Yokogawa PR300 User Manual

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User’s Manual

Model PR300 Power and Energy Meter Communication Interface

(RS-485 and Ethernet Communications)

IM 77C01E01-10E

4th Edition

Introduction

This user's manual describes the communication functions of the PR300 power and energy meter and contains information on how to create communication programs.

Hereafter, the PR300 power and energy meter is simply referred to as the PR300. Read the manual carefully to understand the communication functions of the PR300 .

The PR300 has the following communication protocols.

● PC link communication protocol

● Modbus /RTU and Modbus/ASCII communication protocols

● Modbus/TCP communication protocol (for the PR300 with Ethernet communication

function)

● PR201 original communication protocol

You are required to have background knowledge of the communication specifications of higher-level devices, their communication hardware, language used for creating communication programs, and so on.

■ Intended Readers

This manual is intended for people familiar with the functions of the PR300, control engineers and personnel in charge of maintaining instrumentation and control equipment.

■ Related Documents

The following user's manuals all relate to the communication functions of the PR300. Read them as necessary.

● Model PR300 Power and Energy Meter User's Manual (electronic manual) Document number: IM 77C01E01-01E

● Model PR300 Power and Energy Meter Startup Manual <Installation> Document number: IM 77C01E01-02E

● Model PR300 Power and Energy Meter Startup Manual <Initial Setup Operations> Document number: IM 77C01E01-03E

These manuals provide information about the procedure of installation, wiring and operation.

■ Trademark

(1) All the brands or names of Yokogawa Electric's products used in this manual are

either trademarks or registerd trademarks of Yokogawa Electric Corporation.

(2) Ethernet is a registered trademark of XEROX Corporation in the United States. (3) Company and product names that appear in this manual are trademarks or registered

trademarks of their respective holders.

IM 77C01E01-10E

Documentation Conventions

■ Symbols

This manual uses the following symbols.

● Symbols Used in the Main Text

NOTE

Draws attention to information that is essential for understanding the operation and/or features of the product.

TIP

Gives additional information to complement the present topic.

See Also

Gives reference locations for further information on the topic.

● Symbols Used in Figures and Tables

[NOTE]

Draws attention to information that is essential for understanding the features of the product.

[TIP]

Gives additional information to complement the present topic.

[See Also]

Gives reference locations for further information on the topic.

■ Description of Displays

(1) Some of the representations of product displays shown in this manual may be exag-

gerated, simplified, or partially omitted for reasons of convenience when explaining them.

(2) Figures and illustrations representing the PR300's displays may differ from the real

displays in regard to the position and/or indicated characters (upper-case or lowercase, for example), the extent of difference does not impair a correct understanding of the functions and the proper operations and monitoring of the system.

IM 77C01E01-10E

Notices

■ Regarding This User's Manual

(1) This manual should be passed on to the end user. Keep the manual in a safe place. (2) Read this manual carefully to gain a thorough understanding of how to operate this

product before you start using it.

(3) This manual is intended to describe the functions of this product. Yokogawa Electric

Corporation (hereinafter simply referred to as Yokogawa) does not guarantee that these functions are suited to the particular purpose of the user.

(4) Under absolutely no circumstance may the contents of this manual, in part or in whole,

be transcribed or copied without permission.

(5) The contents of this manual are subject to change without prior notice. (6) Every effort has been made to ensure accuracy in the preparation of this manual.

Should any errors or omissions come to your attention however, please contact your nearest Yokogawa representative or our sales office.

(7) The document concerning TCP/IP software has been created by Yokogawa based on

the BSD Networking Software, Release 1 that has been licensed from the University of California.

iii

■ Regarding Protection, Safety, and Prohibition Against Unauthorized Modification

(1) In order to protect the product and the system controlled by it against damage and

ensure its safe use, be certain to strictly adhere to all of the instructions and precautions relating to safety contained in this document. Yokogawa does not guarantee safety if products are not handled according to these instructions.

(2) The following safety symbols are used on the product and/or in this manual.

● Symbols Used on the Product and in This Manual

This symbol on the product indicates that the operator must refer to an explanation in the user's manual in order to avoid the risk of injury or death of personnel or damage to the instrument. The manual describes how the operator should exercise special care to avoid electric shock or other dangers that may result in injury or loss of life.

Protective Grounding Terminal This symbol indicates that the terminal must be connected to ground prior to operating

the equipment.

IM 77C01E01-10E

■ Force Majeure

(1) Yokogawa does not make any warranties regarding the product except those men-

tioned in the WARRANTY that is provided separately.

(2) Yokogawa assumes no liability to any party for any loss or damage, direct or indirect,

caused by the use or any unpredictable defect of the product.

(3) Be sure to use the spare parts approved by Yokogawa when replacing parts or

consumables. (4) Modification of the product is strictly prohibited. (5) Reverse engineering such as the disassembly or decompilation of software is strictly

prohibited. (6) No portion of the software supplied by Yokogawa may be transferred, exchanged,

leased, or sublet for use by any third party without the prior permission of Yokogawa.

IM 77C01E01-10E

Model PR300 Power and Energy Meter Communication Interface

Toc-1

(RS-485 and Ethernet Communications)

IM 77C01E01-10E 4th Edition

Introduction........................................................................................................... i

Documentation Conventions ...............................................................................ii

Notices .................................................................................................................iii

1. Communications Overview

1.1 RS-485 Communication Specifications ......................................................... 1-1

1.2 Ethernet Communication Specifications....................................................... 1-1

2. Setup

2.1 Setup Procedure ............................................................................................. 2-1

2.1.1 Procedure for RS-485 Communication ............................................. 2-2

2.1.2 Procedure for Ethernet Communication ............................................ 2-3

2.1.3 Procedure for Ethernet-Serial Gateway Function .............................. 2-4

2.2 Setting Communication Conditions .............................................................. 2-6

2.2.1 Conditions for RS-485 Communication ............................................. 2-6

2.2.2 Conditions for Ethernet Communication ............................................ 2-8

2.2.3 Conditions for Ethernet-Serial Gateway Function ............................ 2-10

2.3 Wiring for Communication ........................................................................... 2-12

2.3.1 Wiring for RS-485 Communication .................................................. 2-12

2.3.2 Wiring for Ethernet Communication ................................................ 2-13

2.3.3

Wiring for RS-485 Communication for Ethernet-Serial Gateway Function ..

2-14

3. Procedures for Setting PR300 Functions

3.1 Basic Setting ................................................................................................... 3-2

3.1.1 Setting of VT Ratio ............................................................................ 3-2

3.1.2 Setting of CT Ratio............................................................................ 3-3

3.1.3 Setting of Integrated Low-cut Power ................................................. 3-4

3.2 Setting Pulse Output....................................................................................... 3-5

3.2.1 Selection of Measurement Item for Pulse Output .............................. 3-5

3.2.2 Pulse Unit ......................................................................................... 3-6

3.2.3 ON Pulse Width ................................................................................ 3-7

3.3 Setting Analog Output .................................................................................... 3-8

3.3.1 Selection of Measurement Item for Analog Output ............................ 3-8

3.3.2 Upper/Lower Limits of Scaling .......................................................... 3-9

3.4 Demand Setting ............................................................................................ 3-10

3.4.1 Demand Power/Current .................................................................. 3-10

3.4.2 Demand Period................................................................................3-11

3.4.3 Demand Alarm Mask Time .............................................................. 3-12

3.4.4 Demand Power Alarm Point ............................................................ 3-13

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Toc-2

3.4.5 Demand Current Alarm Point .......................................................... 3-14

3.4.6 Demand Alarm Release Function ................................................... 3-15

3.5 Communication Setting ................................................................................ 3-16

3.5.1 Protocol .......................................................................................... 3-16

3.5.2 Baud Rate ...................................................................................... 3-17

3.5.3 Parity .............................................................................................. 3-18

3.5.4 Stop Bit ........................................................................................... 3-19

3.5.5 Data Length .................................................................................... 3-20

3.5.6 Station Number............................................................................... 3-21

3.5.7 IP Address (for Ethernet communication) ........................................ 3-22

3.5.8 Subnet Mask (for Ethernet communication) .................................... 3-23

3.5.9 Default Gateway (for Ethernet communication) ............................... 3-24

3.5.10 Port Number (for Ethernet communication) ..................................... 3-25

3.6 Writing Energy Values .................................................................................. 3-26

3.6.1 Active Energy ................................................................................. 3-26

3.6.2 Regenerative Energy ...................................................................... 3-27

3.6.3 LEAD Reactive Energy ................................................................... 3-28

3.6.4 LAG Reactive Energy ..................................................................... 3-29

3.6.5 Apparent Energy............................................................................. 3-30

3.7 Executing Reset Operations ........................................................................ 3-31

3.7.1 Remote Reset ................................................................................ 3-31

3.7.2 Maximum/Minimum Values Reset ................................................... 3-32

3.7.3 Energy Value All-Reset ................................................................... 3-32

3.7.4 Active Energy Reset ....................................................................... 3-33

3.7.5 Regenerative Energy Reset ............................................................ 3-33

3.7.6 Reactive Energy Reset ................................................................... 3-34

3.7.7 Apparent Energy Reset .................................................................. 3-34

3.8 Setting Control States .................................................................................. 3-35

3.8.1 Integration Start/Stop ..................................................................... 3-35

3.8.2 Optional Integration Start/Stop ........................................................ 3-36

3.8.3 Demand Measurement Start/Stop................................................... 3-37

3.8.4 Confirmation and Release of Demand Alarm State ......................... 3-38

4. PC Link Communication Protocol

4.1 Overview.......................................................................................................... 4-1

4.1.1 Configuration of Command ............................................................... 4-2

4.1.2 Configuration of Response ............................................................... 4-3

4.1.3 Response Error Codes ..................................................................... 4-4

4.1.4 Specifying Broadcast ........................................................................ 4-5

4.2 Command and Response ............................................................................... 4-6

WRD Reads D registers on a word-by-word basis ................................... 4-7

WWR Writes data into D registers on a word-by-word basis..................... 4-8

WRR Reads D registers on a word-by-word basis in random order......... 4-9

WRW WRS

WRM Monitors the D registers on a word-by-word basis ........................ 4-12

INF6 Reads the model, suffix codes, and version information............... 4-13

INF7 Reads the maximum value of CPU ............................................... 4-14

4.3 Communication with Higher-level Devices ................................................. 4-15

4.3.1 Communication with FA-M3 (UT Link Module) ................................ 4-15

Writes data into D registers on a word-by-word basis in random order ...

Specifies the D registers to be monitored on a word-by-word basis ........

4-10 4-11

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5. Modbus/RTU and ASCII Communication Protocols

6. Modbus/TCP Communication Protocol

Toc-3

4.4 Sample Program ........................................................................................... 4-17

4.4.1 Example of BASIC Program for Send and Receive ......................... 4-17

5.1 Overview.......................................................................................................... 5-1

5.1.1 Configuration of Message ................................................................. 5-3

5.1.2 Specifying D Registers...................................................................... 5-4

5.1.3 Checking Errors ................................................................................ 5-4

5.1.4 Configuration of Response ............................................................... 5-7

5.1.5 Specifying Broadcast ........................................................................ 5-9

5.2 Message and Response ............................................................................... 5-10

03 Reads data from multiple D registers ............................................ 5-11

06 Writes data into D register ............................................................. 5-12

08 Performs loop back test................................................................. 5-13

16 Writes data into multiple D registers .............................................. 5-14

6.1 Overview.......................................................................................................... 6-1

6.2 TCP/IP Communication .................................................................................. 6-3

6.3 Network Frame Structure ............................................................................... 6-4

6.3.1 MBAP Header Structure ................................................................... 6-4

6.3.2 PDU Structure .................................................................................. 6-4

6.4 Communication with Higher-level Devices ................................................... 6-5

6.4.1 List of Function Codes ...................................................................... 6-5

6.4.2 Specifying D Registers...................................................................... 6-5

6.4.3 Request and Response .................................................................... 6-6

03 Reads data from multiple D registers .............................................. 6-6

06 Writes data into D register ............................................................... 6-7

08 Performs loop back test................................................................... 6-8

16 Writes data into multiple D registers ................................................ 6-9

6.4.4 Response Error Codes .................................................................... 6-11

6.5 Sample Program ........................................................................................... 6-12

6.5.1 Example of BASIC Program for Send and Receive ......................... 6-12

7. Functions and Usage of D Registers

7.1 Overview of D Registers ................................................................................. 7-1

7.2 Configuration of D Registers.......................................................................... 7-1

7.3 Interpretation of D Register Map Table .......................................................... 7-1

7.4 D Register Map ................................................................................................ 7-2

8. PR201 Original Communication Protocol

8.1 Overview.......................................................................................................... 8-1

8.2 Communication Specifications ...................................................................... 8-1

8.3 Command/Response Format ......................................................................... 8-2

8.4 List of Commands........................................................................................... 8-3

8.5 Command Details............................................................................................ 8-5

Appendix Table of ASCII Codes (Alphanumeric Codes) Revision Information

IM 77C01E01-10E

1. Communications Overview

1.1 RS-485 Communication Specifications

Protocols available for RS-485 communication interfaces include the PC link communication protocol and the Modbus communication protocol.

Table 1.1 RS-485 Communication Specifications

Item Details Connected Device Communication Hardware Compliant Standard

Protocol Specification

Baud Rate Maximum Communication Distance Maximum Number of

Connectable Devices Transmission Method Synchronization Communication Method Communication Cable

2-wire system RS-485 EIA RS-485

PC Link Communication with and without checksum

Modbus Communication (ASCII and RTU modes)

PR201 original communication

2400 bps, 9600 bps, 19200 bps 1200 m

31 2-wire, half-duplex

Start-stop synchronization Non-procedural Shielded twisted pair cable

(AWG24-equivalent size)

A PC installed with a driver for PC link communication and SCADA software, PLC (FA-M3 UT link module), etc.

A PC installed with a Modbus driver and SCADA software, a Modbus-compatible PLC, etc.

Personal computer etc. with SCADA software installed to support PR201 original communication protocol

1-1

1.2 Ethernet Communication Specifications

Protocols available for Ethernet communication interfaces include the Modbus/TCP communication protocol.

Table 1.2 Ethernet Communication Specifications

Item Details

Communication Hardware Compliant Standard Access Control Protocol Specification Baud Rate Maximum Segment Length Maximum Connecting

Configuration Communication System Data Format Maximum Number of

Connections *1: Distance between the hub and module.

*2: The number of hubs connectable in cascade configuration.

10BASE-T/100BASE-TX Ethernet IEEE802.3 CSMA/CD Modbus communication (Port No.: 502) 10 Mbps/100 Mbps 100 m *1 Cascade max. 4 levels (for 10BASE-T)

max. 2 levels (for 100BASE-TX) *2 TCP/IP Binary 1

Connected Device

Ethernet-equipped PC etc.

IM 77C01E01-10E

2. Setup

This chapter describes how to set up the PR300, which is equipped with RS-485 communication as a standard feature.

When using an Ethernet-equipped model, either RS-485 or Ethernet can be selected by parameter setting for communications.

For details of use of RS-485 communication, see subsection 2.1.1 “Procedure for RS-485 Communication.”

For details of use of the Ethernet communication, see subsection 2.1.2 “Procedure for Ethernet Communication.”

For details of use of the Ethernet-serial gateway function, see subsection 2.1.3 “Procedure for Ethernet-Serial Gateway Function.”

2.1 Setup Procedure

Set up the communication functions on the PR300 as follows:

2-1

WARNING

To avoid an electric shock, be sure to turn off the power supply source to the equipment involved before you start wiring.

Note: Create communication programs referring to the user’s manual for communications of each higher-level device.

Higher-level devices : PCs, PLCs (sequencers), and others.

IM 77C01E01-10E

2.1.1 Procedure for RS-485 Communication

(Example)

Higher-level device

Maximum communication distance: 1200 m Maximum number of slave stations to be connected: 31

2-2

Station number 01

(arbitrary)

Communication parameters setting for PR300

Set up the communication function using the front panel keys.

Connect a higher-level device with PR300

Create communication programs for the

higher-level device to perform communication

Station number 02

(arbitrary)

Subsection 2.2.1 “Conditions for RS-485 Communication”

Subsection 2.3.1 “Wiring for RS-485 Communication”

Chapter 3 “Procedures for Setting PR300 Functions”

For communication protocol, see Chapter 4 “PC Link Communication Protocol” Chapter 5

Modbus/RTU and ASCII Communication Protocols

“ Chapter 8 “PR201 Original Communication Protocol”

For data storage location, see Chapter 7 “Functions and Usage of D Registers”

See

Station number 10

(arbitrary)

Station number 20

(arbitrary)

”

IM 77C01E01-10E

2.1.2 Procedure for Ethernet Communication

(Example)

2-3

Higher-level device IP address [192.168.1.1]

HUB

LAN connection

Station number 01 (fixed) IP address [192.168.1.2] (arbitrary)

Communication parameters setting for PR300

Set up the communication function using

(arbitrary)

Ethernet

Station number 01 (fixed) IP address [192.168.1.3] (arbitrary)

the front panel keys.

See

Subsection 2.2.2 “Conditions for Ethernet Communication”

Connect a higher-level device with PR300

See

Subsection 2.3.2 “Wiring for Ethernet Communication”

Maximum distance between hub and module: 100 m Maximum number of hubs connectable in cascade configuration: 4 levels for 10BASE-T 2 levels for 100BASE-TX

Station number 01 (fixed) IP address [192.168.1.4] (arbitrary)

Station number 01 (fixed) IP address [192.168.1.5] (arbitrary)

Create communication programs for the

higher-level device to perform communication

See

Chapter 3 “Procedures for Setting PR300 Functions”

For communication protocol, see Chapter 6

“Modbus/TCP Communication Protocol”

For data storage location, see Chapter 7 “Functions and Usage of D Registers”

Note: It is recommended to use the Ethernet network as a dedicated one for the

PR300.

IM 77C01E01-10E

2.1.3 Procedure for Ethernet-Serial Gateway Function

(Example)

Higher-level device IP address [192.168.1.1] (arbitrary)

Ethernet

2-4

PR300

communication function)

(with Ethernet

Communication parameters setting for PR300

Set up the communication function using the front panel keys.

Connect a higher-level device with PR300

RS-485

Station number 02

(arbitrary)

Subsection 2.2.2 “Conditions for Ethernet Communication” Subsection 2.2.3 “

Subsection 2.3.2 “Wiring for Ethernet Communication”

Station number 01 (fixed) IP address [192.168.1.2] (arbitrary)

Station number 03

(arbitrary)

See

Conditions for Ethernet-Serial Gateway Function

See

Station number 20

(arbitrary)

”

Connect a lower-level device with PR300

See

Subsection 2.3.3 “Wiring for RS-485 Communication for Ethernet-Serial Gateway Function”

Create communication programs for the

higher-level device to perform communication

Note: It is recommended to use the Ethernet network as a dedicated one for the PR300.

See

Chapter 3 “Procedures for Setting PR300 Functions”

For communication protocol, see Chapter 6

“Modbus/TCP Communication Protocol”

For data storage location, see Chapter 7 “Functions and Usage of D Registers”

IM 77C01E01-10E

●

VJET Ethernet/RS-485 converter as an Ethernet-serial gateway function

(Example)

Higher-level device IP address [192.168.1.1] (arbitrary)

Ethernet

2-5

Ethernet/RS-485 converter

VJET*

RS-485

Station number 02 (arbitrary) Station number 03 (arbitrary)

* The VJET is Yokogawa’s converter. For details of use of the VJET, refer to its user’s manual.

Note: It is recommended to use the Ethernet network as a dedicated one for the PR300.

The communication conditions of any slave PR300 must conform to those of the VJET at a higher level.

Station number 01 (fixed) IP address [192.168.1.2] (arbitrary)

Station number 20 (arbitrary)

IM 77C01E01-10E

2.2 Setting Communication Conditions

This section describes the setting parameters for using the communication functions, and the setting ranges. For details of setting method, refer to the PR300 Power and Energy Meter User’s Manual (electronic manual).

2.2.1 Conditions for RS-485 Communication

This subsection describes the setting parameters for using the RS-485 communication function, and the setting ranges.

Table 2.1 Parameters to be Set for Communication Functions

Parameter Name

Parameter Symbol

Setting Range

2-6

Initial

Value

Station number

Protocol

Baud rate

Parity*

Stop bit*

(RS-485

communication)

(ST-NO)

(COMM)

(B-RT)

(PRI)

(STP)

01 to 99 (01 to 31 recommended)

PC link without checksum

PC link with checksum

Modbus/ASCII

Modbus/RTU

Modbus/TCP*

PR201 original

(PCLK1)

(PCLK2)

(M ASC)

(M RTU)

(M TCP)

(PR201)

2400 bps 9600 bps 19200 bps

None

Even

Odd

(NONE)

(EVEN)

(ODD)

PCLK2

9600

NONE

Data length*2 *

*1: Modbus/TCP can be selected for the PR300 with Ethernet communication function only. *2: When Modbus /RTU is selected for the protocol, select 8 for the data length. If 7 is selected for the data length,

communication is not possible.

*3: When PR201 original is selected for the protocol, select NONE for the parity, 1 for the stop bit and 8 for the data length.

(DLN)

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● Protocol (COMM)

Set the communication protocol identical to that of the higher-level device to be connected.

● Station number (ST-NO)

Set the station number of the PR300 itself. A station number of 01 to 99 may be assigned in any order. However, the maximum number of PR300 to be connected to a single communication port is 31.

When connecting two or more PR300 to a single communication port, set a different station number to each.

Example of connecting a higher-level device with four PR300 having station numbers 01, 05, 10, and 20

(Example)

Higher-level device

2-7

Maximum communication distance: 1200 m Maximum number of slave sations to be connected: 31

Station number 01

(arbitrary)

Station number 05

(arbitrary)

Station number 10

(arbitrary)

Station number 20

(arbitrary)

● Baud rate (B-RT)

Set the baud rate identical to that of the higher-level device to be connected. (Otherwise, proper communication cannot be achieved.)

● Parity (PRI)

Set the handling of parity to be carried out when data is sent or received. Set the parity bit state identical to that of the higher-level device to be connected.

* When PR201 original is selected for the protocol, select NONE for the parity.

● Stop bit (STP)

Set the stop bit identical to that of the higher-level device to be connected.

* When PR201 original is selected for the protocol, select 1 for the stop bit.

● Data length (DLN)

Set the same data length as for the upper device that is to be connected.

* When Modbus/RTU is selected for the protocol, select 8 for the data length. * When PR201 original is selected for the protocol, select 8 for the data length.

IM 77C01E01-10E

2.2.2 Conditions for Ethernet Communication

This subsection describes the setting parameters for using the Ethernet communication function, and the setting ranges.

Table 2.2 Parameters to be Set for Communication Functions

Parameter Name

Parameter Symbol

Setting Range

2-8

Initial

Value

Protocol

IP address-1

IP address-2

IP address-3

IP address-4

Subnet mask-1

Subnet mask-2

(RS-485

Communication)

(COMM)

(IP-1)

(IP-2)

(IP-3)

(IP-4)

(SM-1)

(SM-2)

PC link without checksum

PC link with checksum

Modbus/ASCII

Modbus/RTU

Modbus/TCP*

PR201 original

0 to 255

(PCLK1)

(PCLK2)

(M ASC)

(M RTU)

(M TCP)

(PR201)

PCLK2

192

168

255

Subnet mask-3

(SM-3)

(Ethernet

Subnet mask-4

Communication)

(SM-4)

Default gateway-1

(DG-1)

Default gateway-2

(DG-2)

Default gateway-3

(DG-3)

Default gateway-4

(DG-4)

Port number

(PORT)

Ethernet setting switch

(E-SW)

*1: Modbus/TCP can be selected for the PR300 with Ethernet communication function only. *2: Ethernet communication menu is displayed when Modbus/TCP is selected for the protocol.

0 to 255

502, 1024 to 65535

OFF, ON

255

502

IM 77C01E01-10E

● Protocol (COMM)

Set the protocol to Modbus/TCP.

● IP address-1 to 4 (IP-n) [n: integers from 1 to 4]

Set the IP address for the PR300 by the following format.

2-9

0 to 255

IP address IP-1

0 to 255

IP-2

0 to 255

IP-3

0 to 255

IP-4

● Subnet mask-1 to 4 (SM-n) [n: integers from 1 to 4]

Set the subnet mask for the PR300 by the following format.

0 to 255

Subnet Mask SM-1

0 to 255

SM-2

0 to 255

SM-3

0 to 255

SM-4

● Default gateway-1 to 4 (DG-n) [n: integers from 1 to 4]

Set the default gateway for the PR300 by the following format.

0 to 255

Default Gateway DG-1

0 to 255

DG-2

0 to 255

DG-3

0 to 255

DG-4

NOTE

Before performing setup of IP address, subnet mask, and default gateway, consult the administrator for the network to which the PR300 is to be connected.

● Port number (PORT)

Set the port number for the PR300.

NOTE

To activate the settings of IP address, subnet mask, default gateway, and port number, set the Ethernet setting switch to ‘ON’ after setting them.

● Ethernet setting swtich (E-SW)

This switch activates the Ethernet communication parameters settings. Setting this parameter to ON activates the settings of IP address, subnet mask, default gateway, and port number.

This parameter automatically reverts to OFF in about 20 seconds after being set to ON.

IM 77C01E01-10E

2.2.3 Conditions for Ethernet-Serial Gateway Function

The Ethernet-serial gateway function is a function that reads/writes data from/to other devices equipped with RS-485 serial communication function using the Modbus/TCP protocol via the PR300.

With this function, the higher-level device can access the devices connected to the RS-485 serial communication line in the same way as to access the devices connected to Ethernet.

(Example)

Higher-level device

2-10

PR300

communication function)

Device with RS-485 serial communication function

Power Monitor of POWERCERT series Digital indicating controller of GREEN series Signal conditioner of JUXTA series

(with Ethernet

Ethernet

RS-485

Station number 02

(arbitrary)

10BASE-T, 100BASE-TX

Station number 01 (fixed)

Station number 03

(arbitrary)

Station number 04

(arbitrary)

The PR300 operates as a gateway that changes the Modbus/TCP protocol received via network to the Modbus/RTU protocol for the serial devices connected to the RS-485 communication interface. Therefore, the devices supporting the Modbus/RTU protocol are required for the devices to be connected.

NOTE

• If the Ethernet-serial gateway function is used, set a station number other than 01 for the RS-485 communication devices which are slaves of the PR300 connected to Ethernet.

• If the Ethernet communication function is used, the RS-485 communication interface is used specifically for the Ethernet-serial gateway function. Therefore, it is not possible for a higher-level device such as a PC to access the PR300 via the RS-485 communication interface.

IM 77C01E01-10E

● Setting for PR300 to perform the Ethernet-serial gateway function

To use the Ethernet-serial gateway function, set the parameters of subsection 2.2.2, “Conditions for Ethernet Communication” and set a parity (PRI) in Table 2.3.

When the protocol is set to Modbus/TCP, the parameters of RS-485 other than the parity are fixed and unchangeable.

Table 2.3 Parameters of PR300 to Perform the Ethernet-Serial Gateway Function

Parameter Name

Menu Setting Range

Parameter Symbol

2-11

Initial Value

Station number

Baud rate

Parity

Stop bit

Data length

(RS-485

communication)

(ST-NO)

(B-RT)

(PRI)

(STP)

(DLN)

01 (fixed)

9600 bps (fixed)

None Even

Odd

1 (fixed)

8 (fixed)

NONE EVEN ODD

● Slave PR300

The station number of any slave PR300 (device for RS-485 communication) must be a different number other than 01.

The communication conditions for any slave PR300 (device for RS-485 communication) other than the station number must conform to those in Table 2.3.

Table 2.4 Parameters of Slave PR300

Parameter Name

Station number

Baud rate

Parity

Stop bit

Menu Setting Range

(RS-485

communication)

Parameter Symbol

(ST-NO)

(B-RT)

(PRI)

(STP)

02 to 99

2400 bps 9600 bps 19200 bps

None Even Odd

NONE EVEN ODD

9600

NONE

Initial

Value

9600

NONE

Data length

(DLN)

When using the VJET Ethernet/RS-485 converter as an Ethernet-serial gateway function, the communication conditions of any slave PR300 must conform to those of the VJET at a higher level. The initial value of the VJET parity is EVEN.

IM 77C01E01-10E

2.3 Wiring for Communication

Connect a higher-level device with the PR300 for using the communication functions. The wiring procedures and precautionary notes are as follows.

2.3.1 Wiring for RS-485 Communication

For a common PC, the RS-485 interface is not directly connectable. Use a ML2 RS232C/ RS485 converter for wiring.

WARNING

To avoid an electric shock, be sure to turn off the power supply source to the equipment involved before you start wiring.

Use crimp-on terminals at cable ends. Before you start wiring, read the user’s manual of each device.

PR300 (with RS-485 communication function)

Aⴚ

Bⴙ

(RS232C/RS485 converter)

Terminator

120Ω 1/4W

Aⴚ

Bⴙ

PR300 (with RS-485 communication function)

2-12

Terminator (built-in)

120Ω 1/4W

Wthen terminating on wiring, short-circuit terminals 17 and 18 .

RS-232C straight cable

JIS Class D (3) grounding (grounding resistance of 100Ω or less)

Communication cableCommunication cable

JIS Class D (3) grounding (grounding resistance of 100Ω or less)

Note: Use UL Listed RS-232C/RS-485 converter if the converter has AC/DC power supply input; this is

optional for converters supplied by a Limited Power Source with input voltages less than 30 V AC or 60 V DC and which are separated from mains by double or reinforced insulation.

Communication cable: Shielded twisted pair cable (AWG24-eqivalent size) Recommended terminals: See the PR300 Power and Energy Meter User’s Manual (electronic manual).

IM 77C01E01-10E

2.3.2 Wiring for Ethernet Communication

To use the Ethernet communication function, connect a higher-level device with the PR300 with Ethernet communication function using 10BASE-T/100BASE-TX. 10BASE-T/ 100BASE-TX are Ethernet connection methods using twisted pair cables. The transmission rates are 10 Mbps/100 Mbps. In 10BASE-T/100BASE-TX networks, higher-level devices such as a PC are connected in a star pattern through a hub.

WARNING

To avoid an electric shock, be sure to turn off the power supply source to the equipment involved before you start wiring.

Use hubs and twisted pair cables that conforms to the Ethernet specifications. The maximum number of hubs connectable in cascade configuration is 4 for 10ABSE-T and 2 for 100BASE-TX. The maximum allowable length of twisted pair cables is 100 meters.

Read the user’s manual of each device carefully before wiring.

* Devices that can be connected to Ethernet

2-13

PR300 with Ethernet communication function

HUB

Data transmission

and reception

Ethernet

Ethernet Port of PR300

The PR300 can detect 10BASE-T or 100BASE-TX automatically. The LEDs of Ethernet port show its status.

Link LED (upper side) Color Off Amber Green Activity LED (lower side) Color Off Amber Green

Meaning No Link 10 Mbps 100 Mbps

Meaning No Activity Half-duplex Full-duplex

IM 77C01E01-10E

2.3.3 Wiring for RS-485 Communication for Ethernet-Serial Gateway Function

To use the Ethernet-serial gateway function, connect other RS-485 serial communication device to the RS-485 communication terminals .

WARNING

To avoid an electric shock, be sure to turn off the power supply source to the equipment involved before you start wiring.

The figure below shows the example of wiring connection for the PR300 with Ethernet communication function. If other devices are used for connection, the names of communication terminals and others may be different from those mentioned in the figure.

Read the user’s manual of each device carefully before wiring.

2-14

(with Ethernet

communication function)

Terminator (built-in)

120Ω 1/4W

Wthen terminating on wiring, short-circuit terminals 17 and 18 .

Ethernet

PR300

(with RS-485

17 17

Aⴚ

Bⴙ

Communication

cable

communication function)

2020

JIS Class D (3) grounding

(grounding resistance

of 100Ω or less)

Communication

cable

PR300

(with RS-485

communication function)

Aⴚ

Bⴙ

Terminator (built-in)

120Ω 1/4W

Wthen terminating on wiring, short-circuit terminals 17 and 18 .

IM 77C01E01-10E

3-1

3. Procedures for Setting PR300 Functions

To set the functions of the PR300, use the protocols described in Chapter 4, “PC Link Communication Protocol,” Chapter 5, “Modobus/RTU and ASCII Communication Protocols,” or Chapter 6, “Modbus/TCP Communication Protocol” according to the instructions in this chapter.

For details of each function, refer to the PR300 Power and Energy Meter User’s Manual (electronic manual).

For how to read the tables in this chapter, refer to Chapter 7, “Functions and Usage of D Registers.”

The PR300 offers registers for floating-point data. To perform settings via communication from higher-level device, floating-point data is displayed by IEEE754 (single precision).

NOTE

• The PR300 has data (D register) the unit of which is two words. When 2-word data need to be written or read, writing or reading operations must be performed for the 2word data at the same time.

• Even if data written to the D register is out of the effective range, a normal response is returned. The part of the written data within the effective range becomes effective on the PR300 when the equivalent setting change status is written for that data.

IM 77C01E01-10E

3.1 Basic Setting

3.1.1 Setting of VT Ratio

[Procedure]

(1) Write a VT ratio to the two D registers in the table below. The data type is 4-byte

floating point.

(2) After writing that value, write 1 to the setup change status register, D0207.

3-2

D Register

D0201 D0202

D0207

Initial value of VT ratio: 1 (4-byte floating-point data: 3F800000)

Reference No.

40201 40202

40207

H No.

00C8 00C9

00CE

VT ratio (float, lower 2 bytes) VT ratio (float, upper 2 bytes) Setup change status

(D0201 to D0206 are validated)

Description

Effective Range

1 to 6000

If other than 1: Invalid If 1: Writing is executed

[Example]

To set the VT ratio to 10: For station number 01, use PC link communication (without checksum) and the random

write command as shown below: If 10 is converted into a 4-byte floating-point value, the value is 4120 0000.

[Command] [STX] 01010WRW03D0201, 0000, D0202, 4120, D0207, 0001 [ETX] [CR] [Response] [STX] 0101OK [ETX] [CR]

NOTE

• When changing the VT ratio, the integrated values of active energy, reactive energy, apparent energy, optional active energy, and regenerative energy will return to “0.” The values of the demand alarm point and the scaling of analog output will also be initialized.

• Set the VT and CT ratios so that [secondary rated power] × [VT ratio] × [CT ratio] is smaller than 10 GW. When this value is 10 GW or greater, writing to D registers will be invalid (no error is output).

IM 77C01E01-10E

3.1.2 Setting of CT Ratio

[Procedure]

(1) Write a CT ratio to the two D registers in the table below. The data type is 4-byte

floating point.

(2) After writing that value, write 1 to the setup change status register, D0207.

3-3

D Register

D0203 D0204

D0207

Initial value of CT ratio: 1 (4-byte floating-point data: 3F800000)

Reference No.

40203 40204

40207

H No.

00CA 00CB

00CE

CT ratio (float, lower 2 bytes) CT ratio (float, upper 2 bytes) Setup change status

(D0201 to D0206 are validated)

Description

Effective Range

0.05 to 32000

If other than 1: Invalid If 1: Writing is executed

[Example]

To set the CT ratio to 10.0: For station number 01, use PC link communication (without checksum) and the random

write command as shown below: If 10.0 is converted into a 4-byte floating-point value, the value is 4120 0000.

[Command] [STX] 01010WRW03D0203, 0000, D0204, 4120, D0207, 0001 [ETX] [CR] [Response] [STX] 0101OK [ETX] [CR]

NOTE

• When changing the CT ratio, the integrated values of active energy, reactive energy, apparent energy, optional active energy, and regenerative energy will return to “0.” The values of the demand alarm point and the scaling of analog output will also be initialized.

IM 77C01E01-10E

3.1.3 Setting of Integrated Low-cut Power

[Procedure]

(1) Write an integrated low-cut power value to the two D registers in the table below. The

data type is 4-byte floating point.

(2) After writing that value, write 1 to the setup change status register, D0207.

3-4

D Register

D0205

D0206

D0207

Initial value of integrated low-cut power: 0.05% (4-byte floating-point data: 3D4CCCCD)

Reference No.

40205

40206

40207

H No.

00CC

00CD

00CE

Description

Integrated low-cut power (float, lower 2 bytes)

Integrated low-cut power (float, upper 2 bytes)

Setup change status (D0201 to D0206 are validated)

Effective Range

0.05 to 20.00 Unit: %

If other than 1: Invalid If 1: Writing is executed

[Example]

To set the integrated low-cut power value to 10.0%: For station number 01, use PC link communication (without checksum) and the random

write command as shown below: If 10.0 is converted into a 4-byte floating-point value, the value is 4120 0000.

[Command] [STX] 01010WRW03D0205, 0000, D0206, 4120, D0207, 0001 [ETX] [CR] [Response] [STX] 0101OK [ETX] [CR]

IM 77C01E01-10E

3.2 Setting Pulse Output

3.2.1 Selection of Measurement Item for Pulse Output

[Procedure]

(1) Write a measurement item for pulse output value to the D register in the table below.

The data type is integer.

(2) After writing that value, write 1 to the pulse output writing status register, D0211.

3-5

D Register

D0208

D0211

Initial value of measurement item for pulse output: 0 (active energy)

Reference No.

40208

40211

H No.

00CF

00D2

Description

Measurement item for pulse output

Pulse output writing status (D0208, D0209, and D0210 are validated)

Effective Range

0: Active energy 1: Regenerative energy 2: LEAD reactive energy 3: LAG reactive energy 4: Apparent energy

If other than 1: Invalid If 1: Writing is executed

[Example]

To set the measurement item for pulse output to 1 (LEAD reactive energy): For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX] 01010WRW02D0208, 0001, D0211, 0001 [ETX] [CR] [Response] [STX] 0101OK [ETX] [CR]

NOTE

• A measurement item for pulse output value can be set for the PR300 with pulse output.

• When the PR300 is the three-phase four-wire system (2.5 element), the following measurement items can be measured only when the current is in a state of equilibrium: “2: LEAD reactive energy”, “3: LAG reactive energy” and “4: Apparent energy.”

IM 77C01E01-10E

3.2.2 Pulse Unit

[Procedure]

(1) Write a pulse unit value to the D register in the table below. The data type is integer. (2) After writing that value, write 1 to the pulse output writing status register, D0211.

3-6

D Register

D0209

D0211

Initial value of pulse unit: 10 (1000 Wh/pulse)

Reference No.

40209

40211

H No.

00D0

00D2

Description

Pulse unit

Pulse output writing status (D0208, D0209, and D0210 are validated)

Effective Range

1 to 50,000 Unit:  100 Wh/pulse

If other than 1: Invalid If 1: Writing is executed

[Example]

To set the pulse unit to 100 Wh/pulse, write “0001.” For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX]01010WRW02D0209,0001,D0211,0001[ETX][CR] [Response] [STX]0101OK[ETX][CR]

NOTE

• A pulse unit value can be set for the PR300 with pulse output.

• To set the pulse unit value via communication, set it to 1/100 the value of the displayed

(true) value (e.g., set it to 5 when setting the pulse unit value to 500 Wh/pulse).

IM 77C01E01-10E

3.2.3 ON Pulse Width

(1) Write an ON pulse width value to the D register in the table below. The data type is

integer.

(2) After writing that value, write 1 to the pulse output writing status register, D0211.

NOTE

When the value to be set for the ON pulse width is greater than the value calculated by the following equation, the value cannot be set:

3-7

ON pulse width (ms) 

D Register

D0210

D0211

Initial value of ON pulse width: 5 (50 ms)

Reference No.

40210

40211

Secondary rated power [W]  VT ratio  CT ratio  1.2  2

00D1

00D2

H No.

Pulse unit [Wh/pls]  60  60  1000

Description

ON pulse width

Pulse output writing status (D0208, D0209, and D0210 are validated)

Effective Range

1 to 127 Unit:  10 ms

If other than 1: Invalid If 1: Writing is executed

[Example]

To set the ON pulse width to 100 ms, write “000A.” For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX] 01010WRW02D0210, 000A, D0211, 0001 [ETX] [CR] [Response] [STX] 0101OK [ETX] [CR]

NOTE

• An ON pulse width value can be set for the PR300 with pulse output.

• To set the ON pulse width value via communication, set it to 1/10 the value of the

displayed (true) value (e.g., set it to 5 when setting the ON pulse width value to 50 ms).

IM 77C01E01-10E

3.3 Setting Analog Output

3.3.1 Selection of Measurement Item for Analog Output

[Procedure]

(1) Write a measurement item for analog output value to the D register in the table below.

The data type is integer.

(2) After writing that value, write 1 to the analog output writing status register, D0217.

3-8

D Register

D0212

D0217

Initial value of measurement item for analog output: 0 (active power)

Reference No.

40212

40217

H No.

00D3

00D8

Description

Measurement item for analog output

Analog output writing status (D0212 to D0216 are validated)

Effective Range

0: Active power 1: Reactive power 2: Apparent power 3: Voltage-1 4: Voltage-2 5: Voltage-3 6: Current-1 7: Current-2 8: Current-3 9: Power factor 10: Frequency

If other than 1: Invalid If 1: Writing is executed

[Example]

To set the measurement item for analog output to 3 (voltage-1): For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX] 01010WRW02D0212, 0003, D0217, 0001 [ETX] [CR] [Response] [STX] 0101OK [ETX] [CR]

NOTE

• A measurement item for analog output value can be set for the PR300 with analog output.

• Different types of the PR300 can measure different items, and so the values that can be set to the D register differ depending on the PR300 type. If a value that cannot be written to the D register is written, it will be invalid. The table below shows the values that cannot be set for four types of the PR300:

Phase and Wire System Single-phase two-wire Single-phase three-wire Three-phase three-wire Three-phase four-wire (2.5 element)

4: Voltage-2, 5: Voltage-3, 7: Current-2, and 8: Current-3 5: Voltage-3 and 8: Current-3 4: Voltage-2 and 7: Current-2 4: Voltage-2 and 7: Current-2

• When the PR300 is the three-phase four-wire system (2.5 element), the following measurement items can be measured only when the current is in a state of equilibrium: “1: Reactive power”, “2: Apparent power”, “6: Current-1”, “8: Current-3” and “9: Power factor.”

Values that cannot be Set

IM 77C01E01-10E

3.3.2 Upper/Lower Limits of Scaling

[Procedure]

(1) Write upper/lower limits of scaling value to the four D registers in the table below. The

data type is 4-byte floating point.

(2) After writing that value, write 1 to the analog output writing status register, D0217.

3-9

D Register

D0213

D0214

D0215

D0216

D0217

Initial value of lower limit of scaling: 50% Initial value of upper limit of scaling: 100%

Reference No.

40213

40214 00D5

40215 00D6

40216 00D7

40217

H No.

00D4

00D8

Description

Lower limit of scaling (float, lower 2 bytes)

Lower limit of scaling (float, upper 2 bytes)

Upper limit of scaling (float, lower 2 bytes)

Upper limit of scaling (float, upper 2 bytes)

Analog output writing status (D0212 to D0216 are validated)

Effective Range

0.0 to 50.0 Unit: %

50.0 to 100.0 Unit: %

If other than 1: Invalid If 1: Writing is executed

[Example]

To set the lower limit of scaling to 10.0%: For station number 01, use PC link communication (without checksum) and the random

write command as shown below: If 10.0 is converted into a 4-byte floating point value, the value is 4120 0000.

[Command] [STX] 01010WRW03D0213, 0000, D0214, 4120, D0217,0001 [ETX] [CR] [Response] [STX] 0101OK [ETX] [CR]

NOTE

• An upper/lower limit of scaling value can be set for the PR300 with analog output.

• Set an upper/lower limit of scaling so that [upper limit of scaling] – [lower limit of

scaling] is 50% or greater. If it is smaller than 50%, writing to the D register will be invalid.

IM 77C01E01-10E

3.4 Demand Setting

3.4.1 Demand Power/Current

[Procedure]

(1) Write a demand power/current value to the D register in the table below. The data type

is integer.

(2) After writing that value, write 1 to the demand measurement writing status register,

D0226.

3-10

D Register

D0218

D0226

Initial value of demand power/current: 0 (active power)

Reference No.

40218

40226

H No.

00D9

00E1

Description

Demand power/current

Demand measurement writing status (D0218 to D0225 are validated)

Effective Range

0: Active power 1: Current

If other than 1: Invalid If 1: Writing is executed

[Example]

To set the demand power/current to 1 (current): For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX] 01010WRW02D0218, 0001, D0226, 0001 [ETX] [CR] [Response] [STX] 0101OK [ETX] [CR]

NOTE

• A demand power/current value can be set for the PR300 with demand measuring function.

• When the PR300 is the three-phase four-wire system (2.5 element), “1: Current” can be measured only when the current is in a state of equilibrium.

IM 77C01E01-10E

3.4.2 Demand Period

[Procedure]

(1) Write a demand period value to the D register in the table below. The data type is

integer.

(2) After writing that value, write 1 to the demand measurement writing status register,

D0226.

3-11

D Register

D0219

D0226

Initial value of demand period: 30 minutes

Reference No.

40219

40226

00DA

00E1

H No.

Description

Demand period

Demand measurement writing status (D0218 to D0225 are validated)

Effective Range

1 to 60 (Demand alarm mask time to 60) Unit: minute

If other than 1: Invalid If 1: Writing is executed

[Example]

To set the demand period to 20 minutes: For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX] 01010WRW02D0219, 0014, D0226, 0001 [ETX] [CR] [Response] [STX] 0101OK [ETX] [CR]

NOTE

A demand period value can be set for the PR300 with demand measuring function.

IM 77C01E01-10E

3.4.3 Demand Alarm Mask Time

[Procedure]

(1) Write a demand alarm mask time value to the D register in the table below. The data

type is integer.

(2) After writing that value, write 1 to the demand measurement writing status register,

D0226.

3-12

D Register

D0220

D0226

Initial value of demand alarm mask time: 1 minute

Reference No.

40220

40226

H No.

00DB

00E1

Description

Demand alarm mask time

Demand measurement writing status (D0218 to D0225 are validated)

Effective Range

1 to 59 (1 to demand period)

Unit: minute

If other than 1: Invalid If 1: Writing is executed

[Example]

To set the demand alarm mask time to 20 minutes: For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX]01010WRW02D0220,0014,D0226,0001[ETX][CR] [Response] [STX]0101OK[ETX][CR]

NOTE

A demand alarm mask time value can be set for the PR300 with demand measuring

function.

IM 77C01E01-10E

3.4.4 Demand Power Alarm Point

[Procedure]

(1) Write a demand power alarm point value to the two D registers in the table below. The

data type is 4-byte floating point.

(2) After writing that value, write 1 to the demand measurement writing status register,

D0226.

3-13

D Register

D0221

D0222

D0226

Initial value of demand power alarm point: 100 kW

Reference No.

40221

40222 00DD

40226

H No.

00DC

00E1

Description

Demand power alarm point (float, lower 2 bytes)

Demand power alarm point (float, upper 2 bytes)

Demand measurement writing status (D0218 to D0225 are validated)

Effective Range

1 to 1000 Unit: kW

If other than 1: Invalid If 1: Writing is executed

[Example] To set the demand power alarm point to 10.0 kW: For station number 01, use PC link communication (without checksum) and the random

write command as shown below: If 10.0 is converted into a 4-byte floating point value, the value is 4120 0000.

[Command] [STX]01010WRW03D0221,0000,D0222,4120,D0226,0001[ETX][CR] [Response] [STX]0101OK[ETX][CR]

NOTE

A demand power alarm point value can be set for the PR300 with demand measuring

function.

IM 77C01E01-10E

3.4.5 Demand Current Alarm Point

[Procedure]

(1) Write a demand current alarm point value to the two D registers in the table below.

The data type is 4-byte floating point.

(2) After writing that value, write 1 to the demand measurement writing status register,

D0226.

3-14

D Register

D0223

D0224

D0226

Initial value of demand current alarm point: 100 A

Reference No.

40223

40224 00DF

40226

H No.

00DE

00E1

Description

Demand current alarm point (float, lower 2 bytes)

Demand current alarm point (float, upper 2 bytes)

Demand measurement writing status (D0218 to D0225 are validated)

Effective Range

1 to 1000 Unit: A

If other than 1: Invalid If 1: Writing is executed

[Example]

To set the demand current alarm point to 10.0 A: For station number 01, use PC link communication (without checksum) and the random

write command as shown below: If 10.0 is converted into a 4-byte floating point value, the value is 4120 0000.

[Command] [STX]01010WRW03D0223,0000,D0224,4120,D0226,0001[ETX][CR] [Response] [STX]0101OK[ETX][CR]

NOTE

A demand current alarm point value can be set for the PR300 with demand measuring

function.

IM 77C01E01-10E

3.4.6 Demand Alarm Release Function

[Procedure]

(1) Write a demand alarm release function value to the D register in the table below. The

data type is integer.

(2) After writing that value, write 1 to the demand measurement writing status register,

D0226.

3-15

D Register

D0225

D0226

Initial value of demand alarm release function: 0 (automatic release)

Reference No.

40225

40226

H No.

00E0

00E1

Description

Demand alarm release function

Demand measurement writing status (D0218 to D0225 are validated)

Effective Range

0: Automatic

1: Manual release

If other than 1: Invalid If 1: Writing is executed

release

[Example]

To set the demand alarm release function to 0 (automatic release): For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX]01010WRW02D0225,0000,D0226,0001[ETX][CR] [Response] [STX]0101OK[ETX][CR]

NOTE

• A demand alarm release function value can be set for the PR300 with demand measuring function.

• When the demand alarm release function is used by digital input, releasing via communication is not possible.

IM 77C01E01-10E

3.5 Communication Setting

3.5.1 Protocol

[Procedure]

(1) Write a protocol value to the D register in the table below. The data type is integer. (2) After writing that value, write 1 to the RS-485 writing status register, D0277.

3-16

D Register

D0271

D0277

Initial value of protocol: 1 (PC link with checksum) *1: Modbus/TCP can be selected for the PR300 with Ethernet communication function only.

Reference No.

40271

40277

H No.

010E

0114

Description

Protocol

RS-485 writing status (D0271 to D0276 are validated)

Effective Range

0: PC link (without checksum) 1: PC link (with checksum) 2: Modbus/ASCII 3: Modbus/RTU 4: Modbus/TCP * 5: PR201 original

If other than 1: Invalid If 1: Writing is executed

NOTE

• When Modbus/TCP is selected for the protocol, the baud rate, the stop bit, the data length and the station number are fixed and unchangeable.

• When PR201 original is selected, the baud rate, the parity, the stop bit and the data length cannot be set via communication.

[Example]

To set the protocol to 4 (Modbus/TCP): For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX]01010WRW02D0271,0004,D0277,0001[ETX][CR]

[Response] [STX]0101OK[ETX][CR]

IM 77C01E01-10E

3.5.2 Baud Rate

[Procedure]

(1) Write a baud rate value to the D register in the table below. The data type is integer. (2) After writing that value, write 1 to the RS-485 writing status register, D0277.

3-17

D Register

D0272

D0277

Initial value of baud rate: 1 (9600 bps)

Reference No.

40272

40277

H No.

010F

0114

Description

Baud rate

RS-485 writing status (D0271 to D0276 are validated)

Effective Range

0: 2400 bps 1: 9600 bps 2: 19200 bps

If other than 1: Invalid If 1: Writing is executed

NOTE

When Modbus/TCP is selected for the protocol, the baud rate is fixed and unchangeable at 9600 bps.

[Example]

To set the baud rate to 2 (19200 bps): For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX]01010WRW02D0272,0002,D0277,0001[ETX][CR]

[Response] [STX]0101OK[ETX][CR]

IM 77C01E01-10E

3.5.3 Parity

[Procedure]

(1) To set the parity, write data to the D register in the table below. The data type is integer. (2) After writing that value, write 1 to the RS-485 writing status register, D0277.

3-18

D Register

D0273

D0277

Initial value of parity: 0 (NONE)

Reference No.

40273

40277

H No.

0110

0114

Description

Parity

RS-485 writing status (D0271 to D0276 are validated)

Effective Range

0: NONE 1: EVEN 2: ODD

If other than 1: Invalid If 1: Writing is executed

[Example]

To set the parity to 1 (EVEN): For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX]01010WRW02D0273,0001,D0277,0001[ETX][CR]

[Response] [STX]0101OK[ETX][CR]

IM 77C01E01-10E

3.5.4 Stop Bit

[Procedure]

(1) To set the stop bit, write data to the D register in the table below. The data type is

integer.

(2) After writing that value, write 1 to the RS-485 writing status register, D0277.

3-19

D Register

D0274

D0277

Initial value of stop bit: 1 (1 bit)

Reference No.

40274

40277

H No.

0111

0114

Description

Stop bit

RS-485 writing status (D0271 to D0276 are validated)

Effective Range

1: 1 bit 2: 2 bits

If other than 1: Invalid If 1: Writing is executed

NOTE

When Modbus/TCP is selected for the protocol, the stop bit is fixed and unchangeable at 1 bit.

[Example]

To set the stop bit to 2 (2 bits): For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX]01010WRW02D0274,0002,D0277,0001[ETX][CR]

[Response] [STX]0101OK[ETX][CR]

IM 77C01E01-10E

3.5.5 Data Length

[Procedure]

(1) To set the data length, write data to the D register in the table below. The data type is

integer.

(2) After writing that value, write 1 to the RS-485 writing status register, D0277.

3-20

D Register

D0275

D0277

Initial value of data length: 0 (8 bits)

Reference No.

40275

40277

H No.

0112

0114

Description

Data length

RS-485 writing status (D0271 to D0276 are validated)

Effective Range

0: 8 bits 1: 7 bits

If other than 1: Invalid If 1: Writing is executed

NOTE

When Modbus/TCP is selected for the protocol, the data length is fixed and unchangeable at 8 bits.

[Example]

To set the data length to 1 (7 bits): For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX]01010WRW02D0275,0001,D0277,0001[ETX][CR]

[Response] [STX]0101OK[ETX][CR]

IM 77C01E01-10E

3.5.6 Station Number

[Procedure]

(1) To set the station number, write data to the D register in the table below. The data type

is integer.

(2) After writing that value, write 1 to the RS-485 writing status register, D0277.

3-21

D Register

D0276

D0277

Initial value of station number: 01

Reference No.

40276

40277

H No.

0113

0114

Description

Station number

RS-485 writing status (D0271 to D0276 are validated)

Effective Range

01 to 99

If other than 1: Invalid If 1: Writing is executed

NOTE

When Modbus/TCP is selected for the protocol, the station number is fixed and unchangeable at 01.

[Example]

To set the station number to 02: For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX]01010WRW02D0276,0002,D0277,0001[ETX][CR]

[Response] [STX]0101OK[ETX][CR]

IM 77C01E01-10E

3.5.7 IP Address (for Ethernet communication)

[Procedure]

(1) To set the IP address, write data to the four D registers in the table below. The data

type is integer.

(2) After writing that value, write 1 to the Ethernet writing status register, D0294.

3-22

D Register

D0281 D0282 D0283 D0284

D0294

Initial value of IP address: 192.168.1.1

Reference No.

40281 40282 40283 40284

40294

H No.

0118 0119 011A 011B

0125

0 to 255

IP address IP-1

Description

IP address-1 (IP-1) IP address-2 (IP-2) IP address-3 (IP-3) IP address-4 (IP-4)

Ethernet writing status (D0281 to D0293 are validated)

0 to 255

IP-2

0 to 255

IP-3

Effective Range

0 to 255 0 to 255 0 to 255 0 to 255

If other than 1: Invalid If 1: Writing is executed

0 to 255

IP-4

NOTE

• An IP address value can be set for the PR300 with Ethernet communication function.

• IP address settings are only effective when the protocol is set to Modbus/TCP.

[Example]

To set the IP address to 192.168.1.3: For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX]01010WRW05D0281,00C0,D0282,00A8,D0283,0001,D0284,0003,D0294,0001[ETX][CR]

[Response] [STX]0101OK[ETX][CR]

IM 77C01E01-10E

3.5.8 Subnet Mask (for Ethernet communication)

[Procedure]

(1) To set the subnet mask, write data to the four D registers in the table below. The data

type is integer.

(2) After writing that value, write 1 to the Ethernet writing status register, D0294.

3-23

D Register

D0285 D0286 D0287 D0288

D0294

Initial value of subnet mask: 255.255.255.0

Reference No.

40285 40286 40287 40288

40294

Subnet Mask

H No.

011C 011D 011E 011F

0125

Description

Subnet mask-1 (SM-1) Subnet mask-2 (SM-2) Subnet mask-3 (SM-3) Subnet mask-4 (SM-4)

Ethernet writing status (D0281 to D0293 are validated)

0 to 255

SM-1

0 to 255

SM-2

0 to 255

SM-3

Effective Range

0 to 255 0 to 255 0 to 255 0 to 255

If other than 1: Invalid If 1: Writing is executed

0 to 255

SM-4

NOTE

• A subnet mask value can be set for the PR300 with Ethernet communication function.

• Subnet mask settings are only effective when the protocol is set to Modbus/TCP.

[Example]

To set the subnet mask to 255. 255. 255. 0: For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX]01010WRW05D0285,00FF,D0286,00FF,D0287,00FF,D0288,0000,D0294,0001[ETX][CR]

[Response] [STX]0101OK[ETX][CR]

IM 77C01E01-10E

3.5.9 Default Gateway (for Ethernet communication)

[Procedure]

(1) To set the default gateway, write data to the four D registers in the table below. The

data type is integer.

(2) After writing that value, write 1 to the Ethernet writing status register, D0294.

3-24

D Register

D0289 D0290 D0291 D0292

D0294

Initial value of default gateway: 0.0.0.0

Reference No.

40289 40290 40291 40292

40294

H No.

0120 0121 0122 0123

0125

Default Gateway

Description

Default gateway-1 (DG-1) Default gateway-2 (DG-2) Default gateway-3 (DG-3) Default gateway-4 (DG-4)

Ethernet writing status (D0281 to D0293 are validated)

0 to 255

DG-1

0 to 255

DG-2

Effective Range

0 to 255 0 to 255 0 to 255 0 to 255

If other than 1: Invalid If 1: Writing is executed

0 to 255

DG-3

0 to 255

DG-4

NOTE

• A default gateway value can be set for the PR300 with Ethernet communication function.

• Default gateway settings are only effective when the protocol is set to Modbus/TCP.

[Example]

To set the default gateway to 0. 0. 0. 0: For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX]01010WRW05D0289,0000,D0290,0000,D0291,0000,D0292,0000,D0294,0001[ETX][CR]

[Response] [STX]0101OK[ETX][CR]

IM 77C01E01-10E

3.5.10 Port Number (for Ethernet communication)

[Procedure]

(1) To set the port number, write data to the D register in the table below. The data type is

integer.

(2) After writing that value, write 1 to the Ethernet writing status register, D0294.

3-25

D Register

D0293

D0294

Initial value of port number: 502

Reference No.

40293

40294

H No.

0124

0125

Description

Port number

Ethernet writing status (D0281 to D0293 are validated)

Effective Range

502, 1024 to 65535

If other than 1: Invalid If 1: Writing is executed

NOTE

• A port number value can be set for the PR300 with Ethernet communication function.

• Port number setting is only effective when the protocol is set to Modbus/TCP.

[Example]

To set the port number to 1024: For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX]01010WRW02D0293,0400,D0294,0001[ETX][CR]

[Response] [STX]0101OK[ETX][CR]

IM 77C01E01-10E

3.6 Writing Energy Values

3.6.1 Active Energy

[Procedure]

(1) Write an active energy value to the two D registers in the table below. The data type is

integer.

(2) After writing that value, write 1 to the writing status register, D0373.

3-26

D Register

D0371

D0372 40372 0173

D0373 40373 0174

Reference No.

40371

H No.

0172

Description

Active energy-setpoint (lower 2 bytes)

Active energy-setpoint (upper 2 bytes)

Active energy value writing status

Effective Range

Refer to the "NOTE" below.

If other than 1: Invalid If 1: Writing is executed

[Example]

To set the active energy value to 10,000,000 kWh: For station number 01, use PC link communication (without checksum) and the random

write command as shown below: If 10,000,000 is converted into a hexadecimal value, the value is 0098 9680. Then the

order of the upper two bytes and the lower two bytes is reversed ⇒ 9680 0098.

[Command] [STX] 01010WRW03D0371, 9680, D0372, 0098, D0373, 0001 [ETX] [CR]

[Response] [STX] 0101OK [ETX] [CR]

NOTE

The set active energy value range of the PR300 changes depending on the values of the VT and CT ratios. The table below shows the set value range.

[Secondary Rated Power]  [VT Ratio]  [CT Ratio]

Less than 100 kW 100 kW to less than 1 MW 1 MW to less than 10 MW 10 MW or greater

Possible Set Value Range

0 to 99999 kWh 0 to 999999 kWh 0 to 9999999 kWh 0 to 99999999 kWh

NOTE

The secondary rated power of the PR300 changes depending on its model and suffix codes.

IM 77C01E01-10E

3.6.2 Regenerative Energy

[Procedure]

(1) Write a regenerative energy value to the two D registers in the table below. The data

type is integer.

(2) After writing that value, write 1 to the writing status register, D0376.

3-27

D Register

D0374

D0375 40375 0176

D0376 40376 0177

Reference No.

40374

H No.

0175

Description

Regenerative energy-setpoint (lower 2 bytes)

Regenerative energy-setpoint (upper 2 bytes)

Regenerative energy writig status

Effective Range

Refer to the "NOTE" below.

If other than 1: Invalid If 1: Writing is executed

[Example]

To set the regenerative energy value to 10,000,000 kWh: For station number 01, use PC link communication (without checksum) and the random

write command as shown below: If 10,000,000 is converted into a hexadecimal value, the value is 0098 9680. Then the

order of the upper two bytes and the lower two bytes is reversed ⇒ 9680 0098.

[Command] [STX] 01010WRW03D0374, 9680, D0375, 0098, D0376, 0001 [ETX] [CR]

[Response] [STX] 0101OK [ETX] [CR]

NOTE

The set regenerative energy value range of the PR300 changes depending on the values of the VT and CT ratios. The table below shows the set value range.

[Secondary Rated Power]  [VT Ratio]  [CT Ratio]

Less than 100 kW 100 kW to less than 1 MW 1 MW to less than 10 MW 10 MW or greater

Possible Set Value Range

0 to 99999 kWh 0 to 999999 kWh 0 to 9999999 kWh 0 to 99999999 kWh

NOTE

The secondary rated power of the PR300 changes depending on its model and suffix codes.

IM 77C01E01-10E

3.6.3 LEAD Reactive Energy

[Procedure]

(1) Write a LEAD reactive energy value to the two D registers in the table below. The data

type is integer.

(2) After writing that value, write 1 to the writing status register, D0381.

3-28

D Register

D0377

D0378 40378 0179

D0381 40381 017C

Reference No.

40377

H No.

0178

Description

LEAD reactive energy-setpoint (lower 2 bytes)

LEAD reactive energy-setpoint (upper 2 bytes)

Reactive energy writing status (D0377 to D0380 are validated)

Effective Range

Refer to the "NOTE" below.

If other than 1: Invalid If 1: Writing is executed

[Example]

To set the LEAD reactive energy value to 10,000,000 kVarh: For station number 01, use PC link communication (without checksum) and the random

write command as shown below: If 10,000,000 is converted into a hexadecimal value, the value is 0098 9680. Then the

order of the upper two bytes and the lower two bytes is reversed ⇒ 9680 0098.

[Command] [STX] 01010WRW03D0377, 9680, D0378, 0098, D0381, 0001 [ETX] [CR]

[Response] [STX] 0101OK [ETX] [CR]

NOTE

The set LEAD reactive energy value range of the PR300 changes depending on the values of the VT and CT ratios. The table below shows the set value range.

[Secondary Rated Power]  [VT Ratio]  [CT Ratio]

Less than 100 kW 100 kW to less than 1 MW 1 MW to less than 10 MW 10 MW or greater

Possible Set Value Range

0 to 99999 kvarh 0 to 999999 kvarh 0 to 9999999 kvarh 0 to 99999999 kvarh

NOTE

The secondary rated power of the PR300 changes depending on its model and suffix codes.

IM 77C01E01-10E

3.6.4 LAG Reactive Energy

[Procedure]

(1) Write a LAG reactive energy value to the two D registers in the table below. The data

type is integer.

(2) After writing that value, write 1 to the writing status register, D0381.

3-29

D Register

D0379

D0380 40380 017B

D0381 40381 017C

Reference No.

40379

H No.

017A

Description

LAG reactive energy-setpoint (lower 2 bytes)

LAG reactive energy-setpoint (upper 2 bytes)

Reactive energy writing status (D0377 to D0380 are validated)

Effective Range

Refer to the "NOTE" below.

If other than 1: Invalid If 1: Writing is executed

[Example]

To set the LAG reactive energy value to 10,000,000 kVarh: For station number 01, use PC link communication (without checksum) and the random

write command as shown below: If 10,000,000 is converted into a hexadecimal value, the value is 0098 9680. Then the

order of the upper two bytes and the lower two bytes is reversed ⇒ 9680 0098.

[Command] [STX] 01010WRW03D0379, 9680, D0380, 0098, D0381, 0001 [ETX] [CR]

[Response] [STX] 0101OK [ETX] [CR]

NOTE

The set LAG reactive energy value range of the PR300 changes depending on the values of the VT and CT ratios. The table below shows the set value range.

[Secondary Rated Power]  [VT Ratio]  [CT Ratio]

Less than 100 kW 100 kW to less than 1 MW 1 MW to less than 10 MW 10 MW or greater

Possible Set Value Range

0 to 99999 kvarh 0 to 999999 kvarh 0 to 9999999 kvarh 0 to 99999999 kvarh

NOTE

The secondary rated power of the PR300 changes depending on its type.

IM 77C01E01-10E

3.6.5 Apparent Energy

[Procedure]

(1) Write an apparent energy value to the two D registers in the table below. The data

type is integer.

(2) After writing that value, write 1 to the writing status register, D0384.

3-30

D Register

D0382

D0383 40383 017E

D0384 40384 017F

Reference No.

40382

H No.

017D

Description

Apparent energy-setpoint (lower 2 bytes)

Apparent energy-setpoint (upper 2 bytes)

Apparent energy writing status

Effective Range

Refer to the "NOTE" below.

If other than 1: Invalid If 1: Writing is executed

[Example]

To set the apparent energy value to 10,000,000 kVAh: For station number 01, use PC link communication (without checksum) and the random

write command as shown below: If 10,000,000 is converted into a hexadecimal value, the value is 0098 9680. Then the

order of the upper two bytes and the lower two bytes is reversed ⇒ 9680 0098.

[Command] [STX] 01010WRW03D0382, 9680, D0383, 0098, D0384, 0001 [ETX] [CR]

[Response] [STX] 0101OK [ETX] [CR]

NOTE

The set apparent energy value range of the PR300 changes depending on the values of the VT and CT ratios. The table below shows the set value range.

[Secondary Rated Power]  [VT Ratio]  [CT Ratio]

Less than 100 kW 100 kW to less than 1 MW 1 MW to less than 10 MW 10 MW or greater

Possible Set Value Range

0 to 99999 kVAh 0 to 999999 kVAh 0 to 9999999 kVAh 0 to 99999999 kVAh

NOTE

The secondary rated power of the PR300 changes depending on its model and suffix codes.

IM 77C01E01-10E

3.7 Executing Reset Operations

3.7.1 Remote Reset

[Procedure]

(1) To execute remote reset, write data to the D register in the table below. The data type

is integer.

3-31

D Register

D0400

Initial value of remote reset: 0

Reference No.

40400

H No.

018F

Description

Remote reset

Effective Range

If other than 1: Invalid If 1: PR300 reset

NOTE

• When remote reset is executed, maximum, minimum and instantaneous voltage values and maximum and instantaneous current values will be reset. Optional integration is terminated if it is being performed.

• Even when remote reset is executed, active energy, reactive energy, and apparent energy data as well as set parameter values are retained.

[Example]

To execute remote reset: For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX] 01010WRW01D0400, 0001 [ETX] [CR]

[Response] [STX] 0101OK [ETX] [CR]

NOTE

After remote reset is executed, wait for 10 seconds or more before sending another command. It takes about 10 seconds to reset. Even when PR300 was reset by power supply switch off/on, also wait for 10 seconds or more before sending another command.

IM 77C01E01-10E

3.7.2 Maximum/Minimum Values Reset

[Procedure]

(1) To execute maximum/minimum values reset, write data to the D register in the table

below. The data type is integer.

3-32

D Register

D0351

Reference No.

40351

H No.

015E

[Example]

To execute maximum/minimum values reset: For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX]01010WRW01D0351,0001[ETX][CR]

[Response] [STX]0101OK[ETX][CR]

3.7.3 Energy Value All-Reset

[Procedure]

Description

Maximum/minimum values (D0101 to D0138) reset

Effective Range

If other than 1: Invalid If 1: Maximum/minimum values reset

(1) To execute energy value all-reset, write data to the D register in the table below. The

data type is integer.

D Register

D0352

Reference No.

40352

H No.

015F

Description

Energy value all-reset

Relevant items are as follows: Active energy (D0001, D0002) Regenerative energy (D0003, D0004) LEAD reactive energy (D0005, D0006) LAG reactive energy (D0007, D0008) Apparent energy (D0009, D0010)

If other than 1: Invalid If 1: Energy value all-reset

Effective Range

[Example]

To execute energy value all-reset: For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX]01010WRW01D0352,0001[ETX][CR]

[Response] [STX]0101OK[ETX][CR]

IM 77C01E01-10E

3.7.4 Active Energy Reset

[Procedure]

(1) To execute active energy reset, write data to the D register in the table below. The

data type is integer.

3-33

D Register

D0353

Reference No.

40353

H No.

0160

Active energy (D0001 and D0002) reset

[Example]

To execute active energy reset: For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX] 01010WRW01D0353, 0001 [ETX] [CR]

[Response] [STX] 0101OK [ETX] [CR]

3.7.5 Regenerative Energy Reset

[Procedure]

(1) To execute regenerative energy reset, write data to the D register in the table below.

The data type is integer.

Description

Effective Range

If other than 1: Invalid If 1: Active energy reset

D Register

D0354

Reference No.

40354

H No.

0161

Description

Regenerative energy (D0003 and D0004) reset

Effective Range

If other than 1: Invalid If 1: Regenerative energy reset

[Example]

To execute regenerative energy reset: For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX] 01010WRW01D0354, 0001 [ETX] [CR]

[Response] [STX] 0101OK [ETX] [CR]

IM 77C01E01-10E

3.7.6 Reactive Energy Reset

[Procedure]

(1) To execute reactive energy reset, write data to the D register in the table below. The

data type is integer.

3-34

D Register

D0355

Reference No.

40355

H No.

0162

[Example]

To execute reactive energy reset: For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX] 01010WRW01D0355, 0001 [ETX] [CR]

[Response] [STX] 0101OK [ETX] [CR]

3.7.7 Apparent Energy Reset

[Procedure]

Description

Reactive energy (D0005 to D0008) reset

Effective Range

If other than 1: Invalid If 1: Reactive energy reset

(1) To execute apparent energy reset, write data to the D register in the table below. The

data type is integer.

D Register

D0356

Reference No.

40356

H No.

0163

Description

Apparent energy (D0009 and D0010) reset

Effective Range

If other than 1: Invalid If 1: Apparent energy reset

[Example]

To execute apparent energy reset: For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX] 01010WRW01D0356, 0001 [ETX] [CR]

[Response] [STX] 0101OK [ETX] [CR]

IM 77C01E01-10E

3.8 Setting Control States

3.8.1 Integration Start/Stop

[Procedure]

(1) To execute integration start/stop, write data to the D register in the table below. The

data type is integer.

3-35

D Register

D0301

Initial value of integration start/stop: 1 (start)

Reference No.

40301

H No.

012C

Description

Integration start/stop

Relevant items are as follows: Active energy (D0001, D0002) Regenerative energy (D0003, D0004) LEAD reactive energy (D0005, D0006) LAG reactive energy (D0007, D0008) Apparent energy (D0009, D0010)

0: Stop 1: Start

Effective Range

[Example]

To execute integration start/stop: For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

<For start> [Command] [STX] 01010WRW01D0301, 0001 [ETX] [CR] [Response] [STX] 0101OK [ETX] [CR]

<For stop> [Command] [STX] 01010WRW01D0301, 0000 [ETX] [CR] [Response] [STX] 0101OK [ETX] [CR]

IM 77C01E01-10E

3.8.2 Optional Integration Start/Stop

[Procedure]

(1) To execute optional integration start/stop, write data to the D register in the table

below. The data type is integer.

3-36

D Register

D0302

Initial value of optional integration start/stop: 0 (stop)

Reference No.

40302

H No.

012D

Description

Optional integration start/stop Relevant D registers: D0011 to D0014

Effective Range

0: Stop 1: Start

NOTE

Optional integration start/stop can also be controlled by digital input. Once digital input is performed, it is the only means for such control. Control via communication is no longer possible until the power is turned off or remote reset is executed (see subsection 3.7.1). However, for the PR300 with demand measuring function, digital input is used to release the demand alarm. In this case, optional integration start/stop cannot be used.

[Control via communication]

START command STOP command

Digital input turned on Digital input turned off Data update

Perform integration for this duration

Time

No response to digital input requests

[Control by digital input]

Digital input turned on Digital input turned off

START

command

Perform integration for this duration

STOP

command

No response to requests via communication

Time

Data update

[Example]

To execute optional integration start/stop: For station number 01, use PC link communication (without checksum) and the random

write command as shown below:

[Command] [STX]01010WRW01D0302,0001[ETX][CR]

[Response] [STX]0101OK[ETX][CR]

IM 77C01E01-10E

3.8.3 Demand Measurement Start/Stop

[Procedure]

(1) To execute demand measurement start/stop, write data to the D register in the table

below. The data type is integer.

3-37

D Register

D0311

Initial value of demand measurement start/stop: 0 (measurement stop)

Reference No.

40311

H No.

0136

Description

Demand measurement start/stop

Relevant items are as follows: Demand power (D0043, D0044) Demand current (D0045 to D0050)

Effective Range

0: Measurement stop 1: Measurement start

NOTE

Demand measurement start/stop can also be controlled by operation key. Once the operation key is used, it is the only means for such control. Control via communication is not possible until the power is turned off, or remote reset is executed (see subsection 3.7.1).

[Control via communication]

START command STOP command

Turned on by operation key Turned off by operation key

[Control by operation key]

Turned on by operation key Turned off by operation key

Perform integration for this duration

Time

Data update

No response to requests by operation key

Perform integration for this duration

Time

START

command

STOP

command

Data update

No response to requests via communication

[Example]

To execute demand measurement start/stop: For station number 01, use PC link communication (without checksum) and the random

write command as shown below: <For start>

[Command] [STX]01010WRW01D0311,0001[ETX][CR]

[Response] [STX]0101OK[ETX][CR]

<For stop> [Command] [STX]01010WRW01D0311,0000[ETX][CR] [Response] [STX]0101OK[ETX][CR]

NOTE

Demand measurement start/stop can be performed for the PR300 with demand measuring function.

IM 77C01E01-10E

3.8.4 Confirmation and Release of Demand Alarm State

[Procedure]

(1) To execute confirmation and release of demand alarm state, write data to the D

3-38

D Register

D0312

Reference No.

40312

H No.

0137

Description

Confirmation and release of demand alarm state

Effective Range

0: Normal state 1: Alarm state

Writing “0” during alarm state clears the alarm

[Example]

To execute confirmation of demand alarm state: For station number 01, use PC link communication (without checksum) and the word-basis

read (write) command as shown below:

<For read> [Command] [STX]01010WRDD0312,01[ETX][CR] [Response] [STX]0101OK0001[ETX][CR]

<For write> [Command] [STX]01010WWRD0312,01,0000[ETX][CR] [Response] [STX]0101OK[ETX][CR]

NOTE

Confirmation and release of demand alarm state can be set for the PR300 with demand measuring function.

IM 77C01E01-10E

4. PC Link Communication Protocol

4.1 Overview

The use of PC link communication enables the PR300 to communicate with a device such as a PC or FA-M3(PLC)'s UT link module. Such a device can be used in communication to read/write data from/to D registers which are internal registers of the PR300.

PLC

FA-M3 Model of UT link module: F3LC51-2N

RS-485 communication Maximum communication distance: 1200 m Maximum number of slave stations to be connected: 31

4-1

Figure 4.1 Example of Connection for PC Link Communication

Hereafter, PCs are generically called “higher-level devices.” In PC link communication, a higher-level device identifies each PR300 with a station

number of 01 to 99.

NOTE

• The PR300 has data (D register) the unit of which is two words. When 2-word data need to be written or read, writing or reading operations must be performed for the 2word data at the same time.

IM 77C01E01-10E

4.1.1 Configuration of Command

Commands sent from a higher-level device to the PR300 consist of the following elements.

4-2

Number

of Bytes

Element STX Station

12 2 1 3 2 11

number

(ST-NO)

(1) (2) (3) (4) (5) (7) (8) (9)(6)

CPU

number

Time to wait

for response

Command Data

Variable length

corresponding

to command

(1) STX (Start of Text)

This control code indicates the start of a command. The ASCII code is 02 in hexadecimal.

(2) Station Number (01 to 99)

Station numbers are used by the higher-level device to identify the PR300 at the communication destination. (These numbers are identification numbers specific to individual PR300.) P1: Broadcasting mode (See subsection 4.1.4, “Specifying Broadcast")

(3) CPU number

This number is fixed to ‘01.’ The ASCII codes are 30 and 31 in hexadecimal.

(4) Time to Wait for Response

This is fixed to ‘0’. The ASCII code is 30 in hexadecimal.

(5) Command (See section 4.2, “Command and Response”)

Specify a command to be issued from the higher-level device.

Checksum ETX CR

(6) Data Corresponding to Command

Specify an internal register (D register), number of data pieces, and others.

(7) Checksum

This is required if the protocol with checksum is selected for the RS-485 communication protocol parameter COMM.

It converts the ASCII codes of texts between the character next to STX and the character immediately before the checksum into hexadecimal values and adds them byte by byte. It then fetches the single lowermost byte of the added results as the checksum.

This column is required only for PC link communication with checksum. PC link communication without checksum does not require this 2-byte space of ASCII code.

[Example]

[STX]01010WRDD0001, 02䊐䊐 [ETX][CR] Add up the hexadecimal values of the ASCII codes of each text.

(‘0’ : 30, ‘1’ : 31, ‘W’ : 57, ‘R’ : 52, ‘D’ : 44, ‘,’ : 2C, ‘2’ : 32) 30+31+30+31+30+57+52+44+44+30+30+30+31+2C+30+32

Lowermost two digits of the added results as the checksum. [STX]01010WRDD0001,0272[ETX][CR]

IM 77C01E01-10E

(8) ETX (End of Text)

This control code indicates the end of a command string. The ASCII code is 03 in hexadecimal.

(9) CR (Carriage Return)

This control code indicates the end of a command. The ASCII code is 0D in hexadecimal.

NOTE

The control codes “STX”, “ETX”, and “CR” are essential for commands when you create a communication program for PC link communication. Omission of any of them or incorrect order of them results in communication failure.

4.1.2 Configuration of Response

Responses from the PR300 with respect to a command sent from the higher-level device consist of the elements shown below, which differ depending on the condition of communication; normal or failure.

4-3

1) Normal Communication

When communication completes normally, the PR300 returns a character string “OK” and data corresponding to a command.

No parameter data area for write command.

Number of Bytes

Element STX Station

number

(ST-NO)

CPU

number

Variable length12 22 211

OK Parameter data Checksum ETX CR

2) In the Event of Failure

If communication does not complete normally, the PR300 returns a character string “ER” and error code (EC1 and EC2). (See subsection 4.1.3, “Response Error Codes”.)

• No response is made in case of an error in station number specification or CPU number specification.

• If a PR300 cannot receive ETX in a command, response may not be made.

Note: As a countermeasure, provide a timeout process in the communication functions of the higher-level device or in

communication programs.

Number

of Bytes

Element STX ER EC1 EC2 Command Checksum ETX CRStation

12 22223 211

CPU

number

(ST-NO)

number

IM 77C01E01-10E

4.1.3 Response Error Codes

See Also

4.1.2, “Configuration of Response”, for the configuration of response in the event of error.

The error codes (EC1) and detailed error codes (EC2) of responses are as follows.

Table 4.1 List of Error Codes EC1

Error Code

Command error

Out of setpoint range

(when in writing operation)

Out of data count range

Monitor error

Parameter error

Checksum error

Internal buffer overflow

43 44 • The end-of-data or end-of-text character has not been received.

Character reception timeout

Meaning Cause(s)

• No command exists.

• Command not executable

• No register number exists.

•

A value other than hexadecimal values (0 to 9, A to F) has been specified in word

specification.

• The position of a start for a data load/save or other command is out of the address range.

• The specification of the number of words is out of the specified range.

• An attempt was made to execute monitoring without specifying the monitor

(WRS).

• An illegal parameter is set.

• The sum does not match the expected value.

• A data value greater than the specified was received.

4-4

Table 4.2 List of Detailed Error Codes EC2

Meaning

08 Parameter error

Out of setpoint range

Out of data count range

Parameter number where error occurred (HEX) This is the sequence number of a parameter that first resulted in an error when counted from the leading parameter.

e.g.:

[STX]01010WRW02D0043,3F80,A0044,0000[ETX][CR]

Parameter numbers 1 2 3 4 5

[STX]0101ER0304WRW[ETX][CR]

In this case, EC1=03 and EC2=04.

Detailed Error Code (EC2)Error Code (EC1)

↓

For error codes other than those noted as EC1, there is no EC2 meaning, and 0x00 is returned as a response.

IM 77C01E01-10E

4.1.4 Specifying Broadcast

The corresponding multiple PR300 perform the function to receive and process a command in which this station number is specified.

(1) Specify “P1” for the station number in the command to execute it. (2) This command works independently of station numbers of slave stations (01 to 99). (3) This command is applicable for writing only. (4) No response is returned from the PR300 when communication is performed using this

command.

4-5

RS-485 communication

Maximum communication distance: 1200 m Maximum number of slave stations to be connected: 31

Figure 4.2 Broadcasting

Broadcast data.

* No response from slave stations

[Example of Starting Optional Integrations]

Use PC link communication (without checksum) and the random write command as shown below:

[STX]P1010WRW01D0302,0000[ETX][CR]

D Register

D0302

Reference No.

40302

H No.

012D

Description

Optional integration start/stop (D0011 to D0014)

Effective Range

0: Stop 1: Start

IM 77C01E01-10E

4.2 Command and Response

The following shows the lists of commands available in PC link communication. The details of them are explained in the description of each command.

(1) Word-basis Access Commands

4-6

Command Description

WRD WWR WRR WRW

WRS

WRM

Word-basis read Word-basis write Word-basis, random read Word-basis, random write Specifies D registers to be monitored on a

word-by-word basis. Word-basis monitoring

(2) Information Commands

Command Description

INF6 INF7

Reads model, suffix codes, and version. Reads the maximum value of CPU.

Number of words to be handled

1 to 64 words 1 to 64 words 1 to 32 words 1 to 32 words

1 to 32 words

—

Number of units to be handled

1 1

IM 77C01E01-10E

WRD Reads D registers on a word-by-word basis

● Function

This function code reads a sequence of contiguous register information on a word-by-word basis by the specified number of words, starting with a specified register number.

• The number of words to be read at a time is 1 to 64.

• For the format of response in the event of failure, see subsection 4.1.2.

• The command shown below includes the checksum function. When performing

communication without the checksum, do not include the 2-byte checksum element in the command.

● Command/Response (for normal operation)

4-7

Number of

Bytes

Command

element

Number of

Bytes

Response

element

STX2Station

number

(ST-NO)

STX

Station

number

(ST-NO)

WRD

dddd14dddd2

number

Comma

space

…

Number

of words

(n)

ddddn

Checksum

Checksum1ETX1CR

ETX1CR

The response is returned in a 4-digit character string (0000 to FFFF) in hexadecimal. ddddn: read data of the specified number of words ddddn = character string in hexadecimal n = 1 to 64 words

● Example

Read the active energy (register symbol: kWh L and kWh H) of the PR300 at station number 01.

The register numbers for active energy are D0001 and D0002. [Command]

[STX]01010WRDD0001, 0272 [ETX] [CR]

The data of active energy (2 words) will be returned in response to the command above. [Response]

[STX]0101OK7840017D0B [ETX] [CR]

Note: To use the response data as the reading, reverse the order of the upper and lower words.

Hex 7840 017D → (reversed) → Hex 017D 7840 → Decimal 25000000

25000000 [kWh] in decimal.

See the Note below.

IM 77C01E01-10E

WWR Writes data into D registers on a word-by-word basis

● Function

This function code writes information into a sequence of contiguous registers on a word-byword basis by the specified number of words, starting with a specified register number.

• The number of words to be written at a time is 1 to 64.

• For the format of response in the event of failure, see subsection 4.1.2.

• The command shown below includes the checksum function. When performing

communication without the checksum, do not include the 2-byte checksum element in the command.

● Command/Response (for normal operation)

4-8

Number

of Bytes

Command

element

Command (continued)

dddd2

STX

…

Station

number

(ST-NO)

ddddn

Checksum1ETX1CR

WWR

number

Comma

or space

Number

of words

(n)

Comma

or space

Write information is specified in a 4-digit character string (0000 to FFFF) in hexadecimal.

ddddn: write data of the specified number of words ddddn = character string in hexadecimal n = 1 to 64 words

Number

of Bytes

Response

element

STX

Station

number

(ST-NO)

012OK

Checksum1ETX1CR

dddd1

● Example

Write the floating point data “00004120” into the VT ratio (register symbol: VT L and VT H) and CT ratio (register symbol: CT L and CT H) of the PR300 at station number 01. The register numbers for VT ratio are D0201 and D0202. The register numbers for CT ratio are D0203 and D0204.

[Command]

[STX]01010WWRD0201,04,0000412000004120C3[ETX][CR]

“OK” will be returned in response to the command above. [Response] [STX]0101OK5C[ETX][CR]

Note: To use the response data as the reading, reverse the order of the upper and lower words.

VT ratio: 4-byte floating-point hex data 0000 4120 → (reversed) → Hex 4120 0000 ⇒ Decimal 10 CT ratio: 4-byte floating-point hex data 0000 4120 → (reversed) → Hex 4120 0000 ⇒ Decimal 10

IM 77C01E01-10E

WRR Reads D registers on a word-by-word basis in random order

● Function

This function code reads the statuses of the individual registers, on a word-by-word basis, specified in a random order by the specified number of words.

• The number of words to be read at a time is 1 to 32.

• For the format of response in the event of failure, see subsection 4.1.2.

• The command shown below includes the checksum function. When performing

communication without the checksum, do not include the 2-byte checksum element in the command.

● Command/Response (for normal operation)

4-9

Number of Bytes

Command

element

Command (continued)

…

Number of Bytes

Response

element

STX2Station

number

STX2Station

number

(ST-NO)

Checksum

number

(ST-NO)

ETX1CR

WRR

dddd14dddd2

Number

of words

(n)

number

…

Comma

space

ddddn

Checksum

number

The response is returned in a 4-digit character string (0000 to FFFF) in hexadecimal. ddddn: read data of the specified number of words

ddddn = character string in hexadecimal n = 1 to 32 words

● Example

Comma

space

ETX1CR

Read the voltage-1 (register symbol: V1 L and V1 H) and current-1 (register symbol: A1 L and A1 H) of the PR300 at station number 01. The register numbers for voltage-1 are D0027 and D0028. The register numbers for current-1 are D0033 and D0034.

[Command] [STX]01010WRR04D0027,D0028,D0033,D003405[ETX][CR]

The data 800V for the voltage-1 and 50A for the current-1 will be returned in response to the command above.

[Response]

[STX]0101OK000044480000424882[ETX][CR]

800 [V] and 50 [A] in decimal. See the Note below.

Note: To use the response data as the reading, reverse the order of the upper and lower words.

Voltage-1: floating-point hex data 0000 4448→ (reversed) → Hex 4448 0000 ⇒ Decimal 800 Current-1: floating-point hex data 0000 4248→ (reversed) → Hex 4248 0000 ⇒ Decimal 50

IM 77C01E01-10E

4-10

WRW

Writes data into D registers on a word-by-word basis in random order

● Function

This function code writes register information specified for each register into the registers specified in a random order by the specified number of words.

• The number of words to be written at a time is 1 to 32.

• For the format of response in the event of failure, see subsection 4.1.2.

• The command shown below includes the checksum function. When performing

communication without the checksum, do not include the 2-byte checksum element in the command.

● Command/Response (for normal operation)

Number

of Bytes

Command

element

Command (continued)

number

STX2Station

Comma

space

number

(ST-NO)

dddd2

…

number

WRW

Comma

or space

Number

of words

(n)

ddddn

number

Checksum1ETX1CR

Comma

space

dddd1

Comma

space

Write information is specified in a 4-digit character string (0000 to FFFF) in hexadecimal. ddddn: repetition of register numbers and write information of the specified number

of words ddddn = character string in hexadecimal n = 1 to 32 words

Number

of Bytes

Response

element

STX2Station

number

(ST-NO)

012OK

Checksum1ETX1CR

● Example

Write 1 into the remote reset (register symbol: RMT RST) and active energy reset (register symbol: kWh RST) of the PR300 at station number 01. The register number for remote reset is D0400. The register number for active energy reset is D0353.

[Command] [STX]01010WRW02D0400,0001,D0353,000171[ETX][CR]

“OK” will be returned in response to the command above. [Response]

[STX]0101OK5C[ETX][CR]

IM 77C01E01-10E

4-11

WRS Specifies the D registers to be monitored on a word-by-word basis

● Function

This function code specifies the register numbers to be monitored on a word-by-word basis. Note that this command simply specifies the registers. Actual monitoring is performed by the WRM command after the register numbers are specified by this command.

If the volume of data is large and you wish to increase the communication rate, it is effective to use a combination of the WRS and WRM commands rather than the WRR command. If the power supply is turned off, the register numbers specified will be erased.

• The number of words to be specified at a time is 1 to 32.

• For the format of response in the event of failure, see subsection 4.1.2.

• The command shown below includes the checksum function. When performing

communication without the checksum, do not include the 2-byte checksum element in the command.

● Command/Response (for normal operation)

Number

of Bytes

Command

element

Command (continued)

…

Number

of Bytes

Response

element

STX2Station

number

STX2Station

number

(ST-NO)

Checksum

number

(ST-NO)

ETX1CR

012OK

Checksum

WRS

Number of words

(n)

ETX1CR

number

Comma

or space

number

● Example

Specify that the active power (register symbol: W L and W H) of the PR300 at station number 01 is to be monitored. (This command simply specifies the registers.) The register numbers for active power are D0021 and D0022.

[Command]

Comma

or space

[STX]01010WRS02D0021,D00228B[ETX][CR]

“OK” will be returned in response to the command above. [Response] [STX]0101OK5C[ETX][CR]

IM 77C01E01-10E

WRM Monitors the D registers on a word-by-word basis

● Function

This function code reads the information of the registers that have been specified in advance by the WRS command.

• Before executing this command, the WRS command must always be executed to specify which registers are to be monitored. If no register has been specified, error code 06 is returned.

• For the format of response in the event of failure, see subsection 4.1.2.

• The command shown below includes the checksum function. When performing

communication without the checksum, do not include the 2-byte checksum element in the command.

● Command/Response (for normal operation)

4-12

Number

of Bytes

Command

element

Number

of Bytes

Response

element

STX2Station

number

(ST-NO)

STX2Station

number

(ST-NO)

WRM

dddd14dddd2

Checksum1ETX1CR

…

ddddn

Checksum1ETX1CR

The response is returned in a 4-digit character string (0000 to FFFF) in hexadecimal. ddddn: read data of the number of words specified by the WRS command ddddn = character string in hexadecimal n = 1 to 32 words

● Example

Monitor the active power (register symbol: W L and W H) of the PR300 at station number

01. (This command reads the status of the register specified by the WRS command.) [Command] [STX]01010WRME8[ETX][CR]

The data 2500 will be returned in response to the command above. [Response]

[STX]0101OK4000451CF9[ETX][CR]

Note: To use the response data as the reading, reverse the order of the upper and lower words.

Active power: floating-point hex data 4000 451C→ (reversed) → Hex 451C 4000 ⇒ Decimal 2500

IM 77C01E01-10E

■ ■■ ■■

INF6 Reads the model, suffix codes, and version information

● Function

This function code reads the model, suffix codes, and version number of the PR300.

• For the format of response in the event of failure, see subsection 4.1.2.

● Command/Response (for normal operation)

4-13

Number

of Bytes

Command

element

Number

of Bytes

Response

element

Response (continued)

Start

specified for

write

refreshing*

The * mark indicates fields the FA-M3’s UT link module refers to.

Note 1: Model and suffix code information

STX2Station

Number of

registers

specified for

write

refreshing*

number

(ST-NO)

012OK number (ST-NO)

Checksum1ETX1CR

INF26

Checksum1ETX

Model code:

PR300✩★

(Note 1)

Note 2: Version number and revision number

Version and

revision

numbers

(Note 2)

PR300–✩★䊐䊐䊐–䊐䊐

Returns the currently selected phase and wire system

✩:

1: Single-phase two-wire system 2: Single-phase three-wire system 3: Three-phase three-wire system 4: Three-phase four-wire system 5: Three-phase four-wire system (2.5 element)

★: Returns the currently selected input range

1: 150 V/1 A 2: 150 V/5 A 3: 300 V/1 A 4: 300 V/5 A 5: 600 V/1 A 6: 600 V/5 A

(* ★ and ✩ are decided by the settings of the phase and wire system and the input range.) 䊐: Returns the suffix code as is

Example:

Suffix code: PR300-32333-6A-0; Selected phase and wire system: Single-phase three-wire system; and Selected input range: 300 V/5 A; then

PR300243336A

Not returned

Example: 0102 (version number + revision number)

Start

Number of

specified for

readout

refreshing*

registers

specified for

readout

refreshing*

● Example

To read the model, suffix code etc. of PR300 at station number 01: [Command] [STX]01010INF605[ETX][CR]

In response to this command, the following values will be returned: Phase and wire system: Single-phase three-wire system Rated input voltage/current: 300 V/5 A AC I/O function: Analog output and pulse output Communication function: Ethernet Optional measuring function: Demand measurement Phase indication format: R, S, and T indications

[Response] [STX]0101OKPR300243336R01020001002200010000E1[ETX][CR]

IM 77C01E01-10E

INF7 Reads the maximum value of CPU

● Function

This function code refurns the maximum value of CPU of a station in PC link communication.

• For the format of response in the event of failure, see subsection 4.1.2.

● Command/Response (for normal operation)

4-14

Number

of Bytes

Command

element

Number

of Bytes

Response

element

Note 1: The maximum value of CPU for power and energy meter is 1.

STX2Station

number

(ST-NO)

STX2Station

number

(ST-NO)

012OK

INF

maximum

value (Note1)

CPU

Checksum1ETX1CR

Checksum

ETX1CR

● Example

Read the maximum value of CPU number of the PR300 at station number 01. [Command] [STX]01010INF706[ETX][CR]

The data 1 will be returned in response to the command above. [Response] [STX]0101OK

18D[ETX][CR]

IM 77C01E01-10E

4.3 Communication with Higher-level Devices

Higher-level devices are those capable of using the PC link communication protocol.

4.3.1 Communication with FA-M3 (UT Link Module)

Communication with FA-M3 is achieved by simply connecting the PR300 to a UT link module using the PC link communication protocol. Set the communication conditions of the PR300 identical to those of the UT link module.

PLC

FA-M3 Model of UT link module: F3LC51-2N

RS-485 communication Maximum communication distance: 1200 m Maximum number of slave stations to be connected: 31

4-15

Figure 4.3 Communication with UT Link Module

The UT link module function has the following two modes, which allow you to communicate with FA-M3 without being aware of it. For more information, see the optionally available user's manual of UT Link Module (IM 34M6H25-01E).

1. Automatic mode This mode enables the instruments' fixed devices (those that cannot be specified by

the user) to be constantly refreshed by reading from them. The fixed devices are D0001 to D0022, and the read areas cannot be written to.

2. Manual mode This mode enables the instrument's devices (those that can be specified by the user)

to be constantly refreshed by reading from and/or writing to them.

See Also

The devices mentioned here are D registers. For more information on D registers, see Chapter 7.

IM 77C01E01-10E

FA-M3's UT Link Module Setup Procedure (Example)

This section explains the procedure for setting up the FA-M3's UT link module when the “Automatic mode” is used.

(1) Setting Up the UT Link Module Before following the procedure, always make sure that the FA-M3's UT link module is

turned off. Then, open the inner cover and follow the setup steps described below. Configure the DIP switch of the UT link module as shown below:

Switch No. Status Description

SW1 SW2, SW3 SW4 SW5 SW6 SW7 SW8

Set the Baud Rate switch to 9600 bps.

ON ON OFF OFF Checksum: none ON Termination character: yes (CR) ON Mode: Automatic mode OFF Not used.

Data length: 8 bits Parity: none (initial value: even) Stop bit: 1 bit

4-16

Set the Communication Mode switch to 7 (Normal).

(2) Setting Up the PR300 Set the communication conditions of the PR300 as shown below: For details on how to set the conditions, see the PR300 Power and Energy Meter Uuser's

Manual (electronic manual).

Parameter Description

Communication protocol Data length Parity Stop bit Baud rate

PC link communication (without checksum) 8 bits None 1 bit 9600 bps

(3) Turn on the FA-M3.

IM 77C01E01-10E

4.4 Sample Program

4.4.1 Example of BASIC Program for Send and Receive

4-17

This section shows an example of a command sending and response receiving program created with F-BASIC*

*1 PC/AT is the product of IBM Ltd. *2 F-BASIC is the product of Fujitsu Ltd.

for PC/AT*1 (or compatible machines).

Example of the Program Created Using F-BASIC Version 6.3

Communication Conditions Baud rate: 9600bps

Parity: None Data length: 8 bits Stop bit: 1 bit Protocol: PC link (without checksum)

STX$=CHR$(2) ‘Define ETX$=CHR$(3) ‘Define CR$=CHR$(13) ‘Define LF$=chr$(10) ‘Define RCVCHR$=”” ‘

Initialize receive character string STOPFLAG=0 ‘Initialize end flag ‘

SEND$=STX$+”01010WRDD0001,02"+ETX$ ‘

Create character string for send ‘

BAUD 0,9600 ‘Set a communication baud rate open “COM0:(F8N1N7)” as #1 ‘Open a communication port

‘

interval 5 ‘Set timeout timer on com(0) gosub *RECEIVECHR ‘

Specify interruption processing

during receiving

on interval gosub *TIMEOUT ‘

Specify interruption processing

at timeout

‘

print #1,SEND$ ‘Send com(0) on ‘

Permit interruption during receiving

interval on ‘Start timer

‘

while STOPFLAG=0 ‘

Wait for receive end or timeout

waiti wend

‘

com(0) off ‘

Permit interruption during receiving

close #1 ‘Close the port

‘

print “>”+SEND$ ‘Display sent character string

on screen

print “<“+RCVCHR$ ‘Display received character

string on screen end ‘

IM 77C01E01-10E

‘=== Subroutine === *RECEIVECHR ‘Interruption processing during

receiving interval off ‘Start timer RCVCHR$=RCVCHR$+input$(lof(#1),#1) ‘Fetch character string

from receive buffer. END$=mid$(RCVCHR$,len(RCVCHR$),1) select case END$

case LF$ ‘Echo-back-capable RCVCHR$=”” ‘

Initialize receive character string case CR$ ‘Receiving end flag STOPFLAG=1 ‘Set receiving end flag case else

end select

interval on ‘Start timer return ‘ *TIMEOUT ‘Timeout processing

STOPFLAG=1 ‘Set timeout flag

RCVCHR$=”Time out ! (5 sec)”+CR$

‘

Character string for display

on screen “Time out ! (5 sec)

return

4-18

”

IM 77C01E01-10E

5-1

5. Modbus/RTU and ASCII Communication Protocols

5.1 Overview

The use of Modbus communication enables the PR300 to communicate with a device such as a PC or PLC (sequencer). Such a device can be used in communication to read/write data from/to D registers which are internal registers of the PR300.

Hereafter, PCs are generically called “higher-level devices.”

Higher-level device

RS-485 communication Maximum communication distance: 1200 m Maximum number of slave stations to be connected: 31

Figure 5.1 Example of Connection for Modbus Communication

See Also

Chapter 7 for information on the D registers.

IM 77C01E01-10E

For Modbus communication with the PR300, we provide the ASCII mode and RTU mode (binary system) for the transmission mode.

Table 5.1 ASCII and RTU Modes

Item ASCII Mode RTU Mode

Number of data bits 7 bits (ASCII) 8 bits (binary) Message start mark Message end mark Message length Data time intervals 1 second or less Between frames: 3.5 characters Error detection

*1: When message length in the RTU mode is assumed to be “N”, message length in ASCII mode is “2N+1”. *2: LF is a synchronization character indicating that the PR300 is ready to accept the next signal. In the RTU mode,

synchronization is achieved during the time interval between characters. If there is a period of time equivalent to 3.5 characters before the next character is received, the message being received next is recognized as a new frame.

(*1)

: (colon) None CR+LF 2N+1 N

Longitudinal redundancy check: LRC Cyclic redundancy check: CRC-16

(*2)

None

In Modbus communication, a higher-level device identifies each PR300 with a station number of 01 to 99.

NOTE

5-2

• The PR300 has data (D register) the unit of which is two words. When 2-word data need to be written or read, writing or reading operations must be performed for the 2word data at the same time.

• Even if data written to the D register is out of the effective range, a normal response is returned.

IM 77C01E01-10E

5.1.1 Configuration of Message

Messages sent from the higher-level device to the PR300 consist of the following elements.

5-3

Element

Number of bytes in RTU mode

Number of bytes in ASCII mode

Start of

Message Mark

None

1224n

(1) (3) (4) (5)(2) (6)

Station Number (ST-NO)

112n

Function

Code

Data Error Check End of

(variable)

(1) Start of Message Mark

This mark indicates the start of a message. Note that only ASCII mode requires a colon (:).

(2) Station Number (01 to 99)

Station numbers are used by the higher-level device to identify the PR300 at the communication destination. (These numbers are identification numbers specific to individual PR300, which are expressed in hexadecimal in the message.)

00: Broadcasting mode (See subsection 5.1.5, “Specifying Broadcast”)

(3) Function Code (See section 5.2, “Message and Response”)

This element specifies a command (function code) from the higher-level device.

Message Mark

None

(4) Data

This element specifies D register numbers, the number of D registers, parameter values, or others in accordance with the function code. (It is expressed in hexadecimal in the message.)

(5) Error Check

In RTU mode: Carried out by the cyclic redundancy check (CRC-16) system. In ASCII mode: Carried out by the longitudinal redundancy check (LRC) system.

(6) End of Message Mark

This mark indicates the end of a message. Note that only ASCII mode requires CR + LF.

IM 77C01E01-10E

5.1.2 Specifying D Registers

Specification of D registers using commercially available SCADA or other software and specification of D registers for messages used in a customer-created communication program are different. Take note of this.

For a customer-created communication program, specify a value in hexadecimal that is obtained by subtracting 40001 from a reference number.

Example: Specifying “D0043”

For messages in the customer-created communication program, specify “002A,” the hexadecimal number of value 42 obtained by subtracting 40001 from the reference number.

5.1.3 Checking Errors

Modbus communication has two modes, i.e., the ASCII mode which is communication based on ASCII characters and the RTU mode which is binary code communication. These modes use different error-checking methods.

5-4

■ ASCII Mode

In the ASCII mode, errors are checked by means of an LRC longitudinal redundancy check.

The LRC value is the two's complement of the sum obtained by adding up data byte by byte, from the station number to the last data item, excluding ‘:’, ‘CR’ and ‘LF.’ Ignore the carry that may occur at the upper digit when adding up the data.

Example:

The method of calculating the LRC for the [:]110300C80004[LRC][CR][LF] command for reading a series of four D registers of the device at station number 17, starting with the D00201 (VT ratio) register, is as follows:

[1] Station number 17 is 11 in hexadecimal.

Change the data to byte-by-byte hex data ⇒ 11,03,00,C8,00,04. (In the Modbus/ASCII message, this data is represented by the ASCII code as two bytes, i.e., 31 and 31 in hexadecimal.)

[2] Add up the byte-by-byte hex data on a byte-by-byte basis.

⇒ 11 + 03 + 00 + C8 + 00 + 04 = E0

[3] Find the two's complement of the lower one byte of the data thus added up ⇒ 20

11100000 (0xE0) → 00011111 (complement) + 1 = 00100000 (20)

IM 77C01E01-10E

■ RTU Mode

In the RTU mode, errors are checked by means of a CRC-16 cyclic redundancy check. The CRC-16 value is the 16-bit remainder when the value obtained by concatenating the 8 bits of all blocks (from the station number to the last data item) of a message, excluding the start bit, stop bit and parity bit, is divided by a predetermined 17-bit binary number.

● Example of CRC-16 Calculation

When executing function code 03 (reads data from multiple D registers) to read the status from the slave at station number 11 “0B”, send the 0B03002A0004 command.

[1] The initial value is FFFF. Find the XOR value of this initial value and the first character

(= station number 11).

[2] Refer to the lower byte of the result of executing the function code (or the upper byte, if

the result is regarded as a block of text). From the table, obtain the value corresponding to that byte. Since the result is “F4” in this example, you refer to the 244th value in the table and obtain “8701”.

[3] Find the XOR value of the upper byte of the XOR operation in step [1] and the result of

step [2]. This value is the first character of the CRC-16 calculation.

[4] Using the result of step [3] (remainder) as the next initial value, make the same calcu-

lation to evaluate the second character (function code 03).

5-5

Initial value FF FF Station number 0B

--------XOR FF F4 Reference to table

XOR 87 FE Function code 03

XOR 87 FD Reference to table

XOR

•

XOR E5 9E Last character 04

-------XOR E5 9A Reference to table

Resulting error 6B 6

6B 80

--------

87 01

--------

81 C1

------- 81 46

•

Convert the hex value to a decimal value, find the corresponding number in Table 5.2, and substitute the number into the formula. In the example shown on the left, hex value “F4” is converted to decimal value 244. From Table 5.2, the number corresponding to 244 proves to be “8701”. This number is substituted into the formula.

[5] Repeat steps [1] to [4] to perform the calculation up to the last character string 04. [6] Reverse the order of the upper and lower bytes of 6B65 and append 656B to the end

of the character string as the error code. 0B03002A0004

First reverse the order of the upper and lower bytes of the calculated result, then compare the value with the received data or store the value in the transmission buffer.

* Numbers in quotation marks are hexadecimal.

656B

IM 77C01E01-10E

Table 5.2 Results of Performing CRC on 0th to 255th Values at “A001”

Number

0 1 2 3 4 5 6 7

Result

0000 C0C1 C181 0140 C301 03C0 0280 C241

Number

8 9 10 11 12 13 14 15

Result

C601 06C0 0780 C741 0500 C5C1 C481 0440

Number

16 17 18 19 20 21 22 23

Result

CC01 0CC0 0D80 CD41 0F00 CFC1 CE81 0E40

Number

24 25 26 27 28 29 30 31

Result

0A00 CAC1 CB81 0B40 C901 09C0 0880 C841

Number

32 33 34 35 36 37 38 39

Result

D801 18C0 1980 D941 1B00 DBC1 DA81 1A40

Number

40 41 42 43 44 45 46 47

Result

1E00 DEC1 DF81 1F40 DD01 1DC0 1C80 DC41

Number

48 49 50 51 52 53 54 55

Result

1400 D4C1 D581 1540 D701 17C0 1680 D641

Number

56 57 58 59 60 61 62 63

Result

D201 12C0 1380 D341 1100 D1C1 D081 1040

Number

64 65 66 67 68 69 70 71

Result

F001 30C0 3180 F141 3300 F3C1 F281 3240

Number

72 73 74 75 76 77 78 79

Result

3600 F6C1 F781 3740 F501 35C0 3480 F441

Number

80 81 82 83 84 85 86 87

Result

3C00 FCC1 FD81 3D40 FF01 3FC0 3E80 FE41

Number

88 89 90 91 92 93 94 95

Result

FA01 3AC0 3B80 FB41 3900 F9C1 F881 3840

Number

Result

Number

Result

Number

Result

Number

Result

Number

Result

Number

Result

Number

Result

Number

Result

Number

Result

Number

Result

Number

Result

Number

Result

Number

Result

Number

Result

Number

Result

Number

Result

Number

Result

Number

Result

Number

Result

Number

Result

96 97 98 99 100 101 102 103 2800 E8C1 E981 2940 EB01 2BC0 2A80 EA41 104 105 106 107 108 109 110 111 EE01 2EC0 2F80 EF41 2D00 EDC1 EC81 2C40 112 113 114 115 116 117 118 119 E401 24C0 2580 E541 2700 E7C1 E681 2640

120 121 122 123 124 125 126 127 2200 E2C1 E381 2340 E101 21C0 2080 E041 128 129 130 131 132 133 134 135 A001 60C0 6180 A141 6300 A3C1 A281 6240 136 137 138 139 140 141 142 143 6600 A6C1 A781 6740 A501 65C0 6480 A441 144 145 146 147 148 149 150 151 6C00 ACC1 AD81 6D40 AF01 6FC0 6E80 AE41 152 153 154 155 156 157 158 159 AA01 6AC0 6B80 AB41 6900 A9C1 A881 6840 160 161 162 163 164 165 166 167 7800 B8C1 B981 7940 BB01 7BC0 7A80 BA41 168 169 170 171 172 173 174 175 BE01 7EC0 7F80 BF41 7D00 BDC1 BC81 7C40 176 177 178 179 180 181 182 183 B401 74C0 7580 B541 7700 B7C1 B681 7640 184 185 186 187 188 189 190 191 7200 B2C1 B381 7340 B101 71C0 7080 B041 192 193 194 195 196 197 198 199 5000 90C1 9181 5140 9301 53C0 5280 9241 200 201 202 203 204 205 206 207 9601 56C0 5780 9741 5500 95C1 9481 5440 208 209 210 211 212 213 214 215 9C01 5CC0 5D80 9D41 5F00 9FC1 9E81 5E40 216 217 218 219 220 221 222 223 5A00 9AC1 9B81 5B40 9901 59C0 5880 9841 224 225 226 227 228 229 230 231 8801 48C0 4980 8941 4B00 8BC1 8A81 4A40 232 233 234 235 236 237 238 239 4E00 8EC1 8F81 4F40 8D01 4DC0 4C80 8C41 240 241 242 243 244 245 246 247 4400 84C1 8581 4540 8701 47C0 4680 8641 248 249 250 251 252 253 254 255 8201 42C0 4380 8341 4100 81C1 8081 4040

5-6

IM 77C01E01-10E

5.1.4 Configuration of Response

The PR300 receives a command message from the higher-level device. If the received command message is found to be normal and directed at the station number of the PR300 itself, the PR300 concludes the content of the message to be normal. Thus, the PR300 enters the phase of executing message processing, deciphers the content of the command message, and processes with the message.

The PR300 does not execute message processing, however, if the received command message is found to be abnormal. In that case, the PR300 either ignores the received message or creates a response message telling the received message is erroneous.

After receiving a normal command message and executing a given process, the PR300 creates and sends a response message to which error check data appropriate for the command function code of the higher-level device is added.

■ Responses to Normal Messages

For a loop back function or a function for writing to a single register, the PR300 returns the received command message as a response message.

For a function for writing to multiple D registers, the PR300 returns part of the received command message as the response message.

For a readout function, the PR300 adds the read data to the ends of the station number and function code of the received command message, and returns the message as the response message.

5-7

IM 77C01E01-10E

■ Responses to Abnormal Messages

If there is any failure other than transmission errors, the PR300 returns the following response message without executing any process:

5-8

1 2

Function

Code

(*1)

1 2

Error Code

1 2

Error

Check

2 2

Element

Number of bytes in RTU mode Number of bytes in ASCII mode

*1: The function code entered here is the function code (in hex) plus 80 (in hex).

Start of

Message

Mark (:)

None

Station Number (ST-NO)

The following table summarizes details on the error codes.

Error Code

01 02 Abnormal D register number 03

Funcation code error

Abnormal number of D registers

Meaning

Cause

Function code does not exist. D register number out of the range is specified. Number of D registers out of the range is specified.

The PR300 does not regard it as an error even if there is any unused register among those with consecutive register numbers specified by a readout function; rather, the PR300 returns a value of 0 in this case.

The PR300 returns the error code 02 or 03 if the specified consecutive registers are made to fall outside the given range by the number of registers specified, even though the Dregister start number was initially within the range. (Depend on the function code.)

■ Cases when There Are No Responses to Transmitted Messages

[CR][LF]

None

• A transmission error (overrun, framing, parity, LRC or CRC-16 error) is encountered.

• The station number in the command message is wrong.

• The interval between data composing a message is longer than 2 seconds.

• The station number is “00” (broadcast specification).

• The receiving buffer has overflowed.

Note: As a measure against the abovementioned problems, add a time-out process to the communication function or

program of the higher-level device.

IM 77C01E01-10E

5.1.5 Specifying Broadcast

The corresponding multiple PR300s perform the function to receive and process a command in which this station number is specified.

(1) Specify “00” for the station number in the command to execute it. (2) This command works independently of station numbers of slave stations. (3) This command is applicable for writing only. (4) No response is returned from the PR300 when communication is performed using this

command.

5-9

Higher-level device

RS-485 communication

Maximum communication distance: 1200 m Maximum number of slave stations to be connected: 31

Figure 5.2 Broadcasting

Broadcast data.

* No response from slave stations

[Example]

Write 0001 into the D0400 (remote reset) using broadcast command.

[Message] [:]0006018F000168[CR][LF]

“00”: broadcast addressing, “06”: function code 06, “018F”: D register number 400, “0001”: data 0001, “68”: error check

* Numbers in quotation marks are hexadecimal.

No response is returned to the above message.

D-Reg No.

D0400 40400 018F Remote reset

Ref No. H No. Description Effective Range

If other than 1: Invalid If 1: PR300 is reset

NOTE

• Even when remote reset is executed, active energy, reactive energy, and apparent energy data as well as set parameter values are retained.

IM 77C01E01-10E

5.2 Message and Response

Function codes are command words used by the higher-level device to obtain the D registers information of PR300.

Table 5.3 Function Codes

Code Function

Reads data from multiple D registers.

Writes data into D register.

Performs loop back test.

Writes data into multiple D registers.

Capable of reading data from a maximum of 64 successive D registers between D0001 and D0400.

Capable of writing data into one D register between D0001 and D0400.

Used when checking communication wiring.

Capable of writing data into a maximum of 32 successive registers between D0001 and D0400.

• The write function codes cannot be written into read-only or user-prohibited D registers.

• Broadcast addressing is possible with function codes 06 and 16 only. (Also in this case, cannot be written into read-only or user-prohibited D registers.)

Description

5-10

IM 77C01E01-10E

03 Reads data from multiple D registers

● Function

This function code reads the contents of successive D registers by the specified number starting with a specified D registers number.

• The maximum number of D registers to be read at a time is 64.

• For the format of responses in the event of failure, see subsection 5.1.4.

● Message (for normal operation)

5-11

Element

Number of bytes

in RTU mode

Number of bytes

in ASCII mode

Message (continued)

Error

Check

End of Message Mark

Start of

Message

Mark (:)

None

(CR + LF)

None

Station Number (ST-NO)

● Response (for normal operation)

Element

Number of bytes

in RTU mode

Number of bytes

in ASCII mode

Response (continued)

Contents of

D Register

Start of

Message

Mark (:)

None

Error

Check

Station Number (ST-NO)

End of Message Mark

Function

Code

(03)

(CR + LF)

None

Function Code

(03)

Byte

Count

D-Register

Start Number

Contents of

D Register

Number of

D Registers

...

● Example (ASCII mode)

Read a series of four D registers starting with the D0201 (VT ratio and CT ratio) at station number 11.

[Message] [:]0B0300C8000426[CR][LF] “0B”:station number 11, “03”: function code 03, “00C8”: D register start number 201, “0004”: number of D registers 4, and “26”: error check

* Numbers in quotation marks are hexadecimal.

The following response will be returned to the message above. [Response] [:]0B030800003F8000003F806C[CR][LF]

* The VT ratio and CT ratio data are floating point values. The combined value of D0201 and

D0202, 00003F80, represents 1. That of D0203 and D0204, which is also 00003F80, represents 1 as well (the upper four digits, 3F80, and the lower four digits, 0000, are reversed).

* The floating point value of 3F800000 is the decimal equivalent of 1.

IM 77C01E01-10E

06 Writes data into D register

● Function

This function code writes data into a specified D registers number.

• The maximum number of D registers to be written into at a time is 1.

• For the format of response in the event of failure, see subsection 5.1.4.

• Broadcast addressing is possible (by setting “00” to the station number).

● Message (for normal operation)

5-12

Element

Number of bytes

in RTU mode

Number of bytes

in ASCII mode

Message (continued)

Write Data

(Upper Digit)

(Lower Digit)

Start of

Message

Mark (:)

None

Write Data

Station Number (ST-NO)

Error

Check

End of Message Mark

● Response (for normal operation)

Element

Number of bytes

in RTU mode

Number of bytes

in ASCII mode

Response (continued)

Write Data

(Upper Digit)

(Lower Digit)

Start of

Message

Mark (:)

None

Write Data

Station Number (ST-NO)

Error

Check

End of Message Mark

Function Code

(CR + LF)

None

Function Code

(CR + LF)

None

(06)

D-Register

Number

(Upper Digit)

D-Register

Number

(Upper Digit)

D-Register

Number

(Lower Digit)

D-Register

Number

(Lower Digit)

● Example (ASCII mode)

Write 0001 into the D0302 (optional integration start/stop) at station number 11. [Message] [:]0B06012D0001C0[CR][LF] “0B”: station number 11, “06”: function code 06, “012D”: D register number 302, “0001”:

data 0001, and “C0”: error check

* Numbers in quotation marks are hexadecimal.

The following response will be returned to the message above. [Response] [:]0B06012D0001C0[CR][LF]

The frame same as the message is returned.

IM 77C01E01-10E

08 Performs loop back test

● Function

This function code is used to check connection for communication.

• For the format of response in the event of failure, see subsection 5.1.4.

• The “00” shown below (marked with an asterisk *) are fixed.

• Any value can be selected for transmit data.

● Message (for normal operation)

5-13

Element

Number of bytes

in RTU mode

Number of bytes

in ASCII mode

Message (continued)

Error

Check

End of Message Mark

Start of

Message

Mark (:)

None

(CR + LF)

None

Station Number (ST-NO)

● Response (for normal operation)

Element

Number of bytes

in RTU mode

Number of bytes

in ASCII mode

Response (continued)

Error

Check

End of Message Mark

Start of

Message

Mark (:)

None

(CR + LF)

None

Station Number (ST-NO)

Function Code

(08)

Function Code

(08)

0000

Transmit Data

(Arbitrary)

Same as

Transmit Data

● Diagnostic Codes

Diagnostic Code

0000

Command message return

Meaning

Data

Arbitrary

● Example (ASCII mode)

Send data 0000 (fixed) and transmit data 04D2 (arbitrary) to the station number 11 to check the connection for communication.

[Message] [:]0B08000004D217[CR][LF]

When the connection is normal, the following response same as the command will be returned. [Response] [:]0B08000004D217[CR][LF]

IM 77C01E01-10E

16 Writes data into multiple D registers

● Function

This function code writes data into successive D registers by the number starting with a specified D registers number.

• The maximum number of D registers to be written into at a time is 32.

• For the format of response in the event of failure, see subsection 5.1.4.

• Broadcast addressing is possible (by setting “00” to the station number).

No response is returned when using the broadcast addressing.

● Message (for normal operation)

5-14

Element

Number of bytes

in RTU mode

Number of bytes

in ASCII mode

Massage (continued)

Number of

D Registers

(Upper Digit)

Start of

Message

Mark (:)

None

Number of

D Registers

(Lower Digit)

Byte

Count

Station Number (ST-NO)

(Upper Digit)

● Response (for normal operation)

Element

Number of bytes

in RTU mode

Number of bytes

in ASCII mode

Response (continued)

Number of

D Registers

(Upper Digit)

Start of

Message

Mark (:)

None

Number of

D Registers

(Lower Digit)

Station Number (ST-NO)

Error Check

Function

Code

(10)

End of Message

Function Code

Data

Start Number

(Upper Digit)

Mark

(CR + LF)

None

(10)

Data

(Lower Digit)

D-Register

D-Register Start

Number

(Upper Digit)

…

D-Register

Start Number

(Lower Digit)

D-Register Start

Error

Check

Number

(Lower Digit)

End of Message

Mark

(CR + LF)

None

IM 77C01E01-10E

● Example (ASCII mode)

Write 10 into a series of four D registers starting with the D0201 (VT ratio and CT ratio) at station number 11. [Message] [:]0B1000C800004120000041204F[CR][LF]

“0B”: station number 11, “10”: function code 16, “00C8”: D register start number 201, “0004”: number of D registers 4, “08”: byte count (number of D registers × 2), “0000”: VT ratio lower two bytes, “4120”: VT ratio upper two bytes, “0000”: CT ratio lower two bytes, “4120”: CT ratio upper two bytes and “4F”: error check

* Numbers in quotation marks are hexadecimal.

The following response will be returned to the message above. [Response]

[:]0B1000C8000419[CR][LF]

Write 1 into the D0207(setup change status) to activate the writing into the VT ratio and CT ratio. [:]0B0600CE000120[CR][LF]

“0B”: station number 11, “06”: function code 06, “00CE”: D register start number 207, “0001”: writing data 0001, and “20”: error check

5-15

* Numbers in quotation marks are hexadecimal.

IM 77C01E01-10E

6. Modbus/TCP Communication Protocol

6.1 Overview

Modbus/TCP is one of the protocol used to communicate with devices such as PCs or PLCs (sequencers) using the TCP/IP protocol via Ethernet and other networks.

This communication protocol is used to perform read/write operations with the D registers in the PR300 and exchange data with connected devices.

The PR300 can be connected to IEEE802.3-compliant networks (10BASE-T/ 100BASE-TX). Generally, the Modbus/TCP protocol communicates through port 502.

In addition, the PR300 operates as Ethernet-serial gateway. A higher-level device can exchange data with other serial communication devices using the Modbus/TCP protocol via the PR300.

Higher-level devices (PC etc.)

6-1

Application Layer Transport Layer Network Layer Data link Layer Physical Layer

Figure 6.1 Network Layer

Modbus/TCP TCP IP ETHERNET 10BASE-T/100BASE-TX

IM 77C01E01-10E

(Example)

Higher-level device IP address [192.168.1.1] (arbitrary)

Maximum distance between hub and module: 100 m Maximum number of hubs connectable in cascade configuration: 4 levels for 10BASE-T 2 levels for 100BASE-TX

PR300 as Ethernet-serial gateway function

HUB

LAN connection

6-2

Station number 01 (fixed) IP address [192.168.1.2] (arbitrary)

RS-485 connection

Station number 02

(arbitrary)

Station number 01 (fixed) IP address [192.168.1.3] (arbitrary)

Station number 03

(arbitrary)

Station number 01 (fixed) IP address [192.168.1.4] (arbitrary)

Figure 6.2 Example of Connection for Modbus/TCP Communication

See Also

Chapter 7 for information on the D registers.

Station number 01 (fixed) IP address [192.168.1.5] (arbitrary)

IM 77C01E01-10E

6.2 TCP/IP Communication

Modbus/TCP communicates with other devices, following the procedure below, through the TCP/IP socket interface.

Ethernet

PR300 with Ethernet

communication function

6-3

Initial Setup

socket()

connect()

send()

recv()

close()

Figure 6.3 TCP/IP Communication

Open connection

Command

Response

Terminate connection

Initial Setup

socket()

bind()

listen()

accept()

recv()

send()

close()

NOTE

If no request is received from the higher-level device for more than 60 seconds after establishing a connection, the PR300 will automatically terminate the connection.

IM 77C01E01-10E

6.3 Network Frame Structure

The Modbus/TCP frame structure is as follows:

MODBUS TCP/IP ADU

MBAP Header Function code Data

PDU

MBAP Header (Modbus Application Protocol Header) : Header used to identify the Modbus/TCP protocol PDU: simple Protocol Data Unit

6.3.1 MBAP Header Structure

The MBAP Header (Modbus Application Protocol Header) consists of the following seven bytes.

Byte No01234 5 6

6-4

Description

Transaction ID: Set any value for identifying the transaction. The PR300 returns a value received from a higher-level device

Protocol ID: Specify “0” for the Modbus/TCP protocol. Number of bytes: Number of bytes after the unit ID (byte number 6) Unit ID: For the communication with the PR300 itself, specify “01” for the higher-level device. The PR300 returns “01” as a

Transaction ID

as a response.

response. For the communication with the device connected to the RS-485 communication terminals of the PR300 using the Ethernet-serial gateway function, specify its station number (02 to 99). The device returns the same value as a response.

6.3.2 PDU Structure

The PDU (simple Protocol Data Unit) consists of the following n bytes.

Byte No 0 1 to (n-1)

Description

Function code: Specify a command (function code) from a higher-level device. Data: Specify D register numbers, number of D registers, parameter values, or others in accordance with the function code.

(expressed in hexadecimal in the request)

Function code

Protocol ID Unit IDNumber of bytes

Data

IM 77C01E01-10E

6.4 Communication with Higher-level Devices

6.4.1 List of Function Codes

The codes in the following list are command words higher-level devices use to acquire information from the internal registers (D registers) of the PR300.

6-5

Code Function

Reads data from multiple D registers.

Writes data into D register.

Performs loop back test.

Writes data into multiple D registers.

The write function codes cannot be written into read-only or use-prohibited D registers.

6.4.2 Specifying D Registers

Follow the procedures below to specify a D register from a higher-level device: (1) If using commercially available SCADA or other software, specify the Ref No. indicated

in Chapter 7, “Functions and Usage of D Registers.”

(2) For customer-created communication programs, specify the H No. indicated in Chap-

ter 7, “Functions and Usage of D Registers.”

Example: To specify D0301 as the integration start/stop, *Specify Ref. No. 40301 for a request using commercially available SCADA or other

software.

Description

Capable of reading data from a maximum of 64 successive D registers between D0001 and D0400.

Capable of writing data to one D register between D0001 and D0400.

Used when checking communication wiring.

Capable of writing data into a maximum of 32 successive register between D0001 and D0400.

*Specify H No. “012C” for a request using customer-created communication program.

IM 77C01E01-10E

6.4.3 Request and Response

03 Reads data from multiple D registers

● Function

This function code reads the contents of successive D registers by the specified number starting with a specified D registers number.

• The maximum number of D registers to be read at a time is 64.

• For the format of responses in the event of failure, see subsection 6.4.4.

● Request (for nomal operation): Reading data from n registers

6-6

Element

Number of bytes

Command

element

Hex value

MBAP Header

22 2 2211

Transaction ID

Arbitrary 0000 0006 n

Protocol ID

Number of

bytes

Unit ID

01 to 99

Function

code

start number

PDU

Number of

registers

● Response (for normal operation)

Element

Number of bytes

Command

element

Hex value

22 2 2 2111

Transaction ID

Arbitrary 0000 2n+3 03 2n

MBAP Header

Protocol ID

Number of

bytes

Unit ID

01 to 99

Function

code

Byte

count

Contents of

PDU

● ● ● ●

● Example

Read a series of four D registers starting with D0201 (VT ratio and CT ratio) at station number 01.

[Request] 000100000006010300C80004

(1) (2) (3) (4) (5) (6) (7)

Contents of

(1) “0001”: Arbitrary 2-byte data (2) “0000”: Protocol ID=0000 (fixed) (3) “0006”: Number of bytes (4) “01”: Unit ID = 01 indicating PR300 (5) “03”: Function code 03 (6) “00C8”: D register start number 201 (7) “0004”: Number of D registers = 4

The following response will be returned to the request above: [Response] 00010000000B01030800003F8000003F80

* The VT ratio and CT ratio data are floating point values. The combined value of D0201 and D0202, 00003F80, represents 1. That of D0203 and D0204, which is also 00003F80, represents 1 as well (the upper four digits, 3F80, and the lower four digits, 0000, are reversed).

* The floating point value of 3F800000 is the decimal equivalent of 1.

(1) (2) (3) (4) (5) (6)

D0201 and D0202

D0203 and D0204

(1) “0001”: The arbitrary 2-byte data in the request (2) “0000”: Protocol ID = 0000 (fixed) (3) “000B”: Number of bytes (4) “01”: Unit ID = 01 indicating PR300 (5) “03”: Function code 03 (6) “08”: Byte count

* Numbers in quotation marks are hexadecimal.

IM 77C01E01-10E

Yokogawa PR300 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Introduction

Documentation Conventions

Notices

CONTENTS

1. Communications Overview

1.1 RS-485 Communication Specifications

1.2 Ethernet Communication Specifications

2. Setup

2.1 Setup Procedure

2.1.1 Procedure for RS-485 Communication

2.1.2 Procedure for Ethernet Communication

2.1.3 Procedure for Ethernet-Serial Gateway Function

2.2 Setting Communication Conditions

2.2.1 Conditions for RS-485 Communication

2.2.2 Conditions for Ethernet Communication

2.2.3 Conditions for Ethernet-Serial Gateway Function

2.3 Wiring for Communication

2.3.1 Wiring for RS-485 Communication

2.3.2 Wiring for Ethernet Communication

2.3.3 Wiring for RS-485 Communication for Ethernet-Serial Gateway Function

3. Procedures for Setting PR300 Functions

3.1 Basic Setting

3.1.1 Setting of VT Ratio

3.1.2 Setting of CT Ratio

3.1.3 Setting of Integrated Low-cut Power

3.2 Setting Pulse Output

3.2.1 Selection of Measurement Item for Pulse Output

3.2.2 Pulse Unit

3.2.3 ON Pulse Width

3.3 Setting Analog Output

3.3.1 Selection of Measurement Item for Analog Output

3.3.2 Upper/Lower Limits of Scaling

3.4 Demand Setting

3.4.1 Demand Power/Current

3.4.2 Demand Period

3.4.3 Demand Alarm Mask Time

3.4.4 Demand Power Alarm Point

3.4.5 Demand Current Alarm Point

3.4.6 Demand Alarm Release Function

3.5 Communication Setting

3.5.1 Protocol

3.5.2 Baud Rate

3.5.3 Parity

3.5.4 Stop Bit

3.5.5 Data Length

3.5.6 Station Number

3.5.7 IP Address (for Ethernet communication)

3.5.8 Subnet Mask (for Ethernet communication)

3.5.9 Default Gateway (for Ethernet communication)

3.5.10 Port Number (for Ethernet communication)

3.6 Writing Energy Values

3.6.1 Active Energy

3.6.2 Regenerative Energy

3.6.3 LEAD Reactive Energy

3.6.4 LAG Reactive Energy

3.6.5 Apparent Energy

3.7 Executing Reset Operations

3.7.1 Remote Reset

3.7.2 Maximum/Minimum Values Reset

3.7.3 Energy Value All-Reset

3.7.4 Active Energy Reset

3.7.5 Regenerative Energy Reset

3.7.6 Reactive Energy Reset

3.7.7 Apparent Energy Reset

3.8 Setting Control States

3.8.1 Integration Start/Stop

3.8.2 Optional Integration Start/Stop

3.8.3 Demand Measurement Start/Stop

3.8.4 Confirmation and Release of Demand Alarm State

4. PC Link Communication Protocol

4.1 Overview

4.1.1 Configuration of Command

4.1.2 Configuration of Response

4.1.3 Response Error Codes

4.1.4 Specifying Broadcast

4.2 Command and Response