-bit versions are supported.

Have the CD-R that contains the software ready. If an older version of WTViewerFreePlus has already been installed, uninstall it. There is a PDF of the manual for the software on the CD-R in the Manuals folder. To view the manual, you need to have Adobe Acrobat Reader 5.0 or later installed. Before you install the software, make sure that your PC meets the system requirements. The following procedure explains how to install the software on Windows 7.

Turn on the PC and start Windows. Log on as an administrator.

Insert the installation disk that contains this software into the CD drive.

On the PC, select the CD drive.

Double-click WTViewerFreePlus_Installer.exe. The InstallShield wizard will start.

Follow the instructions on the screen to install the software.

The following two items will be installed, one after the other.

• WTViewerFreePlus

• YKMUSB (USB driver)

Making Preparations for Measurements

On Windows Vista or Windows 7, the “User Account Control” window will appear during the

installation. Click Allow or Yes to continue the installation.

After the installation finishes, a new WTViewerFreePlus folder is added to the Start menu in

Windows. You can open the folder by clicking the Start button, All Programs, YOKOGAWA, and then WTViewerFreePlus.

Starting WTViewerFreePlus

Before you start WTViewerFreePlus, turn on the WT310/WT310HC/WT330.

To start WTViewerFreePlus, click the Start button, All Programs, YOKOGAWA,

WTViewerFreePlus, and then WTViewerFreePlus. After you start WTViewerFreePlus, it will automatically identify the WT310/WT310HC/WT330 devices that you can connect to and will display them in the upper left of the screen.

Note

The WT310/WT310HC/WT330 will not be automatically detected if you turn it on after starting

WTViewerFreePlus.

Select the WT310/WT310HC/WT330 that you want to connect to.

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2.12 Connecting to a PC via USB (Installing WTViewerFreePlus)

For information on how to display measured data and change the WT310/WT310HC/WT330 settings from WTViewerFreePlus, see chapters 5 and 6 in the WTViewerFreePlus User’s Manual, IM 760121-02E.

Example of a Window for Configuring the WT310/WT310HC/WT330

You can change the WT310/WT310HC/WT330 settings from a PC.

Example of a Window Showing the Measured Data of the WT310/ WT310HC/WT330

You can display multiple measured data items at the same time and save measured data to files.

2-46

IM WT310-02EN

A W VA var

TIME

Display

A W PF

A W Vpk(+) Vpk(-)

C Apk(+) Apk(-) Wpk(+)

Wpk(-)

WhWh±(+)

Ah±(-) Ah±(+) Ah Wh±(-)MATH

A W PF VHz

D AHz THD V% THD A%

3 Σ

WT332 (two input element model)

2 3

WT333 (three input element model)

Chapter 3 Common Operations

3.1 Key Operation and Functions

Key Operations

Selecting Which Function to Display

Press FUNCTION to select which function to display. Each time you press FUNCTION, the displayed function changes in the order shown below.

Common Operations

• Vpk, Apk, Wpk, Wh±, and Ah± are all displayed twice. The first time is for the positive measurements and

the second time is for the negative measurements.

• MATH and THD are displayed on the left side of the 7-segment LED display.

• Press SHIFT before pressing FUNCTION to change the displayed function in reverse order.

Selecting Which Element to Display (Only on the WT330)

Press ELEMENT to select which element to display. Each time you press ELEMENT, the input element changes in the order shown below. The WT310 and WT310HC only have one input element, so there is no input element selection.

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3-2

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3.1 Key Operation and Functions

Setup and Execution Keys

How to Use the Setup Menus That Appear When Setup Keys Are Pressed

Press a setup key to display the setup menu that corresponds to that key.

 Use▲or▼toselectanitem.

Press SET to confirm the item that you selected or set. If there are more items to set, those

items will appear. If you have finished configuring the settings and there are no more items to set, you will return to the previous menu level or to the measurement data display.

How to Display the Setup Menus That Are Written in Purple below the Keys

In the explanations in this manual, “SHIFT+key name (written in purple)” is used to indicate the

following operation.

Press SHIFT. The SHIFT key illuminates to indicate that the keys are shifted.

Now you can select the setup menus and functions written in purple below the keys.

Press the desired setup or execution key.

Using the ▲ and ▼ Keys

The operation varies as indicated below depending on what you are setting.

• When you are setting a value, you can use the keys to increase and decrease the value.

• When you are selecting a setting to configure, you can use the keys to change the selected setting.

SET Key Operation

Press SET to confirm the selected item.

ESC Key Operation

Press HOLD (ESC) while a setup menu is displayed to close the setup menu and return to the

measurement data display. All setting changes that you have confirmed by pressing the SET key will be reflected in the settings.

Execution Key Operations

Press the HOLD, START, or STOP key to execute the specified feature.

3.2 Entering Values

Moves the digit that is being set to the right

Moves the decimal point to the right

Increases the number

Reduces the number

Selecting a Value

The digit that is blinking is the one that is currently being set.

Use▲or▼toselectanumber.

Moving the Digit That Is Being Set

Press SHIFT+▼(►) to move the digit that is being set to the right. If you press SHIFT+▼(►) when the digit that is being set is the digit that is furthest to the right, the

digit that is being set will switch to the leftmost digit that can be set.

Common Operations

Moving the Decimal Point

Press SHIFT+▲(.)tomovethedecimalpointtotheright. If you press SHIFT+▲(.)when will move to the leftmost possible position.

thedecimalpointisasfartotherightasitcanbe,thedecimalpoint

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3-3

3.3 Initializing the Settings

(Display C)

End the operation, and if YES is selected, initialize the settings.

Confirm that you want to initialize the settings.

Select initialization.

(Display B)

This section explains how to reset the WT310/WT310HC/WT330 settings to their factory default values. This feature is useful when you want to cancel all of the settings that you have entered or when you want to redo measurement from scratch.

Procedure

Follow the procedure indicated by the thick lines in the following menu.

Explanation

For details on initialization, see section 8.2 in the User’s Manual, IM WT310-01E.

3-4

IM WT310-02EN

VOLT

RANGE

300

AUTO indicator for the voltage range

For information about the other digital numbers and characters that are displayed in the 7-segment LED displays, see section 1.3. An illustration of the WT310/WT310HC is used in this explanation, but this operation can be performed using the same keys on the WT330.

(Display C)1. 3.

Confirm the setting.

(Display C)1. 3.

Confirm the setting.

When the Crest Factor Is Set to 6When the Crest Factor Is Set to 3

2. 2.

Chapter 4 Operating the WT310/WT310HC/WT330

4.1 Setting the Measurement Ranges

For details, see section 2.3 in the User’s Manual, IMWT310-01EN.

To make accurate measurements, you need to set the measurement ranges (the voltage and current ranges) appropriately.

Setting the Voltage Range

Operating the WT310/WT310HC/WT330

Note

Press .

The voltage range setup menu appears. The selected voltage range blinks in display C. If you previously set the voltage range to (the AUTO indicator for the voltage range is lit), the voltage range that has been automatically selected on the basis of the measured voltage blinks.

Press or to display the voltage range that you want to select in display C.

Press .

The voltage range is confirmed, and each of the displays returns to showing measured values.

The figures below show steps 1 to 3 in flowcharts. The User’s Manual, IM WT310-01EN, uses these types of flowcharts to explain procedures.

In addition to the above operation, you can also change the voltage range without displaying the voltage

range setup menu. For details, see section 2.3 in the User’s Manual, IM WT310-01EN.

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4-2

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CURR

RANGE

AUTO indicator for the current range

(Display C)1. 3.

Confirm the setting.

(Display C)1. 3.

Confirm the setting.

When the Crest Factor Is Set to 6When the Crest Factor Is Set to 3

The unit is A.

The unit is mA.

The unit is A.

The unit is mA.

2. 2.

4.1 Setting the Measurement Ranges

Setting the Current Range

Press .

The current range setup menu appears. The selected current range blinks in display C. If you previously set the current range to (the AUTO indicator for the current range is lit), the current range that has been automatically selected on the basis of the measured current blinks.

Press or to display the current range that you want to select in display C.

Press .

The current range is confirmed, and each of the displays returns to showing measured values.

The figures below show steps 1 to 3 in flowcharts. The User’s Manual, IM WT310-01EN, uses these types of flowcharts to explain procedures.

WT310 Current Ranges

There are more ranges to choose from on models with the /EX1 or /EX2 option. For details, see section 2.4 in the User’s Manual, IM WT310-01EN.

(Display C)1. 3.

Confirm the setting.

(Display C)1. 3.

Confirm the setting.

When the Crest Factor Is Set to 6When the Crest Factor Is Set to 3

The unit is A. The unit is A.

2.2.

(Display C)1. 3.

Confirm the setting.

(Display C)1. 3.

Confirm the setting.

When the Crest Factor Is Set to 6When the Crest Factor Is Set to 3

The unit is A. The unit is A.

2. 2.

4.1 Setting the Measurement Ranges

WT310HC Current Ranges

There are more ranges to choose from on models with the /EX1 or /EX2 option. For details, see section 2.4 in the User’s Manual, IM WT310-01EN.

WT330 Current Ranges

There are more ranges to choose from on models with the /EX1 or /EX2 option. For details, see section 2.4 in the User’s Manual, IM WT310-01EN.

Note

In addition to the above operation, you can also change the current range without displaying the current

range setup menu. For details, see section 2.3 in the User’s Manual, IM WT310-01EN.

Operating the WT310/WT310HC/WT330

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4-4

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4.2 Configuring the Wiring System Settings

Wiring system indicators

(Only on the WT330)

For details, see section 2.2 in the User’s Manual, IMWT310-01EN.

On the WT330, you can set a wiring system that matches the connected circuit under measurement. The wiring system on the WT310/WT310HC is a single-phase, two-wire system.

Ifyouset

wired input elements and the total power of each of the input elements are displayed in accordance with the selected wiring system.

See appendix 1 for the formula that is used to determine the total power.

Fortheprocedure

thedisplayedfunctiontoinputelementΣ,theaveragecurrentandvoltageofeachofthe

* The current and voltage values do not have any physical meaning.

forselectinginputelementΣ,seesection4.4.

Configuring the Wiring System Settings

Press to select “3P3W” as the wiring system.

When you press , the wiring system indicators light in the following order.

4.3 Displaying the Voltage, Current, and Active

Function keys

Display A

var

TIME

Reactive power

Integration time

Apparent power

Active powerCurrentVoltage

Power on the WT310/WT310HC

For details, see section 4.1 in the User’s Manual, IMWT310-01EN.

After you select the measurement ranges (the voltage and current ranges), select the measurement items that you want to show in each display.

Displaying the Voltage in Display A on the WT310/WT310HC

Press the key for display A, and select V.

When you press , the function and unit indicators for display A light in the following order. To display the voltage on display A, press the key until V lights.

Operating the WT310/WT310HC/WT330

The WT310/WT310HC moves the decimal point so that the measured value can be displayed using the number of digits available in display A. The unit prefix changes in accordance with the position of the decimal point.

• m: 10

• k: 10

• M: 10

–3

IM WT310-02EN

4-5

4.4 Displaying Voltages, Currents, and Active

Function key Element key and indicators

Display A

var

TIME

Reactive power

Integration time

Apparent power

Active powerCurrentVoltage

Display A

1 2 3

2 3

Powers on the WT330

For details, see section 4.1 in the User’s Manual, IMWT310-01EN.

After you select the measurement ranges (the voltage and current ranges), select the measurement items that you want to show in each display.

Displaying a Voltage in Display A on the WT330

Press the key for display A, and select V.

When you press , the function and unit indicators for display A light in the following order. To display a voltage on display A, press the key until V lights.

The WT3330 moves the decimal point so that the measured value can be displayed using the number of digits available in display A. The unit prefix changes in accordance with the position of the decimal point (m: 10–3), k: 103, M: 106).

Press the keyfordisplayAtoselectinputelement1,2,3,orΣ.

When you press , the element indicators for display A light in the following order.

* On the WT332 (the two input element model) element indicator 2 is skipped.

For example, in a three-phase, three-wire system, the circuit under measurement will be connected to input elements 1 and 3 on the WT330.

• The display for input element 1 shows the line voltage between phases R-S (see page 2-28).

• The display for input element 3 shows the line voltage between phases T-S (see page 2-28).

• ThedisplayforinputelementΣshowstheaverageofthelinevoltagebetweenphasesR-SandT-S.

This value does not have any physical meaning.

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IM WT310-02EN

WT310/WT310HC

WT330

Remote control signal source

Recorder

D/A output

Remote signal

Chapter 5 External I/0 (Option)

5.1 External I/O Connector Pin Arrangement and Pinout

If you select the /DA4 or /DA12 option, D/A output and remote control features are installed in the WT310/WT310HC/WT330. You can use the external I/O connector on the rear panel to control the WT310/WT310HC/WT330 remotely and produce D/A output.

External I/0 (Option)

Remote Control

CAUTION

Only apply voltages that are within the range of 0 V to 5 V to the remote control input pins. Do not short or apply external voltages to the output pins. Doing so may damage the WT310/ WT310HC/WT330.

D/A Output

CAUTION

• Do not short or apply an external voltage to the D/A output terminal. Doing so may damage the WT310/WT310HC/WT330.

• When connecting the D/A output to another device, do not connect the wrong signal pin. Doing so may damage the WT310/WT310HC/WT330 or the connected instrument.

D/A Cable (B9879SX)

Cut the D/A cable to the necessary length, strip the insulation around the internal core wires, and connect the cable to another device.

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5-2

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131

14 26

WT rear panel

WT310/WT310HC WT330

Cable connector

2614

1 13

No Connection

No Connection No Connection No Connection

No Connection

1 2 3 4 5 6 7 8

9 10 11 12

EXT COM

EXT HOLD

EXT START EXT RESET

DA COM

No Connection

DA 3ch DA 1ch

EXT SINGLE

EXT STOP INTEG BUSY

DA COM

DA 2ch

Pin No. Signal Name Signal Name

(output) (output)

(input)

(output)

(input)

No Connection

14 15 16 17 18 19 20 21

22 23

Pin No.

DA COM

No Connection

Core Wire Color

Orange (Red 1) Orange (Red 1) Gray (Red 1) Gray (Black 1)

Orange (Black 2)

White (Red 1) White (Black 1) Yellow (Red 1) Yellow (Black 1) Pink (Red 1) Pink (Black 1) Orange (Red 2)

Gray (Red 2)

Gray (Black 2)

Orange (Black 3)

White (Red 2) White (Black 2) Yellow (Red 2) Yellow (Black 2) Pink (Red 2) Pink (Black 2) Orange (Red 3)

Gray (Red 3) Gray (Black 3) White (Red 3) White (Black 3)

Core Wire Color

No Connection

No Connection No Connection No Connection

DA 4ch

No Connection

9 10 11 12

EXT COM

EXT HOLD

EXT START EXT RESET

DA COM

No Connection DA 11ch

DA 9ch DA 7ch DA 5ch DA 3ch DA 1ch

EXT SINGLE

EXT STOP INTEG BUSY

DA COM

DA 12ch

DA 10ch DA 8ch DA 6ch DA 4ch DA 2ch

Pin No. Signal Name Signal Name

(output) (output) (output) (output) (output) (output)

(input)

(output)

(input)

No Connection

14 15 16 17 18 19 20 21

22 23

Pin No.

DA COM

No Connection

Core Wire Color

Orange (Red 1) Orange (Red 1) Gray (Red 1) Gray (Black 1)

Orange (Black 2)

White (Red 1) White (Black 1) Yellow (Red 1) Yellow (Black 1) Pink (Red 1) Pink (Black 1) Orange (Red 2)

Gray (Red 2)

Gray (Black 2)

Orange (Black 3)

White (Red 2) White (Black 2) Yellow (Red 2) Yellow (Black 2) Pink (Red 2) Pink (Black 2) Orange (Red 3)

Gray (Red 3) Gray (Black 3) White (Red 3) White (Black 3)

Core Wire Color

0.01 μF 0.01 μF

+5 V

10 kΩ

100 Ω

L level: 0 V to 1 V H level: 4 V to 5 V

Input circuit Output circuit

L level: 0 V to 1.5 V (8 mA) H level: 2.8 V to 5 V (–8 mA)

5.1 External I/O Connector Pin Arrangement and Pinout

Connector Pin Arrangement

Pinout

/DA4 (WT310/WT310HC)

/DA12 (WT330)

Note

The EXT COM and DA COM signals are connected internally.

Remote Control I/O Circuit

5.2 Controlling the WT310/WT310HC/WT330

EXT START

EXT STOP

EXT RESET

INTEG BUSY

StopStart Reset StopStart

Approx. 25

ms or more Approx. 200 ms or more

Approx. 200 ms or more

The INTEG BUSY output signal is set to low level during integration.

Use this signal when you are observing integration.

Approx. 25 ms or more

EXT HOLD

Display hold

Approx. 25 ms or more

EXT SINGLE

Display update

Data update interval or longer

Display update

Approx. 25 ms or more Approx. 25 ms or more

Remotely

Through external control, you can hold values, perform single measurements, and start, stop, and reset integration.

Controlling Integration Remotely

Apply signals according to the following timing chart.

Holding the Updating of Displayed Data

This produces the same effect as pressing HOLD. Apply an EXT HOLD signal as shown in the following figure.

Updating Held Display Data

This produces the same effect as pressing SINGLE. While the display is being held, you can update it by applying an EXT SINGLE signal.

External I/0 (Option)

Note

If the period of the EXT SINGLE signal does not meet the conditions shown in the above figure, the signal

may not be detected by the WT310/WT310HC/WT330.

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5-4

IM WT310-02EN

5.3 Producing D/A Output

Select the output format.

(Display C)

Select the D/A output feature.

(Display B)

Confirm the setting.

Close menu.

(Default setting)

(original configuration)

6, 12.

Set the output

channel.

(Display B)

Confirm the setting.

Set the output item.

(Display C)

11.

Confirm the setting.

Only on the WT330

10.

Press and to set area A (the output function).

Press to move to area B.

Press and to select an element (you cannot select an element for ).

On the WT330, select the element in the following steps 9 and 10.

13.

Confirm the setting.

Close menu.

14.

Procedure

Follow the procedure indicated by the thick lines in the following menu.

Setting the D/A Output Format

1 The number of channels varies depending on the specific option that is installed.

• /DA4 option on the WT310/WT310HC: 4 channels

• /DA12 option on the WT330: 12 channels

2 When you press SET in step 11, the output channel shown in display B changes to the next channel. For

example, ch1 changes to ch2.

3 The numbers (element numbers) that you can select vary depending on the model. For details, see

“Explanation” in this section.

Rated Integration Time

Select the rated integration time.

(Display B)

Hours

(Display B)

Press and to set the number.

Press to move the digit.

Minutes

(Display C)

Seconds

(Display D)

Confirm the setting.

Close menu.

The same as operation 4.

10.

Note

If you operate the WT310/WT310HC/WT330 frequently to configure settings such as the D/A output items and rated integration time, you can connect the WT310/WT310HC/WT330 to a PC and use WTViewerFreePlus to easily configure settings from the PC.

Explanation

D/A Output

You can output voltage, current, active power, apparent power, reactive power, power factor, phase angle, frequency, voltage peak, current peak, and integrated values using a ±5 V FS DC voltage.

5.3 Producing D/A Output

External I/0 (Option)

Number of Channels

The number of channels varies depending on the specific option that is installed.

• /DA4 option on the WT310/WT310HC: 4 channels

• /DA12 option on the WT330: 12 channels

Output Format

You can select a preconfigured output format or configure your own original format.

Using the Default Settings

Select one of the default settings to output preconfigured (default) items.

Default Values for Normal Measurement: dFLt-n

Select this setting to output normal measured values. The output settings are as follows:

Suffix Code /DA4 /DA12 Product Name WT310

WT310HC

Output Channel ch1 U1 U1 U1

ch2 I1 - U2 ch3 P1 U3 U3 ch4 fU UΣ UΣ ch5

These channels cannot be set.

2 The numbers are used to indicate input elements 1, 2, and 3.

ch6 - I2 ch7 I3 I3 ch8 IΣ IΣ ch9 P1 P1 ch10 - P2 ch11 P3 P3 ch12 PΣ PΣ

WT330 WT332 WT333

I1 I1

IM WT310-02EN

5-5

5-6

IM WT310-02EN

5.3 Producing D/A Output

Default Values for Integration: dFLt-i

Select this setting to output integrated values. The output settings are as follows:

Output Channel ch1 P1 P1 P1

These channels cannot be set.

2 The numbers are used to indicate input elements 1, 2, and 3.

Configuring an Original Output Format

You can specify output items (output functions and elements) for each output channel.

Output Functions (Area A in step 8 in the procedural explanation for setting the D/A output format)

You can select from the following options. u (voltage U), i (current I), P (active power P), VA (apparent power S),

VAr(reactivepowerQ),PF(powerfactorλ),dEG(phaseangleΦ),

uFrq (voltage frequency fU), iFrq (current frequency fI), uP (peak voltage value Upk), iP (peak current value Ipk), Ph (sum of watt hours Wp), Ph+ (positive watt hour Wp+), Ph– (negative watt hour Wp–), Ah (sum of ampere hours q), Ah+ (positive ampere hour* q+), Ah– (negative ampere hour* q-), MATH (integration), ---- (0 V D/A output; no element is specified)

Suffix Code /DA4 /DA12 Product Name WT310

WT310HC

ch2 WP1 - P2 ch3 q1 P3 P3 ch4 fU PΣ PΣ ch5 ch6 - WP2 ch7 WP3 WP3 ch8 WPΣ WPΣ ch9 q1 q1 ch10 - q2 ch11 q3 q3 ch12 qΣ qΣ

WT330 WT332 WT333

WP1 WP1

* For more information about positive and negative ampere hours, see page 5-4 of the User’s

Manual, IM WT310-01EN.

Elements (Area B in step 10 in the procedural explanation for setting the D/A output format)

Product Name Element

WT310 or WT310HC 1 WT330 WT332 1, 3, or 4

WT333 1, 2, 3, or 4

 Elementnumber4representsΣ.

5.3 Producing D/A Output

Rated Integration Time

In the D/A output of integrated values, 5.0 V FS represents the integrated value when the rated range

valueisappliedfortheratedintegrationtime.ThesameistrueifscalingisenabledorthevalueforΣ

is being measured. The default setting is 1.00.00 (1 h, 0 min, 0 s).

• Range: 0.00.00 (00 h, 00 min, 00 s) to 10000.00.00 (10000 h, 00 min, 00 s) If you set the rated integration time to 0.00.00, the D/A output value will be 0 V.

Note

• When the MAX hold feature (see section 4.6 in the User’s Manual, IM WT310-01EN) is enabled, the

maximum held values (MAX values) for the following items are displayed. The maximum held values (MAX

values) are also output in D/A output.

Voltage, current, active power, apparent power, peak voltage, peak current

• D/A output is performed for each output item with 5.0 V FS representing the application of the rated range

value for voltage, current, and power.

• Even when scaling constants are set for voltage, current, and power, the D/A output of 5.0 V FS

represents the application of the rated range value.

• Eveniftheelementshavedifferentscalingconstants,whenyousettheelementtoΣ,5.0VFSofD/A

output represents the application of the rated range value to each element.

• The D/A output for all math functions except for those indicated below is 0 V.

Efficiency, average active power during integration

External I/0 (Option)

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5-7

5-8

IM WT310-02EN

D/A output

Approx. 7.5 V

5.0 V

0.5 V

2.5 V

Displayed value

10 Hz

0.5 Hz 1 Hz

100 Hz

1 kHz

10 kHz

100 kHz

D/A output

Approx. 7.0 V

5.0 V

Integration time

When 140% of the rated input is applied.

When the rated input is applied.

D/A output

Approx. 7.5 V Approx. 7.0 V

5.0 V

–5.0V

–100

100

–140

140

Approx. –7.0 V Approx. –7.5 V

Displayed value (%)

Displayed Value

140% 100% 0% –100% –140%

Output

Approx. 7.0 V

5.0 V 0 V –5.0 V pprox. –7.0 V

5.3 Producing D/A Output

Relationship between Output Items and D/A Output Voltage

Frequency

Integrated Value

t0: Rated integration time

Other Items

• Therangebetween+5to+7Vand–5to–7VisnotoutputforλandΦ.Whenanerroroccurs,theoutput

• For the efficiency math function, +5 V represents 100%.

• For Upk and Ipk, ±5 V represents the application of 3 times the rated range value (6 times the rated range

• When the selected output function is “----” or there is no numerical data, the output is 0 V.

is approximately ±7.5 V.

value when the crest factor is 6).

5.3 Producing D/A Output

Examples of D/A Output

Voltage

When the voltage range is set to 150 V and 150 V (the rated range value) is applied, the D/A output is +5 V. When 100 V is applied, the output is 100 V/150 V × 5 V = 3.3 V.

Power

When the voltage range is set to 150 V and the current range is set to 5 A, the rated power range is 150 V × 5 A = 750 W. If the measured power value is 750 W, the D/A output is +5 V. When the measured power value is 300 W, the output is 300 W/750 W × 5V = 2.0 V.

Three-Phase Power (WT330)

When the voltage range is set to 150 V, the current range is set to 5 A, and a three-phase, three-wire

systemisconnectedtoelements1and3,theratedpowerrangeofwiringunitΣwillbeasfollows.

(Rated power range of element 1) + (rated power range of element 3) = 150 V × 5 A + 150 V × 5 A =1500 W

External I/0 (Option)

themeasured

When the measured power value is 600 W, the output is 600 W/1500 W × 5V = 2.0 V.

1 Forinformation

the second page of the appendix in the User’s Manual, IM WT310-01EN (PDF). This table shows the expressions that the WT330 uses to internally calculate the measured values. This table

alsoshowshowtothinkaboutwiringunitmeasurementranges.Inthisexample,PΣinthetable

corresponds to P1 + P3 in the three-phase, three-wire (3P3W) column.

powervalueforΣis1500W,theD/Aoutputis+5V.

aboutthepowerrangeofwiringunitΣ,seethetableofΣfunctionexpressionson

Integrated Power Values

When the voltage range is set to 150 V and the current range is set to 5 A, the rated power range is 150 V × 5 A = 750 W. In manual integration mode, when the rated integration time is set to 1 hour, the rated electrical energy value is 750 W × 1 h = 750 Wh. If you perform integration for 1 hour and the measured electrical energy is 750 W, the D/A output one hour after integration starts is + 5 V. If the measured electrical energy over 1 hour is 300 Wh, the output one hour after integration starts is 300 Wh/750 Wh × 5 V = 2.0 V. The output 30 minutes after integration starts is 150 Wh/750 Wh × 5 V = 1.0 V.

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5-9

Chapter 6 Troubleshooting, Maintenance, and Inspection

6.1 Troubleshooting

Faults and Corrective Actions

• If an error code appears on the 7-segment LED display, see section 5.2. Also, for information about communication error messages, see the appendix of the Communication Interface User’s Manual, IM WT310-17EN.

•

If servicing is necessary, or if the instrument does not operate properly even after you have

attempted to deal with the problem according to the instructions in this section, contact your nearest YOKOGAWA

Problems and Solutions Refer To

Nothing appears on the 7-segment LED display when you turn on the power.

The displayed data is not correct.

Keys do not work.

Unable to make harmonic measurements.

Unable to configure or control the instrument through the communication interface.

1 See the User’s Manual, IM WT310-01EN. 2 See the Communication Interface User’s Manual, IM WT310-17EN.

dealer.

Securely connect the power cord to the WT310/WT310HC/WT330 and to the power outlet. Set the supply voltage and frequency to within the permitted range. 2.3

Confirm that the ambient temperature and humidity are within their specified ranges. Confirm that the display is not being affected by noise. 2.1, 2.5 Check the measurement cable wiring. 2.8 to 2.11 Check the wiring system. (Applies to the WT330.) 2.8 to 2.11,

Confirm that the line filter is off. 2.9 Check the measurement period settings. 2.8 Check the FAQ at the following URL. http://tmi.yokogawa.com/ Turn the power off and then on again. 2.4

Check the REMOTE indicator. If the REMOTE indicator is illuminated, press SHIFT (LOCAL) to turn it off. Confirm that the keys are not locked. 8.5

Check the PLL source settings. 6.3 Confirm that the input signal that you have selected as the PLL source meets the specifications.

Check to make sure that the GP-IB address setting matches the specifications. ― Check to make sure that the TCP/IP settings match the specifications. ― Check to make sure that the serial (RS-232) interface parameter settings match the specifications. Confirm that the interface meets the electrical and mechanical specifications. ―

2.3

2.2

―

6.3

―

Troubleshooting, Maintenance, and Inspection

IM WT310-02EN

6-1

6-2

IM WT310-02EN

6.2 Error Code Descriptions and Corrective Actions

Information That Is Displayed When the Power Is Turned On (Display: Code.##)

Code Description Corrective Action Refer To

3 You turned on the power while holding SET, so all the

settings have been initialized.

80 The system structure has changed, so all the settings

have been initialized.

87 The WT310/WT310HC/WT330 firmware has

changed, so all the settings have been initialized.

Setting and Execution Errors (Display: Err.###)

Code Description Corrective Action Refer To

759 Network initialization failed. Check the network settings. Chapter

812 The setting or command is not available during data

storage.

813 The setting is not available when an integration

operation is being carried out or aborted. 823 Cannot be changed during CAL. Wait until CAL finishes. 8.3 832 You tried to load an empty setup parameter file. Select a file that has had setup parameters saved

840 The setting or command is not available when auto

range is on. 841 You tried to start integration after the integration time

reached the specified timer time. 842 You tried to start integration during an integration

operation. 843 The integrated value overflowed during integration or

ended abnormally because of power failure or some

other reason. 844 You tried to stop integration when no integration

operation was taking place. 845 You tried to reset integration when the mode was not

integration mode or during integration. 846 You tried to start integration despite a peak

overrange. 847 When you tried to start integration in continuous

integration mode, the integration timer time was set

to zero. 865 The setting is not available when an integration

operation is being carried out.

Reset the integration operation. 5.3

to it.

Reset the integration operation. 5.3

Set the integration timer correctly. 5.2

Abort or reset the integration operation. 5.3

3.3

―

7.2

5.3

―

System Errors (Display: Err.###)

Code Description Corrective Action Refer To

901 The setup data could not be backed up, and the

settings have been initialized.

915 This is an EEPROM SUM error. The EEPROM may be corrupted.

919 The currently installed modules and the setup data

conflict with each other. The setup data has been

initialized.

Communication Interface User’s Manual, IM WT310-17EN

2 User

’s Manual, IM WT310-01EN

The battery for backing up the setup data may have worn out. Servicing is required.

Servicing is required. Servicing is required. ―

―

6.3 Recommended Part Replacement

YOKOGAWA guarantees the WT310/WT310HC/WT330 for the period and under the conditions of the product warranty. The warranty does not cover the following expendable items. The replacement period for expendable items varies depending on the conditions of use. Refer to the table below as a general guideline. Contact your nearest YOKOGAWA dealer to have parts replaced.

Part Name Recommended Replacement Interval

Current input relay (only for the WT310)

Backup battery (lithium)

A relay for switching the current input circuit. The relay’s specifications indicated below.

• Electrical life: Approximately 50,000 operations (at the rated capacity)

• Mechanical life: Approximately 1,000,000 operations 3 years

Troubleshooting, Maintenance, and Inspection

IM WT310-02EN

6-3

6.4 Calibration and Adjustment

For calibration and adjustment, contact your nearest YOKOGAWA dealer.

6-4

IM WT310-02EN

Chapter 7 Specifications

7.1 Input

Item Specifications

Input terminal type Voltage

Plug-in terminal (safety terminal)

Current

• Direct input: Large binding post

• External current sensor input (option): isolated BNC connector

Input format Voltage

Floating input through resistive voltage divider

Current

Floating input through shunt

Measurement range V

Input impedance Voltage

oltage

Crest factor 3: 15 V, 30 V, 60 V, 150 V, 300 V, 600 V Crest factor 6: 7.5 V, 15 V, 30 V, 75 V, 150 V, 300 V

Current

•

Direct input

• Crest factor 3:

• WT310/WT332/WT333: 0.5 A, 1

• WT310 Only: 5 mA, 10 mA, 20 mA, 50 mA, 100 mA, 200 mA

• WT310HC: 1 A, 2 A, 5 A, 10 A, 20 A, 40 A

• Crest factor 6:

• WT310/WT332/WT333: 0.25 A, 0.5 A, 1 A, 2.5 A, 5 A, 10 A

• WT310 Only: 2.5 mA, 5 mA, 10 mA, 25 mA, 50 mA, 100 mA

• WT310HC: 0.5 A, 1 A, 2.5 A, 5 A, 10 A, 20 A

• External current sensor input (/EX1, /EX2)

• Crest factor 3: EX1 “2.5 V, 5 V, 10 V” or EX2 “50 mV, 100 mV, 200 mV, 500 mV, 1 V, 2 V”

• Crest factor 6: EX1 “1.25 V, 2.5 V, 5 V” or EX2 “25 mV, 50 mV, 100 mV, 250 mV, 500 mV, 1 V”

Inputresistance:Approx.

Current

• Direct input

• WT332/WT333

Crest factor 3: 0.5 A, 1 A, 2 A, 5 A, 10 A, 20 A Crest factor 6: 0.25 A, 0.5 A, 1 A, 2.5 A, 5 A, 10 A

Inputresistance:Approx.6mΩ,inputinductance:Approx.0.1μHinserieswiththe

resistance

• WT310

Crest factor 3: 0.5 A, 1 A, 2 A, 5 A, 10 A, 20 A Crest factor 6: 0.25 A, 0.5 A, 1 A, 2.5 A, 5 A, 10 A

Inputresistance:Approx.6mΩ+10mΩ(max)*Factorysetting Inputinductance:Approx.0.1μHinserieswiththeresistance

• WT310

Crest factor 3: 5 mA, 10 mA, 20 mA, 50 mA, 100 mA, 200 mA Crest factor 6: 2.5 mA, 5 mA, 10 mA, 25 mA, 50 mA, 100 mA

Inputresistance:Approx.500mΩ,inputinductance:Approx.0.1μHinserieswiththe

resistance

• WT310HC

Crest factor 3: 1 A, 2 A, 5 A, 10 A, 20 A, 40 A Crest factor 6: 0.5 A, 1 A, 2.5 A, 5 A, 10 A, 20 A

Inputresistance:Approx.5mΩ,inputinductance:Approx.0.1μHinserieswiththe

resistance

• External current sensor input (/EX1): Crest factor 3: 2.5 V, 5 V, 10 V Crest factor 6: 1.25 V, 2.5 V, 5 V

Inputresistance:Approx.100kΩ

• External current sensor input (/EX2): Crest factor 3: 50 mV, 100 mV, 200 mV, 500 mV, 1 V, 2 V Crest factor 6: 25 mV, 50 mV, 100 mV, 250 mV, 500 mV, 1 V

Inputresistance:Approx.20kΩ

2MΩ,inputcapacitance:Approx.13pFinparallelwiththeresistance

A, 2 A, 5 A, 10 A, 20 A

Specifications

IM WT310-02EN

7-1

YOKOGAWA WT310, WT330, WT310HC User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Checking the Contents of the Package

Safety Precautions

Waste Electrical and Electronic Equipment

New EU Battery Directive

Conventions Used in This Manual

Workflow

Contents

Chapter 1 Component Names and Functions

1.1 Front Panel, Rear Panel, and Top Panel

1.2 Displayed Items

1.3 Digital Numbers and Characters

1.4 Keys

1.6 System Configuration

Chapter 2 Making Preparations for Measurements

2.1 Handling Precautions

2.2 Installing the Instrument

2.3 Connecting the Power Supply

2.4 Turning the Power Switch On and Off

2.5 Precautions When Wiring the Circuit under Measurement

2.11 Wiring the Circuit under Measurement When Using a Voltage or Current Transformer

Chapter 3 Common Operations

3.1 Key Operation and Functions

3.2 Entering Values

3.3 Initializing the Settings

Chapter 4 Operating the WT310/WT310HC/WT330

4.1 Setting the Measurement Ranges

Chapter 5 External I/0 (Option)

5.1 External I/O Connector Pin Arrangement and Pinout

5.3 Producing D/A Output

Chapter 6 Troubleshooting, Maintenance, and Inspection

6.1 Troubleshooting

6.2 Error Code Descriptions and Corrective Actions

6.3 Recommended Part Replacement

6.4 Calibration and Adjustment

Chapter 7 Specifications

7.1 Input