Emerson Bettis XTE3000 User manual

Bettis XTE3000
Modbus RTU Module
Installation, Operation and Maintenance Manual
VCIOM-15081-EN Rev. 7
October 2022

Notes
October 2022
Installation, Operation and Maintenance Manual
VCIOM-15081-EN Rev. 7
Revision Details
Revision Details
Rev. Date Description Prepared Checked Approved
7 October 2022 Update Figure 15

I
Installation, Operation and Maintenance Manual
VCIOM-15081-EN Rev. 7
Table of Contents
October 2022
Table of Contents
Table of Contents
Section 1: Introduction
1.1 References .................................................................................................... 1
1.2 Modbus RTU or ASCII .................................................................................... 1
Section 2: Operation and Storage
Operation and Storage............................................................................................ 2
Section 3: Communication Features
Communication Features........................................................................................ 3
Section 4: Modbus RTU Module
4.1 On Board Indications and Jumpers................................................................. 5
Section 5: Modbus RTU Protocol Description
Modbus RTU Protocol Description........................................................................... 6
Section 6: Modbus Wirings
6.1 RS485 Transmission Mode ............................................................................ 7
Section 7: Modbus I/O List
7.1 Discrete Inputs............................................................................................ 10
7.2 Coils............................................................................................................ 11
7.3 Analog Inputs.............................................................................................. 13
7.4 Holding Registers........................................................................................ 20
Section 8: Modbus Function Description
8.1 Function Code 01 (0x01) Read Coils Status.................................................. 34
8.2 Function Code 16 (0x10) Write Multiple Registers ...................................... 35
8.3 Function Code 03 (0x03) Read Holding Registers ........................................ 36
8.4 Function Code 04 (0x04) Read Input Registers ............................................ 37
8.5 Function Code 05 (0x05) Write Single Coil .................................................. 38
8.6 Function Code 06 (0x06) Write Single Register............................................ 39
8.7 Function Code 08 (0x08) Diagnostic ........................................................... 40
8.7.1 Sub-Function 00 (0x0000) Return Query Data.................................. 40
8.7.2 Sub-Function 11 (0x000B) Return Bus Message Count...................... 40
8.7.3 Sub-Function 12 (0x000C) Return Bus Communication Error Count . 40
8.7.4 Sub-Function 13 (0x000D) Return Bus Exception Error Count ........... 41
8.7.5 Sub-Function 14 (0x000E) Return Slave Message Count ................... 41
8.7.6 Sub-Function 17 (0x0011) Return Slave Busy Count ......................... 41
8.7.7 Sub-Function 18 (0x0012) Return Bus Character Overrun Count ...... 41
8.8 Function Code 15 (0x0F) Write Multiple Coils.............................................. 42
8.9 Function Code 16 (0x10) Write Multiple Registers....................................... 43
8.10 Function Code 17 (0x11) Report Slave ID..................................................... 44
8.11 Exception Codes.......................................................................................... 45

II
Table of Contents
October 2022
Installation, Operation and Maintenance Manual
VCIOM-15081-EN Rev. 7
Table of Contents
Section 9: Conguration via Local Interface of XTE3000
9.1 BUS Control................................................................................................. 46
9.2 Positioner Function ..................................................................................... 48
9.3 Fail Safe Function ........................................................................................ 49
9.4 Viewing Transmission Info........................................................................... 50
9.5 BUS Signal Failure Indication........................................................................ 50
9.6 Actuator Terminal Board ............................................................................. 51
Section 10: Annex A
10.1 Replacement of 494MOD1000 with 494MOD1200 ..................................... 52
Section 11: Annex B
11.1 Multiple Functionality of ESD Command and Status.................................... 54

Installation, Operation and Maintenance Manual
VCIOM-15081-EN Rev. 7 October 2022
Introduction 1
Section 1: Introduction
Section 1: Introduction
The XTE3000 Modbus RTU is an electronic module that allows connecting the Bettis electrical
actuator XTE3000 to a Modbus RTU serial communication line. The module has its microprocessor, it
is controlled by a program stored internally, it works as a pure BUS interface and does not affect the
actuator control integrity. It is installed inside the actuator housing and takes the electrical power
from the actuator power supply module. The RS485 interface is located on the module board.
The data lines are fully isolated from the actuator electronics.
All features described in this document are applicable for software revision 2.01 or subsequently.
XTE3000 Modbus RTU module can be mounted only on base card revision 9.00 or higher.
1.1 References
Modbus over serial line specication and implementation guide V1.02.
Available from www.modbus.org.
Modbus application protocol specication V1.1b3. Available from www.modbus.org.
XTE3000 Installation, Operation and Maintenance Manual, VCIOM-14012-EN.
1.2 Modbus RTU or ASCII
Modbus protocol is currently supported by most Programmable Logic Controllers (PLCs). Modbus is a
very simple Master/Slave serial protocol. It supports both ASCII (rarely used) and Binary (RTU) form of
transmission. In ASCII transmission mode each 8-bit byte in a message is sent as 2 ASCII characters.
In RTU transmission mode each 8-bit byte is sent as 2 four-bit hexadecimal characters. The main
advantage of RTU mode is that it allows greater character density than in ASCII mode at the same
baud rate.
The structure of a Modbus message is shown below.
Address Function Data Checksum

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Installation, Operation and Maintenance Manual
VCIOM-15081-EN Rev. 7
Operation and Storage
2
Section 2: Operation and Storage
Section 2: Operation and Storage
The module is designed to work and to be stored in the same environment of the actuator.

Installation, Operation and Maintenance Manual
VCIOM-15081-EN Rev. 7 October 2022
Communication Features 3
Section 3: Communication Features
Section 3: Communication Features
Communication Protocol: Modbus RTU
Transmission Technology: RS485, half duplex
Network Topology: Line (BUS) structure
Transmission Medium: Twisted, screened copper cable
Data Rate: 600, 1200, 2400, 4800, 9600, 19200, 38400 bit/s
Device Number: Maximum 32 devices per segment. If more than 32 devices are
present on the BUS, repeaters should be used
Slave Address: From 1 to 247 (address 0 reserved for broadcast messages),
congurable via local operator interface of actuator
BUS Access: Polling between masters and slaves
Electrical Power: Actuator powered
BUS Termination: Available on board, congurable via local operator
interface of actuator
Temperature: -40 °C, +85 °C
Fieldbus Redundancy: Available by setting the MODE function (CH1, CH2, AUTO)
Auto Baud Rate: Available by setting “Baud Rate = AUTO”
EMC Protections: EN 50081-2 and EN 50082-2
Baud Rate: Congurable via local operator interface of actuator
Addressing: Congurable via local operator interface of actuator
Coding System: 8 bits binary, hexadecimal 0-9, A-F. Two hexadecimal
characters contained in each 8-bit eld of the message
Bits per byte: 1 start bit
8 data bits, least signicant bit sent rst
1 bit for Even/Odd parity; no bit for no parity; congurable
via local operator interface of actuator
1 stop bit with parity; 2 Stop bits without parity
Error Check Field: Cyclical Redundancy Check (CRC)

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Installation, Operation and Maintenance Manual
VCIOM-15081-EN Rev. 7
Modbus RTU Module
Section 4: Modbus RTU Module
4
Section 4: Modbus RTU Module
The module consists in a single PCB that is installed inside the actuator housing. It is connected to the
XTE3000 base card via strip connector.
The internal wiring connects the RS485 data lines to the actuator terminal board.
Figure 1 Top Side
Figure 2 Bottom Side

Installation, Operation and Maintenance Manual
VCIOM-15081-EN Rev. 7 October 2022
Modbus RTU Module
Section 4: Modbus RTU Module
5
4.1 On Board Indications and Jumpers
Seven LEDs are mounted on the Modbus RTU module to give the following indications for the eld
service. LEDs indicators are active only when jumper JP1 is closed.
DL1 (green) Power Supply: ON: When the Modbus RTU module is correctly
powered from the main power supply
OFF: When the Modbus RTU module is not correctly
powered from the power supply
DL2 (green) CH1 Comm. Status: ON: Data Message received or transmit from
Modbus RTU interface
OFF: Silence between Data Modbus messages
BLINK: Auto Baud Rate Running
DL3 (green) CH2 Comm. Status: ON: Data Message received or transmit from
Modbus RTU interface
OFF: Silence between Data Modbus messages
BLINK: Auto Baud Rate Running
DL4 (green) Termination CH1: ON: Termination Resistance Active on CH1
OFF: Termination Resistance Not Active on CH1
DL5 (green) Termination CH2: ON: Termination Resistance Active on CH2
OFF: Termination Resistance Not Active on CH2
DL6 (red) Base Card Comm. Status: ON: Communication Errors
OFF: Not Communication Errors
DL7 (red) Data Area Empty: ON: When Data Area on interface card is not yet loaded
OFF: When Data Area is completely loaded
BLINK: When Data Area is being read from base card
JP1: LEDs jumper. Short this jumper to power LEDs. (default OFF)
JP2: Program jumper. Used to download new rmware on microcontroller (manufacturer use only)

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Installation, Operation and Maintenance Manual
VCIOM-15081-EN Rev. 7
Modbus RTU Protocol
Section 5: Modbus RTU Protocol
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Section 5: Modbus RTU Protocol Description
Modbus protocol is a messaging structure, used in a wide range of application in process automation
to establish master-slave communication between intelligent devices. Since Modbus is only a
messaging structure, it is independent from the physical layer. It is traditionally implemented using
RS232 or RS422 or RS485. The central controllers (as PLC) communicate via serial connection
with eld devices (as sensors, actuators). The central controller (called master) reads the input
information from the eld devices (called slaves) and writes the output information to the slaves.
The master initiates the transmission which is called “query.” The slave devices answer by sending the
requested data (called “response”) and performing the action requested in the query. The master can
address individual slaves or can send a broadcast message to all slaves.
The gure below shows a query-response cycle.
Figure 3
Address Function Data Checksum
Address Function Data Checksum
response
query
No response from slaves is done in case of broadcast message. Address 0 is used for the
broadcast message.
If a slave receives the request, but detects a communication error (parity, CRC, etc.) no response
is returned.
If a slave receives the request without a communication error, but cannot handle it (for example,
if the request is to read a non-existent output or register), the slave will return an exception response
informing the master of the nature of error.