Yokogawa CW120, CW121 Operating Manual

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User's Manual

IM CW120-E

CW120/121 CLAMP-ON POWER METERS

Before Use

Before starting measurement with your CW120 or CW121, fill in the Setting Check Sheet in the back of the site.

Operation Guide

(IM CW120P-E) with your particular settings, to facilitate setting on

4th Edition: May. 2007 (KP)

IM CW120-E

Introduction

Thank you for purchasing our CW120 or CW121 Clamp-on Power Meter. This User’s Manual explains the functions of the CW120/121, as well as the operating methods and handling precautions. Before using the CW120/121, read this manual thoroughly to ensure correct use of the instrument.

The Operation Guide manual, available separately in addition to this manual, describes the basic procedures for performing such tasks as measurement operations and settings. Use the Operation Guide together with this in-depth manual.

When you have finished reading this manual, carefully store it in a convenient place for future reference.

Notes

The contents of this manual are subject to change without prior notice. In addition, figures and illustrations representing display appearances in this manual may differ from the actual appearances. Every effort has been made to ensure the accuracy of this manual. If you notice any errors or have any questions, however, please contact one of the Yokogawa sales offices listed on the back cover of this manual or the sales representative from which you purchased the instrument. The contents of this manual may not be transcribed or reproduced, in part or in whole, without prior permission.

Trademark Acknowledgments

All company and product names appearing in this document are trademarks or registered trademarks of their respective holders.

Revision Information

December 2001: 1st Edition June 2003: 2nd Edition – – – : 3rd Edition May 2007: 4th Edition

IM CW120-E

Checking Items in the Package

After opening the package, check the product as follows before use. If the delivered product is the wrong model, any item is missing, or the appearance is defective, contact the vendor from which you purchased the product.

CW120/121 Main Unit

Check the model and suffix (specifications) codes in the MODEL and SUFFIX fields of the nameplate at the back of the instrument to ensure that the instrument is exactly as specified in your purchase order.

Model and Suffix Codes

Model CW120

CW121

Power cord

Communication interface

Option codes

Suffix Code

-D

-F

-H

-R

-S

-1

-2 /C1 /C2 /C3 /C4 /C5 /C6 /C7 /C8

Clamp-on power meter for single-phase two-wire, single-phase three-wire, three-phase three-wire, and single-phase tow-wire ×2* circuits

Clamp-on power meter for single-phase two-wire, single-phase three-wire, three-phase three-wire, three-phase four-wire, single-phase tow-wire ×2*, and single-phase tow-wire ×3* circuits

UL/CSA standard VDE standard GB standard SAA standard BS standard With RS-232-C interface With RS-485 interface Clamp-on current probe for 20/200 A (2 pieces/set) Clamp-on current probe for 20/200 A (3 pieces/set) Clamp-on current probe for 50/500 A (2 pieces/set) Clamp-on current probe for 50/500 A (3 pieces/set) Clamp-on current probe for 200/1000 A (2 pieces/set) Clamp-on current probe for 200/1000 A (3 pieces/set) Clamp-on current probe for 5/50 A (2 pieces/set) Clamp-on current probe for 5/50 A (3 pieces/set) * “×2”, “×3” means multiple-system load measurements.

Specification

No. (serial number):

Refer to this serial number on the nameplate when contacting the vendor about the instrument.

IM CW120-E

Accessories

Make sure that the package contains all the accessories listed below and that they are all free from any damage.

Product Name Part Number Qty Remarks

Power cord B9988YA

(One of the four options) B9988YB -F: VDE standard

Voltage probes

User’s Manual IM CW120-E

Operation Guide IM CW120P-E

5. Set Up Disk 2 TOOL BOX

1. 2. 3.

(for CW120) (for CW121)

B9988YJ -H: GB standard B9988YC -R: SAA standard B9988YD -S: BS standard

91018 3 91007 4 Color: Black, red, yellow, blue

1 1

Checking Items in the Package

-D: UL/CSA standard

Color: Black, red, yellow

IM CW120-E

Checking Items in the Package

Peripherals (Optional)

The products listed below are available as optional peripherals. For technical and ordering inquiries concerning the peripherals, contact the vendor from which you purchased the instrument. If you purchased any one of the optional peripherals together with the CW120/121, make sure it is free from any damage.

Product Name

Clamp-on current probe for 20/200 A 96030 1

Clamp-on current probe for 50/500 A 96031 1

Clamp-on current probe for 200/1000

Clamp-on current probe for 5/50 A 96033 1

Power supply cabl Voltage probes (for CW121

Voltage probes (for CW120 RS-232C cabl

RS-232 serial printer cabl Printe

AC adapter (for printer) 94006 1 Power supply 200-240 V AC AC adapter (for printer) 94007 1 Power supply 100-120 V AC Thermal printer pape Carrying case 93022 1 For CW120 Series Meter case 93023 1 For CW120 Series Memory Card (128 to 512 MB) 97033 to 35 1 With PC card adapter Application Software AP240 1

r 97080 10 rolls

Part NumberMinimum Order Qt

A 96032 1

9803

) )

9100

9101

11D-sub 9 pin

9101

9701

y Remarks

See the option codes for a choice of probe kits. Applicable to CE or UL

See the option codes for a choice of probe kits. Not applicable to CE and UL

See the option codes for a choice of probe kits Applicable to CE. Not applicable to UL.

Not applicable to CE and U 1 se

31 set

With 1 thermal paper roll and 1 battery pac

TIP

Keep the packing box in case you need to transport the instrument.

IM CW120-E

Housing CW120/121 and Accessories

The optional carrying case can accommodate the CW120 or CW121 main unit with its current-sensing clamp-on probes and voltage probes connected to the unit. The case can also hold such accessories as manuals and PC cards, and so is useful for transporting a complete set of tools necessary for measurement.

The optional meter case can be used as a stand during measurement as shown below right. It also has a magnetic rear plate and so can be stuck to the door of a power distribution panel or the like.

Note: Keep the meter case away from objects vulnerable to a magnetic field, such as floppy disks.

Manual

Clamp-on current probes

Checking Items in the Package

Voltage probes

CW120/121 main unit

Carrying Case Meter case

Adjust the Velcro fastener.

IM CW120-E

Precautions for Safe Use of the Instrument

When operating the instrument, be sure to observe the cautionary notes given below to ensure correct and safe use of the instrument. If you use the instrument in any other way than instructed in this manual, the instrument’s protective measures may be impaired. Yokogawa is by no means liable for any damage resulting from use of the instrument in contradiction to these cautionary notes. The following safety symbols are used in the instrument and this manual.

Danger! Handle with Care.

This symbol indicates that the operator must refer to an explanation in the instruction manual in order to avoid risk of injury or death of personnel or damage to the instrument.

Direct Current

This symbol indicates DC voltage/current.

Alternating Current

This symbol indicates AC voltage/current.

This symbol indicates On (power).

OFF

This symbol indicates Off (power).

Double Insulation

This symbol indicates double insulation.

WARNING

Indicates a hazard that may result in the loss of life or serious injury of the user unless the described instruction is abided by.

CAUTION

Indicates a hazard that may result in an injury to the user and/or physical damage to the pr oduct or other equipment unless the described instruction is abided by.

NOTE

Indicates information that is essential for handling the instrument or should be noted in order to familiarize yourself with the instrument’s operating procedures and/or functions.

TIP

Indicates information that complements the present topic.

SEE ALSO

Indicates the reference location(s) for further information on the present topic.

IM CW120-E

Precautions for Safe Use of the Instrument

Strictly observe the following cautionary notes in order to avoid the risk of injury or death of personnel or damage to the instrument due to such hazards as electrical shock.

WARNING

● Removal of Case from the Instrument

• Do not remove the case from the instrument or disassemble/modify the instrument itself.

• Some parts of the inside of the instrument contain high-voltage and, therefore, access to the internal assembly is extremely hazardous. For inspection and/or adjustment of the internal assembly, contact the vendor from which you purchased the instrument.

● Use of the Instrument in a Gas Atmosphere

Do not operate the instrument in a location where any flammable or explosive gas/vapor is present. It is extremely hazardous to operate the instrument in such an atmosphere.

● Inspection of Power Source

• Before turning on the instrument, always make sure the voltage of the power source to be applied matches the instrument’s supply voltage.

● Use of Clamp-on Current Probes

•When using clamp-on current probes, keep the circuit voltage below 600 V AC in order to avoid possible short-circuits or accidents resulting in injury or death.

• Ensure that the rated current of the circuit you measure matches the rating of the current probe.

•Avoid using the instrument if it has been exposed to rain or moisture or if your hands are wet.

• Do not use clamp-on current probes with any non-insulated conductors.

● Measures In Case of Anomalies

If the instrument begins to emit smoke, becomes too hot, or gives off an un usual smell, immediately turn it off and disconnect the power cord from the outlet. Also turn off power to the object under measurement that is connected to the instrument’s input terminals. Never attempt to use the instrument again. If any such anomalies as noted above occurs, contact the vendor from which you purchased the instrument. Do not attempt to repair the instrument yourself, as doing so is extremely dangerous.

● Handling of Power Cord

• Use only the cord supplied from Yokogawa M&C to prevent electric shocks and fire.

• Do not place any load on the power cord or allow the power cord to come into accidental contact with any heat source. When unplugging the power cord from the outlet, hold its plug, rather than holding and pulling the cord itself.

• If the power cord is damaged, contact the vendor fr om which y ou purchased the instrument.

● Fuses

Fuses built into this instrument for protection cannot be replaced b y the user. When an y b uiltin fuses need to be replaced such as because they have blown, contact the vendor from which you purchased the instrument.

IM CW120-E

Utilisation en Toute Securite

Les précautions suivantes doivent être prises pendant l'exploitation, la maintenance et les réparations. YOKOGAWA ne pourra en rien être déclaré responsable si ces précautions ne sont pas respectées par l'utilisateur.

● Symboles utilisés sur les appareils et dans les Manuels d'instruction.

Explication: ce symbole indique que l'opérateur doit se reporter à une explication donnée par le manuel d'instruction afin d'éviter un accident au personnel ou de protéger l'appareil.

Courant continu: Ce symbole indique une tension/intensité C.C. Courant alternatif: Ce symbole indique une tension/intensité C.A. MARCHE: Ce symbole indique la mise sous tension.

ARRET: Ce symbole indique la mise hors tension. Double isolation: Ce symbole indique une double isolation.

AVERTISSEMENT Indique un danger. Attire l'attention sur une utilisation, sur une procédure qui pourraît être dangereuse

pour le personnel. ATTENTION Indique un danger. Attire l'attention sur une utilisation, sur une procédure qui pourraît être préjudiciable

au produit.

IM CW120-E

Utilisation en Toute Securite

AVERTISSEMENT

● Retrait du boîtier de l'instrument

• Ne pas retirer le boîtier de l'instrument et ne pas essayer non plus de démonter/modifier l'instrument lui-même.

•L'instrument renferme des composants parcourus par des tensions élevées. Il est donc extrêmement dangereux d'accéder à ses circuits internes. Pour vérifier et/ou régler les circuits internes, contacter le revendeur auprès duquel a été acheté l'instrument.

● Utilisation de l'instrument dans une atmosphère gazeuse Ne pas utiliser l'instrument dans un endroit qui renferme des gaz/vapeurs inflammables ou explosifs.

Il est extrêmement dangereux d'utiliser l'instrument dans une telle atmosphère.

● Vérification de la source d'alimentation

•Avant de mettre l'instrument sous tension, toujours s'assurer que sa tension correspond à celle de la source d'alimentation.

● Utilisation des sondes d'intensité à pince

• Lors de l'utilisation des sondes d'intensité à pince, maintenir la tension du circuit au-dessous de 600 V CA afin d'écarter tout risque de court-circuit ou d'accident susceptible de provoquer des blessures qui peuvent éventuellement s'avérer mortelles.

• Assurez-vous d'utiliser un capteur de courant dont le calibre correspond au niveau d'intensité à mesurer.

• Eviter d'utiliser l'instrument si celui-ci a été exposé à la pluie ou à l'humidité, ou encore si vos mains sont humides.

• Ne pas utiliser les sondes d'intensité à pince avec des conducteurs non isolés.

● Mesures à prendre en cas d'anomalies Si l'instrument est brûlant, dégage de la fumée ou une odeur inhabituelle, le mettre immédiatement

hors tension et débrancher le cordon d'alimentation de la prise secteur. Mettre également hors tension le circuit sur lequel est effectuée la mesure et qui est raccordé aux bornes d'entrée de l'instrument. Ne surtout pas essayer d'utiliser l'instrument à nouveau. Si l'une de ces anomalies est détectée, contacter le revendeur auprès duquel a été acheté l'instrument. Ne pas essayer de le réparer soimême, car cela est extrêmement dangereux.

● Manipulation du cordon d'alimentation

• Afin de prévenir tout feu ou choc électrique, n'utilisez que le cordon fourni par Yokogawa M&C.

• Ne déposer aucune charge sur le cordon d'alimentation et éviter tout contact fortuit entre celui-ci et

une source de chaleur. Pour débrancher le cordon de la prise secteur, tirer sur sa fiche, mais jamais sur le fil proprement dit. Si le cordon d'alimentation est endommagé, contacter le revendeur auprès duquel a été acheté l'instrument.

● Fusibles Les fusibles de protection montés sur cet instrument ne peuvent pas être remplacés par l'utilisateur.

Si, par suite de claquage, un fusible doit être remplacé, veuillez contacter le vendeur auprès de qui vous avez acheté l'instrument.

IM CW120-E

Introduction ..............................................................................................................1

Checking Items in the Package .............................................................................. 2

Precautions for Safe Use of the Instrument .......................................................... 6

Chapter 1. Product Overview...............................................................................1-1

1.1 Product Overview ........................................................................................1-1

Chapter 2. Components and Indications ............................................................ 2-1

2.1 Front Panel and Connector Block ............................................................... 2-1

2.2 Connecting Input Signals ............................................................................ 2-3

2.3 Operation Keys and Display........................................................................ 2-5

2.4 Overrange and Other Marks Shown during Measurement.......................... 2-6

Chapter 3. Precautions for Safe Measurement ..................................................3-1

3.1 Handling Precautions .................................................................................. 3-1

3.2 Installation Procedure.................................................................................. 3-3

3.3 Maintaining High Precision of Measurement............................................... 3-5

Chapter 4. Connecting Power Supply and Turning Power On/Off ...................4-1

4.1 When Using AC Power Supply.................................................................... 4-1

4.2 When Supplying Power from Voltage Input................................................. 4-3

4.3 Startup Screens........................................................................................... 4-4

4.4 Basic Operation Flow .................................................................................. 4-6

Chapter 5. Wiring ..................................................................................................5-1

5.1 Precautions for Wir ing the Circuit under Test .............................................. 5-1

5.2 Diagrams of Basic Wiring............................................................................ 5-2

5.3 Wiring the Circuit under Test with External VT/CT ...................................... 5-4

5.4 Indication and Change of Wiring Method .................................................... 5-5

5.5 Wiring Check Function ................................................................................ 5-6

Chapter 6. Setting Ranges and Wiring Method ..................................................6-1

6.1 Ranges and Display Digits .......................................................................... 6-1

6.2 Changing Voltage Range Setting ................................................................ 6-6

6.3 Changing Current Range Setting ................................................................ 6-7

6.4 Changing Wiring Method Setting............................................................... 6-10

Chapter 7. Making Settings..................................................................................7-1

7.1 Setting Items and Item Selection................................................................. 7-1

7.2 Setting Each Item........................................................................................ 7-4

7.3 Setting Name of Measured-data File......................................................... 7-33

IM CW120-E

Contents

Chapter 8. Instantaneous Value Measurement..................................................8-1

8.1 Measuring Instantaneous Values ................................................................ 8-1

8.2 Switching Display Contents......................................................................... 8-2

8.3 Saving Data................................................................................................. 8-5

8.4 Frequency Measurement ............................................................................ 8-8

8.5 Sampling Cycle and Integration Cycle ........................................................ 8-9

Chapter 9. Electric Energy Measurement ........................................................... 9-1

9.1 Measuring Electric Energy .......................................................................... 9-1

9.2 Starting and Stopping Integration................................................................ 9-3

9.3 Switching Display Contents....................................................................... 9-10

9.4 Saving Data............................................................................................... 9-13

9.5 Backup Memory ........................................................................................ 9-16

9.6 External Control Input/Output.................................................................... 9-19

9.7 Meter Actions upon Power Failure and Recovery ..................................... 9-22

Chapter 10. PC Card ...........................................................................................10-1

10.1 PC Card Specifications ............................................................................. 10-1

10.2 Inserting and Removing PC Card.............................................................. 10-2

10.3 Storage Capacity....................................................................................... 10-3

10.4 Formatting PC Card .................................................................................. 10-4

10.5 Saving and Loading from/to PC Card........................................................ 10-5

10.6 Interface with Personal Computer............................................................. 10-7

Chapter 11 Communication Functions ............................................................ 11-1

11.1 RS-232 ...................................................................................................... 11-1

11.2 RS-485 ...................................................................................................... 11-6

11.3 Data Format .............................................................................................. 11-9

Chapter 12. Auxiliary Functions ........................................................................12-1

12.1 Convenient Functions ................................................................................ 12-1

12.2 Using Optional Printer ............................................................................... 12-3

Chapter 13. Troubleshooting ............................................................................. 13-1

13.1 Corrective Measures in Case of Failure.................................................... 13-1

13.2 Error Codes............................................................................................... 13-2

13.3 Disposing the Product ............................................................................... 13-3

Chapter 14. Specifications .................................................................................14-1

14.1 Specifications of CW120/121 .................................................................... 14-1

14.2 Specifications of Clamp-on Current Probes .............................................. 14-9

Appendix 1.Circuit Block Diagram ............................................................... App1-1

Appendix 2. Communication Commands....................................................App2-1

1. Commands .......................................................................................... App2-2

1.1 Messages..............................................................................................App2-2

1.2 Commands............................................................................................App2-4

1.3 Response .............................................................................................. App2-5

1.4 Data.......................................................................................................App2-6

1 2 3 4 5 6 7 8

9 10 11 12 13 14

App

Index

IM CW120-E

Contents

1.5 Messages on RS-485............................................................................App2-8

1.6 Communication Commands ..................................................................App2-9

1.7 Detailed Description of Communication Commands........................... App2-12

1.7.1 COMMunicate Group ............................................................... App2-12

1.7.2 SYSTem Group ........................................................................App2-13

1.7.3 INTEgrate Group...................................................................... App2-15

1.7.4 MEASure Group....................................................................... App2-17

1.7.5 STATus Group..........................................................................App2-17

1.7.6 MEMOry Group........................................................................App2-18

1.7.7 CARD Group............................................................................App2-18

1.7.8 Common Group .......................................................................App2-19

2. Error Messages ............................................................................... App 2-20

3. Command Effectiveness Tables....................................................... App 2-24

Appendix 3. File Structures and Data Items Printed .................................App3-1

1. Overview............................................................................................ App 3-2

2. Measured Data .................................................................................. App 3-3

2.1 File Format ........................................................................................... App 3-3

2.1.1 File Identifier .............................................................................App 3-3

2.1.2 File Type ................................................................................... App 3-3

2.1.3 Measurement Mode .................................................................. App 3-3

2.1.4 Data Field Titles and Data Formats ..........................................App 3-4

2.1.5 Records of Power Failure/Restoration Information ................... App 3-5

2.2 Print Format ..........................................................................................App 3-6

2.2.1 Print Item Titles and Data Formats ........................................... App 3-6

3. Settings.............................................................................................. App 3-8

3.1 File Format ........................................................................................... App 3-8

3.2 Output Format and Data Values ........................................................... App 3-9

3.3 Print Format........................................................................................ App 3-11

4. Automatic File Naming ..................................................................... App 3-12

Appendix 4. Reactive Power ........................................................................App4-1

Index............................................................................................................... Index-1

IM CW120-E

Chapter 1. Product Overview

1.1 Product Overview

The CW120/121 clamp-on power meters measure the fundamental electric power factors, namely, instantaneous power-related values and electric energy (watt-hours).

• CW120: Supports single-phase two-wire, single-phase three-wire, three-

phase three-wire, and single-phase tow-wire × 2 circuits.

• CW121: Supports single-phase two-wire, single-phase three-wire, three-

phase three-wire, three-phase four-wire, single-phase tow-wire × 2, and single-phase tow-wire × 3 circuits.

The following explains the features of the CW120/121, shows a schematic diagram of their functions, and describes the contents displayed on the screen in each measurement mode.

Features

● A Wealth of Functions

• Fast data saving for a long time: Data can be saved at 1-second intervals at fastest. A PC card slot for large removable memories such as flash ATA and compact flash cards allows measurement over a long time.

• Instantaneous value saving: Simply pressing the SAVE key will save the measured values.

•Wiring error check: The connections are checked and any error is displayed before the start of measurement.

Product Overview

IM CW120-E

● Broad Ranges

• Voltage range: 150/300/450 V

• Current range: 4 types of clamp-on probes can be used.

96033 clamp-on probe: 5/10/20/50 A 96030 clamp-on probe: 20/50/100/200 A 96031 clamp-on probe: 50/100/200/500 A 96032 clamp-on probe: 200/500/1000 A

● Ease of Data Processing and Communication

Data can be saved to a PC card. Via communication, data can be transferred to a personal computer and the measurement conditions can be set from a computer. As the communication interface, you can choose (when ordering) RS-232 or RS-485; the RS-485 interface allows multiple CW120s and CW121s to be connected on the same line for remote monitoring.

1-1

1.1 Product Overview

● Compact Design

• The CW120/121 are sufficiently compact to be installed inside a cubicle or

power distribution panel during measurement.

• The 96033 current-sensing probe with a 5 to 50 A range is designed for

use in a narrow space, so is useful for measurement inside a power distribution panel with dense wiring.

● Easy-to-see Display Screen

Despite the compact body, the large back-lit LCD enables easy measurement in a dark place.

1-2

IM CW120-E

● Schematic Function Diagram

Power-on

1.1 Product Overview

Product Overview

Measurement screen

key

Chapter 9

Electric energy (watt-hour) measurement

Start of integration

7.2.8 Setting integration start time

7.2.9 Setting integration stop time

End of integration

Data saving

Auto-saving

7.2.7 Setting output interval File: AWTH000.CSV

External control terminals

Input Output

7.2.11 Selecting communication device

key

Setting device number

7.2.1 Loading/saving settings

7.2.2 Deleting file and formatting PC card

7.2.3 Clearing electric energy count (watt-hours)

7.2.4 and resetting system Copying and clearing backup memory

7.2.5 contents Setting date

7.2.6 Setting output interval

Chapter 8

Instantaneous value measurement

Data saving

key

7.2.7 Setting integration start time

7.2.8 Setting integration stop time

7.2.9 Setting whether to save data to PC card

7.2.10 Selecting communication device

7.2.11 Making communication settings

7.2.12 Setting communication protocol

7.2.13 Setting VT ratio

7.2.14 Setting CT ratio

7.2.15 Selecting probe to be used

7.2.16 Setting decimal point and unit of electric

7.2.17 energy (watt-hours)

Saving settings

File: MWTH000.CSV

Communication interface (chosen when ordering)

7.2.2 Loading/saving setting File: WTH000.SET

RS-485RS-232

PC Printer PC

Setting screens

Chapter 7

PC card

7.2.10 Setting whether to save data to PC card

IM CW120-E

● On-screen Information (Measured Data)

There are two measurement modes: instantaneous measurement and electric energy measurement. In the latter mode, the power is continuously measured and integrated during the preset start and stop times.

Instantaneous value measurement

Item Unit Displayed Name

Rms voltage V V1, V2, V3 (differs depending on the wiring method) Rms current A A1, A2, A3 (differs depending on the wiring method) Active power W W, W1, W2, W3 (differs depending on the wiring

method)

Reactive power Var Var, Var1, Var2, Var3 (differs depending on the wiring

method)

Power factor — PF, PF1, PF2, PF3: PowerFactor

(differs depending on the wiring method)

Frequency Hz Hz (input frequency of V1)

1-3

1.1 Product Overview

Phase Wires

Single-phase two wires (1∅2W) Single-phase three wires (1∅3W)

Three-phase three wires (3∅3W) Three-phase four wires (3∅4W)

Single-phase tow-wires

2 (1∅2W×2)

Single-phase tow-wires

3 (1∅2W×3)

Electric energy measurement

Item Unit Displayed Name

Active electric energy Wh Wh, Wh1, Wh2, Wh3

Regenerative electric energy Wh Only saved; not displayed Six items of instantaneous value measurement

(differs depending on the wiring method)

The screen changes sequentially each time a cursor-movement (UP, DOWN, LEFT, or RIGHT) key is pressed as follows (display contents differ depending on the wiring method):

Var

A1 A2 V3

A1 W1 W2

Var1 Var2

W1 W2 W3

Var1 Var2 Var3

Displayed Item

Screen

PF Hz

Var

A3 PF1 PF2

Hz PF1

PF2 PF3

Screen

TIME

PF Hz

Var Wh1 Wh2

TIME

Wh1 Wh2 Wh3

TIME

Screen

TIME

PF Hz

Screen

TIME

Display Position

Upper row Lower row Upper row Lower row Upper row Lower row

Upper row

Lower row

Upper row

Lower row

Screen

V1 A1 V1 V2 V1 V2

V1 A1

A1 A2 A3

Screen

1-4

IM CW120-E

Chapter 2. Components and Indications

2.1 Front Panel and Connector Block

● Dimensions

Connector Block

Unit: mm (approx. inches)

Front View Side View

161 (6.3)

Components and Indications

IM CW120-E

117 (4.6) 51 (2.0)

2-1

2.1 Front Panel and Connector Block

● Connector Block

Voltage input terminals Current input terminals

CW120: Supports from single-phase two-wire to three-phase three-wire circuits

Voltage input terminals: N, V1, V2 Current input terminals: CH1, CH2

CW121: Supports from single-phase two-wire to three-phase four-wire circuits

Voltage input terminals: N, V1, V2, V3 Current input terminals: CH1, CH2, CH3

● Side Panels

PC card eject button PC card eject button

PC card slot

RS-232 connector

External control terminals

PC card slot

RS-485 screw terminals

Power switch Power supply connector Power switch Power supply connector

Model with RS-232 interface Model with RS-485 interface

RS-232 interface

RS-232 connector : Used to connect to a PC or printer

(optional).

Internal control input (IN) terminals : Used to connect the integration

start/stop input signals.

Internal control output (OUT) terminals : Used to connect the integration

start/stop output signals.

SEE ALSO

For details of external control input/output, see Section 9.6, “External Control Input/Output.”

RS-485 interface

RS-485 screw terminals : Used to connect a shielded cable

and terminator.

SEE ALSO

For details of the RS-485 interface, see Section 11.2, “RS-485.”

2-2

IM CW120-E

2.2 Connecting Input Signals

Ring marker

Clamp-on current probe

Voltage probe (black)

Voltage probe (red)

Components and Indications

WARNING

• Thoroughly read Section 5.1, “Precautions for Wiring the Circuit under Test.”

•When connecting the CW120/121, turn off the circuit under test. It is extremely dangerous to connect or disconnect probes to/from a live circuit.

• Be extremely careful not to connect any voltage-mode circuit to the current input terminals or any current-mode circuit to the voltage input terminals. Miswiring can result in not only damage to the circuit or equipment under test but also injury to personnel.

• Do not connect any probes which are not necessary (i.e., not used) for the current measurement, even though multiple probes can be connected to the CW120/121 at the same time.

• Do not use any probe other than the clamp-on current probes or voltage probes supplied.

• Do not use a clamp-on current probe for a non-insulated conductor.

• Ensure that the rating of the clamp-on current probe you use matches the rating of the measured current.

• Before connecting a clamp-on current probe to the CW120/121, make sure the plug is inserted with the correct H/L polarities.

IM CW120-E

2-3

2.2 Connecting Input Signals

● Differentiating between Voltage Probes

Voltage probes are differentiated by color for correct connections.

• Probe for terminal N: Probe with a black alligator plug

• Probes for terminals V1 to V3: Probes with a red, yellow, or blue alligator plug

Accompanying probes

CW120: Three (black, red, and yellow) CW121: Four (black, red, yellow, and blue)

● Differentiating between Clamp-on Current Probes

Use accompanying ring markers (of four different colors) to differentiate clamp-on current probes for correct connections.

CW120: Terminals CH1 to CH2 CW121: Terminals CH1 to CH3

Use of Ring Markers

Attach ring markers of the same color to both ends of the probe cable for easy identification.

CAUTION

Be careful not to damage a probe when attaching ring markers.

2-4

IM CW120-E

2.3 Operation Keys and Display

Integration status LED indicator

V RANGE key

A RANGE key

WIRING key

LIGHT key

● Keys

Components and Indications

Key Symbol DescriptionName

Used to set and change the voltage range.

Used to set and change the current range.

Used to set and change the wiring method (phase lines).

Also used to check the wiring. Pressing this key for three seconds or more accesses the wiring check screen.

Switches on/off the backlight of the LCD. Also used to lock and unlock the keys. Pressing this key

for three seconds locks the keys. To unlock, press the key again for three seconds or more.

SAVE key

MEAS/SET key

START&STOP key

ENTER key

ESC (escape) key

Cursor movement keys (UP/DOWN/LEFT/RIGHT keys)

Integration status LED indicator: Lit when the integration is carried out, and flashes when it is on stand-by.

IM CW120-E

Saves the measured data during instantaneous value measurement. Switches over the display between the measurement and setting screens.

Starts and stops integration.

Confirms an entry such as a change to a setting.

Cancels a setting and returns to the preceding screen. Also used to clear the electric energy count (watt-hours).

Pressing this key for three seconds or more accesses the screen for clearing the electric energy count.

In measurement screen: Switches the display contents. In setting screen: Changes the selection or number, or

moves the cursor position (flashing digit) over digits.

2-5

2.4 Overrange and Other Marks Shown during Measurement

WARNING

When the overrange mark appears with the range set to a maximum, it means that the input exceeds the maximum allowable level of the CW120/121. Do not apply an input level higher than the maximum allowable input level.

CAUTION

When measuring an input signal level exceeding the rated range, use a voltage transformer (VT) or current transformer (CT). When using a VT or CT, thoroughly read Section 5.3, “Wiring the Circuit under Test with External VT/CT.”

● Overrange Indications

: Indicates an overvoltage.

This mark appears in the following conditions. 150/300 V range: If the sampled value exceeds 200% of the rated

voltage or if the rms value of the measured voltage exceeds 110% of the rated range

450 V range: If the sampled value exceeds 156% of the rated

voltage or if the rms value of the measured voltage exceeds 110% of the rated range

: Indicates an overcurrent.

This mark appears if the sampled value exceeds 300% of the rated current or if the rms value of the measured current exceeds 110% of the rated range.

TIP

The mark appears when any one of the input signals from terminals V1 to V3 satisfies the conditions noted above.

The mark appears when any one of the input signals from terminals CH1 to CH4 satisfies the conditions noted above.

indication

The CW120/121 show instead of a usual number representing the measured value if any one of the following conditions is met. The number representing the measured value exceeds 9999, the maximum number displayed.

2-6

IM CW120-E

2.4 Overrange and Other Marks Shown during Measurement

Voltage - 150/300 V range: If the sampled value exceeds 200% of the rated voltage or if the rms value of the measured voltage exceeds 130% of the rated range

Voltage - 450 V range: If the sampled value exceeds 156% of the rated voltage or if the rms value of the measured voltage exceeds 110% of the rated range

Current: If the sampled value exceeds 300% of the rated voltage or if the rms value of the measured voltage exceeds 130% of the rated range

● Indications When the Measured Value Is Too Small

Components and Indications

Displayed Item

Voltage Current Active power Reactive power Active electric energy

Displayed Item

Reactive power

Power factor

Frequency

Condition

≤1.5 V ≤0.4% of rated range ≤0.17% of rated range ≤0.17% of rated range ≤0.17% of rated range

Condition

V1 input ≤10% of rated range; or frequency ≤40 Hz or ≥70 Hz

The voltage or current is displayed as ; or V1 input ≤10% of rated range; or frequency

≤40 Hz or ≥70 Hz ≤40 Hz or ≥70 Hz

Indication

0 V 0 A 0 W 0 Var 0 Wh (integration stopped)

Indication

---- Var

---- PF

---- Hz

TIP

Even when an instantaneous value is displayed as , the integration calculation is carried out continuously. The accuracy of the electric energy value, however, is undefined in this case.

IM CW120-E

2-7

2.4 Overrange and Other Marks Shown during Measurement

● Indications of Setting Items

Mark appearing during setting mode:

Setting Item Displayed Mark

1. Device number

2. Loading and saving of settings

3. Deletion of measured-data file and formatting of PC card

4. Clearance of electric energy count (watt-hours) and resetting of system

5. Copying and clearance of backup memory

6. Date

7. Output interval

8. Integration start date and time

9. Integration stop date and time

10. Whether to save data to PC card

11. Selection of communication device

12. Communication settings

13. Communication protocol setting

14. VT ratio setting

15. CT ratio setting

16. Probe selection

17. Decimal position and unit selections for electric energy (watt-hours)

● Indications during Measurement

Displayed Mark

Lights when integration is carried out; flashes when integration is on standby. Lights when integration is controlled by external signals. Lights when PC card memory is full. Lights when the backup memory contains data. Lights when the battery voltage is low. Lights when the keys are locked. Lights when data saving to the PC card is enabled; flashes during access to the PC card. Flashes during access to the PC when a PC is selected as the communication device. Flashes during access to the printer when a printer is selected as the communication device. Lights when the VT ratio is set at a value other than 1. Lights when the CT ratio is set at a value other than 1.

2-8

Indications for current settings of voltage range, current range, and wiring method:

Wiring method Voltage range

Current range

IM CW120-E

2.4 Overrange and Other Marks Shown during Measurement

● Meanings of Messages

Displayed Message Meaning

Appears during standby of integration when set to start at a set date and time.

Appears during standby of integration when a past point of time is set as the integration start time and date and integration will begin at the nearest appropriate time (determined by the output interval).

Appears when integration has finished normally with the set integration start/stop dates and times.

Appears when a power failure has occurred (or the power has been turned off) during standby or integration.

Appears when the backup data is copied from the backup memory to the PC card.

Appears when a PC card is not inserted.

Shows the file number and data record number when saving measured instantaneous values.

Shows the file number when integration begins in the case that data saving to a PC card is enabled but the filename is not specified.

Appears when integration begins in the case that data saving to a PC card is enabled and the filename is specified. The digits following “FILE” indicate “defined.”

Components and Indications

IM CW120-E

2-9

Chapter 3. Precautions for Safe Measurement

3.1 Handling Precautions

If you are a first-time user, be sure to read “Precautions for Safe Use of Instrument” on pages 4 and 5, Section 5.1, “Precautions for Wiring the Circuit under Test,” and Section 5.3, “Wiring the Circuit under Test with External VT/ CT.”

● Do not place any load on the instrument.

Do not place any other equipment of a vessel filled with water on the instrument. Otherwise, the instrument may become defective.

● Moving the instrument

Before moving the instrument, make sure the power cord and all other cables are disconnected.

● Input Terminals

Do not bring any electrified substance close to the signal terminals. Otherwise, the internal circuitry may be destroyed. Do not apply any mechanical shock to the signal terminals. Otherwise, such impact may be transformed into electrical noise and input to the instrument.

Precautions for Safe Measurement

● Protection of Case and Operation Panel

Do not spray any volatile chemical on the case or operation panel. Do not leave any rubber or vinyl product in contact with the instrument for a prolonged period. Otherwise, the instrument may be discolored or deformed.

● Cleaning

When cleaning the case and/or operation panel, disconnect the power cord from the outlet. Then, wipe the surfaces of the case and/or operation panel with a soft clean cloth. Do not use chemicals such as benzine or paint thinner. Otherwise, the instrument may be discolored or deformed.

● Display Screen

When the instrument is shipped from the factory, the display screen is covered with a protective film. Remove the film before you begin using the instrument.

IM CW120-E

3-1

3.1 Handling Precautions

● After Use

After use, disconnect the power cord from the outlet.

Precautions for Use of the Clamp

CAUTION

• The clamping CT (current transformer) is precision assembled to ensure high performance. When using the clamp, do not apply any intense mechanical shock, vibration or force to the clamping CT.

• If dust or any other foreign matter gets in the clamping CT, do not shut the clamping cores tight. First remove the dust and then make sure the clamping cores on both sides close smoothly.

3-2

IM CW120-E

3.2 Installation Procedure

Install the CW120/121 in a location that satisfies the following conditions.

● Indoors

● Ambient Temperature and Humidity

• Ambient temperature: 0°C to 50°C

• Ambient humidity: 5 to 85 % RH (no condensation) When it is applied to UL.

• Ambient temperature: 0°C to 40°C

• Ambient humidity: 5 to 85 % RH (no condensation) Maximum relative humidity 80 % RH for temperature up to 31 °C decreasing linearly to 50 % RH relative humidity at 40 °C.

● Altitude of Location

•Altitude: 2000 m or less

● Measurement Category (CAT.)

The measurement category of the CW120/121 is III.

Measurement

3.3 Maintaining High Precision of Measurement

To achieve a high precision of measurement, use the CW120/121 under the following conditions.

• Ambient temperature: 23° ±5°C

• Ambient humidity: 35 to 75% RH (no condensation)

When installing the CW120/121 in a location where the ambient relative humidity is 30% or less, use such equipment as an anti-static mat to prevent electrostatic discharge.

If you move the CW120/121 from an area of low temperature and humidity to an area of high temperature and humidity or if there is a sudden change in the ambient temperature, condensation may occur in the meter. If this happens, let the meter stand for at least one hour to allow it to adapt to the new ambient temperature and for condensation to evaporate. Then, start operating the meter.

● Relationship between Clamp and Conductor

1. When performing a measurement, hold the clamp-on probe so that the conductor cable runs through the center of the clamping CT.

2. Ensure that the orientation of the clamp to the direction of the conductor cable (from the power supply to the load) is correct, as shown in the figure.

3. Ensure that the clamping CT is properly closed.

Precautions for Safe Measurement

IM CW120-E

Conductor cable

Joint section

Clamping CT

Power supply source side

Load side

3-5

Chapter 4. Connecting Power Supply and Turning Power On/Off

4.1 When Using AC Power Supply

● Before Connecting Power Supply

There is a danger of electric shock or damage to the meter. Observe the following warning notes.

WARNING

• Use only the dedicated power cord supplied by the manufacturer.

• Before connecting the power cord, make sure the power-source voltage matches the rated supply voltage.

• Before connecting the power cord, also make sure the power switch of the CW120 or CW121 is turned off.

• If the CW120 or CW121 will not be used for a prolonged period, disconnect the power cord from the outlet.

• Do not place any load on the power cord or allow the power cord to come into accidental contact with a heat source.

• Be sure to hold the plug of the power cord, rather than holding and pulling the cord itself, when disconnecting it from the outlet.

● Procedure for Connecting Power Cord

Follow the steps below to connect the power cord.

1. Make sure the power switch of the CW120/121 is turned off.

2. Plug one end of the power cord supplied with the CW120/121 into the power supply jack on the side of the CW120/121.

3. Plug the other end of the power cord into a power outlet that meets the requirements below.

Required Power Ratings

Rated supply voltage 100 to 240 V AC Allowable supply voltage range 90 to 264 V AC Rated power supply frequency 50 or 60 Hz Allowable supply frequency range 48 to 63 Hz Maximum power consumption 8 VA (at 240 V AC)

Connecting Power Supply and Turning Power On/Off

IM CW120-E

4-1

4.1 When Using AC Power Supply

NOTE

•When plugging and unplugging the power cord into/from the CW120 or CW121, ensure that the PC card eject button is depressed.

• The CW120 or CW121 will not work if the fuse built into the power supply circuit of the CW120 or CW121 has blown.

• Built-in fuses cannot be replaced by the user . For replacement, contact the vendor fr om which you purchased the instrument.

4-2

IM CW120-E

4.2 When Supplying Power from Voltage

Input

NOTE

The 98030 power supply cable is not applicable to CE and UL.

● Before Connecting Power Supply

There is a danger of electric shock or damage to the meter. Observe the following warning notes.

WARNING

• Use only the optional power cable (part No. 98030) supplied by the manufacturer.

•Make sure the voltage of the circuit to be measured matches the rated supply voltage (i.e., 100 to 240 V AC).

• Before connecting to the circuit to be measured, make sure the power to the circuit is turned off.

• Before connecting the power cable, make sure the power switch of the CW120 or CW121 is turned off.

• Do not place any load on the power cord or allow the power cord to come into accidental contact with a heat source.

● Procedure for Connecting 98030 Power Supply Cable

Follow the steps below to connect the 98030 power supply cable.

1. Make sure the power switch of the CW120/121 is turned off.

2. Insert the plug of the 98030 power supply cable into the power supply jack on the side of the CW120/121.

3. Insert the black banana plug of the power supply cable into terminal N of the CW120/121, and red banana plug into terminal V1.

4. Connect the black plug of the voltage probe to the black banana plug, and the red plug of the probe to the red banana plug.

5. Check that the power to the circuit to be measured is turned off, and then connect the voltage probes to the circuit.

Connecting Power Supply and Turning Power On/Off

IM CW120-E

Black

Voltage probe(Black)

Red

Voltage probe(Red)

4-3

4.3 Startup Screens

Upper: Model number

Lower: V ersion number

Upper: Rms voltage

Lower: Rms current

When you turn on the power to the CW120 or CW121, the screens shown in (1) to (3) below appear sequentially in order.

(1) All-segment On

All segments light for approximately 2 seconds, then the screen changes to the model and version display.

(2) Model and Version Display Screen

4-4

While the display is turning on all segments and showing the model and version numbers, the CW120/121 performs a self-test. If no error is found, the measurement screen appears.

(3) Measurement Screen

Example of measurement screen

IM CW120-E

● Self-test Details and Error Handling Test Items and Errors

4.3 Startup Screens

No.

1 2

4 5

Test Item

Backup SRAM check EEPROM check

Real-time clock check

Setting check External memory controller check

Error Number(s)

If an error is found during the self-test, an error number is displayed. Confirm the error number and press any key, then the screen changes to the measurement screen.

NOTE

• If an error is found with any of test item Nos. 1, 3, and 4 (backup SRAM check, real-time clock check, and setting check), the settings, date, and time will be initialized.

• The above situation may occur when the backup battery has become flat. When the (low battery) sign is displayed on the screen, the backup battery needs to be replaced.

• The backup battery cannot be replaced by the user . For replacement, contact the vendor from which you purchased the instrument.

• The backup battery life is about 10 years.

Connecting Power Supply and Turning Power On/Off

SEE ALSO

For details of errors and the countermeasures, see Chapter 13, “Troubleshooting.”

IM CW120-E

4-5

4.4 Basic Operation Flow

Connect power supply to CW120/121

Turn on power to CW120/121

Startup screens Measurement screen

key

Setting screen

key

Measurement screen

: Calls up wiring setting

key

: Calls up voltage range setting

key

: Calls up current range setting

key

Chapter 4

When no setting is needed

Chapter 7

Chapter 6

4-6

Perform wiring

: Check wiring for error

key

(press 3 sec)

key

Check result screen

key

Measurement

Instantaneous value measurement

Electric energy measurement

Chapter 5

When skipping wiring check

Chapter 5

Chapter 8 Chapter 9

IM CW120-E

Chapter 5. Wiring

5.1 Precautions for Wiring the Circuit under Test

WARNING

•When wiring the CW120 or CW121, or when it is turned off, turn off the circuit under test. It is highly dangerous to connect or disconnect voltage or clamp-on current probes without first turning off the circuit under test.

• Be extremely careful not to connect any voltage-mode circuit to the current input terminals or any current-mode circuit to the voltage input terminals. Miswiring can result in not only damage to the circuit under test or equipment under test but also injury to personnel.

• Do not apply any input level higher than the following to the voltage or current input terminals (the upper limit differs depending on the probe used):

Maximum allowable input (continuous)

Voltage input: 495 Vrms Current input –for 96033 probe: 130 Arms

for 96030 probe: 250 Arms for 96031 probe: 625 Arms for 96032 probe: 700 Arms (1000 Arms for 5 minutes)

Input ratings for each range

Voltage input: 150/300/450 V Current input –for 96033 probe: 5/10/20/50 A

for 96030 probe: 20/50/100/200 A for 96031 probe: 50/100/200/500 A for 96032 probe: 200/500/1000 A

Wiring

SEE ALSO

For details, see Chapter 14, “Specifications.”

WARNING

• If using an external voltage transformer (VT) or current transformer (CT), make sure the transformer can adequately withstand the voltage being measured. Be extremely careful not to allow the secondary stage of the CT to become open-circuited while the CT is being electrified. Otherwise, a high-voltage may develop on the secondar y stage, causing extreme danger.

• The maximum allowable input voltage range of the external control input terminals is -0.5 to

5.5 V. Do not apply voltages exceeding this range, otherwise the input circuitry may be damaged. (When wiring the input terminals, ensure that you wire the right terminals.)

• Do not use any probe other than the voltage probes supplied with the CW120/121 or dedicated clamp-on current probes.

• Do not use a clamp-on probe with any non-insulated conductors.

IM CW120-E

5-1

5.2 Diagrams of Basic Wiring

This section explains the methods of basic wiring using illustrations.

Single-phase two wires (1∅2W)

SOURCE LOAD

1 N

NV1 CH1

Single-phase three wires (1∅3W)

SOURCE LOAD

1 N 2

NV1V2 CH1 CH2

Three-phase three wires (3∅3W)

SOURCE LOAD

1 2 3

5-2

NV1V2 CH1 CH2

Three-phase four wires (3∅4W): Only for CW121

SOURCE LOAD

N 1 2 3

NV1V2V3 CH2CH1 CH3

Single-phase tow-wires ×2 (1∅2W ×2)

SOURCE LOAD1

1 N

NV1 CH2CH1

LOAD2

IM CW120-E

5.2 Diagrams of Basic Wiring

Single-phase tow-wires ×3 (1∅2W ×3): Only for CW121

1 N

SOURCE

LOAD1

LOAD2

LOAD3

NV1 CH2CH1 CH3

The table below shows the correspondences between the voltage/current units (sets of a unit + input number) displayed on the screen and the input terminals for voltage and clamp-on current probes.

Wiring Method (Phase Lines)

Single-phase two wires (1∅2W)

Single-phase three wires (1∅3W)

Three-phase three wires (3∅3W)

Three-phase four wires* (3∅4W)

Single-phase tow-wires ×2 (1∅2W ×2)

Single-phase tow-wires* ×3 (1∅2W ×3)

* Only for CW121

Voltage Inputs

Terminals: N-V1 Units: V1

Terminals: N-V1, N-V2 Units: V1, V2

Terminals: N-V1, N-V2, N-V3 Units: V1, V2, V3

Terminals: N-V1 Units: V1

Current Inputs

Terminals: CH1 Units: A1

Terminals: CH1, CH2 Units: A1, A2

Terminals: CH1, CH2, CH3 Units: A1, A2, A3

Terminals: CH1, CH2 Units: A1, A2

Terminals: CH1, CH2, CH3 Units: A1, A2, A3

Wiring

IM CW120-E

5-3

5.3 Wiring the Circuit under Test with External VT/CT

WARNING

•When using an external current transformer (CT), be careful not to allow the secondary stage of the CT to become open-circuited while the primary stage is being electrified. Otherwise, a high-voltage may develop on the secondary stage, causing extreme danger.

•A measuring current flows through the bold lines shown in the figure below. For these lines, use wires having an adequate margin of current-carrying capacity.

If the maximum voltage or current level being measured exceeds the maximum measurement range of the CW120/121, use an external voltage transformer (VT) or current transformer (CT). This strategy enables the voltage or current levels beyond the maximum range to be measured.

When to use a VT and how?

If the maximum voltage of the circuit exceeds 450 V, connect an external VT and connect the secondary stage of the VT to the voltage input terminals.

When to use a CT and how?

If the maximum current of the circuit exceeds the following value, connect an external CT and clamp the secondary stage wire of the CT with a current probe.

96033 probe: 50 A (rated at 5/10/20/50 A) 96030 probe: 200 A (rated at 20/50/100/200 A) 96031 probe: 500 A (rated at 50/100/200/500 A) 96032 probe: 1000 A (rated at 200/500/1000 A)

Example for single-phase two wires (1∅2W)

Source Load

VT CT

V1Voltage input Current inputN CH1

Scaling

When using a VT and/or CT, you can set the VT ratio and/or CT ratio to display the readings of the primary circuit voltages and currents. (This is called the scaling function.)

SEE ALSO

For details of how to set the CT and VT ratios, see Sections 7.2.14 and 7.2.15, “Setting VT Ratio” and “Setting CT Ratio.”

5-4

IM CW120-E

5.4 Indication and Change of Wiring

Method

The abbreviations for wiring methods are labeled immediately above the screen as 1∅2W, 1∅3W, 3∅3W, 3∅4W, 1∅2W2, and 1∅2W3 (3∅4W, 1∅2W3 are not included for the CW120), and the sign on the screen indicates the wiring method currently selected in the CW120/121.

Wiring methods

WIRING

WIRING key

Wiring

IM CW120-E

To change the wiring method, press the key. Each time you press the WIRING key, the moves to change the selected wiring method.

Indication of wiring method.

<1∅2W ×2> CW120

<1∅2W ×3> CW121

CW121

5-5

5.5 Wiring Check Function

WARNING

• It is important to check the wiring for correct and safe measurement. Check the wiring with reference to Chapter 3, “Precautions for Safe Measurement,” Section 5.1, “Precautions for Wiring the Circuit under Test,” and Section 5.3, “Wiring the Circuit under Test with External VT/ CT.”

• Check the connections of voltage probes, and for clamp-on current probes, check the models (ratings), H/L polarities of the plugs and jacks, and the arrow symbols on the clamps corresponding to the source-to-load directions of the circuit.

• Do not use a clamp-on current probe with any non-insulated conductor.

● Check Items

The following items are checked and judged, and then the result of each check item will be displayed as shown on the next page.

For each voltage input: For each current input:

1. Existence of input voltages 1. Existence of input currents

2. Frequency detection 2. Clamp directions

3. Voltage phase sequence

NOTE

•Measurement is not performed during the wiring check.

• The wiring check cannot be carried out during continuous measurement.

5-6

IM CW120-E

● Check Items and Criteria

Voltage Inputs

5.5 Wiring Check Function

Item

1. Existence of voltage inputs

2. Frequency detection

3. Voltage phase sequence

Item

1. Existence of input currents

2. Clamp directions

Criteria

• If an input level is 10% or less of the range, then an error results.

• Else, the frequency detection takes place.

• If the frequency of input V1 exceeds the 40 to

70 Hz range, then an error results.

• Else, the voltage phase sequence check takes place.

For 1∅2W or 1∅3W:

• This item is not checked. For 3∅3W:

• If V2 leads V1 by more than approximately 80 degrees or less than approximately 40 degrees, an error results.

For 3∅4W (only for the CW121):

• If V2 lags behind V1 by more than approximately 140 degrees or less than approximately 100 degrees, an error results.

• Or if V3 leads V1 by more than approximately 140 degrees or less than approximately 100 degrees, an error results.

• Else, “Good” is displayed.

Current Inputs

Criteria

• If an input level is 1% or less of the range, then an error results.

• Else, the clamp direction check takes place.

• For any wiring method other than 3∅3W, if the

power of one or more phases is negative, an error results.

• For 3∅3W, if the whole power is negative, an error results.

• Else, “Good” is displayed.

Error Message

(in lower row)

Error message

Error Message

(in lower row)

Error message

Wiring

NOTE

• As the wiring is judged on the above criteria, an error may result even when wiring is correct or wrong wiring may pass the check.

•When a measured value appears to be abnormal, check the above criteria and wiring again.

IM CW120-E

5-7

5.5 Wiring Check Function

● Carrying out Wiring Check

(1) When the measurement screen is displayed, press the key for at

least three seconds, and “ ” appears on the screen and flashes.

START

&STOP

(2) Press the key. Then, “ ” stops flashing and the wiring check

begins.

WIRING

Press WIRING key for at least three seconds.

START&STOP key

(3) When no error has been found, “ ” is displayed on both the upper

and lower rows. Press the key to return to the measurement screen.

When no error

Upper: Judgment of current inputs

Lower: Judgment of voltage inputs

WIRING

WIRING key

START

&STOP

START&STOP key

5-8

IM CW120-E

5.5 Wiring Check Function

When an error is displayed, refer to the table on page 5-8 and check the meaning of the error. Check and correct the connections, then press the key to carry out the wiring check again.

To return to the measurement screen, press the

Example of error indications

Upper: No current input

Lower: Voltage phase sequence error ( when frequency error)

WIRING

WIRING key

START

&STOP

START&STOP key

key.

Wiring

IM CW120-E

5-9

Chapter 6. Setting Ranges and Wiring Method

6.1 Ranges and Display Digits

The following describes the voltage, current, power, and electric energy ranges.

● Voltage Range

150/300/450 V

● Current Range

96033 clamp-on probe: 5/10/20/50 A 96030 clamp-on probe: 20/50/100/200 A 96031 clamp-on probe: 50/100/200/500 A 96032 clamp-on probe: 200/500/1000 A

● Range of Active and Reactive Powers

The range of active and reactive powers is determined by the voltage range, current range, and wiring method set as follows:

Setting Ranges and Wiring Method

Wiring Method (Phase Lines)

Single-phase two wires Single-phase tow-wires × 2 Single-phase tow-wires × 3*

Single-phase three wires Three-phase three wires

Three-phase four wires*

*Only for CW121

Power Range

Voltage range × current range

Voltage range × current range × 2

Voltage range × current range × 3

IM CW120-E

6-1

6.1 Ranges and Display Digits

● Range Table (Table of Full Scales) – Rated Power

The table below shows the rated powers corresponding to combinations of voltage and current ranges.

Voltage

(V)

Range

150 V

300 V

450 V

* Only for CW121

Phase Lines

1∅2W 1∅2W ×2 1∅2W ×3* 1∅3W 3∅3W 3∅4W* 1∅2W 1∅2W ×2 1∅2W ×3* 1∅3W 3∅3W 3∅4W* 1∅2W 1∅2W ×2 1∅2W ×3* 1∅3W 3∅3W 3∅4W*

96033 Probe (5–50 A)

5.000 A

750.0 W

1.500 kW

2.250 kW

1.500 kW

3.000 kW

4.500 kW

2.250 kW

4.500 kW

6.750 kW

10.00 A

1.500 kW

3.000 kW

4.500 kW

3.000 kW

6.000 kW

9.000 kW

4.500 kW

9.000 kW

13.50 kW

Current (A) Range

96031 Probe (50–500 A)

96030 Probe (20–200 A)

20.00 A

3.000 kW

6.000 kW

9.000 kW

6.000 kW

12.00 kW

18.00 kW

9.000 kW

18.00 kW

27.00 kW

50.00 A

7.500 kW

15.00 kW

22.50 kW

15.00 kW

30.00 kW

45.00 kW

22.50 kW

45.00 kW

67.50 kW

100.0 A

15.00 kW

30.00 kW

45.00 kW

30.00 kW

60.00 kW

90.00 kW

45.00 kW

90.00 kW

135.0 kW

96032 Probe (200–1000 A)

200.0 A

30.00 kW

60.00 kW

90.00 kW

60.00 kW

120.0 kW

180.0 kW

90.00 kW

180.0 kW

270.0 kW

500.0 A

75.00 kW

150.0 kW

225.0 kW

150.0 kW

300.0 kW

450.0 kW

225.0 kW

450.0 kW

675.0 kW

1.000 kA

150.0 kW

300.0 kW

450.0 kW

300.0 kW

600.0 kW

900.0 kW

450.0 kW

900.0 kW

1.350 MW

TIP

For reactive power, the same table applies but the units of measurement are different.

Units of reactive power: Var, kVar, MVar

If either or both of the VT and CT ratios are set to a value other than 1, and if the product of the following formula exceeds 9999, the decimal point is incremented by one:

Rated power in table × VT ratio × CT ratio × 1.3

6-2

IM CW120-E

6.1 Ranges and Display Digits

Range × VT Ratio (× 1.3)*

150

100

to 999.9 to 9.999 to 99.99 to 999.9 to 4.5

V kV kV kV MV

Decimal Point Position and Unit

999.9

9.999

99.99

999.9

4.500

V kV kV kV MV

Decimal Point Position and Unit

9.999

99.99

999.9

9.999

99.99

999.9

9.999

10.00

Range × CT Ratio (× 1.3)*

100

to 9.999 to 99.99 to 999.9 to 9.999 to 99.99 to 999.9 to 9.999 10

A A A kA kA kA MA MA

Decimal Point Position and Unit

70.00

Input Frequency

40 to 70 Hz

Rated Power × VT Ratio × CT Ratio (× 1.3)*

to 999.9 to 9.999 to 99.99 to 999.9 to 9.999 to 99.99 to 999.9 to 9.999 to 99.99 to 999.9 to 9.999 to 99.99 to 999.9

to 9999

W W W W kW kW kW MW MW MW GW GW GW GW

Decimal Point Position and Unit

999.9

9.999

99.99

999.9

9.999

99.99

999.9

9.999

99.99

999.9

9.999

99.99

999.9 9999

W W W W kW kW kW MW MW MW GW GW GW GW

975

100

1000

* Multiply by 1.3 only when the CT or VT ratio is a value other than 1.

● Display Digits

The tables below show the display digits, decimal point positions, and units of measurement.

Voltage – Maximum Display Digits: 4

Current – Maximum Display Digits: 4

Frequency – Maximum Display Digits: 4

Power – Maximum Display Digits: 4

Setting Ranges and Wiring Method

IM CW120-E

6-3

Power Factor

–1 to 1

Decimal Point Position and Unit

1.000

6.1 Ranges and Display Digits

TIP

For reactive power, the same table as for the power applies but the units of measurement are different.

Units of reactive power: Var, kVar, MVar, GVar

Power Factor – Maximum Display Digits: 4

● Decimal Point Position and Unit for Electric Energy

The decimal point position and unit of measurement for electric energy can be set via the screen (see Section 7.2.17, “Selecting Decimal Point Position and Unit for Electric Energy”).

• Decimal point: Selectable from 000.000, 0000.00, 00000.0, and 000000

•Unit: Selectable from Wh, kWh, MWh, and GWh

By selecting STANDARD, you can also let the CW120/121 automatically set them as follows.

Rated Power × VT Ratio × CT Ratio (× 1.3)*

1 to 9.999

10 to 99.99

100 to 999.9

1 to 9.999

10 to 99.99

100 to 999.9

1 to 9.999

10 to 99.99

100 to 999.9

1 to 9.999

10 to 99.99

100 to 999.9

* Multiply by 1.3 only when the CT or VT ratio is a value other than 1.

W W W kW kW kW MW MW MW GW GW GW

Decimal Point Position and Unit for Electric energy

(Max. Count)

0.00

0.0

0.000

0.00

0.0

0.000

0.00

0.0

0.000

0.00

0.0 0

to 9999.99 to 99999.9 to 999.999 to 9999.99 to 99999.9 to 999.999 to 9999.99 to 99999.9 to 999.999 to 9999.99 to 99999.9 to 999999

Wh Wh kWh kWh kWh MWh MWh MWh GWh GWh GWh GWh

SEE ALSO

For the setting procedures, see Chapter 7, “Making Settings.”

6-4

IM CW120-E

6.1 Ranges and Display Digits

When the electric energy count has reached the maximum, the count will be reset to zero as illustrated below.

999.999 kWh

Power

Time

WARNING

When newly starting integrating power, clear the electric energy count (and the elapsed time of integration). Otherwise, the electric energy count will be added to the previous value. For details of how to clear the electric energy count, see Section 9.2.3, “Clearing Electric Energy Count,” or Section 7.2.4, “Clearing Electric Energy Count and Resetting System,” in Chapter 7, “Making Settings.”

Setting Ranges and Wiring Method

IM CW120-E

6-5

6.2 Changing Voltage Range Setting

● Procedure to Change Voltage Range Setting

(1) The sign is displayed uppermost on the screen, under the voltage

range currently selected. To change the range, press the key when the measurement screen is displayed.

150V 300V 450V

RANGE

Voltage ranges

V RANGE key

Each press of the key changes the range selection sequentially as follows:

150 V 300 V 450 V

Default: 150 V

TIP

• If a change to the range setting is incompatible with the conditions derived from other settings, is displayed and the change is ineffective. First change other settings such as the current range, VT ratio, CT ratio, and wiring method, then change the voltage range.

• The voltage range cannot be changed during continuous measurement.

• The voltage range cannot be changed when the electric energy count is not zero. Pressing the key at this time causes to appear on the screen (this will disappear and the measurement screen will return when any key is pressed). Clear the electric energy count first. For details of how to do this, see Section 9.2.3, “Clearing Electric Energy Count,” or Section 7.2.4, “Clearing Electric Energy Count and Resetting System,” in Chapter 7, “Making Settings.”

6-6

IM CW120-E

6.3 Changing Current Range Setting

● Procedure to Change Current Range Setting

(1) The sign is displayed lowermost on the screen, above the current

range currently selected. To change the range, press the key when the measurement screen is displayed.

Setting Ranges and Wiring Method

5A 10A 20A 50A 100A 200A 500A 1000A

RANGE

Current ranges

A RANGE key

Each press of the key changes the range selection sequentially as follows:

When the 96030 clamp-on probe is selected for use

20 A 50 A 100 A 200 A

Default: 20 A

TIP

• The voltage range cannot be changed during continuous measurement.

IM CW120-E

6-7

6.3 Changing Current Range Setting

When the 96033 clamp-on probe is selected for use

5 A 10 A 20 A 50 A

Default: 5 A

When the 96031 clamp-on probe is selected for use

50 A 100 A 200 A 500 A

Default: 50 A

When the 96032 clamp-on probe is selected for use

200 A 500 A 1000 A

Default: 200 A

● Selecting Clamp-on Current Probe to Be Used

The current ranges that can be selected vary with the clamp-on current probe used. The probe selection can be changed from a setting screen.

Clamp-on Current Probe Models and Ratings

Clamp-on Current Probe Model

96033 96030 96031 96032

Default: 200 A

Setting

50 A 200 A 500 A

1000 A

Rating (Ranges)

5/10/20/50 A 20/50/100/200 A 50/100/200/500 A 200/500/1000 A

Procedure to Change Probe Selection

(1) Press the key when the measurement screen is displayed. The

screen switches to the setting item selection screen and the sign appears in the lower left of the screen.

(2) Using the keys, make the mark (in the lower right) and its

current setting appear on the screen. Then, press the key. The number representing the currently selected clamp model flashes.

6-8

IM CW120-E

6.3 Changing Current Range Setting

MEAS/SET key

MEAS/SET

ENTER

DISP

UP/DOWN/LEFT/RIGHT keys

ENTER key

(3)Using the keys, select the number corresponding to the

desired clamp-on current probe.

or or

(4) Press the key.

(5) Press the key to return to the measurement screen. The range is

changed according to the new probe selected.

SEE ALSO

For details of the clamp selection, see Chapter 7, “Making Settings.”

TIP

• If a change to the clamp-on current probe selection is incompatible with the conditions derived from other settings, the change is ineffective. First change other settings such as the voltage range, VT ratio, CT ratio, and wiring method, then change the probe selection.

• The current probe cannot be changed during continuous measurement.

• The current probe cannot be changed when the electric energy count is not zero, and an attempt to change causes to appear on the screen (this will disappear and the measurement screen will return when any key is pressed). Clear the electric energy count first. For details of how to do this, see Section 9.2.3, “Clearing Electric Energy Count,” or Section 7.2.4, “Clearing Electric Energy Count and Resetting System,” in Chapter 7, “Making Settings.”

Setting Ranges and Wiring Method

IM CW120-E

6-9

6.4 Changing Wiring Method Setting

● Procedure to Change Wiring Method Setting

(1) The sign is displayed uppermost on the screen, above the wiring

method currently selected. To change the method, press the key when the measurement screen is displayed.

Wiring methods

WIRING

WIRING key

Each press of the key changes the wiring method selection sequentially as follows:

For CW120

1∅2W 1∅3W 3∅3W

Default: 3∅3W

TIP

• If a change to the wiring method setting is incompatible with the conditions derived from other settings, the change is ineffective . First change other settings such as the voltage range, current range, VT ratio, and CT ratio, then change the wiring method.

• The wiring method cannot be changed during continuous measurement.

• The wiring method cannot be changed when the electric energy count is not zero. Pressing the key at this time causes to appear on the screen (this will disappear and the measurement screen will return when any key is pressed). Clear the electric energy count first. For details of how to do this, see Section 9.2.3, “Clearing Electric Energy Count,” or Section 7.2.4, “Clearing Electric Energy Count and Resetting System,” in Chapter 7, “Making Settings.”

1∅2W ×2

6-10

IM CW120-E

For CW121

6.4 Changing Wiring Method Setting

1∅2W 1∅3W 3∅3W

Default: 3∅3W

SEE ALSO

For details of the wiring methods, see Chapter 5, “Wiring.”

Indication of wiring method.

<1∅2W ×2> CW120

<1∅2W ×3> CW121

3∅4W

CW121

1∅2W ×21∅2W ×3

Setting Ranges and Wiring Method

IM CW120-E

6-11

Chapter 7. Making Settings

7.1 Setting Items and Item Selection

● Setting Items

Before starting measurement, the following measurement condition and data saving settings should be made as necessary.

Setting Item Display Mark

1. Device number

2. Loading and saving of settings

3. Deletion of measured-data file and formatting of PC card

4. Clearance of electric energy count and resetting of system

5. Copying and clearance of backup memory

6. Date

7. Output interval

8. Integration start date and time

9. Integration stop date and time

10.Data saving to PC card

11.Communication device selection

12.Communication settings

13.Communication protocol setting

14.VT ratio setting

15.CT ratio setting

16.Clamp-on current probe selection

17.Decimal point position and unit selections for electric energy

Making Settings

TIP

The Setting Check Sheet in the back of their available selections. Use this sheet for grasping the setting conditions and for efficient setting on site.

IM CW120-E

Operation Guide

(IM CW120P-E) lists necessary settings and

7-1

7.1 Setting Items and Item Selection

● Keys Used for Setting

The keys used for setting are described below.

Device number

MEAS/SET key

UP/DOWN/LEFT/RIGHT keys

ENTER key

ESC

MEAS/SET

ENTER

DISP

ESC key

key Used to toggle the display between measurement and setting screens. The mark is displayed on a setting screen.

key

Used to fix a selection.

key

Used to cancel a setting. Pressing this key returns to the preceding screen.

keys

Used to:

• Change the setting item displayed.

• Change a number.

• Change a setting.

7-2

keys Used to:

• Change the setting item displayed.

• Select a digit.

• Change a setting.

IM CW120-E

7.1 Setting Items and Item Selection

● Setting Procedure

(1) Press the key. The display changes from the measurement screen

to the screen for setting (the setting item selection screen) and the sign appears in the lower left.

Device number setting screen

MEAS/SET key

UP/DOWN/LEFT/RIGHT keys

ENTER key

ESC

MEAS/SET

ENTER

DISP

Making Settings

ESC key

(2) Using the keys, select the desired item, and then press the

key. Each time one of the keys is pressed, the setting

item changes sequentially as follows.

or or

To cancel a setting after pressing the key, press the key. The setting item selection screen then returns.

(3) After making necessary changes to the settings, press the

key to

return to the measurement screen.

TIP

• The MEM (backup memory setting) is skipped if no data exists in the backup memory (and the MEM mark is not lit on the measurement screen).

• The DEV (communication device) setting is skipped if your CW120/121 model has an RS-485 interface.

• The setting item that is selected by default when the screen changes from the measurement screen, is the item selected last time the measurement screen was returned from a setting screen.

• In the electric energy measurement mode, the settings can be viewed only for checking and cannot be modified.

IM CW120-E

7-3

7.2 Setting Each Item

7.2.1 Setting Device Number ( )

Description

The device number is used for identifying each power meter (CW120/121) when monitoring a specific power with two or more CW120s and CW121s, and also used as the device address when using RS-485 communication.

The device number consists of three digits. It is set to 001 by default and can be set to any number from 001 to 999.

TIP

When using RS232 communication, in cases when the communication protocol is other than CW120/ 121 exclusive, Device number is used as the Device Address.

Communication protocols and device number limits

Communication Protocol Device number limits

CW120/121-dedicated communication Power monitor (PR201) communication PC link communication without checksum PC link communication with checksum MODBUS communication (ASCII mode) MODBUS communication (RTU mode)

1 to 999 1 to 31 1 to 99 1 to 99 1 to 247 1 to 247

Procedure

(1) Using the keys in the setting item selection screen, make the

mark and its corresponding setting appear on the screen. Then, press

the key. The rightmost digit begins flashing.

Device Number Setting Screen

MEAS/SET key

UP/DOWN/LEFT/RIGHT keys

ENTER key

ESC

MEAS/SET

ENTER

DISP

ESC key

7-4

IM CW120-E

7.2 Setting Each Item

(2) Using the keys, select the digit to be changed. The selected digit

flashes.

(3) Using the

keys, change the number of the selected digit.

(4) After making necessary changes, press the

number is then set and the setting item selection screen returns. To cancel the changes, press the

screen also returns.

7.2.2 Loading and Saving Settings ( )

Description

Select to load settings from a PC card. Select to save settings to a PC card.

The file number consists of three digits and can be set to any number from 000 to 029.

TIP

Name of setting file: WTH

nnn

.SET where

nnn

is the file number you set, from 000 to 029

Procedure

(1) Using the keys in the setting item selection screen, make the

mark to appear on the screen. Then, press the key.

begins flashing.

Loading/Saving Selection Screen

key. The new device

key. The setting item selection

Making Settings

IM CW120-E

MEAS/SET key

UP/DOWN/LEFT/RIGHT keys

ENTER key

ESC

MEAS/SET

ENTER

DISP

ESC key

(2) Using the keys, select or .

7-5

7.2 Setting Each Item

(3) Press the key to confirm the selection. A three-digit number

appears on the lower row, allowing you to set the file number of the file to/ from which you want to save/load settings.

To cancel loading/saving, press the

key. The setting item selection

screen returns.

File Number Setting Screen for Loading

MEAS/SET key

UP/DOWN/LEFT/RIGHT keys

ENTER key

ESC

MEAS/SET

ENTER

DISP

ESC key

(4) Specify the file number in accordance with the steps below.

7-6

(5) Using the

keys, select the digit to be changed. The selected digit

flashes. (6) Using the (7) After making necessary changes, press the

keys, change the number of the selected digit.

key. The settings are

then loaded and the setting item selection screen returns.

You cannot select the file number of a file that does not exist. Selecting

such a file number returns to the screen for file number setting.

To cancel loading, press the key. The screen in step (1) returns.

IM CW120-E

Saving

File Number Setting Screen for Saving

7.2 Setting Each Item

MEAS/SET key

UP/DOWN/LEFT/RIGHT keys

ENTER key

ESC

MEAS/SET

ENTER

DISP

ESC key

(4) Specify the file number in accordance with the steps below.

(5) The smallest file number within the unused numbers from 000 to 029 is

displayed. (6) If the displayed number is fine, press the key. (7) If you want to specify a different file number, using the

keys, select

the digit to be changed. The selected digit flashes. (8) Using the keys, change the number of the selected digit. (9) After making necessary changes, press the key. The settings are

then saved and the setting item selection screen returns.

You cannot select a file number that has already been used. Selecting

such a file number returns to the screen for file number setting.

To cancel saving, press the key. The screen in step (1) returns.

NOTE

•When the number of setting files residing in the inserted PC card has reached 30, you can no longer save the settings. Attempting to save settings causes to appear (this will disappear and the previous screen will return when any key is pressed). Delete an unnecessary file or files and try saving again.

• The loading cannot be performed when the electric energy count and the integration time are not zero. Attempting to load settings causes to appear on the screen (this will disappear and the measurement screen will return when any key is pressed). Clear the electric energy count first. For details of how to do this, see Section 9.2.3, “Clearing Electric Energy Count,” or Section 7.2.4, “Clearing Electric Energy Count and Resetting System,” in this chapter.

Making Settings

TIP

•When the PC card is full, the sign is displayed on the screen and the saving cannot be performed.

•Saving the settings when the communication device is set to a printer, prints the settings at the same time.

IM CW120-E

7-7

7.2 Setting Each Item

7.2.3 Deleting Measured-data Files and Formatting PC Card ( )

Description

Select to delete all the measured data saved in the PC card. Select to format the PC card.

Procedure

(1) Using the keys in the setting item selection screen, make the

mark to appear on the screen. Then, press the key.

begins flashing.

Measured-data Deletion Screen PC Card Formatting Screen

MEAS/SET key

UP/DOWN/LEFT/RIGHT keys

ENTER key

ESC

MEAS/SET

ENTER

DISP

ESC key

(2) Using the keys, select if you want to delete the

measured data or if you want to format the PC card.

(3) Press the

key. The selected action takes place and the setting item selection screen returns. To cancel the data deletion or formatting, press the key. The setting item selection screen also returns.

7-8

IM CW120-E

DISP

ENTER

MEAS/SET

ESC

MEAS/SET key

UP/DOWN/LEFT/RIGHT keys

ENTER key

ESC key

Electric Energy Count Clearance Screen System Resetting Screen

7.2 Setting Each Item

7.2.4 Clearing Electric Energy Count and Resetting System ( )

Description

Select to clear the electric energy count (watt-hours). Select to reset the system.

Clearing the electric energy count means to reset all of the electric energy count, elapsed time of integration, and regenerative energy count to zeros.

Resetting the system means to perform the same actions as clearing the electric energy count and initialize the settings to the defaults, except for the date, time, and device number.

Procedure

(1) Using the keys in the setting item selection screen, make the

mark to appear on the screen. Then, press the key.

begins flashing.

Making Settings

(2) Using the keys, select if you want to clear the electric

energy count or if you want to reset the system.

(3) Press the

key. The selected action takes place and the setting item selection screen returns. To cancel clearing the electric energy count or resetting the system, press the key. The setting item selection screen also returns.

NOTE

The electric energy count can also be cleared by simply pressing the key for three seconds or more in the measurement screen. For this, see Section 9.2.3, “Clearing Electric Energy Count.”

IM CW120-E

7-9

7.2 Setting Each Item

7.2.5 Copying and Clearing Backup Memory Contents ( )

Description

The CW120/121 have a memory for backing up the PC card. When the PC card becomes full or is removed, data is saved to the backup memory. For details, see Section 9.5, “Backup Memory.”

When no data resides in the backup memory, namely, when the

mark is not displayed on the measurement screen, this setting item cannot be called. Select to copy the data in the backup memory to the PC card. Select to delete the data from the backup memory.

Procedure

(1) Using the keys in the setting item selection screen, make the

mark to appear on the screen. Then, press the key.

appears and flashes.

Copy Screen Deletion Screen

MEAS/SET key

UP/DOWN/LEFT/RIGHT keys

ESC

MEAS/SET

ENTER

DISP

7-10

ENTER key

ESC key

(2) Using the keys, select if you want to copy the data in

the backup memory to the PC card or if you want to delete the data from the backup memory.

(3) Press the

key. The selected action takes place and the setting item selection screen returns. To cancel copying or deleting data, press the key. The setting item selection screen also returns.

IM CW120-E

7.2.6 Changing Date and Time ( )

Description

The CW120/121 have a clock, which is adjusted to the Japan standard time by default (factory setting). To change the date and time, follow the procedure below.

Procedure

(1) Using the keys in the setting item selection screen, make the

mark and the current data and time settings appear on the screen. Then, press the key. The day indication flashes.

Date and Time Change Screen

7.2 Setting Each Item

Year, month, and day

Hour:minute:second

MEAS/SET key

Making Settings

UP/DOWN/LEFT/RIGHT keys

ENTER key

ESC

MEAS/SET

ENTER

DISP

ESC key

(2) Using the keys, select an item — year, month, day, hour, minute, or

second — you want to change. The selected item flashes.

(3) Using the

keys, change the value of the selected item. When changing a number, pressing the key continuously will make quick changes.

(4) After making all necessary changes, press the

key. The date and time settings are changed and the setting item selection screen returns. To cancel the changes, press the key. The setting item selection screen also returns.

TIP

•For the year, set the last two digits. The range of the year setting is 00 to 99 (years 2000 to 2099).

•To make the changes effective, press the key synchronously with a time signal from a TV broadcast or the like.

IM CW120-E

7-11

7.2 Setting Each Item

7.2.7 Setting Output Interval ( )

Description

When saving (outputting) data in the electric energy measurement mode, the interval of saving (outputting) data needs to be set. This output interval is set to 30 minutes by default and can be selected from:

1, 2, 5, 10, 15, and 30 seconds, 1, 2, 5, 10, 15, and 30 minutes, and 1 hour.

Procedure

(1) Using the keys in the setting item selection screen, make the

mark and the current interval setting appear on the screen. Then,

press the key. The current setting flashes.

Output Interval Setting Screen

Interval

ESC

MEAS/SET

ENTER

MEAS/SET key

UP/DOWN/LEFT/RIGHT keys

DISP

ENTER key

ESC key

7-12

IM CW120-E

(30 min)

7.2 Setting Each Item

(2) Using the keys, select the desired interval. The displayed

interval time changes sequentially as follows.

or or

(1 hr) (1 sec) (2 sec) (5 sec)

(10 sec)

(15 min)

(15 sec)

(30 sec)(1 min)(2 min)(5 min)(10 min)

(3) After selecting the desired interval, press the key. The interval is

changed accordingly and the setting item selection screen returns. To cancel the change, press the key. The setting item selection screen also returns.

NOTE

When setting the output interval to 2 minutes or less, note the following.

• Depending on the number of files residing in the PC card and the free space in it, the data at the beginning may not be saved (for example, after approximately fifty-thousand samples have been saved at one-second intervals). If this occurs, appears on the screen and data saving is stopped.

• Especially when setting the interval to 1 second, make sure that:

There is no file in the PC card (format the PC card to delete all files). The PC card is inserted when starting the integration. Do not remove the PC card during electric energy measurement. Do not activate communication. Do not perform excessive key actions.

Only if data saving to the PC card is enabled (see Section 7.2.10), data is saved to the PC card at the specified interval.

Making Settings

IM CW120-E

7-13

7.2 Setting Each Item

7.2.8 Setting Integration Start Date and Time ( )

Description

There are three ways to start integration:

• Automatic starting at the specified time on the specified date

• Manual starting by pressing the

• Remote starting by inputting a signal at the external control terminals The following describes the start date and time setting for the first way.

Procedure

(1) Using the keys in the setting item selection screen, make the

mark and the current settings of the start date and time appear on the screen. Then, press the key. The day setting flashes.

Integration Start Date and Time Change Screen

key for one second or more

Year, month, and day

Hour:minute:second

MEAS/SET key

UP/DOWN/LEFT/RIGHT keys

ENTER key

ESC

MEAS/SET

ENTER

DISP

ESC key

(2) Using the keys, select an item — year, month, day, hour, minute, or

second — you want to change where the year, month, and day are shown with superscripts y, m, and d to avoid confusion. The selected item flashes.

(3) Using the

keys, change the value of the selected item. When changing a number, pressing the key continuously will make quick changes.

7-14

IM CW120-E

7.2 Setting Each Item

(4) After making all necessary changes, press the key. The start date

and time settings are changed and the setting item selection screen returns. To cancel the changes, press the key. The setting item selection screen also returns.

NOTE

Set a valid date and time.

• If the start date and time are set to before the current time, or if the specified start date and time has passed before a start after setting, integration will start at the appropriate time determined by the output interval.

• If the start date and time are set to the same as the stop date and time or to later than the stop date and time, the stop date and time are automatically set to the point after the output interval from the start date and time.

• Resetting the system changes the integration start date and time to the current time.

TIP

For the year, set the last two digits. The range of the year setting is 00 to 99 (years 2000 to 2099).

Making Settings

SEE ALSO

For details of the start and stop of integration, see Section 9.2, “Starting and Stopping Integration.”

IM CW120-E

7-15

7.2 Setting Each Item

7.2.9 Setting Integration Stop Date and Time ( )

Description

There are three ways to stop integration:

• Automatic stopping at the specified time on the specified date

• Manual stopping by pressing the

• Remote stopping by inputting a signal at the external control terminals The following describes the stop date and time setting for the first way.

Procedure

(1) Using the keys in the setting item selection screen, make the

mark and the current settings of the stop date and time appear on the

screen. Then, press the key. The day setting flashes.

Integration Stop Date and Time Change Screen

key for one second or more

Year, month, and day

Hour:minute:second

MEAS/SET key

UP/DOWN/LEFT/RIGHT keys

ENTER key

ESC

MEAS/SET

ENTER

DISP

ESC key

(2) Using the keys, select an item — year, month, day, hour, minute, or

second — you want to change where the year, month, and day are shown with superscripts y, m, and d to avoid confusion. The selected item flashes.

(3) Using the

keys, change the value of the selected item. When changing a number, pressing the key continuously will make quick changes.

(4) After making all necessary changes, press the

key. The stop date and time settings are changed and the setting item selection screen returns. To cancel the changes, press the key. The setting item selection screen also returns.

7-16

IM CW120-E

7.2 Setting Each Item

NOTE

Set a valid date and time.

•You cannot set the stop date and time to the same time or before the start date and time.

• Resetting the system changes the integration stop date and time to 30 minutes after the current time (since the output interval is initialized to the default, 30 minutes).

TIP

For the year, set the last two digits. The range of the year setting is 00 to 99 (years 2000 to 2099).

SEE ALSO

For details of the start and stop of integration, see Section 9.2, “Starting and Stopping Integration.”

Making Settings

IM CW120-E

7-17

7.2 Setting Each Item

7.2.10 Enabling/Disabling Data Saving to PC Card ( )

Description

This determines whether to save the measured data during electric energy measurement to the PC card. Select to enable (switch on) saving. Select to disable (switch off) saving. By default, the saving is enabled (switched on).

Procedure

(1) Using the keys in the setting item selection screen, make the

mark and the current on/off setting appear on the screen. Then, press the key. The setting flashes.

Not Saving Saving

MEAS/SET key

UP/DOWN/LEFT/RIGHT keys

ENTER key

ESC

MEAS/SET

ENTER

DISP

ESC key

(2) Using the keys, select if you want to enable saving

or if you want to disable saving.

(3) After making a change, press the

key. The change is made effective and the setting item selection screen returns. To cancel the change, press the key. The setting item selection screen also returns.

NOTE

• When the saving is enabled (on), data is saved to the PC card in the output interval set (in Section 7.2 7).

• When the saving is enabled (on), the mark is displayed also in the measurement screen.

7-18

IM CW120-E

7.2.11 Selecting Communication Device ( )

Description

For RS-232 communication, you can select the device to connect to. Select to connect to a personal computer. Select to connect to a printer. By default, connection to a personal computer is selected. For RS-485 communication, only connection to a personal computer is allowed, so this setting cannot be made.

Procedure

(1) Using the keys in the setting item selection screen, make the

mark and the current device selection appear on the screen. Then,

press the key. The selection flashes.

Selecting a Personal Computer Selecting a Printer

7.2 Setting Each Item

Making Settings

MEAS/SET key

UP/DOWN/LEFT/RIGHT keys

ENTER key

ESC

MEAS/SET

ENTER

DISP

ESC key

(2) Using the keys, select if you want to connect to a

personal computer or if you want to connect to a printer.

(3)After making a change, press the

key. The change is made effective and the setting item selection screen returns. To cancel the change, press the key. The setting item selection screen also returns.

NOTE

when a personal computer is selected, or when a printer is selected, flashes during

access to the corresponding device.

SEE ALSO

For the computer connection, see Chapter 11, “Communication Functions.” For the printer connection, see Section 12.2, “Using Optional Printer.”

IM CW120-E

7-19

7.2 Setting Each Item

7.2.12 Making Communication Settings ( )

Description

Follow the procedure below to set the baud rate, data bits, parity bit, and stop bits to match the specifications of the device to connect to.

• Baud rate: 1200, 2400, 4800, 9600,19200 or 38400 bps (9600 bps by default)

• Data bits: 7 or 8 (8 bits by default)

• Parity: for no parity (default)

for even parity for odd parity

• Stop bits: 1 or 2 (1 bit by default)

Procedure

(1) Using the keys in the setting item selection screen, make the

mark and the current communication settings appear on the screen. Then, press the key. The baud rate setting flashes.

Communication Setting Screen

Baud rate

Data bits-parity-stop bits

MEAS/SET key

UP/DOWN/LEFT/RIGHT keys

ENTER key

ESC

MEAS/SET

ENTER

DISP

ESC key

(2) If necessary, change the baud rate using the keys. The baud rate

changes sequentially as follows.

7-20

IM CW120-E

7.2 Setting Each Item

(3) Press the key to move to the data bit setting. The leftmost number in

the lower row flashes. If necessary, change the data bit setting using the

keys.

(4) Press the

the lower row flashes. If necessary, change the parity bit setting using the

(5) Press the

the lower row flashes. If necessary, change the stop bit setting using the

(6) After making all necessary changes, press the

are changed accordingly and the setting item selection screen returns. To cancel the changes, press the key. The setting item selection screen also returns.

TIP

• You can move between the baud rate, data bit, parity bit, and stop bit settings from one to another in the reverse direction by using the key.

• Resetting the system using a command via communication leaves the baud rate, data bit, parity bit, and stop bit settings unchanged.

key to move to the parity bit setting. The middle number in

keys.

key to move to the stop bit setting. The rightmost number in

keys.

key. The settings

Making Settings

IM CW120-E

7-21

7.2 Setting Each Item

7.2.13 Setting Communication Protocol ( )

Description

CW120/121 can configure the following 6 communication protocols.

Communication Protocols

Communication Protocol Explanation

CW120/121-dedicated communication Power monitor (PR201) communication PC link communication without sum check PC link communication with sum check MODBUS communication (ASCII mode) MODBUS communication (RTC mode)

Default: CW120/121-dedicated communication

Procedure

(1) Using the keys in the setting item selection screen, make the

. and the existing communication protocol setting appear on the screen. Then, press the key. The communication protocol setting flashes.

Communication Protocol Setting Screen

CW120/121-dedicated communication standard Communication standard used for power monitor Without error check With error check Communication using ASCII data Communication using Binary data

Communication protocol

MEAS/SET key

UP/DOWN/LEFT/RIGHT keys

ENTER key

ESC

MEAS/SET

ENTER

DISP

ESC key

(2) Using the keys, select the communication protocol. The

displayed communication protocol changes sequentially as follows.

or or

(3) After selecting the communication protocol, press the key. The

communication protocol is changed accordingly and the setting item selection screen returns. To cancel the change, press the key, The setting item selection screen also returns.

SEE ALSO

For details of the communication function, see the CW120/121 CLAMP-ON POWER METERS Communication Functions user’s manual (IM CW120C-E).

7-22

IM CW120-E

7.2.14 Setting VT Ratio ( )

Description

When installing an external voltage transformer (VT) and inputting the secondary-circuit output of the VT to the CW120/121, setting the VT ratio appropriately will display the reading correctly in the scale of the primary circuit, namely, will perform scaling.

The VT ratio can be set from 1 to 10000 and is set to 1 by default. When not using a VT, set the VT ratio to 1.

7.2 Setting Each Item

Whenever the VT ratio is set to a value other than 1, the

mark is displayed

even in the measurement mode.

Procedure

(1) Using the keys in the setting item selection screen, make the

mark and the existing VT ratio setting appear on the screen. Then,

press the key. The digit of the one place flashes.

VT Ratio = 1 VT Ratio = 10000

MEAS/SET key

UP/DOWN/LEFT/RIGHT keys

ENTER key

ESC

MEAS/SET

ENTER

DISP

Making Settings

IM CW120-E

ESC key

(2) Using the keys, select the digit to be changed. The selected digit

flashes. (3) Using the (4) After making necessary changes, press the

keys, change the number.

key. The VT ratio setting is changed accordingly and the setting item selection screen returns. To cancel the changes, press the key. The setting item selection screen also returns.

7-23

7.2 Setting Each Item

NOTE

• The VT ratio cannot be changed when the electric energy count or the elapsed time of integration is not zero. Attempting to change the ratio causes to appear on the screen (this will disappear and the measurement screen will return when any key is pressed). Clear the electric energy count first. For details of how to do this, see Section 9.2.3, “Clearing Electric Energy Count,” or Section 7.2.4, “Clearing Electric Energy Count and Resetting System,” in this chapter.

•A setting that causes the product of [VT ratio × CT ratio × rated power × 1.3] to exceed 9999 GW is not allowed.

TIP

Example of VT ratio setting:

When using a 2200-to-110 V transformer, the transformer ratio is 20:1. So, set the VT ratio to 20.

Displayed values:

Range of voltage reading: Voltage range × VT ratio Range of current reading: Current range × CT ratio Range of power reading: Rated power × VT ratio × CT ratio

7-24

IM CW120-E

7.2.15 Setting CT Ratio ( )

Description

When installing an external current transformer (CT) and inputting the secondary-circuit output of the CT to the CW120/121, setting the CT ratio appropriately will display the reading correctly in the scale of the primary circuit, namely, will perform scaling.

The CT ratio can be set from 1.00 to 10000.0 and is set to 1.00 by default. When not using a CT, set the CT ratio to 1.00.

7.2 Setting Each Item

Whenever the CT ratio is set to a value other than 1.00, the

mark is

displayed even in the measurement mode.

Procedure

(1) Using the keys in the setting item selection screen, make the

mark and the existing CT ratio setting appear on the screen. Then,

press the key. The digit of the one place flashes.

CT Ratio = 1.00 CT Ratio = 10000.0

MEAS/SET key

UP/DOWN/LEFT/RIGHT keys

ENTER key

ESC

MEAS/SET

ENTER

DISP

Making Settings

IM CW120-E

ESC key

(2) Using the keys, select the digit to be changed. The selected digit

flashes. (3) Using the (4) After making necessary changes, press the

keys, change the number.

key. The CT ratio setting is changed accordingly and the setting item selection screen returns. To cancel the changes, press the key. The setting item selection screen also returns.

7-25

7.2 Setting Each Item

NOTE

• The CT ratio cannot be changed when the electric energy count or the elapsed time of integration is not zero. Attempting to change the ratio causes to appear on the screen (this will disappear and the measurement screen will return when any key is pressed). Clear the electric energy count first. For details of how to do this, see Section 9.2.3, “Clearing Electric Energy Count,” or Section 7.2.4, “Clearing Electric Energy Count and Resetting System,” in this chapter.

•A setting that causes the product of [VT ratio × CT ratio × rated power × 1.3] to exceed 9999 GW is not allowed.

TIP

Example of CT ratio setting:

When using a 100-to-5 A transformer, the transformer ratio is 20:1. So, set the CT ratio to 20.

Displayed values:

Range of voltage reading: Voltage range × VT ratio Range of current reading: Current range × CT ratio Range of power reading: Rated power × VT ratio × CT ratio

7-26

IM CW120-E

7.2.16 Selecting Clamp-on Current Probe to Be Used ( )

Description

The following four models of clamp-on current probes can be connected to the CW120/121.

Selectable Clamp-on Current Probes

7.2 Setting Each Item

Clamp-on Current Probe Model

96033 96030 96031 96032

Default: 200 A

Setting

50 A 200 A 500 A

1000 A

Rating (Ranges)

5/10/20/50 A 2/50/100/200 A 50/100/200/500 A 200/500/1000 A

Procedure

(1) Using the keys, make the mark (in the lower right) and its

current setting appear on the screen. Then, press the key. The number representing the currently selected clamp model flashes.

Selecting Clamp-on Current Probe to Be Used

MEAS/SET key

Making Settings

IM CW120-E

UP/DOWN/LEFT/RIGHT keys

ENTER key

ESC

MEAS/SET

ENTER

DISP

ESC key

(2)Using the keys, select the number corresponding to the

desired clamp-on current probe. The number changes sequentially as follows.

or or

7-27

7.2 Setting Each Item

(3) After selecting the desired number, press the key. The probe

selection is changed accordingly and the setting item selection screen returns. To cancel the change, press the key. The setting item selection screen also returns.

NOTE

The clamp-on current probe selection cannot be changed when the electric energy count or the integration time is not zero. Attempting to change the selection causes to appear on the screen (this will disappear and the measurement screen will return when any key is pressed). Clear the electric energy count first. For details of how to do this, see Section 9.2.3, “Clearing Electric Energy Count,” or Section 7.2.4, “Clearing Electric Energy Count and Resetting System,” in this chapter.

TIP

A maximum of three clamp-on current probes may be connected though it varies with the wiring method; probes having different ratings cannot be used at the same time. Namely, the clamp-on probes used at the same time must be of the same model.

7-28

IM CW120-E

7.2 Setting Each Item

7.2.17 Setting Decimal Point Position and Unit of Electric Energy ( )

Description

You can set the decimal point position and unit of the electric energy readings.

Select

(default) when using the standard settings. Selecting the standard setting lets the CW120/121 power meter determine the decimal point position and unit based on the product of [rated power × VT ratio × CT ratio × 1.3] as follows.

Rated Power × VT Ratio × CT Ratio × 1.3 Decimal Point Position and Unit

1 to 9.999

10 to 99.99

100 to 999.9

1 to 9.999

10 to 99.99

100 to 999.9

1 to 9.999

10 to 99.99

100 to 999.9

1 to 9.999

10 to 99.99

100 to 999.9

W W W kW kW kW MW MW MW GW GW GW

0.00

0.0

0.000

0.00

0.0

0.000

0.00

0.0

0.000

0.00

0.0 0

to 9999.99 to 99999.9 to 999.999 to 9999.99 to 99999.9 to 999.999 to 9999.99 to 99999.9 to 999.999 to 9999.99 to 99999.9 to 999999

Wh Wh kWh kWh kWh MWh MWh MWh GWh GWh GWh GWh

When specifying the desired decimal point position and unit, select:

• Decimal position setting from 000.000, 0000.00, 00000.0, and 000000.

• Unit from Wh, kWh, MWh, and GWh.

Procedure

(1) Using the keys, make the mark and its current settings

appear on the screen. Then, press the key. or the number representing the currently set decimal point position flashes.

Making Settings

IM CW120-E

7-29

7.2 Setting Each Item

When Setting Neither Decimal Point Position Nor Unit Specifically

When Using Standard Settings

Representing “standard”

MEAS/SET key

UP/DOWN/LEFT/RIGHT keys

ESC

MEAS/SET

ENTER

DISP

ENTER key

ESC key

(1) Using the keys, select . (2) Then, press the

key. The settings are changed accordingly and the setting item selection screen returns. To cancel the change, press the key. The setting item selection screen also returns.

7-30

IM CW120-E

When Setting Decimal Point Position Specifically

Setting Decimal Point Position

Move the decimal point using the UP/DOWN/LEFT/RIGHT keys.

MEAS/SET key

7.2 Setting Each Item

UP/DOWN/LEFT/RIGHT keys

ENTER key

ESC

MEAS/SET

ENTER

ESC key

DISP

(1)Using the keys, move the decimal point to the desired

position.

(2) Then, press the

key. The setting is changed accordingly and the unit setting begins flashing. To cancel the change, press the key. The setting item selection screen also returns.

The decimal point moves sequentially by the

keys as shown

below.

or or

Making Settings

IM CW120-E

7-31

7.2 Setting Each Item

When Setting Unit Specifically

(1) After finishing changing the decimal point position setting, the unit setting

starts flashing to allow you to change it.

Setting Unit

Select the unit from Wh, kWh, MWh, and GWh using the UP/DOWN/LEFT/RIGHT keys.

MEAS/SET key

UP/DOWN/LEFT/RIGHT keys

ENTER key

ESC

MEAS/SET

ENTER

ESC key

DISP

(2) Using the keys, change the unit. (3) Then, press the

key. The setting is changed accordingly and the setting item selection screen returns. To cancel the change, press the key. The setting item selection screen also returns.

7-32

IM CW120-E

7.3 Setting Name of Measured-data File

When saving the measured data in the electric energy measurement mode, you can set the name of the file to which measured data is to be saved.

File name = xxxxxxxx.CSV

Name (xxxxxxxx): Eight or less characters Filename extension: Always CSV

Command: INTEgrate:STORe:FILEname

When the file name is set, the set file name is displayed on the power meter’s screen (called by pressing the key) as shown below.

Filename

NOTE

•Once the file name is set, it remains the same even though integration is repeatedly perf ormed, namely, the measured data will be added to the same file.

•To reset the file name setting, reset the system or set the file name to ””.

• If the file name is not set, it will be assigned automatically.

SEE ALSO

For details of communication, see Chapter 11, “Communication Functions” and Chapter 12, “Communication Commands.”

Making Settings

IM CW120-E

7-33

Chapter 8. Instantaneous Value Measurement

8.1 Measuring Instantaneous Values

The CW120/121 power meters have two modes for measurement:

1. Instantaneous value measurement: Measures the rms voltages and rms current of individual phases, and power, reactive power, power factor, and frequency.

2. Electric energy measurement: In addition to the values in the instantaneous value measurement mode, measures the electric energy. Measurement is performed continuously and integration is started and stopped by using the keys.

This section describes instantaneous value measurement.

● Displayed Data

Item

Rms voltage

Rms current

Active power

Reactive power Power factor

Frequency Active electric energy

(watt-hours)

Elapsed time of integration

Unit

Var

—

Hour: minute:second

Hour: minute

Hour

V1, V2, V3 (differs depending on the wiring method).

A1, A2, A3 (differs depending on the wiring method).

W, W1, W2, W3 (differs depending on the wiring method).

Var, Var1, Var2, V ar3 (differs depending on the wiring method).

PF, PF1, PF2, PF3 Hz (input frequency of V1)

Wh, Wh1, Wh2, Wh3 00:00:00TIME

0000:00TIME 00000hTIME

The display format changes over between the above automatically depending on the elapsed time.

Displayed Name

Instantaneous Value Measurement

IM CW120-E

● Measurement Procedure

1. Perform safety checks

with reference to Chapter 3, “Precautions for Safe Measurement.”

2. Turn on the power to CW120/121

with reference to Chapter 4, “Connecting Power Supply and Turning Power On/Off.”

3. Perform wiring

with reference to Chapter 5, “Wiring.”

4. Set the ranges and wiring method

with reference to Chapter 6, “Setting Ranges and Wiring Method.”

5. Set measurement conditions

with reference to Chapter 7, “Making Settings.”

6. Measure instantaneous values.

8-1

8.2 Switching Display Contents

Pressing one of the UP/DOWN/LEFT/RIGHT keys changes the display contents in order. The sequence differs depending on the wiring method set. For example, the sequence when the single-phase two-wire method is chosen is shown below. Even for the unseen data items, the respective calculations are performed internally.

Sequence of Display Contents Switching for Single-phase Two Wires

Measurement Screen

Using UP/DOWN/LEFT/RIGHT keys

Upper: Rms voltage

Lower: Rms current

Measurement Screen

Upper: Active power

Lower: Reactive power

Upper: Power factor

Lower: Frequency

Upper: Active electric energy

8-2

Lower: Elapsed time of integration

IM CW120-E

● Differences in Display Contents Depending on Wiring Method

Display contents differ depending on the wiring method as follows:

Phase Wires

Single-phase two wires (1∅2W) Single-phase three wires (1∅3W)

Three-phase three wires (3∅3W) Three-phase four wires (3∅4W)

Single-phase tow-wires ×2 (1∅2W ×2)

Single-phase tow-wires ×3 (1∅2W ×3)

Display Position

Upper row Lower row Upper row Lower row Upper row Lower row

Upper row

Lower row

Upper row

Lower row

Screen

V1 A1 V1 V2 V1 V2

V1 A1

A1 A2 A3

8.2 Switching Display Contents

Displayed Item

Screen

Var

A1 A2 V3

A1 W1 W2

Var1 Var2

W1 W2 W3

Var1 Var2 Var3

Screen

PF Hz

Var

A3 PF1 PF2

Hz PF1

PF2 PF3

Screen

TIME

PF Hz

Var Wh1 Wh2

TIME

Wh1 Wh2 Wh3

TIME

Screen

TIME

PF Hz

Screen

TIME

Instantaneous Value Measurement

Name/Unit Appearing Next to Each Value

V1, V2, V3: Input rms voltages A1, A2, A3: Input rms currents corresponding to CH1, CH2, and

CH3, respectively

W, W1, W2, W3: Active power (with minus sign in case of negative

value)

Var, Var1, Var2, Var3: Reactive power (with minus sign in case of negative

value)

PF, PF1, PF2, PF3: Power factor (with minus sign in case of negative

value) Hz: Frequency Wh, Wh1, Wh2, Wh3: Active electric energy TIME: Elapsed time of integration

3∅4W

1∅3W or 3∅3W

1∅2W

Screen 1 Screen 2 Screen 3 Screen 4 Screen 5 Screen 6

IM CW120-E

8-3

8.2 Switching Display Contents

1∅2W ×3

1∅2W ×2

Screen 1(Load1)

V1 A1

Screen 2(Load1)

Var1

Screen 3(Load1)

PF1

Screen 4(Load1)

Wh1

TIME

Screen 1(Load2)

Screen 2(Load2)

Var2

Screen 3(Load2)

PF2

Screen 4(Load2)

Wh2

TIME

Screen 1(Load3)

V1 A3

Screen 2(Load3)

Var3

Screen 3(Load3)

PF3

Screen 4(Load3)

Wh3 TIME

TIP

• The active electric energy and elapsed time of integration are displayed also during instantaneous value measurement.

• Polarities of Active Power, Reactive Power and Power Facter

8-4

Phase difference Active Power Reactive Power Power Factor

Lag

180 180









Lead 90







IM CW120-E

8.3 Saving Data

There are two ways to save measured data to the PC card:

1. Manual, on-demand saving by pressing the instantaneous value measurement

2. Auto-saving at the preset output interval during electric energy measurement (continuous measurement)

This section describes the former way.

Procedure

Pressing the key when the measurement screen is displayed during instantaneous value measurement causes a one-shot action of saving all the measured values. (This action is referred to as manual saving.)

(1)When the measurement screen is displayed, press the

number then appears on the screen and all the measured values are saved.

File Number Display upon Manual Saving

Saving-to-PC-card mark

key during

key. The file

Instantaneous Value Measurement

IM CW120-E

Data record number File number

SAVE key

SAVE

(2) Pressing the key again saves the measured values again with the

data record number incremented but with the file number unchanged.

8-5

8.3 Saving Data

NOTE

• The file name will be given automatically.

• The file number is renewed in the following cases: (1) the data record number has exceeded 99; (2) the wiring method has changed; (3) the or actions have been carried out in the setting screen; (4) the PC card is removed or a PC card is inserted; and (5) the power is turned off once and then back on.

• Up to 30 files can be saved to a PC card (corresponding to file numbers from 000 to 029); attempting to save too many files causes to appear. This will disappear and the measurement screen will return when any key is pressed. Delete an unnecessary file or files and try saving again.

• If there is something wrong with the inserted PC card, data cannot be saved and appears. (The measurement screen will return when any key is pressed.)

•When the PC card becomes full, the mark appears and data will not be saved.

•Saving the measured data when the communication device is set to a printer, causes the mark to flash and prints the data at the same time as the data saving.

File Name and Format

Measured data are saved to a CSV format file and the file name (“MWTH” followed by a number) is given automatically.

CW12x File Type Measure

Mode OUTPUT

DATE

2001/11/11 2001/11/11 2001/11/11

File name = MWTHxxx.CSV

Name (xxx): The smallest, unused number from 000 to 029 Filename extension: Always CSV

Example of Saved, Measured Data

Shown below is an example of a measured-data file (that was saved in a PC card) when opened from a spreadsheet application that has a CSV file converter. (The field configuration varies depending on the measurement conditions.)

2 1

OUTPUT TIME

10:10:00 10:15:00 10:21:00

INTEG START DATE

0000/00/00 0000/00/00 0000/00/00

INTEG START TIME

0:00:00 0:00:00 0:00:00

ELAPSED TIME

0:00:00 0:00:00 0:00:00

V1 I1 P Q PF F

Wh(+) Wh(–)

8-6

IM CW120-E

8.3 Saving Data

Header (measurement conditions)

CW12x:Indicates the model. File Type: “2” indicates a file containing instantaneous values

measured.

Measure Mode: “1” indicates electric energy measurement.

Fields of each data record

OUTPUT DATE: Date of output OUTPUT TIME:Time of output INTEG START DATE:Integration start date INTEG START TIME:Integration start time ELAPSED TIME:Elapsed time of integration

(The order of measured value fields below shows an example for the single-phase two-wire method.)

V1: Rms voltage (value appearing with “V1” on meter screen) I1: Rms current (value appearing with “A1” on meter screen) P: Active power (value appearing with “W” on meter screen) Q: Reactive power (value appearing with “Var” on meter screen) PF: Power factor (value appearing with “PF” on meter screen) F: Frequency (value appearing with “Hz” on meter screen) Wh(+):Active electric energy (value appearing with “Wh” on meter

screen)

Wh(–): Regenerative electric energy (not appearing on meter screen)

Instantaneous Value Measurement

SEE ALSO

For details, see Appendix 3, “File Structures and Data Items Printed.”

IM CW120-E

8-7

8.4 Frequency Measurement

The frequency of voltage input V1 is presented as the measured frequency. The frequency measurement is performed synchronously with the signal input.

When the V1 level is less than 10% of the rated voltage, the integration cycle is fixed to approximately 125 milliseconds.

Range of frequency measured: 45 to 65 Hz

Provision of Lowpass Filter

A lowpass filter with the cutoff frequency of 300 Hz is built into the frequency measurement circuit for eliminating noise from the input signal and assuring accurate frequency measurement.

8-8

IM CW120-E

8.5 Sampling Cycle and Integration Cycle

Synchronously with the zero crossing signal for the input voltage V1, the time period from when a cycle of zero-crossing begins until a cycle of zero crossing occurs immediately next after a specified period (100 milliseconds) has elapsed, is set to the integration cycle, and the rms voltage, rms current, and power are calculated.

Sampling frequency: Approx. 10 kHz

Integration cycle: 120 ms

Frequency

measurement

input V1

(sine wave)

Zero-crossing

signal

50 Hz

20 ms

Examples

Frequency (Hz)

50 60

100 ms

Integration Cycle (ms)

120

116.67

Number of Waves

6 7

Instantaneous Value Measurement

IM CW120-E

8-9

Chapter 9. Electric Energy Measurement

9.1 Measuring Electric Energy

The CW120/121 power meters have two modes for measurement:

1. Instantaneous value measurement: Measures the rms voltages and rms current of individual phases, and power, reactive power, power factor, and frequency.

This section describes electric energy measurement.

● Displayed Data

As the values measured and displayed, those related to active electric energy are added to the values during instantaneous value measurement.

During Instantaneous Value Measurement

Item

Rms voltage

Rms current

Active power

Reactive power Power factor

Frequency

Unit

Var

—

During Electric Energy Measurement

Item

Active electric energy Elapsed time of

integration

(Regenerative electric energy)*

Unit

Hour:minute:second

Hour:minute

Hour

Electric Energy Measurement

Displayed Name

V1, V2, V3 (differs depending on the wiring method)

A1, A2, A3 (differs depending on the wiring method)

W, W1, W2, W3 (differs depending on the wiring method)

Var, Var1, Var2, Var3 (differs depending on the wiring method)

PF, PF1, PF2, PF3 Hz (input frequency of V1)

Displayed Name

Wh, Wh1, Wh2, Wh3 00:00:00TIME

0000:00TIME 00000hTIME

The display format changes over between the above automatically depending on the elapsed time.

The values are not displayed on the screen, but only saved.

* Stands for the integrated, reversal power flow.

IM CW120-E

9-1

Yokogawa CW120, CW121 Operating Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Introduction

Checking Items in the Package

Precautions for Safe Use of the Instrument

Contents

Chapter 1. Product Overview

1.1 Product Overview

Chapter 2. Components and Indications

2.1 Front Panel and Connector Block

2.2 Connecting Input Signals

2.3 Operation Keys and Display

2.4 Overrange and Other Marks Shown during Measurement

Chapter 3. Precautions for Safe Measurement

3.1 Handling Precautions

3.2 Installation Procedure

3.3 Maintaining High Precision of Measurement

Chapter 4. Connecting Power Supply and Turning Power On/Off

4.1 When Using AC Power Supply

4.3 Startup Screens

4.4 Basic Operation Flow

Chapter 5. Wiring

5.1 Precautions for Wiring the Circuit under Test

5.2 Diagrams of Basic Wiring

5.3 Wiring the Circuit under Test with External VT/CT

5.5 Wiring Check Function

Chapter 6. Setting Ranges and Wiring Method

6.1 Ranges and Display Digits

6.2 Changing Voltage Range Setting

6.3 Changing Current Range Setting

6.4 Changing Wiring Method Setting

Chapter 7. Making Settings

7.1 Setting Items and Item Selection

7.2 Setting Each Item

7.3 Setting Name of Measured-data File

Chapter 8. Instantaneous Value Measurement

8.1 Measuring Instantaneous Values

8.2 Switching Display Contents

8.3 Saving Data

8.4 Frequency Measurement

8.5 Sampling Cycle and Integration Cycle

Chapter 9. Electric Energy Measurement

9.1 Measuring Electric Energy